Determining The Plane of The Kuiper Belt with OSSOS

NASA Astrophysics Data System (ADS)

Van Laerhoven, Christa; Kavelaars, J. J.; Volk, Kathryn; Gladman, Brett; Petit, Jean-Marc

2018-04-01

We present the OSSOS-based measurement of the semi-major axes dependent orientation of the Kuiper Belt plane. A Kuiper Belt object's (KBO's) inclination can be broken down into a forced component and a free component. The inclination and longitude of ascending node of the forced inclination define the 'forced plane,' the plane about which the KBO's inclination will precess. Secular theory predicts that this forced plane should depend on semi-major axis. For example, the nu18 secular resonance should create a significant warp in the forced planet near 40.5 au (Chiang and Choi 2008). Not predicted by secular theory is a warp in the distant Kuiper Belt (semi-major axes greater than 50 au) seen by Volk and Malhotra 2016 using KBOs from the Minor Planet Catalog. We investigate what the inclination distribution is for objects beyond Neptune as a function of semi-major axis using the OSSOS characterized sample. Through use of the OSSOS survey simulator we test various underlying orbital distributions and compare how the survey would have observed those populations to the actual observed sample. In particular, we test various widths for the inclination distribution about various local forcing planes for the kernel, stirred, and hot classical Kuiper Belt. We find that the forced plane in matches well with the expected forced plane from secular theory. Through most of the main Kuiper Belt (between the 3:2 and 2:1 resonances), we can reject both the ecliptic plane and the invariable plane as the true forced plane. Only as the expected secularly forced plane approaches the invariable plane does the invariable plane become non-rejectable. In the outer Kuiper Belt we reject the nominal mean-plane measured by Volk and Malhotra, but smaller warps are still allowed by the data.

THE DENSITY OF MID-SIZED KUIPER BELT OBJECT 2002 UX25 AND THE FORMATION OF THE DWARF PLANETS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, M. E., E-mail: mbrown@caltech.edu

The formation of the largest objects in the Kuiper belt, with measured densities of ∼1.5 g cm{sup –3} and higher, from the coagulation of small bodies, with measured densities below 1 g cm{sup –3}, is difficult to explain without invoking significant porosity in the smallest objects. If such porosity does occur, measured densities should begin to increase at the size at which significant porosity is no longer supported. Among the asteroids, this transition occurs for diameters larger than ∼350 km. In the Kuiper belt, no density measurements have been made between ∼350 km and ∼850 km, the diameter range where porosities might first begin tomore » drop. Objects in this range could provide key tests of the rock fraction of small Kuiper belt objects (KBOs). Here we report the orbital characterization, mass, and density determination of the 2002 UX25 system in the Kuiper belt. For this object, with a diameter of ∼650 km, we find a density of 0.82 ± 0.11 g cm{sup –3}, making it the largest solid known object in the solar system with a measured density below that of pure water ice. We argue that the porosity of this object is unlikely to be above ∼20%, suggesting a low rock fraction. If the currently measured densities of KBOs are a fair representation of the sample as a whole, creating ∼1000 km and larger KBOs with rock mass fractions of 70% and higher from coagulation of small objects with rock fractions as low as those inferred from 2002 UX25 is difficult.« less

The Phase Space Structure Near Neptune Resonances in the Kuiper Belt

NASA Technical Reports Server (NTRS)

Malhotra, Renu

1996-01-01

The Solar system beyond Neptune is believed to house a population of small primordial bodies left over from the planet formation process. The region up to heliocentric distance -50 AU (a.k.a. the Kuiper Belt) may be the source of the observed short-period comets. In this region, the phase space structure near orbital resonances with Neptune is of special interest for the long-term stability of orbits. There is reason to believe that a significant fraction (perhaps most) of the Kuiper Belt objects reside preferentially in these resonance locations. This paper describes the dynamics of small objects near the major orbital resonances with Neptune. Estimates of the widths of stable resonance zones as well as the properties of resonant orbits are obtained from the circular, planar restricted three-body model. Although this model does not contain the full complexity of the long-term orbital dynamics of Kuiper Belt objects subject to the full N-body perturbations of all the planets, it does provide a baseline for the phase space structure and properties of resonant orbits in the trans-Neptunian Solar system.

Cosmic Ray Mantle Visibility on Kuiper Belt Objects

NASA Technical Reports Server (NTRS)

Cooper, John F.; Hill, Matt E.; Richardson, J. D.; Sturner, S. J.

2006-01-01

Optically red objects constitute the dynamically cold, old component of the Classical Kuiper Belt (40 - 47 AU) with heliocentric orbits of low eccentricity and inclination. The red colors likely arise from primordial mixed ices processed by irradiation to meters in surface depth over the past four billion years, since the time of giant planet migration and Kuiper Belt stirring, at relatively moderate dosages of 60 gigarads provided by galactic cosmic ray protons and heavier ions. The red cosmic ray mantle is uniformly visible on the cold classical objects beneath a minimally thin eroded layer of more neutrally colored material arising from cumulative effects of heliospheric particle irradiation. The radiation fluxes are lowest in the middle heliospheric region containing the Classical Kuiper Belt and increase from there both towards and away from the Sun. Despite increasing irradiation at various times of solar system history from increases in solar and interstellar ion fluxes, the red object region has apparently never reached sufficiently high dosage levels to neutralize in color the red mantle material. Erosion processes, including plasma sputtering and micrometeroid impacts, act continuously to reduce thickness of the upper neutral crust and expose the cosmic ray mantle. A deeper layer at tens of meters and more may consist of relatively unprocessed ices that can erupt to the surface by larger impacts or cryovolcanism and account for brighter surfaces of larger objects such as 2003 UB313. Surface colors among the Kuiper Belt and other icy objects of the outer solar system are then a function, assuming uniform primordial composition, of relative thickness for the three layers and of the resurfacing age dependent on the orbital and impact history of each object.

THE CANADA-FRANCE ECLIPTIC PLANE SURVEY-L3 DATA RELEASE: THE ORBITAL STRUCTURE OF THE KUIPER BELT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kavelaars, J. J.; Jones, R. L.; Murray, I.

2009-06-15

We report the orbital distribution of the trans-Neptunian comets discovered during the first discovery year of the Canada-France Ecliptic Plane Survey (CFEPS). CFEPS is a Kuiper Belt object survey based on observations acquired by the Very Wide component of the Canada-France-Hawaii Telescope Legacy Survey (LS-VW). The first year's detections consist of 73 Kuiper Belt objects, 55 of which have now been tracked for three years or more, providing precise orbits. Although this sample size is small compared to the world-wide inventory, because we have an absolutely calibrated and extremely well-characterized survey (with known pointing history) we are able to de-biasmore » our observed population and make unbiased statements about the intrinsic orbital distribution of the Kuiper Belt. By applying the (publically available) CFEPS Survey Simulator to models of the true orbital distribution and comparing the resulting simulated detections to the actual detections made by the survey, we are able to rule out several hypothesized Kuiper Belt object orbit distributions. We find that the main classical belt's so-called 'cold' component is confined in semimajor axis (a) and eccentricity (e) compared to the more extended 'hot' component; the cold component is confined to lower e and does not stretch all the way out to the 2:1 resonance but rather depletes quickly beyond a = 45 AU. For the cold main classical belt population we find a robust population estimate of N(H{sub g} < 10) = 50 {+-} 5 x 10{sup 3} and find that the hot component of the main classical belt represents {approx}60% of the total population. The inner classical belt (sunward of the 3:2 mean-motion resonance) has a population of roughly 2000 trans-Neptunian objects with absolute magnitudes H{sub g} < 10, and may not share the inclination distribution of the main classical belt. We also find that the plutino population lacks a cold low-inclination component, and so, the population is somewhat larger than recent estimates; our analysis shows a plutino population of N(H{sub g} < 10){approx} 25{sup +25} {sub -12} x 10{sup 3}compared to our estimate of the size of main classical Kuiper Belt population of N(H{sub g} < 10) {approx} (126{sup +50} {sub -46}) x 10{sup 3}.« less

The Creation of Haumea's Collisional Family

NASA Astrophysics Data System (ADS)

Schlichting, Hilke E.; Sari, Re'em

2009-08-01

Recently, the first collisional family was discovered in the Kuiper Belt. The parent body of this family, Haumea, is one of the largest objects in the Kuiper Belt and is orbited by two satellites. It has been proposed that the Haumea family was created from dispersed fragments that resulted from a giant impact. This proposed origin of the Haumea family is however in conflict with the observed velocity dispersion between the family members (~ 140 m s-1) which is significantly less than the escape velocity from Haumea's surface (~ 900 m s-1). In this paper we propose a different formation scenario for Haumea's collisional family. In our scenario the family members are ejected while in orbit around Haumea. This scenario, therefore, naturally gives rise to a lower velocity dispersion among the family members than expected from direct ejection from Haumea's surface. In our scenario Haumea's giant impact forms a single moon that tidally evolves outward until it suffers a destructive collision from which the family is created. We show that this formation scenario yields a velocity dispersion of ~ 190 m s-1 among the family members which is in good agreement with the observations. We discuss an alternative scenario that consists of the formation and tidal evolution of several satellites that are ejected by collisions with unbound Kuiper Belt objects. However, the formation of the Haumea family in this latter way is difficult to reconcile with the large abundance of Kuiper Belt binaries. We, therefore, favor forming the family by a destructive collision of a single moon of Haumea. The probability for Haumea's initial giant impact in today's Kuiper Belt is less than 10-3. In our scenario, however, Haumea's giant impact can occur before the excitation of the Kuiper Belt and the ejection of the family members afterward. This has the advantage that one can preserve the dynamical coherence of the family and explain Haumea's original giant impact, which is several orders of magnitude more likely to have occurred in the primordial dynamically cold Kuiper Belt compared to the dynamically excited Kuiper Belt today.

Size and Albedo of Kuiper Belt Object 55636 from a Stellar Occultation

DTIC Science & Technology

2010-06-01

Santa Barbara, California 93117, USA. 10University of Hawai’i, Hilo , Hawai’i 96720-4091, USA. 11Department of Terrestrial Magnetism, Carnegie Institution...Jewitt, D. Hawaii Kuiper belt variability project: an update. Earth Moon Planets 92, 207–219 (2003). 11. Grundy, W., Noll, K. & Stephens, D

From Kuiper Belt to Comet: The Shapes of the Nuclei

NASA Astrophysics Data System (ADS)

Jewitt, D.; Sheppard, S.; Fernandez, Y.

2003-05-01

It is widely believed that escaped objects from the Kuiper Belt are the source of both the Centaurs and the nuclei of the Jupiter Family Comets (JFCs). If the JFC nuclei are produced by collisional breakup of parent objects in the Kuiper Belt, then it is reasonable to expect that their shape distribution should be consistent with those of fragments produced in disintegrative laboratory experiments, or with the small main-belt asteroids (which are produced collisionally). We test this idea using a sample of eleven well-observed cometary nuclei. Our main result is that the nuclei are, on average, much more elongated than either the collisionally produced small main-belt asteroids or the fragments created in laboratory impact experiments. Several interpretations of this systematic shape difference are possible (including the obvious one that the JFC nuclei are not, after all, produced collisionally in the Kuiper Belt). Our preferred explanation, however, is that the asphericities of the nuclei have been modified by one or more processes of mass loss. An implication of this interpretation is that the JFC nuclei in our sample are highly evolved, having lost a major part of their original mass. In turn, this implies that the angular momenta of the nuclei are also non-primordial: the JFC nuclei are highly physically evolved objects. We will discuss the evidence supporting these conclusions. This work has been recently published in Astronomical Journal, 125, 3366-3377 (2003).

2004 EW95: A Phyllosilicate-bearing Carbonaceous Asteroid in the Kuiper Belt

NASA Astrophysics Data System (ADS)

Seccull, Tom; Fraser, Wesley C.; Puzia, Thomas H.; Brown, Michael E.; Schönebeck, Frederik

2018-03-01

Models of the Solar System’s dynamical evolution predict the dispersal of primitive planetesimals from their formative regions among the gas-giant planets due to the early phases of planetary migration. Consequently, carbonaceous objects were scattered both into the outer asteroid belt and out to the Kuiper Belt. These models predict that the Kuiper Belt should contain a small fraction of objects with carbonaceous surfaces, though to date, all reported visible reflectance spectra of small Kuiper Belt Objects (KBOs) are linear and featureless. We report the unusual reflectance spectrum of a small KBO, (120216) 2004 EW95, exhibiting a large drop in its near-UV reflectance and a broad shallow optical absorption feature centered at ∼700 nm, which is detected at greater than 4σ significance. These features, confirmed through multiple epochs of spectral photometry and spectroscopy, have respectively been associated with ferric oxides and phyllosilicates. The spectrum bears striking resemblance to those of some C-type asteroids, suggesting that 2004 EW95 may share a common origin with those objects. 2004 EW95 orbits the Sun in a stable mean motion resonance with Neptune, at relatively high eccentricity and inclination, suggesting it may have been emplaced there by some past dynamical instability. These results appear consistent with the aforementioned model predictions and are the first to show a reliably confirmed detection of silicate material on a small KBO.

Kuiper Belt Dust Grains as a Source of Interplanetary Dust Particles

NASA Technical Reports Server (NTRS)

Liou, Jer-Chyi; Zook, Herbert A.; Dermott, Stanley F.

1996-01-01

The recent discovery of the so-called Kuiper belt objects has prompted the idea that these objects produce dust grains that may contribute significantly to the interplanetary dust population. In this paper, the orbital evolution of dust grains, of diameters 1 to 9 microns, that originate in the region of the Kuiper belt is studied by means of direct numerical integration. Gravitational forces of the Sun and planets, solar radiation pressure, as well as Poynting-Robertson drag and solar wind drag are included. The interactions between charged dust grains and solar magnetic field are not considered in the model. Because of the effects of drag forces, small dust grains will spiral toward the Sun once they are released from their large parent bodies. This motion leads dust grains to pass by planets as well as encounter numerous mean motion resonances associated with planets. Our results show that about 80% of the Kuiper belt grains are ejected from the Solar System by the giant planets, while the remaining 20% of the grains evolve all the way to the Sun. Surprisingly, the latter dust grains have small orbital eccentricities and inclinations when they cross the orbit of the Earth. This makes them behave more like asteroidal than cometary-type dust particles. This also enhances their chances of being captured by the Earth and makes them a possible source of the collected interplanetary dust particles; in particular, they represent a possible source that brings primitive/organic materials from the outer Solar System to the Earth. When collisions with interstellar dust grains are considered, however, Kuiper belt dust grains around 9 microns appear likely to be collisionally shattered before they can evolve toward the inner part of the Solar System. The collision destruction can be applied to Kuiper belt grains up to about 50 microns. Therefore, Kuiper belt dust grains within this range may not be a significant part of the interplanetary dust complex in the inner Solar System.

Assessing Backwards Integration as a Method of KBO Family Finding

NASA Astrophysics Data System (ADS)

Benfell, Nathan; Ragozzine, Darin

2018-04-01

The age of young asteroid collisional families can sometimes be determined by using backwards n-body integrations of the solar system. This method is not used for discovering young asteroid families and is limited by the unpredictable influence of the Yarkovsky effect on individual specific asteroids over time. Since these limitations are not as important for objects in the Kuiper belt, Marcus et al. 2011 suggested that backwards integration could be used to discover and characterize collisional families in the outer solar system. But various challenges present themselves when running precise and accurate 4+ Gyr integrations of Kuiper Belt objects. We have created simulated families of Kuiper Belt Objects with identical starting locations and velocity distributions, based on the Haumea Family. We then ran several long-term test integrations to observe the effect of various simulation parameters on integration results. These integrations were then used to investigate which parameters are of enough significance to require inclusion in the integration. Thereby we determined how to construct long-term integrations that both yield significant results and require manageable processing power. Additionally, we have tested the use of backwards integration as a method of discovery of potential young families in the Kuiper Belt.

A POSSIBLE DIVOT IN THE SIZE DISTRIBUTION OF THE KUIPER BELT'S SCATTERING OBJECTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shankman, C.; Gladman, B. J.; Kaib, N.

Via joint analysis of a calibrated telescopic survey, which found scattering Kuiper Belt objects, and models of their expected orbital distribution, we explore the scattering-object (SO) size distribution. Although for D > 100 km the number of objects quickly rise as diameters decrease, we find a relative lack of smaller objects, ruling out a single power law at greater than 99% confidence. After studying traditional ''knees'' in the size distribution, we explore other formulations and find that, surprisingly, our analysis is consistent with a very sudden decrease (a divot) in the number distribution as diameters decrease below 100 km, whichmore » then rises again as a power law. Motivated by other dynamically hot populations and the Centaurs, we argue for a divot size distribution where the number of smaller objects rises again as expected via collisional equilibrium. Extrapolation yields enough kilometer-scale SOs to supply the nearby Jupiter-family comets. Our interpretation is that this divot feature is a preserved relic of the size distribution made by planetesimal formation, now ''frozen in'' to portions of the Kuiper Belt sharing a ''hot'' orbital inclination distribution, explaining several puzzles in Kuiper Belt science. Additionally, we show that to match today's SO inclination distribution, the supply source that was scattered outward must have already been vertically heated to the of order 10 Degree-Sign .« less

Colours of the Outer Solar System Origins Survey (Col-OSSOS): New Insights into Kuiper belt Surfaces

NASA Astrophysics Data System (ADS)

Schwamb, M. E.; Fraser, W. C.; Bannister, M. T.; Pike, R. E.; Marsset, M.; Kavelaars, J. J.; Benecchi, S.; Delsanti, A.; Lehner, M. J.; Thirouin, A.; Guilbert-Lepoutre, A.; Peixinho, N.; Vernazza, P.

2016-12-01

The icy planetesimals of the Kuiper belt inform our knowledge about the growth of planetary embryos and our Solar System's dynamical history. The majority of the known Pluto-sized Kuiper belt objects (KBOs) are bright enough for their surfaces to be studied through optical and infrared spectroscopy. But for the typical smaller r mag > 22 mag KBOs, we must rely on what colors reveal by proxy, and this picture of Kuiper belt surfaces remains incomplete. Previous studies in this size range examined the hodgepodge set of KBOs discovered by surveys with varying and sometimes unknown detection biases that make it challenging to explore the true frequency of surface colors within the Kuiper belt. The Colours of the Outer Solar System Origins Survey (Col-OSSOS) aims to explore and explain the compositional variety within the Kuiper belt through near simultaneous u, g,r and J colors with the Gemini North Telescope and the Canada-France-Hawaii Telescope. The survey targets KBOs brighter than 23.6 r' mag ( 50-300 km) found by the Outer Solar System Origins Survey (OSSOS). With Col-OSSOS, we have a set of colors measured for a KBO sample discovered in a brightness limited survey, with a well-measured detection efficiency. Col-OSSOS will provide a compositional-dynamical map of the Kuiper belt in which to study the end of stages of Neptune migration and the conditions of the early planetesimal disk where these small icy bodies formed. We will give an overview of Col-OSSOS and an update on the program's current status. We will present the photometry from the first 30 KBOs studied from the first complete OSSOS block and examine the implications for Kuiper belt surfaces. We derive the observed and debiased ratio of neutral to red KBOs, measure the masses of the three color populations within the Kuiper belt (the red and neutral dynamically excited population and the red cold classical belt), and explore the radial color distribution in the primordial planetesimal disk before Neptune migration.

Planetary Migration and Kuiper Belt Dynamics

NASA Astrophysics Data System (ADS)

Malhotra, Renu

The Kuiper belt holds memory of the dynamical processes that shaped the architecture of the solar system, including the orbital migration history of the giant planets. We propose studies of the orbital dynamics of the Kuiper Belt in order to understand the origin of its complex dynamical structure and its link to the orbital migration history of the giant planets. By means of numerical simulations, statistical tests, as well as analytical calculations we will (1) investigate the origin of resonant Kuiper belt objects to test alternative scenarios of Neptune's migration history, (2) investigate the long term dynamical evolution of the Haumea family of Kuiper Belt objects in order to improve the age estimate of this family, and (3) investigate resonance-sticking behavior and the Kozai-Lidov mechanism and its role in the origin of the extended scattered disk. These studies directly support the goals of the NASA-OSS program by improving our understanding of the origin of the solar system's architecture. Our results will provide constraints on the nature and timing of the dynamical excitation event that is thought to have occurred in early solar system history and to have determined the architecture of the present-day solar system; our results will also provide deeper theoretical understanding of sticky mean motion resonances which contribute greatly to the longevity of many small bodies, improve our understanding of dynamical transport of planetesimals in planetary systems, and help interpret observations of other planetary systems.

A collisional family of icy objects in the Kuiper belt.

PubMed

Brown, Michael E; Barkume, Kristina M; Ragozzine, Darin; Schaller, Emily L

2007-03-15

The small bodies in the Solar System are thought to have been highly affected by collisions and erosion. In the asteroid belt, direct evidence of the effects of large collisions can be seen in the existence of separate families of asteroids--a family consists of many asteroids with similar orbits and, frequently, similar surface properties, with each family being the remnant of a single catastrophic impact. In the region beyond Neptune, in contrast, no collisionally created families have hitherto been found. The third largest known Kuiper belt object, 2003 EL61, however, is thought to have experienced a giant impact that created its multiple satellite system, stripped away much of an overlying ice mantle, and left it with a rapid rotation. Here we report the discovery of a family of Kuiper belt objects with surface properties and orbits that are nearly identical to those of 2003 EL61. This family appears to be fragments of the ejected ice mantle of 2003 EL61.

Kuiper Belt Object Orbiter Using Advanced Radioisotope Power Sources and Electric Propulsion

NASA Technical Reports Server (NTRS)

Oleson, Steven R.; McGuire, Melissa L.; Dankanich, John; Colozza, Anthony; Schmitz, Paul; Khan, Omair; Drexler, Jon; Fittje, James

2011-01-01

A joint NASA GRC/JPL design study was performed for the NASA Radioisotope Power Systems Office to explore the use of radioisotope electric propulsion for flagship class missions. The Kuiper Belt Object Orbiter is a flagship class mission concept projected for launch in the 2030 timeframe. Due to the large size of a flagship class science mission larger radioisotope power system building blocks were conceptualized to provide the roughly 4 kW of power needed by the NEXT ion propulsion system and the spacecraft. Using REP the spacecraft is able to rendezvous with and orbit a Kuiper Belt object in 16 years using either eleven (no spare) 420 W advanced RTGs or nine (with a spare) 550 W advanced Stirling Radioisotope systems. The design study evaluated integrating either system and estimated impacts on cost as well as required General Purpose Heat Source requirements.

Serendipitous occultations by kilometer size Kuiper Belt with MIOSOTYS

NASA Astrophysics Data System (ADS)

Doressoundiram, A.; Liu, C.-Y.; Maquet, L.; Roques, F.

2017-09-01

MIOSOTYS (Multi-object Instrument for Occultations in the SOlar system and TransitorY Systems) is a multi-fiber positioner coupled with a fast photometry camera. This is a visitor instrument mounted on the 193 cm telescope at the Observatoire de Haute-Provence, France and on the 123 cm telescope at the Calar Alto Observatory, Spain. Our immediate goal is to characterize the spatial distribution and extension of the Kuiper Belt, and the physical size distribution of TNOs. We present the observation campaigns during 2010-2013, objectives and observing strategy. We report the detection of potential candidates for occultation events of TNOs. We will discuss more specifically the method used to process the data and the modelling of diffraction patterns. We, finally present the results obtained concerning the distribution of sub-kilometer TNOs in the Kuiper Belt.

A population of comets in the main asteroid belt.

PubMed

Hsieh, Henry H; Jewitt, David

2006-04-28

Comets are icy bodies that sublimate and become active when close to the Sun. They are believed to originate in two cold reservoirs beyond the orbit of Neptune: the Kuiper Belt (equilibrium temperatures of approximately 40 kelvin) and the Oort Cloud (approximately 10 kelvin). We present optical data showing the existence of a population of comets originating in a third reservoir: the main asteroid belt. The main-belt comets are unlike the Kuiper Belt and Oort Cloud comets in that they likely formed where they currently reside and may be collisionally activated. The existence of the main-belt comets lends new support to the idea that main-belt objects could be a major source of terrestrial water.

HUBBLE DETECTION OF COMET NUCLEUS AT FRINGE OF SOLAR SYSTEM

NASA Technical Reports Server (NTRS)

2002-01-01

This is sample data from NASA's Hubble Space Telescope that illustrates the detection of comets in the Kuiper Belt, a region of space beyond the orbit of the planet Neptune. This pair of images, taken with the Wide Field Planetary Camera 2 (WFPC2), shows one of the candidate Kuiper Belt objects found with Hubble. Believed to be an icy comet nucleus several miles across, the object is so distant and faint that Hubble's search is the equivalent of finding the proverbial needle-in-haystack. Each photo is a 5-hour exposure of a piece of sky carefully selected such that it is nearly devoid of background stars and galaxies that could mask the elusive comet. The left image, taken on August 22, 1994, shows the candidate comet object (inside circle) embedded in the background. The right picture, take of the same region one hour forty-five minutes later shows the object has apparently moved in the predicted direction and rate of motion for a kuiper belt member. The dotted line on the images is a possible orbit that this Kuiper belt comet is following. A star (lower right corner) and a galaxy (upper right corner) provide a static background reference. In addition, other objects in the picture have not moved during this time, indicating they are outside our solar system. Through this search technique astronomers have identified 29 candidate comet nuclei belonging to an estimated population of 200 million particles orbiting the edge of our solar system. The Kupier Belt was theorized 40 years ago, and its larger members detected several years ago. However, Hubble has found the underlying population of normal comet-sized bodies. Credit: A. Cochran (University of Texas) and NASA

New Horizons High-Phase Observations of Distant Kuiper Belt Objects

NASA Astrophysics Data System (ADS)

Verbiscer, A.; Porter, S.; Spencer, J. R.; Buie, M. W.; Benecchi, S.; Weaver, H. A., Jr.; Buratti, B. J.; Ennico Smith, K.; Olkin, C.; Stern, S. A.; Young, L. A.; Cheng, A. F.

2017-12-01

From its unique vantage point far from the Sun, NASA's New Horizons spacecraft has observed Kuiper Belt Objects at separations ranging from 0.1 to 70 AU, and at solar phase angles far larger than those attainable from Earth. We have constructed the first KBO solar phase curves with substantial phase angle coverage for targets including Haumea, Makemake, Quaoar, Arawn (Porter et al. 2016, Astrophys. J. Lett. 828, L15), and 2002 MS4. We compare the phase functions of these KBOs with those of objects in the Pluto system and other Solar System bodies such as comets, asteroids, and icy satellites. For KBOs with known geometric albedos, these measurements enable calculation of the phase integral, an important photometric property that characterizes the energy balance on a distant KBO surface. During its approach to 2014 MU69, and following its close encounter on 1 January 2019, New Horizons will continue to exploit its capabilities as NASA's only observatory within the Kuiper Belt itself.

Collisional Processing of Olivine and Pyroxene in Cometary Dust

NASA Technical Reports Server (NTRS)

Lederer, S. M.; Cintala, M. J.; Olney, R. D.; Keller, L. P.; Nakamura-Messenger, K.; Zolensky, M.

2008-01-01

According to the nebular theory of solar-system formation, collisions between bodies occurred frequently early in the solar system s history and continue at a lower rate even today. Collisions have reworked the surface compositions and structures of cometary nuclei, though to an unknown degree. The majority of the collisional history of a typical Jupiter-family comet takes place while it resides in the Kuiper Belt. Impacts occur on the surfaces of small bodies over a large range of velocities by impactors of all sizes, but typical encounter speeds within the Kuiper Belt are 1.5 to 2.0 km/s[1]. Durda and Stern suggest that the interiors of most cometary nuclei with diameters <5 km have been heavily damaged by collisions [2]. They estimate that over a period of 3.5 Gy, a nucleus with a diameter of 2 km and an orbit between 35-45 AU will experience 90-300 collisions with objects greater than 8 m in diameter. In this same time interval, collisions between a typical Trans-Neptunian Object (TNO) 200 km in diameter and objects with d > 8 m would rework up to one-third of that TNO s surface. In fact, it has been proposed that most short-period comets from the Kuiper Belt (90%) are collisional fragments from larger TNOs - not primordial objects themselves [3] - and that most short-period comets from the Kuiper Belt will be collisionally processed both on their surfaces as well as in their interiors.

The Generation of the Distant Kuiper Belt by Planet Nine from an Initially Broad Perihelion Distribution

NASA Astrophysics Data System (ADS)

Khain, Tali; Batygin, Konstantin; Brown, Michael E.

2018-04-01

The observation that the orbits of long-period Kuiper Belt objects are anomalously clustered in physical space has recently prompted the Planet Nine hypothesis - the proposed existence of a distant and eccentric planetary member of our Solar System. Within the framework of this model, a Neptune-like perturber sculpts the orbital distribution of distant Kuiper Belt objects through a complex interplay of resonant and secular effects, such that the surviving orbits get organized into apsidally aligned and anti-aligned configurations with respect to Planet Nine's orbit. We present results on the role of Kuiper Belt initial conditions on the evolution of the outer Solar System using numerical simulations. Intriguingly, we find that the final perihelion distance distribution depends strongly on the primordial state of the system, and demonstrate that a bimodal structure corresponding to the existence of both aligned and anti-aligned clusters is only reproduced if the initial perihelion distribution is assumed to extend well beyond 36 AU. The bimodality in the final perihelion distance distribution is due to the permanently stable objects, with the lower perihelion peak corresponding to the anti-aligned orbits and the higher perihelion peak corresponding to the aligned orbits. We identify the mechanisms that enable the persistent stability of these objects and locate the regions of phase space in which they reside. The obtained results contextualize the Planet Nine hypothesis within the broader narrative of solar system formation, and offer further insight into the observational search for Planet Nine.

Water Ice in 2060 Chiron and Its Implications for Centaurs and Kuiper Belt Objects.

PubMed

Luu; Jewitt; Trujillo

2000-03-10

We report the detection of water ice in the Centaur 2060 Chiron, based on near-infrared spectra (1.0-2.5 µm) taken with the 3.8 m United Kingdom Infrared Telescope and the 10 m Keck Telescope. The appearance of this ice is correlated with the recent decline in Chiron's cometary activity: the decrease in the coma cross section allows previously hidden solid-state surface features to be seen. We predict that water ice is ubiquitous among Centaurs and Kuiper Belt objects, but its surface coverage varies from object to object and thus determines its detectability and the occurrence of cometary activity.

A Kuiper Belt Pair? Artist's Concept of 2014 MU69 as a Binary Object

NASA Image and Video Library

2017-08-03

This is one artist's concept of Kuiper Belt object 2014 MU69, the next flyby target for NASA's New Horizons mission. This binary concept is based on telescope observations made at Patagonia, Argentina, on July 17, 2017, when MU69 passed in front of a star. New Horizons scientists theorize that it could be a single body with a large chunk taken out of it, or two bodies that are close together or even touching. https://photojournal.jpl.nasa.gov/catalog/PIA21867

A celestial gamma-ray foreground due to the albedo of small solar system bodies and a remote probe of the interstellar cosmic ray spectrum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moskalenko, Igor V.; Porter, Troy A.; Digel, Seth W.

2007-12-17

We calculate the {gamma}-ray albedo flux from cosmic-ray (CR) interactions with the solid rock and ice in Main Belt asteroids and Kuiper Belt objects (KBOs) using the Moon as a template. We show that the {gamma}-ray albedo for the Main Belt and Kuiper Belt strongly depends on the small-body mass spectrum of each system and may be detectable by the forthcoming Gamma Ray Large Area Space Telescope (GLAST). The orbits of the Main Belt asteroids and KBOs are distributed near the ecliptic, which passes through the Galactic center and high Galactic latitudes. If detected, the {gamma}-ray emission by the Mainmore » Belt and Kuiper Belt has to be taken into account when analyzing weak {gamma}-ray sources close to the ecliptic, especially near the Galactic center and for signals at high Galactic latitudes, such as the extragalactic {gamma}-ray emission. Additionally, it can be used to probe the spectrum of CR nuclei at close-to-interstellar conditions, and the mass spectrum of small bodies in the Main Belt and Kuiper Belt. The asteroid albedo spectrum also exhibits a 511 keV line due to secondary positrons annihilating in the rock. This may be an important and previously unrecognized celestial foreground for the INTErnational Gamma-Ray Astrophysics Laboratory (INTEGRAL) observations of the Galactic 511 keV line emission including the direction of the Galactic center.« less

Colours of the Outer Solar System Origins Survey: An Update

NASA Astrophysics Data System (ADS)

Schwamb, Megan E.; Fraser, Wesley C.; Pike, Rosemary E.; Bannister, Michele T.; Marsset, Michaël; Kavelaars, J. J.; Benecchi, Susan; Delsanti, Audrey C.; Lehner, Matthew J.; Wang, Shiang-Yu; Thirouin, Audrey; Nesvorný, David

2018-01-01

The vast majority of the known dwarf-planet sized bodies are bright enough to be studied through optical and infrared spectroscopy. As a result, we have an understanding of the surface properties for the largest Kuiper belt objects (KBOs) which retain their primordial inventory of volatile ices. For the typically smaller > 22 mag KBO, we must rely instead on what colors reveal by proxy; yet this picture remains incomplete. Most KBO physical property studies examine the hodgepodge set of objects discovered by various surveys with different and varying detection biases that make it difficult if not impossible to reliably estimate the sizes of the different surface color groupings (compositional classes) residing in the modern-day Kuiper belt.The Colours of the Outer Solar System Origins Survey (Col-OSSOS) probes the surface properties within the Kuiper belt primarily through near simultaneous g,r and J colors with the Gemini North Telescope and u-band with Canada-France-Hawaii Telescope. The project aims to target ~100 KBOs brighter than 23.6 r‧ mag found by the Outer Solar System Origins Survey (OSSOS), a survey with a well-measured detection efficiency. Thus, Col-OSSOS provides the first brightness-complete, compositional-dynamical map of the Outer Solar System, probing in a new light the radial color distribution in the primordial planetesimal disk from which KBOs originated. We will provide an update on the current status of the program highlighting results from the first two years of the survey; including size estimates of the two color KBO subgroups (the red and neutral surfaces) within the dynamically excited Kuiper belt and implications for the early planetesimal disk composition based on neutral-colored binaries found in the cold classical Kuiper belt.

Missions to the Outer Solar System and Beyond - Concept Study for a Kuiper Belt Sample-Return

NASA Astrophysics Data System (ADS)

Ganapathy, Rohan M.

The exploration of Kuiper belt objects (KBOs) might deliver crucial data for answering questions about the evolution of the solar system and the origin of life. Whereas the current New Horizons mission performs a flyby at KBOs, an in-depth exploration of the Kuiper belt requires an orbiter, lander or even a sample return. In this paper, we present a range of potential mission architectures for a Kuiper belt sample return mission. We use the Systems Modeling Language (SysML) for the necessary modeling and the systems engineering tool MagicDraw. A process similar to the NASA Rapid Mission Architecture approach was used. We start with a rationale a KBO sample return, dene science objectives, high-level requirements and select a strawman payload. From a key trade-matrix, mission architecture options are generated. Finally, necessary technologies and prerequisites for the mission are identied. We conclude that one of the dwarf planets Pluto, Haumea, Orcus or Quaoar and their moons should be considered as a target for the mission. The samples should be collected from the dwarf planet of choice or from its moon(s), which omits the rather high velocity requirements for a landing and departure from the dwarf planet itself. Attractive mission architectures include radioisotopic electric propulsion-based missions, missions with a combination of a solar electric propulsion stage and radioisotopic electric propulsion, or missions using nuclear electric propulsion.

The extreme Kuiper Belt binary 2001 QW322.

PubMed

Petit, J-M; Kavelaars, J J; Gladman, B J; Margot, J L; Nicholson, P D; Jones, R L; Parker, J Wm; Ashby, M L N; Bagatin, A Campo; Benavidez, P; Coffey, J; Rousselot, P; Mousis, O; Taylor, P A

2008-10-17

The study of binary Kuiper Belt objects helps to probe the dynamic conditions present during planet formation in the solar system. We report on the mutual-orbit determination of 2001 QW322, a Kuiper Belt binary with a very large separation whose properties challenge binary-formation and -evolution theories. Six years of tracking indicate that the binary's mutual-orbit period is approximately 25 to 30 years, that the orbit pole is retrograde and inclined 50 degrees to 62 degrees from the ecliptic plane, and, most surprisingly, that the mutual orbital eccentricity is <0.4. The semimajor axis of 105,000 to 135,000 kilometers is 10 times that of other near-equal-mass binaries. Because this weakly bound binary is prone to orbital disruption by interlopers, its lifetime in its present state is probably less than 1 billion years.

DIRECT IMAGING AND SPECTROSCOPY OF A YOUNG EXTRASOLAR KUIPER BELT IN THE NEAREST OB ASSOCIATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Currie, Thayne; Lisse, Carey M.; Kuchner, Marc

2015-07-01

We describe the discovery of a bright, young Kuiper belt–like debris disk around HD 115600, a ∼1.4–1.5 M{sub ⊙}, ∼15 Myr old member of the Sco–Cen OB Association. Our H-band coronagraphy/integral field spectroscopy from the Gemini Planet Imager shows the ring has a (luminosity-scaled) semimajor axis of (∼22 AU) ∼ 48 AU, similar to the current Kuiper belt. The disk appears to have neutral-scattering dust, is eccentric (e ∼ 0.1–0.2), and could be sculpted by analogs to the outer solar system planets. Spectroscopy of the disk ansae reveal a slightly blue to gray disk color, consistent with major Kuiper beltmore » chemical constituents, where water ice is a very plausible dominant constituent. Besides being the first object discovered with the next generation of extreme adaptive optics systems (i.e., SCExAO, GPI, SPHERE), HD 115600's debris ring and planetary system provide a key reference point for the early evolution of the solar system, the structure, and composition of the Kuiper belt and the interaction between debris disks and planets.« less

The Whipple Mission: Exploring the Kuiper Belt and the Oort Cloud

NASA Astrophysics Data System (ADS)

Holman, Matthew J.; Alcock, Charles; Kenter, Almus T.; Kraft, Ralph P.; Nulsen, Paul; Payne, Matthew John; Vrtilek, Jan M.; Murray, Stephen S.; Murray-Clay, Ruth; Schlichting, Hilke; Brown, Michael E.; Livingston, John H.; Trangsrud, Amy R.; Werner, Michael W.

2015-01-01

Whipple will characterize the small body populations of the Kuiper Belt and the Oort Cloud with a blind occultation survey, detecting objects when they briefly (~1 second) interrupt the light from background stars, allowing the detection of much more distant and/or smaller objects than can be seen in reflected sunlight. Whipple will reach much deeper into the unexplored frontier of the outer solar system than any other mission, current or proposed. Whipple will look back to the dawn of the solar system by discovering its most remote bodies where primordial processes left their imprint.Specifically, Whipple will monitor large numbers of stars at high cadences (~12,000 stars at 20 Hz to examine Kuiper Belt events; as many as ~36,000 stars at 5 Hz to explore deep into the Oort Cloud, where events are less frequent). Analysis of the detected events will allow us to determine the size spectrum of bodies in the Kuiper Belt with radii as small as ~1 km. This will allow the testing of models of the growth and later collisional erosion of planetesimals in the earlysolar system. Whipple will explore the Oort Cloud, detecting objects as far out as ~10,000 AU. This will be the first direct exploration of the Oort Cloud since the original hypothesis of 1950.Whipple is a Discovery class mission that will be proposed to NASA in response to the upcoming Announcement of Opportunity. The mission is being developed jointly by the Smithsonian Astrophysical Observatory, Jet Propulsion Laboratory, and Ball Aerospace & Technologies, with telescope optics from L-3 Integrated Optical Systems.

The Whipple Mission: Exploring the Kuiper Belt and the Oort Cloud

NASA Astrophysics Data System (ADS)

Alcock, Charles; Brown, Michael; Gauron, Tom; Heneghan, Cate; Holman, Matthew; Kenter, Almus; Kraft, Ralph; Livingston, John; Murray, Stephen; Murray-Clay, Ruth; Nulsen, Paul; Payne, Matthew; Schlichting, Hilke; Trangsrud, Amy; Vrtilek, Jan; Werner, Michael

2014-11-01

Whipple will characterize the small body populations of the Kuiper Belt and the Oort Cloud with a blind occultation survey, detecting objects when they briefly 1 second) interrupt the light from background stars, allowing the detection of much more distant and/or smaller objects than can be seen in reflected sunlight. Whipple will reach much deeper into the unexplored frontier of the outer solar system than any other mission, current or proposed. Whipple will look back to the dawn of the solar system by discovering its most remote bodies where primordial processes left their imprint.Specifically, Whipple will monitor large numbers of stars at high cadences 12,000 stars at 20 Hz to examine Kuiper Belt events; as many as ~36,000 stars at 5 Hz to explore deep into the Oort Cloud, where events are less frequent). Analysis of the detected events will allow us to determine the size spectrum of bodies in the Kuiper Belt with radii as small as ~1 km. This will allow the testing of models of the growth and later collisional erosion of planetesimals in the early solar system. Whipple will explore the Oort Cloud, detecting objects as far out as ~10,000 AU. This will be the first direct exploration of the Oort Cloud since the original hypothesis of 1950.Whipple is a Discovery class mission that will be proposed to NASA in response to the 2014 Announcement of Opportunity. The mission is being developed jointly by the Smithsonian Astrophysical Observatory, Jet Propulsion Laboratories, and Ball Aerospace & Technologies, with telescope optics from L-3 Integrated Optical Systems.

The Whipple Mission: Exploring the Kuiper Belt and the Oort Cloud

NASA Astrophysics Data System (ADS)

Alcock, C.; Brown, M. E.; Gauron, T.; Heneghan, C.; Holman, M. J.; Kenter, A.; Kraft, R.; Lee, R.; Livingston, J.; Mcguire, J.; Murray, S. S.; Murray-Clay, R.; Nulsen, P.; Payne, M. J.; Schlichting, H.; Trangsrud, A.; Vrtilek, J.; Werner, M.

2014-12-01

Whipple will characterize the small body populations of the Kuiper Belt and the Oort Cloud with a blind occultation survey, detecting objects when they briefly (~1 second) interrupt the light from background stars, allowing the detection of much more distant and/or smaller objects than can be seen in reflected sunlight. Whipple will reach much deeper into the unexplored frontier of the outer solar system than any other mission, current or proposed. Whipple will look back to the dawn of the solar system by discovering its most remote bodies where primordial processes left their imprint. Specifically, Whipple will monitor large numbers of stars at high cadences (~12,000 stars at 20 Hz to examine Kuiper Belt events; as many as ~36,000 stars at 5 Hz to explore deep into the Oort Cloud, where events are less frequent). Analysis of the detected events will allow us to determine the size spectrum of bodies in the Kuiper Belt with radii as small as ~1 km. This will allow the testing of models of the growth and later collisional erosion of planetesimals in the early solar system. Whipple will explore the Oort Cloud, detecting objects as far out as ~10,000 AU. This will be the first direct exploration of the Oort Cloud since the original hypothesis of 1950. Whipple is a Discovery class mission that will be proposed to NASA in response to the 2014 Announcement of Opportunity. The mission is being developed jointly by the Smithsonian Astrophysical Observatory, Jet Propulsion Laboratories, and Ball Aerospace & Technologies, with telescope optics from L-3 Integrated Optical Systems.

Neptune's Eccentricity and the Nature of the Kuiper Belt

NASA Technical Reports Server (NTRS)

Ward, William R.; Hahn, Joseph M.

1998-01-01

The small eccentricity of Neptune may be a direct consequence of apsidal wave interaction with the trans-Neptune population of debris called the Kuiper belt. The Kuiper belt is subject to resonant perturbations from Neptune, so that the transport of angular momentum by density waves can result in orbital evolution of Neptune as well as changes in the structure of the Kuiper belt. In particular, for a belt eroded out to the vicinity of Neptune's 2:1 resonance at about 48 astronomical units, Neptune's eccentricity can damp to its current value over the age of the solar system if the belt contains slightly more than an earth mass of material out to about 75 astronomical units.

The color-magnitude distribution of small Kuiper Belt objects

NASA Astrophysics Data System (ADS)

Wong, Ian; Brown, Michael E.

2015-11-01

Occupying a vast region beyond the ice giants is an extensive swarm of minor bodies known as the Kuiper Belt. Enigmatic in their formation, composition, and evolution, these Kuiper Belt objects (KBOs) lie at the intersection of many of the most important topics in planetary science. Improved instruments and large-scale surveys have revealed a complex dynamical picture of the Kuiper Belt. Meanwhile, photometric studies have indicated that small KBOs display a wide range of colors, which may reflect a chemically diverse initial accretion environment and provide important clues to constraining the surface compositions of these objects. Notably, some recent work has shown evidence for bimodality in the colors of non-cold classical KBOs, which would have major implications for the formation and subsequent evolution of the entire KBO population. However, these previous color measurements are few and mostly come from targeted observations of known objects. As a consequence, the effect of observational biases cannot be readily removed, preventing one from obtaining an accurate picture of the true color distribution of the KBOs as a whole.We carried out a survey of KBOs using the Hyper Suprime-Cam instrument on the 8.2-meter Subaru telescope. Our observing fields targeted regions away from the ecliptic plane so as to avoid contamination from cold classical KBOs. Each field was imaged in both the g’ and i’ filters, which allowed us to calculate the g’-i’ color of each detected object. We detected more than 500 KBOs over two nights of observation, with absolute magnitudes from H=6 to H=11. Our survey increases the number of KBOs fainter than H=8 with known colors by more than an order of magnitude. We find that the distribution of colors demonstrates a robust bimodality across the entire observed range of KBO sizes, from which we can categorize individual objects into two color sub-populations -- the red and very-red KBOs. We present the very first analysis of the magnitude distributions of the two color sub-populations.

A possible divot in the Kuiper belt's scattered-object size distribution

NASA Astrophysics Data System (ADS)

Shankman, C.; Kavelaars, J.; Gladman, B.; Petit, J.

2014-07-01

The formation and evolution history of the Solar System, while not directly accessible, has measurable signatures in the present-day size distributions of the Trans-Neptunian Object (TNO) populations. The form of the size distribution is modelled as a power law with number going as size to some characteristic slope. Recent works have shown that a single power law does not match the observations across all sizes; the power law breaks to a different form [1, 2, 3]. The large- size objects record the accretion history, while the small-size objects record the collision history. The changes of size-distribution shape and slope as one moves from 'large' to 'medium' to 'small' KBOs are the signature needed to constrain the formation and collision history of the Solar System. The scattering TNOs are those TNOs undergoing strong (scattering) interactions Neptune. The scattering objects can come to pericentre in the giant planet region. This close-in pericentre passage allows for the observation of smaller objects, and thus for the constraint of the small-size end of the size distribution. Our recent analysis of the Canada France Ecliptic Plane Survey's (CFEPS) scattering objects revealed an exciting potential form for the scattering object size distribution - a divot (see Figure). Our divot (a sharp drop in the number of objects per unit size which then returns at a potentially different slope) matches our observations well and can simultaneously explain observed features in other inclined (so-called "hot") Kuiper Belt populations. In this scenario all of the hot populations would share the same source and have been implanted in the outer solar system through scattering processes. If confirmed, our divot would represent a new exciting paradigm for the formation history of the Kuiper Belt. Here we present the results of an extension of our previous work to include a new, deeper, Kuiper Belt survey. By the addition of two new faint scattering objects from this survey which, in tandem with the full characterizations of the survey's biases (acting like non- detections limits), we better constrain the form of the scattering object size distribution.

The Whipple Mission: Exploring the Kuiper Belt and the Oort Cloud

NASA Astrophysics Data System (ADS)

Alcock, Charles; Brown, Michael; Gauron, Tom; Heneghan, Cate; Holman, Matthew; Kenter, Almus; Kraft, Ralph; Livingstone, John; Murray-Clay, Ruth; Nulsen, Paul; Payne, Matthew; Schlichting, Hilke; Trangsrud, Amy; Vrtilek, Jan; Werner, Michael

2015-11-01

Whipple will characterize the small body populations of the Kuiper Belt and the Oort Cloud with a blind occultation survey, detecting objects when they briefly (~1 second) interrupt the light from background stars, allowing the detection of much more distant and/or smaller objects than can be seen in reflected sunlight. Whipple will reach much deeper into the unexplored frontier of the outer solar system than any other mission, current or proposed. Whipple will look back to the dawn of the solar system by discovering its most remote bodies where primordial processes left their imprint.Specifically, Whipple will monitor large numbers of stars at high cadences (~12,000 stars at 20 Hz to examine Kuiper Belt events; as many as ~36,000 stars at 5 Hz to explore deep into the Oort Cloud, where events are less frequent). Analysis of the detected events will allow us to determine the size spectrum of bodies in the Kuiper Belt with radii as small as ~1 km. This will allow the testing of models of the growth and later collisional erosion of planetesimals in the early solar system. Whipple will explore the Oort Cloud, potentially detecting objects as far out as ~10,000 AU. This will be the first direct exploration of the Oort Cloud since the original hypothesis of 1950.Whipple is a Discovery class mission that was proposed to NASA in response to the 2014 Announcement of Opportunity. The mission is being developed jointly by the Smithsonian Astrophysical Observatory, Jet Propulsion Laboratories, and Ball Aerospace & Technologies, with telescope optics from L-3 Integrated Optical Systems and imaging sensors from Teledyne Imaging Sensors.

A giant impact origin of Pluto-Charon.

PubMed

Canup, Robin M

2005-01-28

Pluto and its moon, Charon, are the most prominent members of the Kuiper belt, and their existence holds clues to outer solar system formation processes. Here, hydrodynamic simulations are used to demonstrate that the formation of Pluto-Charon by means of a large collision is quite plausible. I show that such an impact probably produced an intact Charon, although it is possible that a disk of material orbited Pluto from which Charon later accumulated. These findings suggest that collisions between 1000-kilometer-class objects occurred in the early inner Kuiper belt.

Runaway Growth During Planet Formation: Explaining the Size Distribution of Large Kuiper Belt Objects

NASA Astrophysics Data System (ADS)

Schlichting, Hilke E.; Sari, Re'em

2011-02-01

Runaway growth is an important stage in planet formation during which large protoplanets form, while most of the initial mass remains in small planetesimals. The amount of mass converted into large protoplanets and their resulting size distribution are not well understood. Here, we use analytic work, that we confirm by coagulation simulations, to describe runaway growth and the corresponding evolution of the velocity dispersion. We find that runaway growth proceeds as follows. Initially, all the mass resides in small planetesimals, with mass surface density σ, and large protoplanets start to form by accreting small planetesimals. This growth continues until growth by merging large protoplanets becomes comparable to growth by planetesimal accretion. This condition sets in when Σ/σ ~ α3/4 ~ 10-3, where Σ is the mass surface density in protoplanets in a given logarithmic mass interval and α is the ratio of the size of a body to its Hill radius. From then on, protoplanetary growth and the evolution of the velocity dispersion become self-similar and Σ remains roughly constant, since an increase in Σ by accretion of small planetesimals is balanced by a decrease due to merging with large protoplanets. We show that this growth leads to a protoplanet size distribution given by N(>R) vprop R -3, where N(>R) is the number of objects with radii greater than R (i.e., a differential power-law index of 4). Since only the largest bodies grow significantly during runaway growth, Σ and thereby the size distribution are preserved. We apply our results to the Kuiper Belt, which is a relic of runaway growth where planet formation never proceeded to completion. Our results successfully match the observed Kuiper Belt size distribution, they illuminate the physical processes that shaped it and explain the total mass that is present in large Kuiper Belt objects (KBOs) today. This work suggests that the current mass in large KBOs is primordial and that it has not been significantly depleted. We also predict a maximum mass ratio for Kuiper Belt binaries that formed by dynamical processes of α-1/4 ~ 10, which explains the observed clustering in binary companion sizes that is seen in the cold classical belt. Finally, our results also apply to growth in debris disks, as long as frequent planetesimal-planetesimal collisions are not important during the growth.

Resonant and Secular Families of the Kuiper Belt

NASA Astrophysics Data System (ADS)

Chiang, E. I.; Lovering, J. R.; Millis, R. L.; Buie, M. W.; Wasserman, L. H.; Meech, K. J.

2003-06-01

We review ongoing efforts to identify occupants of mean-motion resonances (MMRs) and collisional families in the Edgeworth-Kuiper belt. Direct integrations of trajectories of Kuiper belt objects (KBOs) reveal the 1:1 (Trojan), 5:4, 4:3, 3:2 (Plutino), 5:3, 7:4, 9:5, 2:1 (Twotino), and 5:2 MMRs to be inhabited. Apart from the Trojan, resonant KBOs typically have large orbital eccentricities and inclinations. The observed pattern of resonance occupation is consistent with resonant capture and adiabatic excitation by a migratory Neptune; however, the dynamically cold initial conditions prior to resonance sweeping that are typically assumed by migration simulations are probably inadequate. Given the dynamically hot residents of the 5:2 MMR and the substantial inclinations observed in all exterior MMRs, a fraction of the primordial belt was likely dynamically pre-heated prior to resonance sweeping. A pre-heated population may have arisen as Neptune gravitationally scattered objects into trans-Neptunian space. The spatial distribution of Twotinos offers a unique diagnostic of Neptune's migration history. The Neptunian Trojan population may rival the Jovian Trojan population, and the former's existence is argued to rule out violent orbital histories for Neptune. Finally, lowest-order secular theory is applied to several hundred non-resonant KBOs with well-measured orbits to update proposals of collisional families. No convincing family is detected.

1998 SM165: A large Kuiper belt object with an irregular shape

PubMed Central

Romanishin, W.; Tegler, S. C.; Rettig, T. W.; Consolmagno, G.; Botthof, B.

2001-01-01

The recent discovery of an ancient reservoir of icy bodies at and beyond the orbit of Neptune—the Kuiper belt—has opened a new frontier in astronomy. Measurements of the physical and chemical nature of Kuiper belt objects (KBOs) can constrain our ideas of the processes of planet formation and evolution. Our 1.8-m Vatican Advanced Technology Telescope and charge-coupled device camera observations of the KBO 1998 SM165 indicate its brightness periodically varies by 0.56 magnitudes over a 4-h interval. If we assume a uniform albedo of 0.04, which is typical of values found in the literature for a handful of KBOs, and an “equator-on” aspect, we find 1998 SM165 has axes of length 600 × 360 km. If our assumptions are correct, such dimensions put 1998 SM165 among the largest elongated objects known in our solar system. Perhaps long ago, two nearly spherical KBOs of comparable size coalesced to form a compound object, or perhaps 1998 SM165 is the residual core of a catastrophic fragmentation of a larger precursor. PMID:11572937

THE ROTATION PERIOD AND LIGHT-CURVE AMPLITUDE OF KUIPER BELT DWARF PLANET 136472 MAKEMAKE (2005 FY9)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Heinze, A. N.; DeLahunta, Daniel

Kuiper Belt dwarf planet 136472 Makemake, formerly known as 2005 FY9, is currently the third-largest known object in the Kuiper Belt, after the dwarf planets Pluto and Eris. It is currently second only to Pluto in apparent brightness, due to Eris' much larger heliocentric distance. Makemake shows very little photometric variability, which has prevented confident determination of its rotation period until now. Using extremely precise time-series photometry, we find that the rotation period of Makemake is 7.7710 {+-} 0.0030 hr, where the uncertainty is a 90% confidence interval. An alias period is detected at 11.41 hr, but is determined withmore » approximately 95% confidence not to be the true period. Makemake's 7.77 hr rotation period is in the typical range for Kuiper Belt objects, consistent with Makemake's apparent lack of a substantial satellite to alter its rotation through tides. The amplitude of Makemake's photometric light curve is 0.0286 {+-} 0.0016 mag in V. This amplitude is about 10 times less than Pluto's, which is surprising given the two objects' similar sizes and spectral characteristics. Makemake's photometric variability is instead similar to that of Eris, which is so small that no confident rotation period has yet been determined. It has been suggested that dwarf planets such as Makemake and Eris, both farther from the Sun and colder than Pluto, exhibit lower photometric variability because they are covered with a uniform layer of frost. Such a frost is probably the correct explanation for Eris. However, it may be inconsistent with the spectrum of Makemake, which resembles reddish Pluto more than neutrally colored Eris. Makemake may instead be a more Pluto-like object that we observe at present with a nearly pole-on viewing geometry-a possibility that can be tested with continuing observations over the coming decades.« less

OSSOS: X. How to use a Survey Simulator: Statistical Testing of Dynamical Models Against the Real Kuiper Belt

NASA Astrophysics Data System (ADS)

Lawler, Samantha M.; Kavelaars, J. J.; Alexandersen, Mike; Bannister, Michele T.; Gladman, Brett; Petit, Jean-Marc; Shankman, Cory

2018-05-01

All surveys include observational biases, which makes it impossible to directly compare properties of discovered trans-Neptunian Objects (TNOs) with dynamical models. However, by carefully keeping track of survey pointings on the sky, detection limits, tracking fractions, and rate cuts, the biases from a survey can be modelled in Survey Simulator software. A Survey Simulator takes an intrinsic orbital model (from, for example, the output of a dynamical Kuiper belt emplacement simulation) and applies the survey biases, so that the biased simulated objects can be directly compared with real discoveries. This methodology has been used with great success in the Outer Solar System Origins Survey (OSSOS) and its predecessor surveys. In this chapter, we give four examples of ways to use the OSSOS Survey Simulator to gain knowledge about the true structure of the Kuiper Belt. We demonstrate how to statistically compare different dynamical model outputs with real TNO discoveries, how to quantify detection biases within a TNO population, how to measure intrinsic population sizes, and how to use upper limits from non-detections. We hope this will provide a framework for dynamical modellers to statistically test the validity of their models.

Layered Model for Radiation-Induced Chemical Evolution of Icy Surface Composition on Kuiper Belt and Oort Cloud Bodies

NASA Technical Reports Server (NTRS)

Cooper, John F.; Hill, Matthew E.; Richardson, John D.; Sturner, Steven J.

2010-01-01

The diversity of albedos and surface colors on observed Kuiper Belt and Inner Oort Cloud objects remains to be explained in terms of competition between primordial intrinsic versus exogenic drivers of surface and near-surface evolution. Earlier models have attempted without success to attribute this diversity to the relations between surface radiolysis from cosmic ray irradiation and gardening by meteoritic impacts. A more flexible approach considers the different depth-dependent radiation profiles produced by low-energy plasma, suprathermal, and maximally penetrating charged particles of the heliospheric and local interstellar radiation environments. Generally red objects of the dynamically cold (low inclination, circular orbit) Classical Kuiper Belt might be accounted for from erosive effects of plasma ions and reddening effects of high energy cosmic ray ions, while suprathermal keV-MeV ions could alternatively produce more color neutral surfaces. The deepest layer of more pristine ice can be brought to the surface from meter to kilometer depths by larger impact events and potentially by cryovolcanic activity. The bright surfaces of some larger objects, e.g. Eris, suggest ongoing resurfacing activity. Interactions of surface irradiation, resultant chemical oxidation, and near-surface cryogenic fluid reservoirs have been proposed to account for Enceladus cryovolcanism and may have further applications to other icy irradiated bodies. The diversity of causative processes must be understood to account for observationally apparent diversities of the object surfaces.

Layered Model for Radiation-Induced Chemical Evolution of Icy Surface Composition and Dynamics on Kuiper Belt and Oort Cloud Bodies

NASA Technical Reports Server (NTRS)

Cooper, John F.; Richardson, John D.

2010-01-01

The diversity of albedos and surface colors on observed Kuiper Belt and Inner Oort Cloud objects remains to be explained in terms of competition between primordial intrinsic versus exogenic drivers of surface and near-surface evolution. Earlier models have attempted without success to attribute this diversity to the relations between surface radiolysis from cosmic ray irradiation and gardening by meteoritic impacts. A more flexible approach considers the different depth-dependent radiation profiles produced by low-energy plasma, suprathermal, and maximally penetrating charged particles of the heliospheric and local interstellar radiation environment. Generally red objects of the dynamically cold (low inclination, circular orbit) Classical Kuiper Belt might be accounted for from erosive effects of plasma ions and reddening effects of high energy cosmic ray ions, while suprathermal keV-MeV ions could alternatively produce more color neutral surfaces. The deepest layer of more pristine ice can be brought to the surface from meter to kilometer depths by larger impact events and potentially by cryovolcanic activity. The bright surfaces of some larger objects, e.g. Eris, suggest ongoing resurfacing activity. Cycles of atmospheric formation and surface freezeout can further account for temporal variation as observed on Pluto. The diversity of causative processes must therefore be understood to account for observationally apparent diversities of the object surfaces.

Finding Kuiper Belt Objects Below the Detection Limit

NASA Astrophysics Data System (ADS)

Whidden, Peter; Kalmbach, Bryce; Bektesevic, Dino; Connolly, Andrew; Jones, Lynne; Smotherman, Hayden; Becker, Andrew

2018-01-01

We demonstrate a novel approach for uncovering the signatures of moving objects (e.g. Kuiper Belt Objects) below the detection thresholds of single astronomical images. To do so, we will employ a matched filter moving at specific rates of proposed orbits through a time-domain dataset. This is analogous to the better-known "shift-and-stack" method; however it uses neither direct shifting nor stacking of the image pixels. Instead of resampling the raw pixels to create an image stack, we will instead integrate the object detection probabilities across multiple single-epoch images to accrue support for a proposed orbit. The filtering kernel provides a measure of the probability that an object is present along a given orbit, and enables the user to make principled decisions about when the search has been successful, and when it may be terminated. The results we present here utilize GPUs to speed up the search by two orders of magnitudes over CPU implementations.

2007 TY430: A COLD CLASSICAL KUIPER BELT TYPE BINARY IN THE PLUTINO POPULATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheppard, Scott S.; Ragozzine, Darin; Trujillo, Chadwick, E-mail: sheppard@dtm.ciw.edu

2012-03-15

Kuiper Belt object 2007 TY430 is the first wide, equal-sized, binary known in the 3:2 mean motion resonance with Neptune. The two components have a maximum separation of about 1 arcsec and are on average less than 0.1 mag different in apparent magnitude with identical ultra-red colors (g - i = 1.49 {+-} 0.01 mag). Using nearly monthly observations of 2007 TY430 from 2007 to 2011, the orbit of the mutual components was found to have a period of 961.2 {+-} 4.6 days with a semi-major axis of 21000 {+-} 160 km and eccentricity of 0.1529 {+-} 0.0028. The inclinationmore » with respect to the ecliptic is 15.68 {+-} 0.22 deg and extensive observations have allowed the mirror orbit to be eliminated as a possibility. The total mass for the binary system was found to be 7.90 {+-} 0.21 Multiplication-Sign 10{sup 17} kg. Equal-sized, wide binaries and ultra-red colors are common in the low-inclination 'cold' classical part of the Kuiper Belt and likely formed through some sort of three-body interactions within a much denser Kuiper Belt. To date 2007 TY430 is the only ultra-red, equal-sized binary known outside of the classical Kuiper Belt population. Numerical simulations suggest 2007 TY430 is moderately unstable in the outer part of the 3:2 resonance and thus 2007 TY430 is likely an escaped 'cold' classical object that later got trapped in the 3:2 resonance. Similar to the known equal-sized, wide binaries in the cold classical population, the binary 2007 TY430 requires a high albedo and very low density structure to obtain the total mass found for the pair. For a realistic minimum density of 0.5 g cm{sup -3} the albedo of 2007 TY430 would be greater than 0.17. For reasonable densities, the radii of either component should be less than 60 km, and thus the relatively low eccentricity of the binary is interesting since no tides should be operating on the bodies at their large distances from each other. The low prograde inclination of the binary also makes it unlikely that the Kozai mechanism could have altered the orbit, making the 2007 TY430 binary orbit likely one of the few relatively unaltered primordial binary orbits known. Under some binary formation models, the low-inclination prograde orbit of the 2007 TY430 binary indicates formation within a relatively high velocity regime in the Kuiper Belt.« less

Distribution of Dust from Kuiper Belt Objects

NASA Technical Reports Server (NTRS)

Gorkavyi, Nick N.; Ozernoy, Leonid; Taidakova, Tanya; Mather, John C.; Fisher, Richard (Technical Monitor)

2000-01-01

Using an efficient computational approach, we have reconstructed the structure of the dust cloud in the Solar system between 0.5 and 100 AU produced by the Kuiper belt objects. Our simulations offer a 3-D physical model of the 'kuiperoidal' dust cloud based on the distribution of 280 dust particle trajectories produced by 100 known Kuiper belt objects; the resulting 3-D grid consists of 1.9 x 10' cells containing 1.2 x 10" particle positions. The following processes that influence the dust particle dynamics are taken into account: 1) gravitational scattering on the eight planets (neglecting Pluto); 2) planetary resonances; 3) radiation pressure; and 4) the Poynting-Robertson (P-R) and solar wind drags. We find the dust distribution highly non-uniform: there is a minimum in the kuiperoidal dust between Mars and Jupiter, after which both the column and number densities of kuiperoidal dust sharply increase with heliocentric distance between 5 and 10 AU, and then form a plateau between 10 and 50 AU. Between 25 and 45 AU, there is an appreciable concentration of kuiperoidal dust in the form of a broad belt of mostly resonant particles associated with Neptune. In fact, each giant planet possesses its own circumsolar dust belt consisting of both resonant and gravitationally scattered particles. As with the cometary belts simulated in our related papers, we reveal a rich and sophisticated resonant structure of the dust belts containing families of resonant peaks and gaps. An important result is that both the column and number dust density are more or less flat between 10 and 50 AU, which might explain the surprising data obtained by Pioneers 10 & 11 and Voyager that the dust number density remains approximately distance-independent in this region. The simulated kuiperoidal dust, in addition to asteroidal and cometary dust, might represent a third possible source of the zodiacal light in the Solar system.

The Outer Solar System Origins Survey: cold classicals beyond the 2:1 resonance

NASA Astrophysics Data System (ADS)

Bannister, Michele T.; Kavelaars, J. J.; Gladman, Brett; Petit, Jean-Marc; Gwyn, Stephen; Volk, Kathryn; Chen, Ying-Tung; Alexandersen, Mike

2015-11-01

With the 85 characterised discoveries from the first quarter of the ongoing Outer Solar System Origins Survey (OSSOS) with MegaPrime on the Canada-France-Hawaii Telescope, we find that the CFEPS L7 model of Petit et al. 2011 remains an accurate parameterization of the classical Kuiper belt's orbital structure, and the population estimate for the main belt remains unchanged (for 39 AU < a < 47 AU). We independently confirm the existence of substructure within the main classical Kuiper belt. The semi-major axis distribution of the stirred component of the cold classicals must contain a clumped ‘kernel’.We detect an extension of the cold classical Kuiper belt that continues at least several AU beyond the 2:1 mean motion resonance with Neptune. This extension would have strong cosmogonic implications for the origin of the classical belt's orbital substructure.We will discuss how the 140 new objects we discovered in the second quarter of OSSOS place further constraints on cold classicals beyond the 2:1 resonance. Our 16-18 month observational arcs and improved astrometric technique continue to achieve extremely high-quality measurements of TNO orbits: fractional semimajor axis uncertainties of our discoveries are consistently in the range 0.01-0.1%, allowing rapid orbital classification.

Impact and Cratering History of the Pluto System

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Gladman, Brett; McKinnon, William B.

2014-11-01

The observational opportunity of the New Horizons spacecraft fly-through of the Pluto system in July 2015 requires a current understanding of the Kuiper belt dynamical sub-populations to accurately interpret the cratering history of the surfaces of Pluto and its satellites. We use an Opik-style collision probability code to compute impact rates and impact velocity distributions onto Pluto and its binary companion Charon from the Canada-France Ecliptic Plane Survey (CFEPS) model of classical and resonant Kuiper belt populations (Petit et al., 2011; Gladman et al., 2012) and the scattering model of Kaib et al. (2011) calibrated to Shankman et al. (2013). Due to the uncertainty in how the well-characterized size distribution for Kuiper belt objects (with diameter d>100 km) connects to smaller objects, we compute cratering rates using three simple impactor size distribution extrapolations (a single power-law, a power-law with a knee, and a power-law with a divot) as well as the "curvy" impactor size distributions from Minton et al. (2012) and Schlichting et al. (2013). Current size distribution uncertainties cause absolute ages computed for Pluto surfaces to be entirely dependent on the extrapolation to small sizes and thus uncertain to a factor of approximately 6. We illustrate the relative importance of each Kuiper belt sub-population to Pluto's cratering rate, both now and integrated into the past, and provide crater retention ages for several cases. We find there is only a small chance a crater with diameter D>200 km has been created on Pluto in the past 4 Gyr. The 2015 New Horizons fly-through coupled with telescope surveys that cover objects with diameters d=10-100 km should eventually drop current crater retention age uncertainties on Pluto to <30%. In addition, we compute the "disruption timescale" (to a factor of three accuracy) for Pluto's smaller satellites: Styx, Nix, Kerberos, and Hydra.

The UT 7/8 February 2013 Sila-Nunam Mutual Event and Future Predictions

NASA Technical Reports Server (NTRS)

Benecchi, S. D.; Noll, K. S.; Thirouin, A.; Ryan, E.; Grundy, W. M.; Verbiscer, A.; Doressoundiram, A.; Hestroffer, D.; Beaton, R.; Rabinowitz, D.;

The Search for Planet Nine

NASA Astrophysics Data System (ADS)

Brown, Michael E.; Batygin, Konstantin

2016-10-01

We use an extensive suite of numerical simulations to constrain the mass and orbit of Planet Nine, and we use these constraints to begin the search for this newly proposed planet in new and in archival data. Here, we compare our simulations to the observed population of aligned eccentric high semimajor axis Kuiper belt objects and determine which simulation parameters are statistically compatible with the observations. We find that only a narrow range of orbital elements can reproduce the observations. In particular, the combination of semimajor axis, eccentricity, and mass of Planet Nine strongly dictates the semimajor axis range of the orbital confinement of the distant eccentric Kuiper belt objects. Allowed orbits, which confine Kuiper belt objects with semimajor axis beyond 380 AU, have perihelia roughly between 150 and 350 AU, semimajor axes between 380 and 980 AU, and masses between 5 and 20 Earth masses. Orbitally confined objects also generally have orbital planes similar to that of the planet, suggesting that the planet is inclined approximately 30 degrees to the ecliptic. We compare the allowed orbital positions and estimated brightness of Planet Nine to previous and ongoing surveys which would be sensitive to the planet's detection and use these surveys to rule out approximately two-thirds of the planet's orbit. Planet Nine is likely near aphelion with an approximate brightness of 22

The Trojan Color Conundrum

NASA Astrophysics Data System (ADS)

Jewitt, David

2018-02-01

The Trojan asteroids of Jupiter and Neptune are likely to have been captured from original heliocentric orbits in the dynamically excited (“hot”) population of the Kuiper Belt. However, it has long been known that the optical color distributions of the Jovian Trojans and the hot population are not alike. This difference has been reconciled with the capture hypothesis by assuming that the Trojans were resurfaced (for example, by sublimation of near-surface volatiles) upon inward migration from the Kuiper Belt (where blackbody temperatures are ∼40 K) to Jupiter’s orbit (∼125 K). Here, we examine the optical color distribution of the Neptunian Trojans using a combination of new optical photometry and published data. We find a color distribution that is statistically indistinguishable from that of the Jovian Trojans but unlike any sub-population in the Kuiper Belt. This result is puzzling, because the Neptunian Trojans are very cold (blackbody temperature ∼50 K) and a thermal process acting to modify the surface colors at Neptune’s distance would also affect the Kuiper Belt objects beyond, where the temperatures are nearly identical. The distinctive color distributions of the Jovian and Neptunian Trojans thus present us with a conundrum: they are very similar to each other, suggesting either capture from a common source or surface modification by a common process. However, the color distributions differ from any plausible common source population, and there is no known modifying process that could operate equally at both Jupiter and Neptune.

ALMA 1.3 Millimeter Map of the HD 95086 System -- A Young Analog of the HR 8799 System

NASA Astrophysics Data System (ADS)

Su, Kate; MacGregor, Meredith Ann; Booth, Mark; Wilner, David; Malhotra, Renu; Morrison, Sarah; OST STDT

2018-01-01

Planets and minor bodies such as asteroids, Kuiper-belt objects and comets are integral components of a planetary system. Interactions among them leave clues about the formation process of a planetary system. The signature of such interactions is best illustrated through resolved observations of its debris disk. Here we present ALMA 1.3 mm observations of HD 95086, a young analog of the HR 8799 system, that hosts a directly imaged giant planet b and a massive debris disk with both asteroid- and Kuiper-belt analogs. The location of the Kuiper-belt analog is resolved for the first time. Our deep ALMA map also reveals a bright source located near the edge of the ring. The properties of the source, based on limited data, are consistent with it being a luminous star-forming galaxy at high redshift. We will discuss future, resolved observations of debris disks, highlighting the potential of the Origins Space Telescope (OST), one of the four science and technology definition studies commissioned by NASA Headquarters for the 2020 Astronomy and Astrophysics Decadal survey.

Cold DUst around NEarby Stars (DUNES). First results. A resolved exo-Kuiper belt around the solar-like star ζ2 Ret

NASA Astrophysics Data System (ADS)

Eiroa, C.; Fedele, D.; Maldonado, J.; González-García, B. M.; Rodmann, J.; Heras, A. M.; Pilbratt, G. L.; Augereau, J.-Ch.; Mora, A.; Montesinos, B.; Ardila, D.; Bryden, G.; Liseau, R.; Stapelfeldt, K.; Launhardt, R.; Solano, E.; Bayo, A.; Absil, O.; Arévalo, M.; Barrado, D.; Beichmann, C.; Danchi, W.; Del Burgo, C.; Ertel, S.; Fridlund, M.; Fukagawa, M.; Gutiérrez, R.; Grün, E.; Kamp, I.; Krivov, A.; Lebreton, J.; Löhne, T.; Lorente, R.; Marshall, J.; Martínez-Arnáiz, R.; Meeus, G.; Montes, D.; Morbidelli, A.; Müller, S.; Mutschke, H.; Nakagawa, T.; Olofsson, G.; Ribas, I.; Roberge, A.; Sanz-Forcada, J.; Thébault, P.; Walker, H.; White, G. J.; Wolf, S.

2010-07-01

We present the first far-IR observations of the solar-type stars δ Pav, HR 8501, 51 Peg and ζ2 Ret, taken within the context of the DUNES Herschel open time key programme (OTKP). This project uses the PACS and SPIRE instruments with the objective of studying infrared excesses due to exo-Kuiper belts around nearby solar-type stars. The observed 100 μm fluxes from δ Pav, HR 8501, and 51 Peg agree with the predicted photospheric fluxes, excluding debris disks brighter than Ldust/Lstar 5 × 10-7 (1σ level) around those stars. A flattened, disk-like structure with a semi-major axis of 100 AU in size is detected around ζ2 Ret. The resolved structure suggests the presence of an eccentric dust ring, which we interpret as an exo-Kuiper belt with Ldust/Lstar ≈ 10-5. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.

New features in the structure of the classical Kuiper Belt

NASA Astrophysics Data System (ADS)

Gladman, Brett; Bannister, Michele T.; Alexandersen, Mike; Chen, Ying-Tung; Gwyn, Stephen; Kavelaars, J. J.; Petit, Jean-Marc; Volk, Kathryn; OSSOS Collaboration

2016-10-01

We report fascinating new dynamical structures emerging from a higher precision view of the classical Kuiper belt (the plentiful non-resonant orbits with semimajor axes in roughly the a=35-60 au range). The classical Kuiper Belt divides into multiple sub-populations: an 'inner' classical belt (a small group of non-resonant objects with a<39.4 au where the 3:2 resonance is located), an abundant 'main' classical belt (between the 3:2 and the 2:1 at a=47.4 au), and a difficult to study outer classical belt beyond the 2:1. We examine the dynamical structure, as precisely revealed in the detections from OSSOS (the Outer Solar System Origin's Survey); the data set is of superb quality in terms of orbital element and numbers of detections (Kavelaars et al, this meeting).The previous CFEPS survey showed that the main classical belt requires a complex dynamical substructure that goes beyond a simple 'hot versus cold' division based primarily on orbital inclination; the 'cold' inclination component requires two sub-components in the semimajor axis and perihelion distance q space (Petit et al 2011). CFEPS modelled this as a 'stirred' component present at all a=40-47 AU semimajor axes, with a dense superposed 'kernel' near a=44 AU at low eccentricity; the first OSSOS data release remained consistent with this (Bannister et al 2016). As with the main asteroid belt, as statistics and orbital quality improve we see additional significant substructure emerging in the classical belt's orbital distribution.OSSOS continues to add evidence that the cold stirred component extends smoothly beyond the 2:1 (Bannister et al 2016). Unexpectedly, the data also reveal the clear existence of a paucity of orbits just beyond the outer edge of the kernel; there are significantly fewer TNOs in the narrow semimajor axis band from a=44.5-45.0 AU. This may be related to the kernel population's creation, or it may be an independent feature created by planet migration as resonances moved in the primordial Kuiper Belt.

Tholins as Coloring Agents on Solar System Bodies

NASA Technical Reports Server (NTRS)

Cruikshank, D. P.; Ore, C. M. Dalle; Imanaka, H.

2004-01-01

Pre-biotic organic materials appear to be common on many small bodies in the outer Solar System, as evidenced by the color properties of these objects. We report on our continuing study of color properties in connection with the presence of complex organic solids (tholins) among the planets and their satellites, the asteroids, and the trans- Neptunian objects (Kuiper Belt objects). Most small, icy bodies in the Solar System, whether they have high or low surface reflectance (albedo), show a pronounced downward slope in reflectance at wavelengths shorter than approx. 1 micron. This increasing absorption of sunlight toward shorter wavelengths is characteristic of pi-bonds in hydrocarbons having chains or rings of conjugated C atoms. Tholins, which contain polycyclic aromatic and aliphatic hydrocarbons, exhibit these color properties. Using the complex refractive indices of tholins in models of the reflectance spectra of icy bodies in the Solar System, we find that these complex organic materials satisfactorily account for the coloration so widely observed. The new results presented here show that the wide variety of colors of Kuiper Belt objects can be fit very well with tholins, as can the colors of Pluto and Triton. The implications of these fits of Kuiper Belt objects is that complex organic material is created on their surfaces by energetic particle bombardment of native ices, and also may be accreted from external sources. In the cases of Pluto and Triton, photochemistry of their weak N2 + CH4 + CO atmospheres produces complex organic molecules that precipitate to the surface, providing local color.

Delayed Gratification Habitable Zones: When Deep Outer Solar System Regions Become Balmy During Post-Main Sequence Stellar Evolution

NASA Astrophysics Data System (ADS)

Stern, S. Alan

2003-06-01

Like all low- and moderate-mass stars, the Sun will burn as a red giant during its later evolution, generating of solar luminosities for some tens of millions of years. During this post-main sequence phase, the habitable (i.e., liquid water) thermal zone of our Solar System will lie in the region where Triton, Pluto-Charon, and Kuiper Belt objects orbit. Compared with the 1 AU habitable zone where Earth resides, this "delayed gratification habitable zone" (DGHZ) will enjoy a far less biologically hazardous environment - with lower harmful radiation levels from the Sun, and a far less destructive collisional environment. Objects like Triton, Pluto-Charon, and Kuiper Belt objects, which are known to be rich in both water and organics, will then become possible sites for biochemical and perhaps even biological evolution. The Kuiper Belt, with >105 objects >=50 km in radius and more than three times the combined surface area of the four terrestrial planets, provides numerous sites for possible evolution once the Sun's DGHZ reaches it. The Sun's DGHZ might be thought to only be of academic interest owing to its great separation from us in time. However, ~109 Milky Way stars burn as luminous red giants today. Thus, if icy-organic objects are common in the 20-50 AU zones of these stars, as they are in our Solar System (and as inferred in numerous main sequence stellar disk systems), then DGHZs may form a niche type of habitable zone that is likely to be numerically common in the Galaxy.

Delayed gratification habitable zones: when deep outer solar system regions become balmy during post-main sequence stellar evolution.

PubMed

Stern, S Alan

2003-01-01

Like all low- and moderate-mass stars, the Sun will burn as a red giant during its later evolution, generating of solar luminosities for some tens of millions of years. During this post-main sequence phase, the habitable (i.e., liquid water) thermal zone of our Solar System will lie in the region where Triton, Pluto-Charon, and Kuiper Belt objects orbit. Compared with the 1 AU habitable zone where Earth resides, this "delayed gratification habitable zone" (DGHZ) will enjoy a far less biologically hazardous environment - with lower harmful radiation levels from the Sun, and a far less destructive collisional environment. Objects like Triton, Pluto-Charon, and Kuiper Belt objects, which are known to be rich in both water and organics, will then become possible sites for biochemical and perhaps even biological evolution. The Kuiper Belt, with >10(5) objects > or =50 km in radius and more than three times the combined surface area of the four terrestrial planets, provides numerous sites for possible evolution once the Sun's DGHZ reaches it. The Sun's DGHZ might be thought to only be of academic interest owing to its great separation from us in time. However, approximately 10(9) Milky Way stars burn as luminous red giants today. Thus, if icy-organic objects are common in the 20-50 AU zones of these stars, as they are in our Solar System (and as inferred in numerous main sequence stellar disk systems), then DGHZs may form a niche type of habitable zone that is likely to be numerically common in the Galaxy.

The absolute magnitude distribution of cold classical Kuiper belt objects

NASA Astrophysics Data System (ADS)

Petit, Jean-Marc; Bannister, Michele T.; Alexandersen, Mike; Chen, Ying-Tung; Gladman, Brett; Gwyn, Stephen; Kavelaars, JJ; Volk, Kathryn

2016-10-01

We report measurements of the low inclination component of the main Kuiper Belt showing a size freqency distribution very steep for sizes larger than H_r ~ 6.5-7.0 and then a flattening to shallower slope that is still steeper than the collisional equilibrium slope.The Outer Solar System Origins Survey (OSSOS) is ongoing and is expected to detect over 500 TNOs in a precisely calibrated and characterized survey. Combining our current sample with CFEPS and the Alexandersen et al. (2015) survey, we analyse a sample of ~180 low inclination main classical (cold) TNOs, with absolute magnitude H_r (SDSS r' like flter) in the range 5 to 8.8. We confirm that the H_r distribution can be approximated by an exponential with a very steep slope (>1) at the bright end of the distribution, as has been recognized long ago. A transition to a shallower slope occurs around H_r ~ 6.5 - 7.0, an H_r mag identified by Fraster et al (2014). Faintward of this transition, we find a second exponential to be a good approximation at least until H_r ~ 8.5, but with a slope significantly steeper than the one proposed by Fraser et al. (2014) or even the collisional equilibrium value of 0.5.The transition in the cold TNO H_r distribution thus appears to occur at larger sizes than is observed in the high inclination main classical (hot) belt, an important indicator of a different cosmogony for these two sub-components of the main classical Kuiper belt. Given the largish slope faintward of the transition, the cold population with ~100 km diameter may dominate the mass of the Kuiper belt in the 40 AU < a < 47 au region.

Recovering Neptune 170 Years After its Initial Discovery

NASA Astrophysics Data System (ADS)

Myles, Justin

2017-01-01

Recent work by Trujillo and Shephard (2014) and Batygin and Brown (2016) has shown an as-yet unexplained clustering of the periapse vectors of the most distant Kuiper Belt objects. This unusual clustering has motivated the search for an unseen perturbing planet that is responsible for maintaining the alignment. As a proof of concept of a technique for locating unseen solar system planets, we use dynamical N-body integrations to simulate the orbital dynamics of distant Kuiper Belt objects, with the aim of determining the orbital parameters of Neptune (which, for the sake of exercise, we assume is, as-yet, undiscovered). In this poster, we determine the accuracy with which the perturbing planet’s orbital elements and sky location can be determined, and we show how the lessons learned can improve the search strategy for potentially undiscovered trans-Neptunian planets.

New Horizons: Long-Range Kuiper Belt Targets Observed by the Hubble Space Telescope

NASA Technical Reports Server (NTRS)

Benecchi, S. D.; Noll, K. S.; Weaver, H. A.; Spencer, J. R.; Stern, S. A.; Buie, M. W.; Parker, A. H.

2014-01-01

We report on Hubble Space Telescope (HST) observations of three Kuiper Belt Objects (KBOs), discovered in our dedicated ground-based search campaign, that are candidates for long-range observations from the New Horizons spacecraft: 2011 epochY31, 2011 HZ102, and 2013 LU35. Astrometry with HST enables both current and future critical accuracy improvements for orbit precision, required for possible New Horizons observations, beyond what can be obtained from the ground. Photometric colors of all three objects are red, typical of the Cold Classical dynamical population within which they reside; they are also the faintest KBOs to have had their colors measured. None are observed to be binary with HST above separations of approx. 0.02 arcsec (approx. 700 km at 44 AU) and delta m less than or equal to 0.5.

Formation of Kuiper-belt binaries through multiple chaotic scattering encounters with low-mass intruders

NASA Astrophysics Data System (ADS)

Astakhov, Sergey A.; Lee, Ernestine A.; Farrelly, David

2005-06-01

The discovery that many trans-Neptunian objects exist in pairs, or binaries, is proving invaluable for shedding light on the formation, evolution and structure of the outer Solar system. Based on recent systematic searches it has been estimated that up to 10 per cent of Kuiper-belt objects might be binaries. However, all examples discovered to date are unusual, as compared with near-Earth and main-belt asteroid binaries, for their mass ratios of the order of unity and their large, eccentric orbits. In this article we propose a common dynamical origin for these compositional and orbital properties based on four-body simulations in the Hill approximation. Our calculations suggest that binaries are produced through the following chain of events. Initially, long-lived quasi-bound binaries form by two bodies getting entangled in thin layers of dynamical chaos produced by solar tides within the Hill sphere. Next, energy transfer through gravitational scattering with a low-mass intruder nudges the binary into a nearby non-chaotic, stable zone of phase space. Finally, the binary hardens (loses energy) through a series of relatively gentle gravitational scattering encounters with further intruders. This produces binary orbits that are well fitted by Kepler ellipses. Dynamically, the overall process is strongly favoured if the original quasi-bound binary contains comparable masses. We propose a simplified model of chaotic scattering to explain these results. Our findings suggest that the observed preference for roughly equal-mass ratio binaries is probably a real effect; that is, it is not primarily due to an observational bias for widely separated, comparably bright objects. Nevertheless, we predict that a sizeable population of very unequal-mass Kuiper-belt binaries is probably awaiting discovery.

The Generation of the Distant Kuiper Belt by Planet Nine from an Initially Broad Perihelion Distribution

NASA Astrophysics Data System (ADS)

Khain, Tali; Batygin, Konstantin; Brown, Michael E.

2018-06-01

The observation that the orbits of long-period Kuiper Belt objects (KBOs) are anomalously clustered in physical space has recently prompted the Planet Nine hypothesis—the proposed existence of a distant and eccentric planetary member of our solar system. Within the framework of this model, a Neptune-like perturber sculpts the orbital distribution of distant KBOs through a complex interplay of resonant and secular effects, such that in addition to perihelion-circulating objects, the surviving orbits get organized into apsidally aligned and anti-aligned configurations with respect to Planet Nine’s orbit. In this work, we investigate the role of Kuiper Belt initial conditions on the evolution of the outer solar system using numerical simulations. Intriguingly, we find that the final perihelion distance distribution depends strongly on the primordial state of the system, and we demonstrate that a bimodal structure corresponding to the existence of both aligned and anti-aligned clusters is only reproduced if the initial perihelion distribution is assumed to extend well beyond ∼36 au. The bimodality in the final perihelion distance distribution is due to the existence of permanently stable objects, with the lower perihelion peak corresponding to the anti-aligned orbits and the higher perihelion peak corresponding to the aligned orbits. We identify the mechanisms that enable the persistent stability of these objects and locate the regions of phase space in which they reside. The obtained results contextualize the Planet Nine hypothesis within the broader narrative of solar system formation and offer further insight into the observational search for Planet Nine.

Checking the compatibility of the cold Kuiper belt with a planetary instability migration model

NASA Astrophysics Data System (ADS)

Gomes, Rodney; Nesvorný, David; Morbidelli, Alessandro; Deienno, Rogerio; Nogueira, Erica

2018-05-01

The origin of the orbital structure of the cold component of the Kuiper belt is still a hot subject of investigation. Several features of the solar system suggest that the giant planets underwent a phase of global dynamical instability, but the actual dynamical evolution of the planets during the instability is still debated. To explain the structure of the cold Kuiper belt, Nesvorny (2015, AJ 150,68) argued for a "soft" instability, during which Neptune never achieved a very eccentric orbit. Here we investigate the possibility of a more violent instability, from an initially more compact fully resonant configuration of 5 giant planets. We show that the orbital structure of the cold Kuiper belt can be reproduced quite well provided that the cold population formed in situ, with an outer edge between 44 - 45 au and never had a large mass.

(abstract) Sciencecraft

NASA Technical Reports Server (NTRS)

Beauchamp, P. M.; Brown, R. H.; Capps, R. W.; Rodgers, D. H.; Sercel, J.; Vane, G.; Soderblom, L. A.; Yelle, R. V.

1994-01-01

The technological capabilities are now at hand to design an integrated system that combines science instruments, spacecraft, and propulsion elements into a single system. The authors have called this a sciencecraft since it is intended to provide automatic scientific observations of planetary and astrophysical objects. Integration of function allows lower mass and cost and supports a short development cycle. A specific science mission is described in this paper, a flyby of Neptune, Triton, and an object in the Kuiper belt. The SCIENCECRAFT system is described. It has electric propulsion and is capable of measuring the surface constituents and morphology of objects visited and characterizing their atmospheres both in emission and adsorption (against the Sun). Miniature fields and particles experiments are incorporated that will provide interplanetary information together with details of the magnetic and electric attributes of each object. The Sciencecraft is Delta launched and has a flight time to the Kuiper belt of 7 years. The design is such that the craft functions in a largely autonomous mode to provide low cost mission operations.

The Outer Solar System Origins Survey. I. ; Design and First-Quarter Discoveries

NASA Technical Reports Server (NTRS)

Bannister, Michele T.; Kavelaars, J. J.; Petit, Jean-Marc; Gladman, Brett J.; Gwyn, Stephen D. J.; Chen, Ying-Tung; Volk, Kathryn; Alexandersen, Mike; Benecchi, Susan D.; Delsanti, Audrey;

The Outer Solar System Origins Survey (OSSOS): Survey Status and Highlights

NASA Astrophysics Data System (ADS)

Kavelaars, J. J.; Bannister, Michele T.; Alexandersen, Mike; Chen, Ying-Tung; Gladman, Brett; Gwyn, Stephen; Petit, Jean-Marc; Volk, Kathryn; OSSOS Collaboration

2016-10-01

We report the discovery, tracking and detection circumstances for 562 trans- Neptunian objects (TNOs) from the first 128 deg2 of the Outer Solar System Origins Survey (OSSOS). This ongoing r-band Solar System survey uses the ~1 deg2 field-of-view MegaPrime camera on the 3.6 m Canada-France-Hawaii Telescope. The orbital elements for these TNOs are precise to a fractional semi-major axis uncertainty of between 0.1 - 0.01%. We achieve this precision in just two oppositions, as compared to the normal 3--5 oppositions, via a dense observing cadence and innovative astrometric technique. These discoveries are free of ephemeris bias, a first for large trans-Neptunian surveys. Using the current OSSOS sample we confirm the existence of a cold "kernel" of objects within the main cold classical Kuiper belt, and infer the existence of an extension of the "stirred" cold classical Kuiper belt to at least several AU beyond the 2 :1 mean motion resonance with Neptune. We find that the population model of Petit et al. (2011) provides a plausible 1st order representation of the Kuiper belt, but more detailed structure has begun to emerged. The full survey, to be completed in 2017, will provide an exquisitely characterized sample of important resonant TNO populations, ideal for testing models of giant planet migration during the early history of the Solar System.

The Outer Solar System Origins Survey. I. Design and First-quarter Discoveries

NASA Astrophysics Data System (ADS)

Bannister, Michele T.; Kavelaars, J. J.; Petit, Jean-Marc; Gladman, Brett J.; Gwyn, Stephen D. J.; Chen, Ying-Tung; Volk, Kathryn; Alexandersen, Mike; Benecchi, Susan D.; Delsanti, Audrey; Fraser, Wesley C.; Granvik, Mikael; Grundy, Will M.; Guilbert-Lepoutre, Aurélie; Hestroffer, Daniel; Ip, Wing-Huen; Jakubik, Marian; Jones, R. Lynne; Kaib, Nathan; Kavelaars, Catherine F.; Lacerda, Pedro; Lawler, Samantha; Lehner, Matthew J.; Lin, Hsing Wen; Lister, Tim; Lykawka, Patryk Sofia; Monty, Stephanie; Marsset, Michael; Murray-Clay, Ruth; Noll, Keith S.; Parker, Alex; Pike, Rosemary E.; Rousselot, Philippe; Rusk, David; Schwamb, Megan E.; Shankman, Cory; Sicardy, Bruno; Vernazza, Pierre; Wang, Shiang-Yu

2016-09-01

We report the discovery, tracking, and detection circumstances for 85 trans-Neptunian objects (TNOs) from the first 42 deg2 of the Outer Solar System Origins Survey. This ongoing r-band solar system survey uses the 0.9 deg2 field of view MegaPrime camera on the 3.6 m Canada-France-Hawaii Telescope. Our orbital elements for these TNOs are precise to a fractional semimajor axis uncertainty <0.1%. We achieve this precision in just two oppositions, as compared to the normal three to five oppositions, via a dense observing cadence and innovative astrometric technique. These discoveries are free of ephemeris bias, a first for large trans-Neptunian surveys. We also provide the necessary information to enable models of TNO orbital distributions to be tested against our TNO sample. We confirm the existence of a cold “kernel” of objects within the main cold classical Kuiper Belt and infer the existence of an extension of the “stirred” cold classical Kuiper Belt to at least several au beyond the 2:1 mean motion resonance with Neptune. We find that the population model of Petit et al. remains a plausible representation of the Kuiper Belt. The full survey, to be completed in 2017, will provide an exquisitely characterized sample of important resonant TNO populations, ideal for testing models of giant planet migration during the early history of the solar system.

Centaurs and Activity Beyond the Water Sublimation Zone

NASA Astrophysics Data System (ADS)

Jewitt, David

2017-08-01

Centaurs are icy objects in dynamical transition between the Kuiper belt, where they originate, and the Jupiter family comets. Water ice in inward drifting Centaurs should begin to sublimate measurably when their perihelion reaches the orbit of Jupiter (5 AU). Instead, a fraction of Centaurs become active (have a cometary appearance) even with perihelia at Saturn (10 AU). Of the many suggestions made for the origin of this distant activity, the current favorite and the one with the largest impact on cometary science is the crystallization of amorphous water ice. Amorphous ice is an excellent carrier of supervolatiles (e.g. CO, N2) which are released upon the exothermic transition to crystalline ice. If Centaur ice is amorphous, then so must be Kuiper belt ice, setting strong constraints on the internal temperature vs. time history of the Kuiper belt objects. If the crystallization hypothesis is correct, we should never find an active Centaur with a perihelion substantially beyond the so-called crystallization line at about 12 AU (because temperatures there are too low to trigger crystallization). We propose a simple search for distant activity in Centaurs with perihelia 15 to 20 AU, in which crystallization cannot occur, in order to challenge the crystallization hypothesis. The search is made possible by the tight and stable point spread function and sensitivity to near-nucleus coma of HST.

The scattered disk and hot belt, two sides of the same coin?

NASA Astrophysics Data System (ADS)

Kavelaars, J. J.; Petit, J.-M.; Gladman, B.; Jone, R. L.; Parker, J.; Taylor, M.

2011-10-01

The Canada-France Ecliptic Plane Survey (CFEPS) and High Latitude Extension (HILat)[] obtained characterized observations of nearly 800 sq.deg. of sky to depths in the range ˜23.5 - 24.4 AB mag, providing a database of nearly 200 trans-neptunian objects (TNOs) with high-precision dynamical classification and known discovery efficiency. Using this database, we find that the high-inclination component of the inner (a < 40 AU) main (a=40-47 AU) classical and outer (a > 47 AU) belt are well represented by a continuous density distribution coming from a constrained q range (35 < q < 40). This range of peri-center is similar to the range which some researchers associated with the scattered disk. In our modeling of the orbital phase space of the Kuiper belt we find that there is no need for two distinct components (ie. both a scattered disk and a hot component to the classical belt). The historical separation of the high-inclination component of the Kuiper belt into these two distinct structures appears to have been mis-guided.

COLLISIONAL EVOLUTION OF ULTRA-WIDE TRANS-NEPTUNIAN BINARIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, Alex H.; Kavelaars, J. J., E-mail: alexhp@uvic.ca

2012-01-10

The widely separated, near-equal mass binaries hosted by the cold classical Kuiper Belt are delicately bound and subject to disruption by many perturbing processes. We use analytical arguments and numerical simulations to determine their collisional lifetimes given various impactor size distributions and include the effects of mass loss and multiple impacts over the lifetime of each system. These collisional lifetimes constrain the population of small (R {approx}> 1 km) objects currently residing in the Kuiper Belt and confirm that the size distribution slope at small size cannot be excessively steep-likely q {approx}< 3.5. We track mutual semimajor axis, inclination, andmore » eccentricity evolution through our simulations and show that it is unlikely that the wide binary population represents an evolved tail of the primordially tight binary population. We find that if the wide binaries are a collisionally eroded population, their primordial mutual orbit planes must have preferred to lie in the plane of the solar system. Finally, we find that current limits on the size distribution at small radii remain high enough that the prospect of detecting dust-producing collisions in real time in the Kuiper Belt with future optical surveys is feasible.« less

A study of binary Kuiper belt objects

NASA Astrophysics Data System (ADS)

Kern, Susan Diane

2006-06-01

About 10 5 bodies larger than 100km in diameter (Jewitt 1998) reside in the Kuiper Belt, beyond the orbit of Neptune. Since 1992 observational surveys have discovered over one thousand of these objects, believed to be fossil remnants of events that occurred nearly 4.5 billion years ago. Sixteen of these objects are currently known to be binaries, and many more are expected to be discovered. As part of the Deep Ecliptic Survey (DES) I have helped catalog nearly one third of the known Kuiper Belt object (KBO) population, and used that database for further physical studies. Recovery observations for dynamical studies of newly discovered objects with the Magellan telescopes and a high resolution imager, MagIC, revealed three binaries, 88611 (2001QT297), 2003QY90, and 2005EO304. One binary was found in the discovery observations, 2003UN284. Lightcurve measurements of these, and other non-binary KBOs, were obtained to look for unique rotational characteristics. Eleven of thirty-three objects, excluding the binaries, were found to have measurable variability. One of these objects, 2002GW32 has a particularly large amplitude (> 1 magnitude) of variability, and 2002GP32 has a relatively short (~3.3 hours, single-peaked) lightcurve. Among the binary population all the observed objects showed some level of variation. The secondary of 88611 was fit with a single-peaked period of 5.5±0.02 hours while the primary component appears to be non-variable above the measurement errors (0.05 magnitudes). Neither component appears to be color variable. The components of 2003QY90 are both highly variable yielding single- peaked rotation periods of 3.5±1.1 and 7.2±2.9 hours with amplitudes of 0.34±0.06 and 0.90±0.18 magnitudes, respectively. The rotation periods are comparable to those of other non-binary KBOs although distinct from that of an identified contact binary. Orbits and partial orbits for Kuiper belt binaries (KBBs) show a wide range of eccentricities, and an increasing number of binaries with decreasing binary semi-major axis. These characteristics exclude the formation models proposed by Funato et al. (2003) and Weidenschilling (2002), respectively. Conversely, the formation models of Astakhov et al. (2005) and Goldreich et al. (2002) appear to describe the observations, at least in part. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)

THE TAOS PROJECT: RESULTS FROM SEVEN YEARS OF SURVEY DATA

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhang, Z.-W.; Lehner, M. J.; Wang, J.-H.

2013-07-01

The Taiwanese-American Occultation Survey (TAOS) aims to detect serendipitous occultations of stars by small ({approx}1 km diameter) objects in the Kuiper Belt and beyond. Such events are very rare (<10{sup -3} events per star per year) and short in duration ({approx}200 ms), so many stars must be monitored at a high readout cadence. TAOS monitors typically {approx}500 stars simultaneously at a 5 Hz readout cadence with four telescopes located at Lulin Observatory in central Taiwan. In this paper, we report the results of the search for small Kuiper Belt objects (KBOs) in seven years of data. No occultation events weremore » found, resulting in a 95% c.l. upper limit on the slope of the faint end of the KBO size distribution of q = 3.34-3.82, depending on the surface density at the break in the size distribution at a diameter of about 90 km.« less

A Comparative Planetology Activity

ERIC Educational Resources Information Center

LoPresto, Michael C.; Murrell, Steven R.

2010-01-01

The beginning of a typical solar system "unit" in a traditional introductory astronomy course often consists of an overview of the different object types--planets, moons, and debris (asteroids, comets, and meteors), and now also Pluto's home, the Kuiper belt--prior to coverage of formation and more detail about the various object types. An…

Migration of Matter from the Edgeworth-Kuiper and Main Asteroid Belts to the Earth

NASA Technical Reports Server (NTRS)

Ipatov. S. I.; Oegerle, William (Technical Monitor)

2002-01-01

The main asteroid belt (MAB), the Edgeworth-Kuiper belt (EKB), and comets belong to the main sources of dust in the Solar System. Most of Jupiter-family comets came from the EKB. Comets can be distracted due to close encounters with planets and the Sun, collisions with small bodies, a nd internal forces. We support the Eneev's idea that the largest objects in the ELB and MAB could be formed directly by the compression of rarefied dust condensations of the protoplanetary cloud but not by the accretion of small (for example, 1-km) planetesimals. The total mass of planetesimals that entered the EKB from the feeding zone of the giant planets during their accumulation could exceed tens of Earth's masses. These planetesimals increased eccentricities of 'local' trans-Neptunian objects (TNOs) and swept most of these TNOs. A small portion of such planetesimals could left beyond Neptune's orbit in highly eccentric orbits. The results of previous investigations of migration and collisional evolution of minor bodies were summarized. Mainly our recent results are presented.

Resonance Occupation in the Kuiper Belt: Case Examples of the 5:2 and Trojan Resonances

NASA Astrophysics Data System (ADS)

Chiang, E. I.; Jordan, A. B.; Millis, R. L.; Buie, M. W.; Wasserman, L. H.; Elliot, J. L.; Kern, S. D.; Trilling, D. E.; Meech, K. J.; Wagner, R. M.

2003-07-01

As part of our ongoing Deep Ecliptic Survey (DES) of the Kuiper belt, we report on the occupation of the 1:1 (Trojan), 4:3, 3:2, 7:4, 2:1, and 5:2 Neptunian mean motion resonances (MMRs). The previously unrecognized occupation of the 1:1 and 5:2 MMRs is not easily understood within the standard model of resonance sweeping by a migratory Neptune over an initially dynamically cold belt. Among all resonant Kuiper belt objects (KBOs), the three observed members of the 5:2 MMR discovered by DES possess the largest semimajor axes (a~55.4 AU), the highest eccentricities (e~0.4), and substantial orbital inclinations (i~10deg). Objects (38084) 1999HB12 and possibly 2001KC77 can librate with modest amplitudes of ~90° within the 5:2 MMR for at least 1 Gyr. Their trajectories cannot be explained by close encounters with Neptune alone, given the latter's current orbit. The dynamically hot orbits of such 5:2 resonant KBOs, unlike hot orbits of previously known resonant KBOs, may imply that these objects were preheated to large inclination and large eccentricity prior to resonance capture by a migratory Neptune. Our first discovered Neptunian Trojan, 2001QR322, may not owe its existence to Neptune's migration at all. The trajectory of 2001QR322 is remarkably stable; the object can undergo tadpole-type libration about Neptune's leading Lagrange (L4) point for at least 1 Gyr with a libration amplitude of 24°. Trojan capture probably occurred while Neptune accreted the bulk of its mass. For an assumed albedo of 12%-4%, our Trojan is ~130-230 km in diameter. Model-dependent estimates place the total number of Neptune Trojans resembling 2001QR322 at ~20-60. Their existence helps to rule out violent orbital histories for Neptune.

Interpretation of the Near-IR Spectra of the Kuiper Belt Object

NASA Technical Reports Server (NTRS)

Eluszkiewicz, Janusz; Cady-Pereira, Karen; Brown, Michael E.; Stansberry, John A.

2007-01-01

Visible and near-IR observations of the Kuiper Belt Object (136472) 2005 FY(9) have indicated the presence of unusually long (1 cm or more) optical path lengths in a layer of methane ice. Using microphysical and radiative transfer modeling, we show that even at the frigid temperatures in the outer reaches of the solar system, a slab of low porosity methane ice can indeed form by pressureless sintering of micron-sized grains, and it can qualitatively reproduce the salient features of the measured spectra. A good semiquantitative match with the near-IR spectra can be obtained with a realistic slab model, provided the spectra are scaled to a visible albedo of 0.6, at the low end of the values currently estimated from Spitzer thermal measurements. Consistent with previous modeling studies, matching spectra scaled to higher albedos requires the incorporation of strong backscattering effects. The albedo may become better constrained through an iterative application of the slab model to the analysis of the thermal measurements from Spitzer and the visible/near-IR reflectance spectra. The slab interpretation offers two falsifiable predictions (1) Absence of an opposition surge, which is commonly attributed to the fluffiness of the optical surface. This prediction is best testable with a spacecraft, as Earth-based observations at true opposition will not be possible until early next century. (2) Unlikelihood of the simultaneous occurrence of very long spectroscopic path lengths in both methane and nitrogen ice on the surface of any Kuiper Belt Object, as the more volatile nitrogen would hinder densification in methane ice.

New Horizons Encountering 2014 MU69 (Artist's Impression)

NASA Image and Video Library

2018-01-04

Artist's impression of NASA's New Horizons spacecraft encountering 2014 MU69, a Kuiper Belt object that orbits one billion miles (1.6 billion kilometers) beyond Pluto, on Jan. 1, 2019. https://photojournal.jpl.nasa.gov/catalog/PIA22190

CHARACTERIZATION OF SEVEN ULTRA-WIDE TRANS-NEPTUNIAN BINARIES

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, Alex H.; Kavelaars, J. J.; Petit, Jean-Marc

2011-12-10

The low-inclination component of the Classical Kuiper Belt is host to a population of extremely widely separated binaries. These systems are similar to other trans-Neptunian binaries (TNBs) in that the primary and secondary components of each system are of roughly equal size. We have performed an astrometric monitoring campaign of a sample of seven wide-separation, long-period TNBs and present the first-ever well-characterized mutual orbits for each system. The sample contains the most eccentric (2006 CH{sub 69}, e{sub m} = 0.9) and the most widely separated, weakly bound (2001 QW{sub 322}, a/R{sub H} {approx_equal} 0.22) binary minor planets known, and alsomore » contains the system with lowest-measured mass of any TNB (2000 CF{sub 105}, M{sub sys} {approx_equal} 1.85 Multiplication-Sign 10{sup 17} kg). Four systems orbit in a prograde sense, and three in a retrograde sense. They have a different mutual inclination distribution compared to all other TNBs, preferring low mutual-inclination orbits. These systems have geometric r-band albedos in the range of 0.09-0.3, consistent with radiometric albedo estimates for larger solitary low-inclination Classical Kuiper Belt objects, and we limit the plausible distribution of albedos in this region of the Kuiper Belt. We find that gravitational collapse binary formation models produce an orbital distribution similar to that currently observed, which along with a confluence of other factors supports formation of the cold Classical Kuiper Belt in situ through relatively rapid gravitational collapse rather than slow hierarchical accretion. We show that these binary systems are sensitive to disruption via collisions, and their existence suggests that the size distribution of TNOs at small sizes remains relatively shallow.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jewitt, David, E-mail: jewitt@ucla.edu

Most comets are volatile-rich bodies that have recently entered the inner solar system following long-term storage in the Kuiper belt and the Oort cloud reservoirs. These reservoirs feed several distinct, short-lived “small body” populations. Here, we present new measurements of the optical colors of cometary and comet-related bodies including long-period (Oort cloud) comets, Damocloids (probable inactive nuclei of long-period comets) and Centaurs (recent escapees from the Kuiper belt and precursors to the Jupiter family comets). We combine the new measurements with published data on short-period comets, Jovian Trojans and Kuiper belt objects to examine the color systematics of the comet-relatedmore » populations. We find that the mean optical colors of the dust in short-period and long-period comets are identical within the uncertainties of measurement, as are the colors of the dust and of the underlying nuclei. These populations show no evidence for scattering by optically small particles or for compositional gradients, even at the largest distances from the Sun, and no evidence for ultrared matter. Consistent with earlier work, ultrared surfaces are common in the Kuiper belt and on the Centaurs, but not in other small body populations, suggesting that this material is hidden or destroyed upon entry to the inner solar system. The onset of activity in the Centaurs and the disappearance of the ultrared matter in this population begin at about the same perihelion distance (∼10 AU), suggesting that the two are related. Blanketing of primordial surface materials by the fallback of sub-orbital ejecta, for which we calculate a very short timescale, is the likely mechanism. The same process should operate on any mass-losing body, explaining the absence of ultrared surface material in the entire comet population.« less

Making the cold Kuiper belt in a planetary instability migration model

NASA Astrophysics Data System (ADS)

Gomes, Rodney S.

2017-06-01

Numerical integrations of the equations of motion of Jupiter, Saturn, three ice cores and a disk of planetesimals are undertaken. Two of the ice planets stand for Uranus and Neptune and a third one is expected to be ejected from the solar system. The planets start in compact cold orbits and each one is in mean motion resonance with its neighbor(s). The disk of planetesimals is placed just outside the outermost planet and is extended to 45 au. Five hundred integrations are done for each of four masses assigned to the disk, which are 25, 30, 35 and 40 Earth masses. The integrations are extended to 100 My. After that, I choose the successful runs in which there are four planets left in closed orbits around the Sun and I separate the good runs among the successful ones, defined by semi-major axes ranges around and not too far from the real ones. Among these good runs, I further choose by visual inspection those that yield an orbital distribution of planetesimals at the Kuiper belt region that resembles the real cold Kuiper belt. I extend these runs to 1 Gy and, after that, to 4.5 Gy. These last integrations for 3.5 Gy are done after replacing the orbits of the planets in the end of the 1 Gy integrations by their current orbits, changing the semi-major axes of the planetesimals so as to keep the same mean motion ratio with Neptune and assigning null masses for the planetesimals. Orbital distributions of the cold Kuiper belt obtained in some of the runs at 4.5 Gy are quite similar to that of the real cold Kuiper belt. The mass in the Kuiper belt region can be dynamically eroded to up to 90% of the original mass. The main conclusion is that the cold Kuiper belt is compatible with a past planetary instability phase even though in some of these runs Neptune's semi-major axis and eccentricity attained values simultaneously larger than 20 au and 0.2 for over 1 My.

The future of Stardust science

NASA Astrophysics Data System (ADS)

Westphal, A. J.; Bridges, J. C.; Brownlee, D. E.; Butterworth, A. L.; de Gregorio, B. T.; Dominguez, G.; Flynn, G. J.; Gainsforth, Z.; Ishii, H. A.; Joswiak, D.; Nittler, L. R.; Ogliore, R. C.; Palma, R.; Pepin, R. O.; Stephan, T.; Zolensky, M. E.

2017-09-01

Recent observations indicate that >99% of the small bodies in the solar system reside in its outer reaches—in the Kuiper Belt and Oort Cloud. Kuiper Belt bodies are probably the best-preserved representatives of the icy planetesimals that dominated the bulk of the solid mass in the early solar system. They likely contain preserved materials inherited from the protosolar cloud, held in cryogenic storage since the formation of the solar system. Despite their importance, they are relatively underrepresented in our extraterrestrial sample collections by many orders of magnitude ( 1013 by mass) as compared with the asteroids, represented by meteorites, which are composed of materials that have generally been strongly altered by thermal and aqueous processes. We have only begun to scratch the surface in understanding Kuiper Belt objects, but it is already clear that the very limited samples of them that we have in our laboratories hold the promise of dramatically expanding our understanding of the formation of the solar system. Stardust returned the first samples from a known small solar system body, the Jupiter-family comet 81P/Wild 2, and, in a separate collector, the first solid samples from the local interstellar medium. The first decade of Stardust research resulted in more than 142 peer-reviewed publications, including 15 papers in Science. Analyses of these amazing samples continue to yield unexpected discoveries and to raise new questions about the history of the early solar system. We identify nine high-priority scientific objectives for future Stardust analyses that address important unsolved problems in planetary science.

Finding KBO flyby targets for New Horizons

NASA Astrophysics Data System (ADS)

Spencer, John; Trilling, David; Buie, Marc; Parker, Alex; Tholen, David; Stern, S. Alan

2014-08-01

We propose to continue the search for Kuiper Belt Objects (KBOs) that can be reached by the New Horizons spacecraft after its 2015 Pluto flyby, by following up on KBOs discovered in 2014A. The first flyby of a small (~50 km) KBO would revolutionize our understanding of KBOs, providing information that can be extrapolated to hundreds of thousands of similar KBOs. Our 2011 search discovered two objects that could be targeted with less than twice the fuel that New Horizons has available, during excellent seeing, but seeing was insufficient to achieve this depth over the entire search area in 2012 or 2013. Deepening the search with time allocated in 2014A, taking advantage of lower star density and the shrinking search area, has a chance of finding a targetable object given sufficiently good seeing, especially with Hyper Suprime Cam. 2014B follow-up is essential to produce orbits good enough to determine targetability, and allow recovery in 2015. We will also continue to refine the orbits of other previously discovered objects, including ones that can be observed from a distance by New Horizons on its passage through the Kuiper Belt.

The Structure of the Distant Kuiper Belt in a Nice Model Scenario

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pike, R. E.; Shankman, C. J.; Kavelaars, J. J.

2017-03-01

This work explores the orbital distribution of minor bodies in the outer Solar System emplaced as a result of a Nice model migration from the simulations of Brasser and Morbidelli. This planetary migration scatters a planetesimal disk from between 29 and 34 au and emplaces a population of objects into the Kuiper Belt region. From the 2:1 Neptune resonance and outward, the test particles analyzed populate the outer resonances with orbital distributions consistent with trans-Neptunian object (TNO) detections in semimajor axis, inclination, and eccentricity, while capture into the closest resonances is too efficient. The relative populations of the simulated scatteringmore » objects and resonant objects in the 3:1 and 4:1 resonances are also consistent with observed populations based on debiased TNO surveys, but the 5:1 resonance is severely underpopulated compared to population estimates from survey results. Scattering emplacement results in the expected orbital distribution for the majority of the TNO populations; however, the origin of the large observed population in the 5:1 resonance remains unexplained.« less

Hubble Witnesses Massive Comet-Like Object Pollute Atmosphere of a White Dwarf

NASA Image and Video Library

2017-12-08

For the first time, scientists using NASA’s Hubble Space Telescope have witnessed a massive object with the makeup of a comet being ripped apart and scattered in the atmosphere of a white dwarf, the burned-out remains of a compact star. The object has a chemical composition similar to Halley’s Comet, but it is 100,000 times more massive and has a much higher amount of water. It is also rich in the elements essential for life, including nitrogen, carbon, oxygen, and sulfur. These findings are evidence for a belt of comet-like bodies orbiting the white dwarf, similar to our solar system’s Kuiper Belt. These icy bodies apparently survived the star’s evolution as it became a bloated red giant and then collapsed to a small, dense white dwarf. Caption: This artist's concept shows a massive, comet-like object falling toward a white dwarf. New Hubble Space Telescope findings are evidence for a belt of comet-like bodies orbiting the white dwarf, similar to our solar system's Kuiper Belt. The findings also suggest the presence of one or more unseen surviving planets around the white dwarf, which may have perturbed the belt to hurl icy objects into the burned-out star. Credits: NASA, ESA, and Z. Levay (STScI) NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

Exploration at the Edge of the Solar System: The Pluto-Kuiper Express Mission (Invited)

NASA Astrophysics Data System (ADS)

Terrile, R. J.

1999-09-01

The Pluto-Kuiper Express mission is one component of the Outer Planets/Solar Probe Project which is part of the exploration strategy laid out in the Solar System Exploration Roadmap. The first three missions of this project are the Europa Orbiter, Pluto-Kuiper Express and the Solar Probe. All require challenging new technologies and the ability to operate in deep space and at Jupiter. Use of common management and design approaches, avionics, and mission software is planned to reduce the costs of the three missions. The Pluto-Kuiper Express mission is planned to launch in 2004 and is designed to provide the first reconnaissance of the Solar System's most distant planet, Pluto, and it, moon Charon. A gravity assist from Jupiter will allow an 8-year flight time to Pluto and the possibility of encountering one or more Edgeworth-Kuiper Belt objects after the Pluto encounter. The primary science objectives for the mission include characterizing the global geology and geomorphology of Pluto and Charon, mapping their surface composition and characterizing Pluto's neutral atmosphere and its escape rate. This mission is currently soliciting scientific investigations through a NASA Announcement of Opportunity.

OORT-Cloud and Kuiper-Belt Comets

NASA Technical Reports Server (NTRS)

Whipple, Fred L.

1998-01-01

This paper follows the broadly accepted theory that Oort-Cloud Comets originated in the Solar Nebula in the general region where the major planets, Jupiter and Saturn, were formed while the Kuiper-Belt Comets originated farther out where the temperatures were lower. The Oort-Cloud Comets are identified orbitally by long periods and random inclinations and, including the Halley-type comets, comets with a Tisserand Criterion less than 2.0. Kuiper-Belt comets are identified by short periods, usually much less than 200 years, and small inclinations to the ecliptic. Here two criteria for comet activity are found to separate the two classes of comets. These quantities NG1 and NG2, were intended to measure theoretical nongravitaional effects on comet orbits. They are only, mildly successful in correlations with observed cases of measured non-gravitational forces. But, in fact, their variations with perihelion distance separate the two classes of comets. The results are consistent with the theory that the activity or intrinsic brightness of Oort-Cloud Comets fall off faster with increasing perihelion distance that does the intrinsic brightness of short-period Kuiper-Belt Comets.

Meteoritic Evidence for Injection of Trans-Neptunian Objects into the Inner Solar System

NASA Technical Reports Server (NTRS)

Zolensky, M.; Johnson, J.; Ziegler, K.; Chan, Q.; Kebukawa, Y.; Bottke, W.; Fries, M.; Martinez, J.; Le, L.

2018-01-01

There is excellent evidence that a dynamical instability in the early solar system led to gravitational interactions between the giant planets and trans-Neptunian planetesimals. Giant planetary migration triggered by the instability dispersed a disk of primordial trans-Neptunian object (TNOs) and created a number of small body reservoirs (e.g. the Kuiper Belt, scattered disk, irregular satellites, and the Jupiter/Neptune Trojan populations). It also injected numerous bodies into the main asteroid belt, where modeling shows they can successfully reproduce the observed P and D-type asteroid populations.

NASA’s Hubble Telescope Finds Potential Kuiper Belt Targets for New Horizons Pluto Mission

NASA Image and Video Library

2017-12-08

This is an artist’s impression of a Kuiper Belt object (KBO), located on the outer rim of our solar system at a staggering distance of 4 billion miles from the Sun. A HST survey uncovered three KBOs that are potentially reachable by NASA’s New Horizons spacecraft after it passes by Pluto in mid-2015. Credit: NASA, ESA, and G. Bacon (STScI) --- Peering out to the dim, outer reaches of our solar system, NASA’s Hubble Space Telescope has uncovered three Kuiper Belt objects (KBOs) the agency’s New Horizons spacecraft could potentially visit after it flies by Pluto in July 2015. The KBOs were detected through a dedicated Hubble observing program by a New Horizons search team that was awarded telescope time for this purpose. “This has been a very challenging search and it’s great that in the end Hubble could accomplish a detection – one NASA mission helping another,” said Alan Stern of the Southwest Research Institute (SwRI) in Boulder, Colorado, principal investigator of the New Horizons mission. The Kuiper Belt is a vast rim of primordial debris encircling our solar system. KBOs belong to a unique class of solar system objects that has never been visited by spacecraft and which contain clues to the origin of our solar system. The KBOs Hubble found are each about 10 times larger than typical comets, but only about 1-2 percent of the size of Pluto. Unlike asteroids, KBOs have not been heated by the sun and are thought to represent a pristine, well preserved deep-freeze sample of what the outer solar system was like following its birth 4.6 billion years ago. The KBOs found in the Hubble data are thought to be the building blocks of dwarf planets such as Pluto. Read more: 1.usa.gov/1vzUcyK NASA image use policy. NASA Goddard Space Flight Center enables NASA’s mission through four scientific endeavors: Earth Science, Heliophysics, Solar System Exploration, and Astrophysics. Goddard plays a leading role in NASA’s accomplishments by contributing compelling scientific knowledge to advance the Agency’s mission. Follow us on Twitter Like us on Facebook Find us on Instagram

The Density of Mid-sized Kuiper Belt Objects from ALMA Thermal Observations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brown, Michael E.; Butler, Bryan J.

The densities of mid-sized Kuiper Belt objects (KBOs) are a key constraint in understanding the assembly of objects in the outer solar system. These objects are critical for understanding the currently unexplained transition from the smallest KBOs with densities lower than that of water, to the largest objects with significant rock content. Mapping this transition is made difficult by the uncertainties in the diameters of these objects, which maps into an even larger uncertainty in volume and thus density. The substantial collecting area of the Atacama Large Millimeter Array allows significantly more precise measurements of thermal emission from outer solarmore » system objects and could potentially greatly improve the density measurements. Here we use new thermal observations of four objects with satellites to explore the improvements possible with millimeter data. We find that effects due to effective emissivity at millimeter wavelengths make it difficult to use the millimeter data directly to find diameters and thus volumes for these bodies. In addition, we find that when including the effects of model uncertainty, the true uncertainties on the sizes of outer solar system objects measured with radiometry are likely larger than those previously published. Substantial improvement in object sizes will likely require precise occultation measurements.« less

OSS: OSSOS Survey Simulator

NASA Astrophysics Data System (ADS)

Petit, J.-M.; Kavelaars, J. J.; Gladman, B.; Alexandersen, M.

2018-05-01

Comparing properties of discovered trans-Neptunian Objects (TNOs) with dynamical models is impossible due to the observational biases that exist in surveys. The OSSOS Survey Simulator takes an intrinsic orbital model (from, for example, the output of a dynamical Kuiper belt emplacement simulation) and applies the survey biases, so the biased simulated objects can be directly compared with real discoveries.

Why we need detailed visible-range spectral data on Kuiper belt objects?

NASA Astrophysics Data System (ADS)

Busarev, V. V.

2001-05-01

Our understanding of Kuiper belt objects (KBOs)' nature may be based on two general scenarios of their origin. First, they could result from early accretional phases of the Solar System ``in situ". Then they are probably the most primitive and unprocessed bodies among known and should be mostly icy, with a very low content of silicate component. Second, a considerable portion of them (if not a majority) might have been thrown by Jupiter and other giant planets from their zones of accumulation. If so, they could include much more silicates (possibly up to 40%). To check the suppositions we need high-resolution visible and near-infrared spectral data on Centaurs (as possible `fugitives' from the Kuiper belt) and the KBOs. Because of faintness of the objects their physicochemical properties remain still little-known. Visible-range observations of the bodies by means of a spacecraft approaching to the belt could much help in solving the problem. Visible-infrared spectrophotometric observations of the objects showed a considerable diversity among them (Jewitt D. & J. Luu, 1998, Astron. J., 115, 1667-1670). It hints at a diversity in content of their matter. Spectral features of ices could not probably dominate in the visible range spectra of silicate-bearing KBOs. Reflectance spectra of principal gases' frosts are mainly flat and featureless in the range (Wagner J. K. et al., 1987, Icarus, 69, 14-28). Besides, silicates of KBOs are probably oxidized and hydrated to a high extent. Highly hydrated main-belt C-class asteroids have absorption bands at 0.43 and 0.6-0.8 microns (up to about 5%) (Vilas F. & M. J. Gaffey, 1989, Science, 246, 790-792 and Vilas F. et al., 1993, Icarus, 102, 225-231). Similar spectral features attributed to oxidized and hydrated silicates were also found on many M- and S-asteroids (e. g., Busarev V. V., 2001, LPSC XXXII, abstract 1927). The absorption bands are interpreted as caused by electronic processes in a bulk of oxidized silicates and hydrated clay minerals including structural OH-groups. Thus, the absorption features may be considered as indicators of a presence of oxidized and/or hydrated silicates on a solid body regardless of its position in the Solar System. For these reasons we have started visible-range spectroscopic observations of Centaurs and the KBOs on Russian 6-m telescope.

Growth of asteroids, planetary embryos, and Kuiper belt objects by chondrule accretion

PubMed Central

Johansen, Anders; Low, Mordecai-Mark Mac; Lacerda, Pedro; Bizzarro, Martin

2015-01-01

Chondrules are millimeter-sized spherules that dominate primitive meteorites (chondrites) originating from the asteroid belt. The incorporation of chondrules into asteroidal bodies must be an important step in planet formation, but the mechanism is not understood. We show that the main growth of asteroids can result from gas drag–assisted accretion of chondrules. The largest planetesimals of a population with a characteristic radius of 100 km undergo runaway accretion of chondrules within ~3 My, forming planetary embryos up to Mars’s size along with smaller asteroids whose size distribution matches that of main belt asteroids. The aerodynamical accretion leads to size sorting of chondrules consistent with chondrites. Accretion of millimeter-sized chondrules and ice particles drives the growth of planetesimals beyond the ice line as well, but the growth time increases above the disc lifetime outside of 25 AU. The contribution of direct planetesimal accretion to the growth of both asteroids and Kuiper belt objects is minor. In contrast, planetesimal accretion and chondrule accretion play more equal roles in the formation of Moon-sized embryos in the terrestrial planet formation region. These embryos are isolated from each other and accrete planetesimals only at a low rate. However, the continued accretion of chondrules destabilizes the oligarchic configuration and leads to the formation of Mars-sized embryos and terrestrial planets by a combination of direct chondrule accretion and giant impacts. PMID:26601169

Growth of asteroids, planetary embryos, and Kuiper belt objects by chondrule accretion

NASA Astrophysics Data System (ADS)

Johansen, Anders; Mac Low, Mordecai-Mark; Lacerda, Pedro; Bizzarro, Martin

2015-04-01

Chondrules are millimeter-sized spherules that dominate primitive meteorites (chondrites) originating from the asteroid belt. The incorporation of chondrules into asteroidal bodies must be an important step in planet formation, but the mechanism is not understood. We show that the main growth of asteroids can result from gas drag-assisted accretion of chondrules. The largest planetesimals of a population with a characteristic radius of 100 km undergo runaway accretion of chondrules within ~3 My, forming planetary embryos up to Mars's size along with smaller asteroids whose size distribution matches that of main belt asteroids. The aerodynamical accretion leads to size sorting of chondrules consistent with chondrites. Accretion of millimeter-sized chondrules and ice particles drives the growth of planetesimals beyond the ice line as well, but the growth time increases above the disc lifetime outside of 25 AU. The contribution of direct planetesimal accretion to the growth of both asteroids and Kuiper belt objects is minor. In contrast, planetesimal accretion and chondrule accretion play more equal roles in the formation of Moon-sized embryos in the terrestrial planet formation region. These embryos are isolated from each other and accrete planetesimals only at a low rate. However, the continued accretion of chondrules destabilizes the oligarchic configuration and leads to the formation of Mars-sized embryos and terrestrial planets by a combination of direct chondrule accretion and giant impacts.

Growth of asteroids, planetary embryos, and Kuiper belt objects by chondrule accretion.

PubMed

Johansen, Anders; Low, Mordecai-Mark Mac; Lacerda, Pedro; Bizzarro, Martin

2015-04-01

Chondrules are millimeter-sized spherules that dominate primitive meteorites (chondrites) originating from the asteroid belt. The incorporation of chondrules into asteroidal bodies must be an important step in planet formation, but the mechanism is not understood. We show that the main growth of asteroids can result from gas drag-assisted accretion of chondrules. The largest planetesimals of a population with a characteristic radius of 100 km undergo runaway accretion of chondrules within ~3 My, forming planetary embryos up to Mars's size along with smaller asteroids whose size distribution matches that of main belt asteroids. The aerodynamical accretion leads to size sorting of chondrules consistent with chondrites. Accretion of millimeter-sized chondrules and ice particles drives the growth of planetesimals beyond the ice line as well, but the growth time increases above the disc lifetime outside of 25 AU. The contribution of direct planetesimal accretion to the growth of both asteroids and Kuiper belt objects is minor. In contrast, planetesimal accretion and chondrule accretion play more equal roles in the formation of Moon-sized embryos in the terrestrial planet formation region. These embryos are isolated from each other and accrete planetesimals only at a low rate. However, the continued accretion of chondrules destabilizes the oligarchic configuration and leads to the formation of Mars-sized embryos and terrestrial planets by a combination of direct chondrule accretion and giant impacts.

Detection Technique for Artificially Illuminated Objects in the Outer Solar System and Beyond

PubMed Central

Loeb, Abraham

2012-01-01

Abstract Existing and planned optical telescopes and surveys can detect artificially illuminated objects, comparable in total brightness to a major terrestrial city, at the outskirts of the Solar System. Orbital parameters of Kuiper belt objects (KBOs) are routinely measured to exquisite precisions of<10−3. Here, we propose to measure the variation of the observed flux F from such objects as a function of their changing orbital distances D. Sunlight-illuminated objects will show a logarithmic slope α ≡ (d log F/d log D)=−4, whereas artificially illuminated objects should exhibit α=−2. The proposed Large Synoptic Survey Telescope (LSST) and other planned surveys will provide superb data and allow measurement of α for thousands of KBOs. If objects with α=−2 are found, follow-up observations could measure their spectra to determine whether they are illuminated by artificial lighting. The search can be extended beyond the Solar System with future generations of telescopes on the ground and in space that would have the capacity to detect phase modulation due to very strong artificial illumination on the nightside of planets as they orbit their parent stars. Key Words: Astrobiology—SETI—Kuiper belt objects—Artificial illumination. Astrobiology 12, 290–294. PMID:22490065

Kenneth Essex Edgeworth—Victorian polymath and founder of the Kuiper belt?

NASA Astrophysics Data System (ADS)

McFarland, John

This article is a biographical note on Kenneth Essex Edgeworth (1880-1972), Army officer, engineer, economist and independent theoretical astronomer. Abibliography of Edgeworth's known papers is incorporated, and his interesting cosmogonic theories are highlighted, in particular his postulation in 1943 of a source of potential comets occupying the region of the solar system beyond Neptune, recently termed the Kuiper belt.

Studies of Disks Around the Sun and Other Stars

NASA Technical Reports Server (NTRS)

Stern, S. Alan

1997-01-01

This is a NASA Origins of Solar Systems research program, and this NASA Headquarters grant has now been transferred to a new grant at NASA GSFC (NAG5-4082). Thus the need for this 'Final Report' on a project that is not, in fact, complete. We are conducting research designed to enhance our understanding of the evolution and detectability of comet clouds and disks. This area holds promise for also improving our understanding of outer solar system formation, the bombardment history of the planets, the transport of volatiles and organics from the outer solar system to the inner planets, and to the ultimate fate of comet clouds around the Sun and other stars. According to "standard" theory, both the Kuiper Belt and the Oort Cloud are (at least in part) natural products of the planetary accumulation stage of solar system formation. One expects such assemblages to be a common attribute of other solar systems. Our program consists of modeling collisions in the Kuiper Belt and the dust disks around other stars. The modeling effort focuses on moving from our simple, first-generation, Kuiper Belt collision rate model, to a time-dependent, second-generation model that incorporates physical collisions, velocity evolution, dynamical erosion, and various dust transport mechanisms. This second generation model is to be used to study the evolution of surface mass density and the object-size spectrum in the disk.

Time-Resolved Near-Infrared Photometry of Extreme Kuiper Belt Object Haumea

NASA Astrophysics Data System (ADS)

Lacerda, Pedro

2009-02-01

We present time-resolved near-infrared (J and H) photometry of the extreme Kuiper belt object (136108) Haumea (formerly 2003 EL61) taken to further investigate rotational variability of this object. The new data show that the near-infrared peak-to-peak photometric range is similar to the value at visible wavelengths, ΔmR = 0.30 ± 0.02 mag. Detailed analysis of the new and previous data reveals subtle visible/near-infrared color variations across the surface of Haumea. The color variations are spatially correlated with a previously identified surface region, redder in B - R and darker than the mean surface. Our photometry indicates that the J - H colors of Haumea (J - H = -0.057 ± 0.016 mag) and its brightest satellite Hi'iaka (J - H = -0.399 ± 0.034 mag) are significantly (greater than 9σ) different. The satellite Hi'iaka is unusually blue in J - H, consistent with strong 1.5 μm water-ice absorption. The phase coefficient of Haumea is found to increase monotonically with wavelength in the range 0.4 < λ < 1.3. We compare our findings with other solar system objects and discuss implications regarding the surface of Haumea.

Origin of Outer Solar System

NASA Technical Reports Server (NTRS)

Holman, Matthew J.; Lindstrom, David (Technical Monitor)

2005-01-01

Our ongoing research program combines extensive deep and wide-field observations using a variety of observational platforms with numerical studies of the dynamics of small bodies in the outer solar system in order to advance the main scientific goals of the community studying the Kuiper belt and the outer solar system. These include: (1) determining the relative populations of the known classes of KBOs as well as other possible classes; ( 2 ) determining the size distributions or luminosity function of the individual populations or the Kuiper belt as a whole; (3) determining the inclinations distributions of these populations; (4) establishing the radial extent of the Kuiper belt; ( 5 ) measuring and relating the physical properties of different types of KBOs to those of other solar system bodies; and, (6) completing our systematic inventory of the satellites of the outer planets.

Structure and Evolution of Kuiper Belt Objects: The Case for Compositional Classes

NASA Astrophysics Data System (ADS)

McKinnon, William B.; Prialnik, D.; Stern, S. A.

2007-10-01

Kuiper belt objects (KBOs) accreted from a mélange of ices, carbonaceous matter, and rock of mixed interstellar and solar nebular provenance. The transneptunian region, where this accretion took place, was likely more radially compact than today. This and the influence of gas drag during the solar nebula epoch argue for more rapid KBO accretion than usually considered. Early evolution of KBOs was largely the result of radiogenic heating, with both short-term and long-term contributions being potentially important. Depending on rock content and porous conductivity, KBO interiors may have reached relatively high temperatures. Models suggest that KBOs likely lost very volatile ices during early evolution, whereas less volatile ices should be retained in cold, less altered subsurface layers; initially amorphous ice may have crystallized in the interior as well, releasing trapped volatiles. Generally, KBOs should be stratified in terms of composition and porosity, albeit subject to impact disruption and collisional stripping. KBOs are thus unlikely to be "the most pristine objects in the Solar System.” Large (dwarf planet) KBOs may be fully differentiated. KBO surface color and compositional classes are usually discussed in terms of "nature vs. nurture,” i.e., a generic primordial composition vs. surface processing, but the true nature of KBOs also depends on how they have evolved. The broad range of albedos now found in the Kuiper belt, deep water-ice absorptions on some objects, evidence for differentiation of Pluto and 2003 EL61, and a range of densities incompatible with a single, primordial composition and variable porosity strongly imply significant, intrinsic compositional differences among KBOs. The interplay of formation zone (accretion rate), body size, and dynamical (collisional) history may yield KBO compositional classes (and their spectral correlates) that recall the different classes of asteroids in the inner Solar System, but whose members are broadly distributed among the KBO dynamical subpopulations.

Two Color Populations of Kuiper Belt and Centaur Objects and the Smaller Orbital Inclinations of Red Centaur Objects

NASA Astrophysics Data System (ADS)

Tegler, S. C.; Romanishin, W.; Consolmagno, G. J.; J., S.

2016-12-01

We present new optical colors for 28 Kuiper Belt objects (KBOs) and 35 Centaur objects measured with the 1.8 m Vatican Advanced Technology Telescope and the 4.3 m Discovery Channel Telescope. By combining these new colors with our previously published colors, we increase the sample size of our survey to 154 objects. Our survey is unique in that the uncertainties in our color measurements are less than half the uncertainties in the color measurements reported by other researchers in the literature. Small uncertainties are essential for discerning between a unimodal and a bimodal distribution of colors for these objects as well as detecting correlations between colors and orbital elements. From our survey, it appears red Centaurs have a broader color distribution than gray Centaurs. We find red Centaurs have a smaller orbital inclination angle distribution than gray Centaurs at the 99.3% confidence level. Furthermore, we find that our entire sample of KBOs and Centaurs exhibits bimodal colors at the 99.4 % confidence level. KBOs and Centaurs with H V > 7.0 have bimodal colors at the 99.96% confidence level and KBOs with H V < 6.0 have bimodal colors at the 96% confidence level.

Small Bodies in the Kuiper Belt : Lessons from Pluto's Small Satellites

NASA Astrophysics Data System (ADS)

Weaver, H. A., Jr.; Buie, M. W.; Howett, C.; Olkin, C.; Parker, A. H.; Parker, J. W.; Porter, S. B.; Robbins, S. J.; Singer, K. N.; Spencer, J. R.; Stern, A.; Young, L. A.; Zangari, A. M.; Lauer, T.; Showalter, M.; Verbiscer, A.; McKinnon, W. B.; Cook, J. C.; Grundy, W. M.; Protopapa, S.; Hamilton, D. P.; Schmitt, B.; Buratti, B. J.; Binzel, R. P.; Jennings, D. E.; Reuter, D.; Cruikshank, D. P.; Dalle Ore, C.; Ennico Smith, K.; Moore, J. M.; Cheng, A. F.; Lisse, C. M.

2017-12-01

During the approach and flyby of the Pluto system in 2015, the instruments on theNew Horizons spacecraft obtained data on Pluto's small satellites that far surpassedwhat was previously available. All four small moons (Styx, Nix, Kerberos, and Hydra,in order of distance from Pluto) have highly irregular shapes, rapid non-synchronous rotation rates, high obliquity rotational poles, high visible albedos ( 50-80%), andneutral-to-blue visible colors. The even more detailed information obtained for Nix and Hydra reveal those 40 km diameter objects to have relatively ancient ( 3-4 Gyr) surfacesdominated by crystalline water ice, but with a hint of ammonia-containing compounds. Here we addresswhat these results say about the origin and evolution of these bodies, and howthese results inform studies of other small bodies in the Kuiper belt, including2014 MU69, the next flyby target for the New Horizons mission.

A Laboratory Impact Study of Simulated Edgeworth-Kuiper Belt Objects

NASA Astrophysics Data System (ADS)

Ryan, Eileen V.; Davis, Donald R.; Giblin, Ian

1999-11-01

This paper reports on a series of laboratory impact experiments designed to provide basic data on how simulated Edgeworth-Kuiper belt objects (EKOs) fragment in an impact event. In September-October 1997 we carried out 20 low-velocity airgun shots at the Ames Vertical Gun Range into porous and homogeneous ice spheres using aluminum, fractured ice, and solid ice projectiles. We found that the porous ice targets behaved as strongly as solid ice in collision. Energy is apparently well dissipated by the void spaces within the target, such that these fragile ice structures respond as if they were strong in impacts. Therefore, it would appear that if EKOs are porous, they are not collisionally weak. Also, our data show that collisional outcomes for low-velocity impacts into ice targets depend on the type of projectile used as well as the properties of the target. We observed that the degree of fragmentation for a given type of target increases as the strength of the projectile increases. Aluminum projectiles are far more damaging to the target at the same collisional energy than are solid ice projectiles, which, in turn, are more damaging than fractured ice projectiles. One possible explanation for this behavior is the variable depth of penetration of the projectile for the different cases—stronger projectiles penetrate more deeply and couple more energy into the target than do weak projectiles. Based on this, if we assume that there has not been significant heating or differentiation in the Edgeworth-Kuiper (E-K) belt, the most applicable impact strength for the low-velocity E-K belt collisions is likely to be that derived from similar target/projectile materials impacting each other. The laboratory data from this analysis indicate that a value for impact strength>5×10 5 erg/cm 3 is appropriate for porous ice targets impacted with solid/porous ice projectiles.

Three-body affairs in the outer solar system

NASA Astrophysics Data System (ADS)

Funato, Yoko; Makino, Junichiro; Hut, Piet; Kokubo, Eiichiro; Kinoshita, Daisuke

Recent observations have revealed an unexpectedly high binary fraction among the Trans-Neptunian Objects (TNOs) that populate the Kuiper Belt. The TNO binaries are strikingly different from asteroid binaries in four respects: their frequency is an order of magnitude larger, the mass ratio of their components is closer to unity, and their orbits are wider and highly eccentric. Two explanations have been proposed for their formation, one assuming large numbers of massive bodies, and one assuming large numbers of light bodies. We argue that both assumptions are unwarranted, and we show how TNO binaries can be produced from a modest number of intermediate-mass bodies of the type predicted by the gravitational instability theory for the formation of planetesimals. We start with a TNO binary population similar to the asteroid binary population, but subsequently modified by three-body exchange reactions, a process that is far more efficient in the Kuiper belt, because of the much smaller tidal perturbations by the Sun. Our mechanism can naturally account for all four characteristics that distinguish TNO binaries from main-belt asteroid binaries.

Surface Compositions Across Pluto and Charon

NASA Technical Reports Server (NTRS)

Grundy, W. M.; Binzel, R. P.; Buratti, B. J.; Cook, J. C.; Cruikshank, D. P.; Dalle Ore, C. M.; Earle, A. M.; Ennico, K.; Howett, C. J. A.; Lunsford, A. W.;

Former 9th and possible future 9th planet in the Solar system

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.

2016-12-01

4 terrestrial planets and 4 giant planets were formed in the Solar system. The Main asteroid belt is located between them, and the Kuiper belt and Oort cloud are located beyond the giant planets. Therefore, the planetary system is surrounded by a swarm of rocky-icy bodies up to a distance of 105 AU. The former 9th planet in the Solar system, Pluto, is the first known object of the Kuiper Belt. Due to data from the spacecraft "New Horizons" we made significant progress in the study of the physical characteristics of the object and its surface. Numerous observations have shown that the Kuiper belt itself is dynamically stable. And the source of cometary nuclei is a disk scattered by the gravitational perturbation of the giant planets more than 4 billion years ago. Recently, it was reported on indirect evidence of the existence of a new 9th planet in the Solar system with a mass 10 times greater than the mass of the Earth, a distance from the Sun ∼200 AU at perihelion, 600-1200 AU at aphelion, and an orbital period of ∼15000 years. These conclusions are based on the calculation of the orbits of 6 presently known objects of the scattered disc. We pay attention that, in moments close to their discovery, they were located near the perihelion, had a maximum brightness and a maximum orbital velocity. On the basis of probabilistic assumptions, we estimated that the probable number of the same bodies with eccentric orbits should be estimated at many thousands rather than at a few. For the initial evaluation, we used observational data from the Infrared Space Telescope "WISE". They showed that any Saturn's analog has not been registered at distances up to 30 000 AU. Therefore, a super-Earth with a radius of <11000 km (with a mass of ∼10 Earth masses) would have been seen at a distance up to 1000 AU. Thus, either unknown 9th planet is now at a greater distance, or these results cannot be directly scaled to the super-Earth with a disproporti! onately lower internal heat reserves.

Pluto or Bust!

ERIC Educational Resources Information Center

Fisher, Diane

2005-01-01

This article begins with a discussion of the development of the solar system. It also focuses on the fact that in January 2006, NASA plans to launch the New Horizons spacecraft to Pluto-Charon and on to one or more of the icy Kuiper Belt Objects. Sections of the article include: (1) Investigating the Aftermath; (2) Designing a Mission to…

Solar System Observations with Spitzer Space Telescope: Preliminary Results

NASA Technical Reports Server (NTRS)

Cruikshank, Dale P.

2005-01-01

The programs of observations of Solar System bodies conducted in the first year of the operation of the Spitzer Space Telescope as part of the Guaranteed Observing Time allocations are described. Initial results include the determination of the albedos of a number of Kuiper Belt objects and Centaurs from observations of their flux densities at 24 and 70 microns, and the detection of emission bands in the spectra of several distant asteroids (Trojans) around 10 and 25 microns. The 10 Kuiper Belt objects observed to date have albedos in the range 0.08 - 0.15, significantly higher than the earlier estimated 0.04. An additional KBO [(55565) 2002 AW(sub l97)] has an albedo of 0.17 plus or minus 0.03. The emission bands in the asteroid spectra are indicative of silicates, but specific minerals have not yet been identified. The Centaur/comet 29P/Schwassmann-Wachmann 1 has a nucleus surface albedo of 0.025 plus or minus 0.01, and its dust production rate was calculated from the properties of the coma. Several other investigations are in progress as the incoming data are processed and analyzed.

The La Silla-QUEST Kuiper Belt Survey

NASA Astrophysics Data System (ADS)

Rabinowitz, David; Schwamb, Megan E.; Hadjiyska, Elena; Tourtellotte, Suzanne

2012-11-01

We describe the instrumentation and detection software and characterize the detection efficiency of an automated, all-sky, southern-hemisphere search for Kuiper Belt Objects (KBOs) brighter than R mag 21.4. The search relies on Yale University's 160 Megapixel QUEST camera, previously used for the successful surveys at Palomar that detected most of the distant dwarf planets, and now installed on the ESO 1.0 m Schmidt telescope at La Silla, Chile. Extensive upgrades were made to the telescope control system to support automation, and significant improvements were made to the camera. To date, 63 new KBOs have been discovered, including a new member of the Haumea collision family (2009 YE7) and a new distant object with an inclination exceeding 70° (2010 WG9). In a survey covering ~7500 deg2, we have thus far detected 77 KBOs and Centaurs, more than any other full-hemisphere search to date. Using a pattern of dithered pointings, we demonstrate a search efficiency exceeding 80%. We are currently on track to complete the southern-sky survey and detect any bright KBOs that have eluded detection from the north.

Tracking an Exodus: Lost Children of the Dwarf Planet Haumea

NASA Astrophysics Data System (ADS)

Maggard, Steven; Ragozzine, Darin

2017-10-01

The orbital properties of Kuiper Belt Objects (KBOs) refine our understanding of the formation of the solar system. One object of particular interest is the dwarf planet Haumea which experienced a collision in the early stages of our solar system that ejected shards form its surface and spread them over a localized part of the Kuiper Belt. Detailed orbital integrations are required to determine the dynamical distances between family members, in the form of "Delta v" as measured from conserved proper orbital elements (Ragozzine & Brown 2007). In the past 10 years, the number of known KBOs has tripled; here, we perform dynamical integrations to triple the number of candidate Haumea family members. The resulting improved understanding of Haumea's family will bring us closer to understanding its formation. In order to place more secure estimates on the dynamical classification of Haumea family members (and KBOs generally), we use OpenOrb to perform rigorous Bayesian uncertainty propagation from observational uncertainty into orbital elements and then into dynamical classifications. We will discuss our methodology, the new Haumea family members, and some implications for the Haumea family.

Analysis of Potential Radical Chemistry on Kuiper Belt Objects

NASA Astrophysics Data System (ADS)

Yanez, Maya Danielle; Hodyss, Robert; Cable, Morgan; Johnson, Paul

2017-10-01

Kuiper Belt Objects (KBOs) are of high interest following the New Horizons encounter with the Pluto system and the extended mission to 2014MU69. We aimed to clarify questions raised concerning the possible presence of organic radicals formed from photolysis on the surface of KBOs and other Trans-Neptunian Objects, and obtain laboratory spectra of these radicals for comparison to remote sensing data. We explored the photochemical generation of methyl radical from matrix-isolated CH3I in an attempt to create sufficient amounts of the methyl radical to obtain spectra in the near infrared. Both Ar and N2 matrices were studied, as well as varying guest:matrix ratios. Hydrogen lamp irradiation was found to be more effective than mercury lamp irradiation. The irradiation time was a significant factor when we switched matrices: methyl radical depleted rapidly in the N2 matrix with prolonged irradiation (~10 hours) whereas it survived for over 48 hours in some experiments with the Ar matrix. Reaction of the methyl radical with the N2 matrix to form HCN was observed. Future experiments will focus on alternate methods of radical generation in order to increase the yield of trapped radical.

ALMA 1.3 mm Map of the HD 95086 System

NASA Astrophysics Data System (ADS)

Su, Kate Y. L.; MacGregor, Meredith A.; Booth, Mark; Wilner, David J.; Flaherty, Kevin; Hughes, A. Meredith; Phillips, Neil M.; Malhotra, Renu; Hales, Antonio S.; Morrison, Sarah; Ertel, Steve; Matthews, Brenda C.; Dent, William R. F.; Casassus, Simon

2017-12-01

Planets and minor bodies such as asteroids, Kuiper-Belt objects, and comets are integral components of a planetary system. Interactions among them leave clues about the formation process of a planetary system. The signature of such interactions is most prominent through observations of its debris disk at millimeter wavelengths where emission is dominated by the population of large grains that stay close to their parent bodies. Here we present ALMA 1.3 mm observations of HD 95086, a young early-type star that hosts a directly imaged giant planet b and a massive debris disk with both asteroid- and Kuiper-Belt analogs. The location of the Kuiper-Belt analog is resolved for the first time. The system can be depicted as a broad (ΔR/R ˜ 0.84), inclined (30° ± 3°) ring with millimeter emission peaked at 200 ± 6 au from the star. The 1.3 mm disk emission is consistent with a broad disk with sharp boundaries from 106 ± 6 to 320 ± 20 au with a surface density distribution described by a power law with an index of -0.5 ± 0.2. Our deep ALMA map also reveals a bright source located near the edge of the ring, whose brightness at 1.3 mm and potential spectral energy distribution are consistent with it being a luminous star-forming galaxy at high redshift. We set constraints on the orbital properties of planet b assuming coplanarity with the observed disk.

IRAC Monitoring of the Late Heavy Comet Bombardment in the eta Corvi System

NASA Astrophysics Data System (ADS)

Marengo, Massimo; Lisse, Carey; Stapelfeldt, Karl; Hulsebus, Alan

2014-12-01

The nearby sun-like star eta Corvi (F2V, d=18 pc, age =1.2 Gyr) has long been known to possess a bright, dusty Kuiper Belt that has now been resolved with Herschel PACS. A warm inner dust belt indicated by an IRAS 12 micron excess and has recently been resolved as a 3-AU scale structure by VLT observations. In 2012 Lisse et al. further characterized this warm dust using Spitzer IRS, identifying the signatures of ice, organics and silicate dust in this system's Terrestrial Habitability Zone (THZ). The system appears to be undergoing a Late Heavy Bombardment (LHB), delivering primitive, water- and organic-rich material from the Kuiper Belt to the THZ, at roughly the same relative age as the solar system's LHB. Our data also showed an upturn in the excess flux shortwards of 6 micron ? evidence for a surprisingly large amount of icy dust scattering in the inner system (fscat/fstar ~ 1.0%). This results is corroborated by our recent 2-5 micron NASA/IRTF SpeX spectroscopy. In 2012 we have obtained Spitzer/IRAC photometric data for the system, detecting the disk at 3.6 and 4.5 micron in two separate epochs, followed by a third epoch in 2013. We now propose to continue our photometric monitoring with 15 additional visits to be scheduled within cycle 11, in order to extend our temporal coverage to 4 years on a variety of timescales ranging from days, to weeks, to months. The proposed campaign will allow us to test the two competing hypothesis for the origin of the warm disk: (1) single collison event leading to the breakup of a large Kuiper Belt object in the system or (2) continual raining of small comets scattered towards the inner system.

Structure and Evolution of Kuiper Belt Objects and Dwarf Planets

NASA Astrophysics Data System (ADS)

McKinnon, W. B.; Prialnik, D.; Stern, S. A.; Coradini, A.

Kuiper belt objects (KBOs) accreted from a mélange of volatile ices, carbonaceous matter, and rock of mixed interstellar and solar nebular provenance. The transneptunian region, where this accretion took place, was likely more radially compact than today. This and the influence of gas drag during the solar nebula epoch argue for more rapid KBO accretion than usually considered. Early evolution of KBOs was largely the result of heating due to radioactive decay, the most important potential source being 26Al, whereas long-term evolution of large bodies is controlled by the decay of U, Th, and 40K. Several studies are reviewed dealing with the evolution of KBO models, calculated by means of one-dimensional numerical codes that solve the heat and mass balance equations. It is shown that, depending on parameters (principally rock content and porous conductivity), KBO interiors may have reached relatively high temperatures. The models suggest that KBOs likely lost ices of very volatile species during early evolution, whereas ices of less-volatile species should be retained in cold, less-altered subsurface layers. Initially amorphous ice may have crystallized in KBO interiors, releasing volatiles trapped in the amorphous ice, and some objects may have lost part of these volatiles as well. Generally, the outer layers are far less affected by internal evolution than the inner part, which in the absence of other effects (such as collisions) predicts a stratified composition and altered porosity distribution. Kuiper belt objects are thus unlikely to be "the most pristine objects in the solar system," but they do contain key information as to how the early solar system accreted and dynamically evolved. For large (dwarf planet) KBOs, long-term radiogenic heating alone may lead to differentiated structures -- rock cores, ice mantles, volatile-ice-rich "crusts," and even oceans. Persistence of oceans and (potential) volcanism to the present day depends strongly on body size and the melting-point depression afforded by the presence of salts, ammonia, etc. (we review the case for Charon in particular). The surface color and compositional classes of KBOs are usually discussed in terms of "nature vs. nurture," i.e., a generic primordial composition vs. surface processing, but the true nature of KBOs also depends on how they have evolved. The broad range of albedos now found in the Kuiper belt, deep water-ice absorptions on some objects, evidence for differentiation of Pluto and 2003 EL61, and a range of densities incompatible with a single, primordial composition and variable porosity strongly imply significant, intrinsic compositional differences among KBOs. The interplay of formation zone (accretion rate), body size, and dynamical (collisional) history may yield KBO compositional classes (and their spectral correlates) that recall the different classes of asteroids in the inner solar system, but whose members are broadly distributed among the KBO dynamical subpopulations.

Space Education at the University of Texas at San Antonio: Army Space Cadre - Learn from Southwest Research Institute Scientists (Army Space Journal, 2009 Summer Edition)

DTIC Science & Technology

2009-01-01

Neptune and is similar to the asteroid belt , although it is far larger. Cassini studies the planet Saturn and its moons. The space- craft consists of two...and the Kuiper belt , beginning in 2015. The New Horizons spacecraft executed a fly-by of Jupiter in 2007. The Jupiter fly- by was used to provide a...gravitational assist that shaved years off the travel time to Pluto-Charon and the Kuiper belt . Charon is the largest moon of the dwarf planet

Organic Solid Matter as a Coloring Agent in Outer Solar System Bodies

NASA Technical Reports Server (NTRS)

Cruikshank, D. P.; DalleOre, C. M.; Roush, T. L.; Khare, B. N.; Fonda, Mark (Technical Monitor)

2002-01-01

Small bodies in the outer Solar System OSS, exhibit a range of color, or slope of the reflectance in the photovisual spectral region, ranging from neutral to very red, sometimes with and sometimes without distinct absorption bands. These objects range in geometric albedo from 0.03 to 1.0, with the higher albedo objects typically showing clear evidence of water ice. Water ice has also been found in a few objects with albedo 0. 1 or less. We explore here the identification of the material or materials that color these icy and non-icy surfaces through scattering models that incorporate minerals, meteoritic material, and organic solids (tholins) produced ID the laboratory by energy deposition in ices and gases. These models must match not only the color in the photovisual region, but the spectral reflectance properties throughout the near-infrared. Among some classes of objects, such as Kuiper Belt objects, the coloring agent may be a single material that is present in greater or lesser abundance, thus accounting for the range in color from neutral to very red. This may also apply to the Centaur objects, the Jovian Trojans, and the outer-main belt asteroids, each taken as a separate class. If so, each class may be colored to varying degrees by a different material, or they all might be colored by a common material that is widespread throughout the OSS, from 3 to 50 AU, and beyond. In this paper, we model the reflectances of "Kuiper Belt objects, Centaurs, Trojans, outer ARAB asteroids, and planetary satellites. Our models show that the reddest surfaces cannot be colored by minerals or meteoritic materials, but can be matched throughout the photovisual and near-infrared by organic solids, specifically certain tholins.

Kuiper Belt Objects of different sizes and average densities: thermal evolution scenarios and modern structure of matter

NASA Astrophysics Data System (ADS)

Shchuko, O. B.; Shchuko, S. D.; Kartashov, D.; Orosei, R.

2012-04-01

Thermal evolution of accretion-formed Kuiper Belt Objects (KBOs) with modern sizes from 200 to 2000 km and average densities from 1100 to 3200 kg/m3 has been studied by mathematical simulation methods. The values range of physical parameters of the accretion material and ultimate radionuclide content, securing KBO existence at present, have been found. The solid dust material of protosolar cloud fringe regions and fine-fractured H2O condensate in the form of amorphous ice are considered to have been the building matter for these objects. This material was represented by small dust particles of different chemical and mineralogical composition, embedded with radionuclides 238U, 235U, 232Th, 40K providing the sources of radiogenic heat. H2O condensate secured the presence of amorphous ice in the forming body's matter. Radiogenic heat leads to H2O phase transitions which define a body's interior matter differentiation. The radionuclide content at the initial time of the body formation determined the dynamically changing degree of the interior matter differentiation at different KBO depths for the whole period from the initial up to the present time. For the models of the celestial objects considered, the dynamically changing boundaries of spherically symmetric regions with different degree of matter differentiation have been determined.

Chiron and the Centaurs: Escapees from the Kuiper Belt

NASA Technical Reports Server (NTRS)

Stern, Alan; Campins, Humberto

1996-01-01

The outer Solar System has long appeared to be a largely empty place, inhabited only by the four giant planets, Pluto and a transient population of comets. In 1977 however, a faint and enigmatic object - 2060 Chiron - was discovered moving on a moderately inclined, strongly chaotic 51-year orbit which takes it from just inside Saturn's orbit out almost as far as that of Uranus. It was not initially clear from where Chiron originated. these objects become temporarily trapped on Centaur-like orbits Following Chiron's discovery, almost 15 years elapsed before other similar objects were discovered; five more have now been identified. Based on the detection statistics implied by these discoveries, it has become clear that these objects belong to a significant population of several hundred (or possibly several thousand) large icy bodies moving on relatively short-lived orbits between the giant planets. This new class of objects, known collectively as the Centaurs, are intermediate in diameter between typical comets (1-20 km) and small icy planets such as Pluto (approx. 2,300 km) and Triton (approx. 2,700 km). Although the Centaurs are interesting in their own right, they have taken on added significance following the recognition that they most probably originated in the ancient reservoir of comets and larger objects located beyond the orbit of Neptune known as the Kuiper belt.

Interstellar Explorer Observations of the Solar System's Debris Disks

NASA Astrophysics Data System (ADS)

Lisse, C. M.; McNutt, R. L., Jr.; Brandt, P. C.

2017-12-01

Planetesimal belts and debris disks full of dust are known as the "signposts of planet formation" in exosystems. The overall brightness of a disk provides information on the amount of sourcing planetesimal material, while asymmetries in the shape of the disk can be used to search for perturbing planets. The solar system is known to house two such belts, the Asteroid belt and the Kuiper Belt; and at least one debris cloud, the Zodiacal Cloud, sourced by planetisimal collisions and Kuiper Belt comet evaporative sublimation. However these are poorly understood in toto because we live inside of them. E.g., while we know of the two planetesimal belt systems, it is not clear how much, if any, dust is produced from the Kuiper belt since the near-Sun comet contributions dominate near-Earth space. Understanding how much dust is produced in the Kuiper belt would give us a much better idea of the total number of bodies in the belt, especially the smallest ones, and their dynamical collisional state. Even for the close in Zodiacal cloud, questions remain concerning its overall shape and orientation with respect to the ecliptic and invariable planes of the solar system - they aren't explainable from the perturbations caused by the known planets alone. In this paper we explore the possibilities of using an Interstellar Explorer telescope placed at 200 AU from the sun to observe the brightness, shape, and extent of the solar system's debris disk(s). We should be able to measure the entire extent of the inner, near-earth zodiacal cloud; whether it connects smoothly into an outer cloud, or if there is a second outer cloud sourced by the Kuiper belt and isolated by the outer planets, as predicted by Stark & Kuchner (2009, 2010) and Poppe et al. (2012, 2016; Figure 1). VISNIR imagery will inform about the dust cloud's density, while MIR cameras will provide thermal imaging photometry related to the cloud's dust particle size and composition. Observing at high phase angle by looking back towards the sun from 200 AU, we will be able to perform deep searches for the presence of rings and dust clouds around discrete sources, and thus we will be able to search for possible strong individual sources of the debris clouds - like the Haumea family collisional fragments, or the rings of the Centaur Chariklo, or dust emitted from spallation off the 6 known bodies of the Pluto system.

THE CANADA-FRANCE ECLIPTIC PLANE SURVEY-FULL DATA RELEASE: THE ORBITAL STRUCTURE OF THE KUIPER BELT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petit, J.-M.; Rousselot, P.; Mousis, O.

2011-10-15

We report the orbital distribution of the trans-Neptunian objects (TNOs) discovered during the Canada-France Ecliptic Plane Survey (CFEPS), whose discovery phase ran from early 2003 until early 2007. The follow-up observations started just after the first discoveries and extended until late 2009. We obtained characterized observations of 321 deg{sup 2} of sky to depths in the range g {approx} 23.5-24.4 AB mag. We provide a database of 169 TNOs with high-precision dynamical classification and known discovery efficiency. Using this database, we find that the classical belt is a complex region with sub-structures that go beyond the usual splitting of innermore » (interior to 3:2 mean-motion resonance [MMR]), main (between 3:2 and 2:1 MMR), and outer (exterior to 2:1 MMR). The main classical belt (a = 40-47 AU) needs to be modeled with at least three components: the 'hot' component with a wide inclination distribution and two 'cold' components (stirred and kernel) with much narrower inclination distributions. The hot component must have a significantly shallower absolute magnitude (H{sub g} ) distribution than the other two components. With 95% confidence, there are 8000{sup +1800}{sub -1600} objects in the main belt with H{sub g} {<=} 8.0, of which 50% are from the hot component, 40% from the stirred component, and 10% from the kernel; the hot component's fraction drops rapidly with increasing H{sub g} . Because of this, the apparent population fractions depend on the depth and ecliptic latitude of a trans-Neptunian survey. The stirred and kernel components are limited to only a portion of the main belt, while we find that the hot component is consistent with a smooth extension throughout the inner, main, and outer regions of the classical belt; in fact, the inner and outer belts are consistent with containing only hot-component objects. The H{sub g} {<=} 8.0 TNO population estimates are 400 for the inner belt and 10,000 for the outer belt to within a factor of two (95% confidence). We show how the CFEPS Survey Simulator can be used to compare a cosmogonic model for the orbital element distribution to the real Kuiper Belt.« less

Circumstellar and circumplanetary disks

NASA Astrophysics Data System (ADS)

Chiang, Eugene

2000-11-01

This thesis studies disks in three astrophysical contexts: (1)protoplanetary disks; (2)the Edgeworth-Kuiper Belt; and (3)planetary rings. We derive hydrostatic, radiative equilibrium models of passive protoplanetary disks surrounding T Tauri and Herbig Ae/Be stars. Each disk is encased by an optically thin layer of superheated dust grains. This layer is responsible for up to ~70% of the disk luminosity at wavelengths between ~5 and 60 μm. The heated disk flares and absorbs more stellar radiation at a given stellocentric distance than a flat disk would. Spectral energy distributions are computed and found to compare favorably with the observed flattish infrared excesses of several young stellar objects. Spectral features from dust grains in the superheated layer appear in emission if the disk is viewed nearly face-on. We present the results of a pencil-beam survey of the Kuiper Belt using the Keck 10-m telescope. Two new objects are discovered. Data from all surveys are pooled to construct the luminosity function from mR = 20 to 27. The cumulative number of objects per square degree, Σ(< mR), is such that log10Σ (< mR) = 0.52(mR - 23.5). The luminosity function is consistent with a power-law size distribution for which the smallest objects possess most of the surface area but the largest bodies contain most of the mass. To order-of-magnitude, 0.2 M⊕ and 1 × 1010 comet progenitors lie between 30 and 50 AU. The classical Kuiper Belt appears truncated at a distance of 50 AU. We propose that rigid precession of narrow eccentric planetary rings surrounding Uranus and Saturn is maintained by a balance of forces due to ring self- gravity, planetary oblateness, and interparticle collisions. Collisional impulses play an especially dramatic role near ring edges. Pressure-induced accelerations are maximal near edges because there (1)velocity dispersions are enhanced by resonant satellite perturbations, and (2)the surface density declines steeply. Remarkably, collisional forces felt by material in the last ~100 m of a ~10 km wide ring can increase equilibrium masses up to a factor of ~100. New ring surface densities are derived which accord with Voyager radio measurements.

ON A POSSIBLE SIZE/COLOR RELATIONSHIP IN THE KUIPER BELT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pike, R. E.; Kavelaars, J. J., E-mail: repike@uvic.ca

2013-10-01

Color measurements and albedo distributions introduce non-intuitive observational biases in size-color relationships among Kuiper Belt Objects (KBOs) that cannot be disentangled without a well characterized sample population with systematic photometry. Peixinho et al. report that the form of the KBO color distribution varies with absolute magnitude, H. However, Tegler et al. find that KBO color distributions are a property of object classification. We construct synthetic models of observed KBO colors based on two B-R color distribution scenarios: color distribution dependent on H magnitude (H-Model) and color distribution based on object classification (Class-Model). These synthetic B-R color distributions were modified tomore » account for observational flux biases. We compare our synthetic B-R distributions to the observed ''Hot'' and ''Cold'' detected objects from the Canada-France Ecliptic Plane Survey and the Meudon Multicolor Survey. For both surveys, the Hot population color distribution rejects the H-Model, but is well described by the Class-Model. The Cold objects reject the H-Model, but the Class-Model (while not statistically rejected) also does not provide a compelling match for data. Although we formally reject models where the structure of the color distribution is a strong function of H magnitude, we also do not find that a simple dependence of color distribution on orbit classification is sufficient to describe the color distribution of classical KBOs.« less

Two Color Populations of Kuiper Belt and Centaur Objects

NASA Astrophysics Data System (ADS)

Tegler, Stephen C.; Romanishin, William; Consolmagno, Guy

2016-10-01

We present new optical colors for 64 Kuiper belt objects (KBOs) and Centaur objects measured with the 1.8-meter Vatican Advanced Technology Telescope (VATT) and the 4.3-meter Discovery Channel Telescope (DCT). By combining these new colors with our previously published colors, we increase the sample size of our survey to 154 objects. Our survey is unique in that the uncertainties in our color measurements are less than half the uncertainties in the color measurements reported by other researchers in the literature. Small uncertainties are essential for discerning between a unimodal and a bimodal distribution of colors for these objects as well as detecting correlations between colors and orbital elements. From our survey, it appears red Centaurs have a broader color distribution than grey Centaurs. We find red Centaurs have a smaller orbital inclination angle distribution than grey Centaurs at the 99.3% confidence level. Furthermore, we find that our entire sample of KBOs and Centaurs exhibits bimodal colors at the 99.4% confidence level. KBOs and Centaurs with HV > 7.0 have bimodal colors at the 99.96% confidence level and KBOs with HV < 6.0 have bimodal colors at the 96.3% confidence level.We are grateful to the NASA Solar System Observations Program for support, NAU for joining the Discovery Channel Telescope Partnership, and the Vatican Observatory for the consistent allocation of telescope time over the last 12 years of this project.

News and Views: Diamond is new head of SKA; Did you read our `A&G' mobile issue? BBC writer wins astro journalism prize; Kavli prize recognizes work on Kuiper Belt objects

NASA Astrophysics Data System (ADS)

2012-10-01

Philip Diamond will become director general of the Square Kilometre Array this month, moving from Australia to the new SKA headquarters at Jodrell Bank Radio Observatory. Technology writer Katia Moskvitch has won the first European Astronomy Journalism Prize for her series of articles on the Very Large Telescope at Paranal, Chile. Moskvitch will be the guest of the ESO at the inauguration of the Atacama Large Millimeter/submillimeter Array (ALMA) in the Atacama desert in March 2013. The 2012 Kavli Prize in Astrophysics is shared between David C Jewitt (University of California, USA), Jane X Luu (Massachusetts Institute of Technology, Lincoln Laboratory, USA), and Michael E Brown (California Institute of Technology, USA) “for discovering and characterizing the Kuiper Belt and its largest members, work that led to a major advance in the understanding of the history of our planetary system”.

Modeling Resonant Structure in the Kuiper Belt

NASA Astrophysics Data System (ADS)

Holmes, E. K.; Dermott, S. F.; Grogan, K.

1999-12-01

There is a possible connection between structure in circumstellar disks and the presence of planets, our own zodiacal cloud being the prime example. Asymmetries in such a disk could be diagnostic of planets which would be otherwise undetectable. At least three different types of asymmetries can serve to indicate bodies orbiting a star in a disk: (1) a warp in the plane of symmetry of the disk, (2) an offset in the center of symmetry of the disk with respect to the central star, and (3) density anomalies in the plane of the disk due to resonant trapping of dust particles. In the asteroid belt, collisions between asteroids supply dust particles to the zodiacal cloud. By comparison, it has been postulated that collisions between KBOs could initiate a collisional cascade which would produce a Kuiper dust disk. In fact, the Kuiper Belt is the region of our solar system that is most analogous to the planetary debris disks we see around other stars such as Vega, β Pic, Fomalhaut, and ɛ Eridani (Backman and Paresce 1993). A Kuiper Disk would most likely have a resonant structure, with two concentrations in brightness along the ecliptic longitude. This large scale structure arises because many of the KBOs, the Plutinos, are in the 2:3 mean motion resonance with Neptune. By running numerical integrations of particles in Pluto-like orbits, the resonant structure of the Kuiper belt can be studied by determining the percentage of particles trapped in the resonance as a function of their initial velocity and beta, where β = Frad}/F{grav. The dynamical evolution of the particles is followed from source to sink with Poynting Robertson light drag, solar wind drag, radiation pressure, and the effects of planetary gravitational perturbations included. This research was funded in part by a NASA GSRP grant.

Modeling Resonant Structure in the Kuiper Belt

NASA Astrophysics Data System (ADS)

Holmes, E. K.; Dermott, S. F.; Grogan, K.

1999-09-01

There is a possible connection between structure in circumstellar disks and the presence of planets, our own zodiacal cloud being the prime example. Asymmetries in such a disk could be diagnostic of planets which would be otherwise undetectable. At least three different types of asymmetries can serve to indicate bodies orbiting a star in a disk: (1) a warp in the plane of symmetry of the disk, (2) an offset in the center of symmetry of the disk with respect to the central star, and (3) density anomalies in the plane of the disk due to resonant trapping of dust particles. In the asteroid belt, collisions between asteroids supply dust particles to the zodiacal cloud. By comparison, it has been postulated that collisions between KBOs could initiate a collisional cascade which would produce a Kuiper dust disk. In fact, the Kuiper Belt is the region of our solar system that is most analogous to the planetary debris disks we see around other stars such as Vega, beta Pic, Fomalhaut, and epsilon Eridani (Backman and Paresce 1993). A Kuiper Disk would most likely have a resonant structure, with two concentrations in brightness along the ecliptic longitude. This large scale structure arises because many of the KBOs, the Plutinos, are in the 2:3 mean motion resonance with Neptune. By running numerical integrations of particles in Pluto-like orbits, the resonant structure of the Kuiper belt can be studied by determining the percentage of particles trapped in the resonance as a function of their initial velocity and beta, where beta = Frad/Fgrav. The dynamical evolution of the particles is followed from source to sink with Poynting Robertson light drag, solar wind drag, radiation pressure, and the effects of planetary gravitational perturbations included. This research was funded in part by a NASA GSRP grant.

Testing Backwards Integration As A Method Of Age-Determination for KBO Families

NASA Astrophysics Data System (ADS)

Benfell, Nathan; Ragozzine, Darin

2017-10-01

The age of young asteroid collisional families is often determined by using backwards n-body integration of the solar system. This method is not used for discovering young asteroid families and is limited by the unpredictable influence of the Yarkovsky effect on individual specific asteroids over time. Since these limitations are not as important for objects in the Kuiper belt Marcus et al. 2011 suggested that backwards integration could be used to discover and characterize collisional families in the outer solar system. However, there are some minor effects that may be important to include in the integration to ensure a faithful reproduction of the actual solar system. We have created simulated families of Kuiper Belt objects through a forwards integration of various objects with identical starting locations and velocity distributions, based on the Haumea family. After carrying this integration forwards through ~4 Gyr, backwards integrations are used (1) to investigate which factors are of enough significance to require inclusion in the integration (e.g., terrestrial planets, KBO self-gravity, putative Planet 9, etc.), (2) to test orbital element clustering statistics and identify methods for assessing false alarm probabilities, and (3) to compare the age estimates with the known age of the simulated family to explore the viability of backwards integration for precise age estimates.

NEPTUNE'S WILD DAYS: CONSTRAINTS FROM THE ECCENTRICITY DISTRIBUTION OF THE CLASSICAL KUIPER BELT

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawson, Rebekah I.; Murray-Clay, Ruth, E-mail: rdawson@cfa.harvard.edu

2012-05-01

Neptune's dynamical history shaped the current orbits of Kuiper Belt objects (KBOs), leaving clues to the planet's orbital evolution. In the 'classical' region, a population of dynamically 'hot' high-inclination KBOs overlies a flat 'cold' population with distinct physical properties. Simulations of qualitatively different histories for Neptune, including smooth migration on a circular orbit or scattering by other planets to a high eccentricity, have not simultaneously produced both populations. We explore a general Kuiper Belt assembly model that forms hot classical KBOs interior to Neptune and delivers them to the classical region, where the cold population forms in situ. First, wemore » present evidence that the cold population is confined to eccentricities well below the limit dictated by long-term survival. Therefore, Neptune must deliver hot KBOs into the long-term survival region without excessively exciting the eccentricities of the cold population. Imposing this constraint, we explore the parameter space of Neptune's eccentricity and eccentricity damping, migration, and apsidal precession. We rule out much of parameter space, except where Neptune is scattered to a moderately eccentric orbit (e > 0.15) and subsequently migrates a distance {Delta}a{sub N} = 1-6 AU. Neptune's moderate eccentricity must either damp quickly or be accompanied by fast apsidal precession. We find that Neptune's high eccentricity alone does not generate a chaotic sea in the classical region. Chaos can result from Neptune's interactions with Uranus, exciting the cold KBOs and placing additional constraints. Finally, we discuss how to interpret our constraints in the context of the full, complex dynamical history of the solar system.« less

In search of a signature of binary Kuiper Belt Objects in the Pluto-Charon crater population

NASA Astrophysics Data System (ADS)

Zangari, Amanda Marie; Parker, Alex; Singer, Kelsi N.; Stern, S. Alan; Young, Leslie; Olkin, Catherine B.; Ennico, Kimberly; Weaver, Harold A.; New Horizons Geology, Geophysics and Imaging Science Theme Team

2016-10-01

In July 2015, New Horizons flew by Pluto and Charon, allowing mapping of the encounter hemisphere at high enough resolution to produce crater counts from the surfaces of the pair. We investigate the distribution of craters in search of a signature of binary impactors. The Kuiper Belt -- especially the cold classical region -- has a large fraction of binary objects, many of which are close-in, equal-mass binaries. We will present results on how the distribution of craters seen on Pluto and Charon compares to a random distribution of single body impactors on the surfaces of each. Examining the surfaces of Pluto and Charon proves challenging due to resurfacing, and the presence of tectonic and other geographic features. For example, the informally-named Cthulhu region is among the oldest on Pluto, yet it abuts a craterless region millions of years young. On Charon, chastmata divide the surface into regions informally named Vulcan Planum and Oz terra. In our statistics, we pay careful attention to the boundaries of where craters may appear, and the dependence of our results on crater size. This work was supported by NASA's New Horizons project.

Circularizing Planet Nine through dynamical friction with an extended, cold planetesimal belt

NASA Astrophysics Data System (ADS)

Eriksson, Linn E. J.; Mustill, Alexander J.; Johansen, Anders

2018-04-01

Unexpected clustering in the orbital elements of minor bodies beyond the Kuiper belt has led to speculations that our Solar system actually hosts nine planets, the eight established plus a hypothetical `Planet Nine'. Several recent studies have shown that a planet with a mass of about 10 Earth masses on a distant eccentric orbit with perihelion far beyond the Kuiper belt could create and maintain this clustering. The evolutionary path resulting in an orbit such as the one suggested for Planet Nine is nevertheless not easily explained. Here, we investigate whether a planet scattered away from the giant-planet region could be lifted to an orbit similar to the one suggested for Planet Nine through dynamical friction with a cold, distant planetesimal belt. Recent simulations of planetesimal formation via the streaming instability suggest that planetesimals can readily form beyond 100 au. We explore this circularisation by dynamical friction with a set of numerical simulations. We find that a planet that is scattered from the region close to Neptune on to an eccentric orbit has a 20-30 per cent chance of obtaining an orbit similar to that of Planet Nine after 4.6 Gyr. Our simulations also result in strong or partial clustering of the planetesimals; however, whether or not this clustering is observable depends on the location of the inner edge of the planetesimal belt. If the inner edge is located at 200 au, the degree of clustering amongst observable objects is significant.

Detection of a Divot in the Scattering Population's Size Distribution

NASA Astrophysics Data System (ADS)

Shankman, Cory; Gladman, B.; Kaib, N.; Kavelaars, J.; Petit, J.

2012-10-01

Via joint analysis of the calibrated Canada France Ecliptic Place Survey (CFEPS, Petit et al 2011, AJ 142, 131), which found scattering Kuiper Belt objects, and models of their orbital distribution, we show that there should be enough kilometer-scale scattering objects to supply the Jupiter Family Comets (JFCs). Surprisingly, our analysis favours a divot (an abrupt drop and then recovery) in the size distribution at a diameter of 100 km, which results in a temporary flattening of the cumulative size distribution until it returns to a collisional equilibrium slope. Using the absolutely calibrated CFEPS survey we estimate that there are 2 x 10**9 scattering objects with H_g < 18, which is sufficient to provide the currently estimated JFC resupply rate. We also find that the primordial disk from which the scattering objects came must have had a "hot" initial inclination distribution before the giant planets scattered it out. We find that a divot, in the absolute magnitude number distribution, with a bright-end logarithmic slope of 0.8, a drop at a g-band H magnitude of 9, and a faint side logarithmic slope of 0.5 satisfies our data and simultaneously explains several existing nagging puzzles about Kuiper Belt luminosity functions (see Gladman et al., this meeting). Multiple explanations of how such a feature could have arisen will be discussed. This research was supported by the Natural Sciences and Engineering Research Council of Canada.

A Chemical and Dynamical Link Between Red Centaur Objects and the Cold Classical Kuiper Belt

NASA Astrophysics Data System (ADS)

Tegler, Stephen C.; Romanishin, William; Consolmagno, Guy

2015-11-01

We present new B-V, V-R, and B-R colors for 32 Centaurs objects using the 4.3-meter Discovery Channel Telescope (DCT) near Happy Jack, AZ and the 1.8-meter Vatican Advanced Technology Telescope on Mt. Graham, AZ. Combining these new colors with our previously reported colors, we now have optical broad-band colors for 58 Centaur objects.Application of the non-parametric Dip Test to our previous sample of only 26 objects showed Centaurs split into gray and red groups at the 99.5% confidence level, and application of the Wilcoxon Rank Sum Test to the same sample showed that red Centaurs have a higher median albedo than gray Centaurs at the 99% confidence level (Tegler et al., 2008, Solar System Beyond Neptune, U Arizona Press, pp. 105-114).Here we report application of the Wilcoxon Rank Sum Test to our sample of 58 Centaurs. We confirm red Centaurs have a higher median albedo than gray Centaurs at the 99.7% level. In addition, we find that red Centaurs have a lower median inclination angle than gray Centaurs at the 99.5% confidence level. Because of their red colors and lower inclination angles, we suggest red Centaurs originate in the cold classical Kuiper belt. We thank the NASA Solar System Observations Program for its support.

Silicate Phases on the Surfaces of Trojan Asteroids

NASA Astrophysics Data System (ADS)

Martin, Audrey; Emery, Joshua P.; Lindsay, Sean S.

2017-10-01

Determining the origin of asteroids provides an effective means of constraining the solar system’s dynamic past. Jupiter Trojan asteroids (hereafter Trojans) may help in determining the amount of radial mixing that occurred during giant planet migration. Previous studies aimed at characterizing surface composition show that Trojans have low albedo surfaces and are spectrally featureless in the near infrared. The thermal infrared (TIR) wavelength range has advantages for detecting silicates on low albedo asteroids such as Trojans. The 10 μm region exhibits strong features due to the Si-O fundamental molecular vibrations. Silicates that formed in the inner solar system likely underwent thermal annealing, and thus are crystalline, whereas silicates that accreted in the outer solar system experienced less thermal processing, and therefore are more likely to have remained in an amorphous phase. We hypothesize that the Trojans formed in the outer solar system (i.e., the Kuiper Belt), and therefore will have a more dominant amorphous spectral silicate component. With TIR spectra from the Spitzer Space Telescope, we identify mineralogical features from the surface of 11 Trojan asteroids. Fine-grain mixtures of crystalline pyroxene and olivine exhibit a 10 μm feature with sharp cutoffs between about 9 μm and 12 μm, which create a broad flat plateau. Amorphous phases, when present, smooth the sharp emission features, resulting in a dome-like shape. Preliminary results indicate that the surfaces of analyzed Trojans contain primarily amorphous silicates. Emissivity spectra of asteroids 1986 WD and 4709 Ennomos include small peaks in the 10 μm region, diagnostic of small amounts of crystalline olivine. One explanation is that Trojans formed in the same region as Kuiper Belt objects, and when giant planet migration ensued, they were swept into Jupiter’s stable Lagrange points where they are found today. As such, it is possible that an ancestral group of Kuiper Belt objects were separated from Trojans during large planet migration.

Planet Imager Discovers Young Kuiper Belt

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2015-07-01

A debris disk just discovered around a nearby star is the closest thing yet seen to a young version of the Kuiper belt. This disk could be a key to better understanding the interactions between debris disks and planets, as well as how our solar system evolved early on in its lifetime. Hunting for an analog The best way to understand how the Kuiper belt — home to Pluto and thousands of other remnants of early icy planet formation in our solar system — developed would be to witness a similar debris disk in an earlier stage of its life. But before now, none of the disks we've discovered have been similar to our own: the rings are typically too large, the central star too massive, or the stars exist in regions very unlike what we think our Sun's birthplace was like. A collaboration led by Thayne Currie (National Astronomical Observatory of Japan) has changed this using the Gemini Planet Imager (GPI), part of a new generation of extreme adaptive-optics systems. The team discovered a debris disk of roughly the same size as the Kuiper belt orbiting the star HD 115600, located in the nearest OB association. The star is only slightly more massive than our Sun, and it lives in a star-forming region similar to the early Sun's environment. HD 115600 is different in one key way, however: it is only 15 million years old. This means that observing it gives us the perfect opportunity to observe how our solar system might have behaved when it was much younger. A promising future GPI's spatially-resolved spectroscopy, combined with measurements of the reflectivity of the disk, have led the team to suspect that the disk might be composed partly of water ice, just as the Kuiper belt is. The disk also shows evidence of having been sculpted by the motions of giant planets orbiting the central star, in much the same way as the outer planets of our solar system may have shaped the Kuiper belt. The observations of HD 115600 are some of the very first to emerge from GPI and the new generation of planet-hunting instruments. The detection of this disk provides a promising outlook on what we can expect to discover in the future with these systems. Citation: Thayne Currie et al. 2015 ApJ 807 L7 doi:10.1088/2041-8205/807/1/L7

Studies of extra-solar Oort clouds and the Kuiper disk

NASA Technical Reports Server (NTRS)

Stern, S. Alan

1996-01-01

We are conducting research designed to enhance our understanding of the evolution and detectability of comet clouds and disks. According to 'standard' theory, both the Kuiper Belt and the Oort Cloud are (at least in part) natural products of the planetary accumulation stage of solar system formation. One expects such assemblages to be a common attribute of other solar systems. Therefore, searches for comet disks and clouds orbiting other stars offer a new method for inferring the presence of planetary systems. This project consists of two efforts: (1) observational work to predict and search for the signatures of Oort Clouds and comet disks around other stars; and (2) modelling studies of the formation and evolution of the Kuiper Belt (KB) and similar assemblages that may reside around other stars, including beta Pic.

Vega: Two Belts and the Possibility of Planets

NASA Image and Video Library

2013-01-08

In this diagram, the Vega system, which was already known to have a cooler outer belt of comets orange, is compared to our solar system with its asteroid and Kuiper belts. The ring of warm, rocky debris was detected using NASA Spitzer Space Telescope,

Artist Concept: Flying by a 2014 MU69

NASA Image and Video Library

2017-09-06

Artist's concept of the New Horizons spacecraft flying by a possible binary 2014 MU69 on Jan. 1, 2019. Early observations of MU69 hint at the Kuiper Belt object being either a binary orbiting pair or a contact (stuck together) pair of nearly like-sized bodies with diameters near 20 and 18 kilometers (12 and 11 miles). https://photojournal.jpl.nasa.gov/catalog/PIA21943

Modeling Kuiper belt objects Charon, Orcus and Salacia by means of a new equation of state for porous icy bodies

NASA Astrophysics Data System (ADS)

Malamud, Uri; Prialnik, Dina

2015-01-01

We use a one-dimensional adaptive-grid thermal evolution code to model Kuiper belt objects Charon, Orcus and Salacia and compare their measured bulk densities with those resulting from evolutionary calculations at the end of 4.6 Gyr. Our model assumes an initial homogeneous composition of mixed ice and rock, and follows the multiphase flow of water through the porous rocky medium, consequent differentiation and aqueous chemical alterations in the rock. Heating sources include long-lived radionuclides, serpentinization reactions, release of gravitational potential energy due to compaction, and crystallization of amorphous ice. The density profile is calculated by assuming hydrostatic equilibrium to be maintained through changes in composition, pressure and temperature. To this purpose, we construct an equation of state suitable for porous icy bodies with radii of a few hundred km, based on the best available empirical studies of ice and rock compaction, and on comparisons with rock porosities in Earth analog and Solar System silicates. We show that the observed bulk densities can be reproduced by assuming the same set of initial and physical parameters, including the same rock/ice mass ratio for all three bodies. We conclude that the mass of the object uniquely determines the evolution of porosity, and thus explains the observed differences in bulk density. The final structure of all three objects is differentiated, with an inner rocky core, and outer ice-enriched mantle. The degree of differentiation, too, is determined by the object's mass.

Wide-field investigation of the Kuiper Belt

NASA Astrophysics Data System (ADS)

Trujillo, Chadwick Aaron

Two wide-field surveys have been conducted for Kuiper Belt Objects (KBOs) and Centaurs using the largest close- packed CCD Mosaic cameras in the world. The first is a wide-field ecliptic survey of 157 square degrees to limiting red magnitude 21.1, responsible for the discovery of 3 KBOs and 1 Centaur. The second is a much deeper survey of 76 square degrees to limiting red magnitude 23.7, which found 86 KBOs. Data were analysed using the same software methods, and a maximum-likelihood simulation was used to debias the observations in a consistent manner. Fundamental quantities describing the Kuiper Belt are derived from these data: size distribution, inclination distribution, radial extent, and total mass. We find that the KBOs follow a differential power law size distribution with index q = 3.8 (+0.3, -0.4 1σ = 68.27% confidence), consistent with the crushed rock size distributions measured in hypervelocity impact experiments. In addition, the debiased inclinations of the Classical KBOs are consistent with a thick Gaussian distribution with half-width 20 (+8, -2 1σ) degrees. The Scattered KBOs are consistent with a Gaussian model with half-width 11 (+6, -3 1σ) degrees, with modal inclination 20 (+9, -4 1σ) degrees. The inclination measurements indicate that the KBOs are in a highly erosive state, with velocity dispersions of 1 to 2 kilometers per second. Strong evidence is presented for a truncation of the Classical KBOs at heliocentric distances beyond 50 AU. The total number and mass of the Scattered KBOs is about 3 times larger than that of the Classical KBOs, with a combined mass from the two populations of about 0.3 Earth masses.

Dynamics of the Trans-Neptune Region: Apsidal Waves in the Kuiper Belt

NASA Technical Reports Server (NTRS)

Ward, William R.; Hahn, Joseph M.

1998-01-01

The role of apsidal density waves propagating in a primordial trans-Neptune disk (i.e., Kuiper belt) is investigated. It is shown that Neptune launches apsidal waves at its secular resonance near 40 AU that propagate radially outward, deeper into the particle disk. The wavelength of apsidal waves is considerably longer than waves that might be launched at Lindblad resonances, because the pattern speed, g(sub s), resulting from the apsis precession of Neptune is much slower than its mean motion, Omega(sub s). If the early Kuiper belt had a sufficient surface density, sigma, the disk's wave response to Neptune's secular perturbation would have spread the disturbing torque radially over a collective scale lambda(sub *) approx. = r(2(mu)(sub d)Omega/ absolute value of r dg/dr)(sup 1/2), where mu(sub d)equivalent pi(sigma)r(exp 2)/(1 solar mass) and Omega(r) and g(r) are respectively the mean motion and precession frequency of the disk particles. This results in considerably smaller eccentricities at resonance than had the disk particles been treated as noninteracting test particles. Consequently, particles are less apt to be excited into planet-crossing orbits, implying that the erosion timescales reported by earlier test-particle simulations of the Kuiper belt may be underestimated. It is also shown that the torque the disk exerts upon the planet (due to its gravitational attraction for the disk's spiral wave pattern) damps the planet's eccentricity and further inhibits the planet's ability to erode the disk. Key words: celestial mechanics, stellar dynamics - comets: general minor planets, asteroids

Throwing Icebergs at White Dwarfs

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2017-08-01

Where do the metals come from that pollute the atmospheres of many white dwarfs? Close-in asteroids may not be the only culprits! A new study shows that distant planet-size and icy objects could share some of the blame.Pollution ProblemsArtists impression of rocky debris lying close around a white dwarf star. [NASA/ESA/STScI/G. Bacon]When a low- to intermediate-mass star reaches the end of its life, its outer layers are blown off, leaving behind its compact core. The strong gravity of this white dwarf causes elements heavier than hydrogen and helium to rapidly sink to its center in a process known as sedimentation, leaving an atmosphere that should be free of metallic elements.Therefore its perhaps surprising that roughly 2550% of all white dwarfs are observed to have atmospheric pollution by heavy elements. The short timescales for sedimentation suggest that these elements were added to the white dwarf recently but how did they get there?Bringing Ice InwardIn the generally accepted theory, pre-existing rocky bodies or an orbiting asteroid belt survive the stars evolution, later accreting onto the final white dwarf. But this scenario doesnt explain a few observations that suggest white dwarfs might be accreting larger planetary-size bodies and bodies with ices and volatile materials.Dynamical evolution of a Neptune-like planet (a) and a Kuiper belt analog object (b) in wide binary star systems. Both have large eccentricity excitations during the white dwarf phase. [Stephan et al. 2017]How might you get large or icy objects which would begin on very wide orbits close enough to a white dwarf to become disrupted and accrete? Led by Alexander Stephan, a team of scientists at UCLA now suggest that the key is for the white dwarf to be in a binary system.Influence of a CompanionIn the authors model, the white-dwarf progenitor is orbited by both a distant stellar companion (a common occurrence) and a number of large potential polluters, which could have masses between that of a large asteroid up to several times the mass of Jupiter. These potential polluters have very wide orbits that allow them to maintain ice and volatile materials.At the end of the progenitors lifetime it loses a significant amount of mass, causing the orbits of the surviving objects in the system to expand. After this stage, the stellar companion gravitationally perturbs the potential polluters onto extremely eccentric orbits, bringing these massive and long-period objects close enough accrete onto what is now the white dwarf.The Need for ObservationsThe likelihood distributions for orbital parameters of the systems that result in white dwarfs polluted by Neptune-like planets and Kuiper-belt-analog objects. The black arrows mark the parameters for one of the few observed systems, WD 1425+540, for comparison. [Stephan et al. 2017]By running large Monte Carlo simulations, Stephan and collaborators demonstrate that this scenario can successfully produce accretion of both Neptune-like planets and Kuiper-belt-analog objects. Their simulation results indicate that 1% of all white dwarfs should accrete Neptune-like planets, and 7.5% of all white dwarfs should accrete Kuiper-belt-analog objects.While these fractions are broadly consistent with observations, its hard to say with certainty whether this model is correct, as observations are scant. Only 200 polluted white dwarfs have been observed, and of these, only 15 have had detailed abundance measurements made. Next steps for understanding white-dwarf pollution certainly must includegathering more observations of polluted white dwarfs and establishing the statistics of what is polluting them.CitationAlexander P. Stephan et al 2017 ApJL 844 L16. doi:10.3847/2041-8213/aa7cf3

The formation of Kuiper-belt binaries through exchange reactions.

PubMed

Funato, Yoko; Makino, Junichiro; Hut, Piet; Kokubo, Eiichiro; Kinoshita, Daisuke

2004-02-05

Recent observations have revealed that an unexpectedly high fraction--a few per cent--of the trans-Neptunian objects (TNOs) that inhabit the Kuiper belt are binaries. The components have roughly equal masses, with very eccentric orbits that are wider than a hundred times the radius of the primary. Standard theories of binary asteroid formation tend to produce close binaries with circular orbits, so two models have been proposed to explain the unique characteristics of the TNOs. Both models, however, require extreme assumptions regarding the size distribution of the TNOs. Here we report a mechanism that is capable of producing binary TNOs with the observed properties during the early stages of their formation and growth. The only required assumption is that the TNOs were initially formed through gravitational instabilities in the protoplanetary dust disk. The basis of the mechanism is an exchange reaction in which a binary whose primary component is much more massive than the secondary interacts with a third body, whose mass is comparable to that of the primary. The low-mass secondary component is ejected and replaced by the third body in a wide but eccentric orbit.

SLOAN DIGITAL SKY SURVEY OBSERVATIONS OF KUIPER BELT OBJECTS: COLORS AND VARIABILITY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ofek, Eran O.

2012-04-10

Colors of trans-Neptunian objects (TNOs) are used to study the evolutionary processes of bodies in the outskirts of the solar system and to test theories regarding their origin. Here I describe a search for serendipitous Sloan Digital Sky Survey (SDSS) observations of known TNOs and Centaurs. I present a catalog of SDSS photometry, colors, and astrometry of 388 measurements of 42 outer solar system objects. I find weak evidence, at the Almost-Equal-To 2{sigma} level (per trial), for a correlation between the g - r color and inclination of scattered disk objects and hot classical Kuiper Belt objects. I find amore » correlation between the g - r color and the angular momentum in the z direction of all the objects in this sample. These findings should be verified using larger samples of TNOs. Light curves as a function of phase angle are constructed for 13 objects. The steepness of the slopes of these light curves suggests that the coherent backscatter mechanism plays a major role in the reflectivity of outer solar system small objects at small phase angles. I find weak evidence for an anticorrelation, significant at the 2{sigma} confidence level (per trial), between the g-band phase-angle slope parameter and the semimajor axis, as well as the aphelion distance, of these objects (i.e., they show a more prominent 'opposition effect' at smaller distances from the Sun). However, this plausible correlation should be verified using a larger sample. I discuss the origin of this possible correlation and argue that if this correlation is real it probably indicates that 'Sedna'-like objects have a different origin than other classes of TNOs. Finally, I identify several objects with large variability amplitudes.« less

RTO Technical Publications: A Quarterly Listing

NASA Technical Reports Server (NTRS)

2004-01-01

The titles of five reports are listed here, together with an abstract for each. The titles include: 1) 'Spectral Models of Kuiper Belt Objects and Centaurs'; 2) 'Simulation of and for Military Decision Making'; 3) 'Abundance of the Radioactive Be-10 in the Cosmic Radiation up to 2 GeV/nucleon with the Balloon-borne Instrument ISOMAX1998'; 4) 'Optical Air Flow Measurements in Flight'; 5) 'Flight Test Measurement Techniques for Laminar Flow'.

Origins Space Telescope: Solar System Science

NASA Astrophysics Data System (ADS)

Wright, Edward L.; Origins Space Telescope Study Team

2017-01-01

The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its imagers and spectrographs will enable a variety of surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu.In the Solar System, OST will provide km/sec resolution on lines from planet, moons and comets. OST will measure molecular abundances and isotope ratios in planets and comets. OST will be able to do continuum surveys for faint moving sources such as Kuiper Belt Objects, enabling a census of smaller objects in the Kuiper Belt. If the putative Planet IX is massive enough to be self-luminous, then OST will be able to detect it out to thousands of AU from the Sun.

Will new horizons see dust clumps in the Edgeworth-Kuiper Belt?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vitense, Christian; Krivov, Alexander V.; Löhne, Torsten, E-mail: vitense@astro.uni-jena.de

2014-06-01

Debris disks are thought to be sculptured by neighboring planets. The same is true for the Edgeworth-Kuiper debris disk, yet no direct observational evidence for signatures of giant planets in the Kuiper Belt dust distribution has been found so far. Here we model the dust distribution in the outer solar system to reproduce the dust impact rates onto the dust detector on board the New Horizons spacecraft measured so far and to predict the rates during the Neptune orbit traverse. To this end, we take a realistic distribution of trans-Neptunian objects to launch a sufficient number of dust grains ofmore » different sizes and follow their orbits by including radiation pressure, Poynting-Robertson and stellar wind drag, as well as the perturbations of four giant planets. In a subsequent statistical analysis, we calculate number densities and lifetimes of the dust grains in order to simulate a collisional cascade. In contrast to the previous work, our model not only considers collisional elimination of particles but also includes production of finer debris. We find that particles captured in the 3:2 resonance with Neptune build clumps that are not removed by collisions, because the depleting effect of collisions is counteracted by production of smaller fragments. Our model successfully reproduces the dust impact rates measured by New Horizons out to ≈23 AU and predicts an increase of the impact rate of about a factor of two or three around the Neptune orbit crossing. This result is robust with respect to the variation of the vaguely known number of dust-producing scattered disk objects, collisional outcomes, and the dust properties.« less

VizieR Online Data Catalog: Orbital parameters of Kuiper Belt objects (Volk+, 2017)

NASA Astrophysics Data System (ADS)

Volk, K.; Malhotra, R.

2017-11-01

Our starting point is the list of minor planets in the outer solar system cataloged in the database of the Minor Planet Center (http://www.minorplanetcenter.net/iau/lists/t_centaurs.html and http://www.minorplanetcenter.net/iau/lists/t_tnos.html) as of 2016 October 20. The complete listing of our sample, including best-fit orbital parameters and sky locations, is provided in Table1. (1 data file).

Operation of the University of Hawaii 2.2M Telescope on Mauna Kea

NASA Technical Reports Server (NTRS)

McLaren, Robert A.

1999-01-01

This paper presents a final report from March 1, 1997-February 28, 1999 on the Operation of the University of Hawaii 2.2M Telescope on Mauna Kea. The topics include: 1) Telescope and Instrumentation (Newsletter and Documentation, Scheduling Periods); and 2) Scientific Highlights (The Outer Solar System-Trans-Neptunian Objects and the Kuiper Belt, Comet Hale-Bopp, Near-Earth Asteroids, Asteroid Families, and Galileo Mission Support).

VOLATILE LOSS AND CLASSIFICATION OF KUIPER BELT OBJECTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Johnson, R. E.; Schmidt, C.; Oza, A.

Observations indicate that some of the largest Kuiper Belt Objects (KBOs) have retained volatiles in the gas phase (e.g., Pluto), while others have surface volatiles that might support a seasonal atmosphere (e.g., Eris). Since the presence of an atmosphere can affect their reflectance spectra and thermal balance, Schaller and Brown examined the role of volatile escape driven by solar heating of the surface. Guided by recent simulations, we estimate the loss of primordial N{sub 2} for several large KBOs, accounting for escape driven by UV/EUV heating of the upper atmosphere as well as by solar heating of the surface. Formore » the latter we present new simulations and for the former we scale recent detailed simulations of escape from Pluto using the energy limited escape model validated recently by molecular kinetic simulations. Unlike what has been assumed to date, we show that unless the N{sub 2} atmosphere is thin (<∼10{sup 18} N{sub 2} cm{sup −2}) and/or the radius small (<∼200–300 km), escape is primarily driven by the UV/EUV radiation absorbed in the upper atmosphere. This affects the discussion of the relationship between atmospheric loss and the observed surface properties for a number of the KBOs examined. Our long-term goal is to connect detailed atmospheric loss simulations with a model for volatile transport for individual KBOs.« less

A Search for Satellites of Kuiper Belt Object 55636 from the 2009 October 9 Occultation

NASA Astrophysics Data System (ADS)

Jensen-Clem, Rebecca; Elliot, J. L.; Person, M. J.; Zuluaga, C. A.; Bosh, A. S.; Adams, E. R.; Brothers, T. C.; Gulbis, A. A. S.; Levine, S. E.; Lockhart, M.; Zangari, A. M.; Babcock, B. A.; DuPre, K.; Pasachoff, J. M.; Souza, S. P.; Rosing, W.; Secrest, N.; Bright, L.; Dunham, E. W.; Kakkala, M.; Tilleman, T.; Rapoport, S.; Zambrano-Marin, L.; Wolf, J.; Morzinski, K.

2011-01-01

A world-wide observing campaign of 21 telescopes at 18 sites was organized by Elliot et al. (2010 Nature 465, 897) to observe the 2009 Oct. 9 stellar occultation of 2UCAC 41650964 (UCAC2 magnitude 13.1) by the Kuiper Belt object 55636 (visual magnitude 19.6). Integration times varied between 0.05 seconds at the Vatican Advanced Technology Telescope and 5 seconds at Mauna Kea mid-level. Data from the two sites that successfully observed the occultation (Haleakala and the Mauna Kea mid-level) were analyzed by Elliot et al. (2010) to determine the diameter and albedo of 55636. In this study, we use the entire data set to search for signatures of occultations by nearby satellites. One satellite previously discovered with occultation data is Neptune's moon Larissa, which was detected during Neptune's close approach to a star in 1982 (Reitsema et al. 1982). No satellites are found in this study, and upper limits will be reported on satellite radii within the volume probed (2 x 10-8 of the Hill Sphere). This work was supported, in part, by NASA Grants NNX10AB27G (MIT), NNX08AO50G (Williams College), and NNH08AI17I (USNO-FS) and NSF Grant AST-0406493 (MIT). Student participation was supported in part by NSF's REU program and NASA's Massachusetts Space Grant.

Thermal evolution of cometary nuclei

NASA Astrophysics Data System (ADS)

Prialnik, D.

2014-07-01

Thermal modeling of comet nuclei and similar objects involves the solution of conservation equations for energy and masses of the various components over time. For simplicity, the body is generally, but not necessarily, assumed to be of spherical shape. The processes included in such calculations are heat transfer, gas flow, dust drag, phase transitions, internal heating by various sources, internal structure alterations, surface sublimation. Physical properties --- such as the thermal conductivity, permeability, material strength, and porous structure --- are assumed, based on the best available estimates from laboratory experiments and space-mission results. Calculations employ various numerical procedures and require significant computational power, data analysis, and often sophisticated methods of graphical presentation. They start with a body of given size, mass, and composition, as well as a given orbit. The results yield properties and activity patterns that can be confronted with observations. Initial parameters may be adjusted until agreement is achieved. A glimpse into the internal structure of the object, which is inaccessible to direct observation, is thus obtained. The last decade, since the extensive overview of the subject was published (Modeling the structure and activity of comet nuclei, Prialnik, D.; Benkhoff, J.; Podolak, M., in Comets II, M. C. Festou, H. U. Keller, and H. A. Weaver, eds., University of Arizona Press, Tucson, p.359-387), thermal modeling has significantly advanced. This was prompted both by new properties and phenomena gleaned from observations, one example being main-belt comets, and the continual increase in computational power and performance. Progress was made on two fronts. On the computational side, multi-dimensional models have been developed, adaptive-grid and moving-boundaries techniques have been adopted, and long-term evolutionary calculations have become possible, even spanning the lifetime of the Solar System. On the chemo-physical side, additional chemical processes like serpentinization, and formation and decompositions of clathrates have been investigated. Special efforts have been devoted to related classes of objects: main-belt comets, Centaurs, Kuiper-belt objects and also to other ice-rich bodies, such as icy satellites. Since some of these objects are sufficiently large for hydrostatic pressure to become important, hydrostatic equilibrium was introduced into the modeling. This required the addition of an appropriate equation of state. Interesting new results have thus been obtained: retention of ice in the deep interior of main-belt comets over the age of the Solar System, differentiation between core and mantle in the larger Kuiper-belt objects, and complex patterns of outburst for active comets, simulating observed ones.

Trojan Binaries

NASA Astrophysics Data System (ADS)

Noll, K. S.

2017-12-01

The Jupiter Trojans, in the context of giant planet migration models, can be thought of as an extension of the small body populations found beyond Neptune in the Kuiper Belt. Binaries are a distinctive feature of small body populations in the Kuiper Belt with an especially high fraction apparent among the brightest Cold Classicals. The binary fraction, relative sizes, and separations in the dynamically excited populations (Scattered, Resonant) reflects processes that may have eroded a more abundant initial population. This trend continues in the Centaurs and Trojans where few binaries have been found. We review new evidence including a third resolved Trojan binary and lightcurve studies to understand how the Trojans are related to the small body populations that originated in the outer protoplanetary disk.

Numerical Simulations Of Catastrophic Disruption Of Porous Bodies: Application To Dark-type Asteroids And Kuiper-belt Family Formation

NASA Astrophysics Data System (ADS)

Michel, Patrick; Jutzi, M.; Richardson, D. C.; Benz, W.

2010-10-01

Asteroids of dark (e.g. C, D) taxonomic classes as well as Kuiper Belt objects and comets are believed to have high porosity, not only in the form of large voids but also in the form of micro-pores. The presence of such microscale porosity introduces additional physics in the impact process. We have enhanced our 3D SPH hydrocode, used to simulate catastrophic breakups, with a model of porosity [1] and validated it at small scale by comparison with impact experiments on pumice targets [2]. Our model is now ready to be applied to a large range of problems. In particular, accounting for the gravitational phase of an impact, we can study the formation of dark-type asteroid families, such as Veritas, and Kuiper-Belt families, such as Haumea. Recently we characterized for the first time the catastrophic impact energy threshold, usually called Q*D, as a function of the target's diameter, porosity, material strength and impact speed [3]. Regarding the mentioned families, our preliminary results show that accounting for porosity leads to different outcomes that may better represent their properties and constrain their definition. In particular, for Veritas, we find that its membership may need some revision [4]. The parameter space is still large, many interesting families need to be investigated and our model will be applied to a large range of cases. PM, MJ and DCR acknowledge financial support from the French Programme National de Planétologie, NASA PG&G "Small Bodies and Planetary Collisions" and NASA under Grant No. NNX08AM39G issued through the Office of Space Science, respectively. [1] Jutzi et al. 2008. Icarus 198, 242-255; [2] Jutzi et al. 2009. Icarus 201, 802-813; [3] Jutzi et al. 2010. Fragment properties at the catastrophic disruption threshold: The effect of the parent body's internal structure, Icarus 207, 54-65; [4] Michel et al. 2010. Icarus, submitted.

Origin and evolution of two-component debris discs and an application to the q1 Eridani system

NASA Astrophysics Data System (ADS)

Schüppler, Christian; Krivov, Alexander V.; Löhne, Torsten; Booth, Mark; Kirchschlager, Florian; Wolf, Sebastian

2016-09-01

Many debris discs reveal a two-component structure, with an outer Kuiper-belt analogue and a warm inner component whose origin is still a matter of debate. One possibility is that warm emission stems from an `asteroid belt' closer in to the star. We consider a scenario in which a set of giant planets is formed in an initially extended planetesimal disc. These planets carve a broad gap around their orbits, splitting up the disc into the outer and the inner belts. After the gas dispersal, both belts undergo collisional evolution in a steady-state regime. This scenario is explored with detailed collisional simulations involving realistic physics to describe a long-term collisional depletion of the two-component disc. We find that the inner disc may be able to retain larger amounts of material at older ages than thought before on the basis of simplified analytic models. We show that the proposed scenario is consistent with a suite of thermal emission and scattered light observational data for a bright two-temperature debris disc around a nearby solar-type star q1 Eridani. This implies a Solar system-like architecture of the system, with an outer massive `Kuiper belt', an inner `asteroid belt', and a few Neptune- to Jupiter-mass planets in between.

Epsilon Eridani Inner Asteroid Belt

NASA Image and Video Library

2017-09-14

SCI2017_0004: Artist's illustration of the Epsilon Eridani system showing Epsilon Eridani b, right foreground, a Jupiter-mass planet orbiting its parent star at the outside edge of an asteroid belt. In the background can be seen another narrow asteroid or comet belt plus an outermost belt similar in size to our solar system's Kuiper Belt. The similarity of the structure of the Epsilon Eridani system to our solar system is remarkable, although Epsilon Eridani is much younger than our sun. SOFIA observations confirmed the existence of the asteroid belt adjacent to the orbit of the Jovian planet. Credit: NASA/SOFIA/Lynette Cook

Sedna Orbit Animation

NASA Technical Reports Server (NTRS)

2004-01-01

This animation shows the location of the newly discovered planet-like object, dubbed 'Sedna,' in relation to the rest of the solar system. Starting at the inner solar system, which includes the orbits of Mercury, Venus, Earth, and Mars (all in yellow), the view pulls away through the asteroid belt and the orbits of the outer planets beyond (green). Pluto and the distant Kuiper Belt objects are seen next until finally Sedna comes into view. As the field widens the full orbit of Sedna can be seen along with its current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. Moving past Sedna, what was previously thought to be the inner edge of the Oort cloud appears. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

Radiolytic Gas-Driven Cryovolcanism in the Outer Solar System

NASA Technical Reports Server (NTRS)

Cooper, John F.; Cooper, Paul D.; Sittler, Edward C.; Sturner, Steven J.; Rymer, Abigail M.; Hill, Matthew E.

2007-01-01

Water ices in surface crusts of Europa, Enceladus, Saturn's main rings, and Kuiper Belt Objects can become heavily oxidized from radiolytic chemical alteration of near-surface water ice by space environment irradiation. Oxidant accumulations and gas production are manifested in part through observed H2O2 on Europa. tentatively also on Enceladus, and found elsewhere in gaseous or condensed phases at moons and rings of Jupiter and Saturn. On subsequent chemical contact in sub-surface environments with significant concentrations of primordially abundant reductants such as NH3 and CH4, oxidants of radiolytic origin can react exothermically to power gas-driven cryovolcanism. The gas-piston effect enormously amplifies the mass flow output in the case of gas formation at basal thermal margins of incompressible fluid reservoirs. Surface irradiation, H2O2 production, NH3 oxidation, and resultant heat, gas, and gas-driven mass flow rates are computed in the fluid reservoir case for selected bodies. At Enceladus the oxidant power inputs are comparable to limits on nonthermal kinetic power for the south polar plumes. Total heat output and plume gas abundance may be accounted for at Enceladus if plume activity is cyclic in high and low "Old Faithful" phases, so that oxidants can accumulate during low activity phases. Interior upwelling of primordially abundant NH3 and CH4 hydrates is assumed to resupply the reductant fuels. Much lower irradiation fluxes on Kuiper Belt Objects require correspondingly larger times for accumulation of oxidants to produce comparable resurfacing, but brightness and surface composition of some objects suggest that such activity may be ongoing.

Visible Near-infrared Spectral Evolution of Irradiated Mixed Ices and Application to Kuiper Belt Objects and Jupiter Trojans

NASA Astrophysics Data System (ADS)

Poston, Michael J.; Mahjoub, Ahmed; Ehlmann, Bethany L.; Blacksberg, Jordana; Brown, Michael E.; Carlson, Robert W.; Eiler, John M.; Hand, Kevin P.; Hodyss, Robert; Wong, Ian

2018-04-01

Understanding the history of Kuiper Belt Objects and Jupiter Trojans will help to constrain models of solar system formation and dynamical evolution. Laboratory simulations of a possible thermal and irradiation history of these bodies were conducted on ice mixtures while monitoring their spectral properties. These simulations tested the hypothesis that the presence or absence of sulfur explains the two distinct visible near-infrared spectral groups observed in each population and that Trojans and KBOs share a common formation location. Mixed ices consisting of water, methanol, and ammonia, in mixtures both with and without hydrogen sulfide, were deposited and irradiated with 10 keV electrons. Deposition and initial irradiation were performed at 50 K to simulate formation at 20 au in the early solar system, then heated to Trojan-like temperatures and irradiated further. Finally, irradiation was concluded and resulting samples were observed during heating to room temperature. Results indicated that the presence of sulfur resulted in steeper spectral slopes. Heating through the 140–200 K range decreased the slopes and total reflectance for both mixtures. In addition, absorption features at 410, 620, and 900 nm appeared under irradiation, but only in the H2S-containing mixture. These features were lost with heating once irradiation was concluded. While the results reported here are consistent with the hypothesis, additional work is needed to address uncertainties and to simulate conditions not included in the present work.

Dynamical implantation of objects in the Kuiper Belt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brasil, P. I. O.; Nesvorný, D.; Gomes, R. S., E-mail: pedro_brasil87@hotmail.com, E-mail: davidn@boulder.swri.edu, E-mail: rodney@on.br

Several models have been suggested in the past to describe the dynamical formation of hot Kuiper Belt objects (hereafter Hot Classicals or HCs for short). Here, we discuss a dynamical mechanism that allows orbits to evolve from the primordial planetesimal disk at ≲ 35 AU to reach the orbital region now occupied by HCs. We performed three different sets of numerical simulations to illustrate this mechanism. Two of these simulations were based on modern theories for the early evolution of the solar system (the Nice and jumping-Jupiter models). The third simulation was performed with the purpose of increasing the resolutionmore » at 41-46 AU. The common aspect of these simulations is that Neptune scatters planetesimals from ≲ 35 AU to >40 AU and then undergoes a long phase of slow residual migration. Our results show that to reach an HC orbit, a scattered planetesimal needs to be captured in a mean motion resonance (MMR) with Neptune where the perihelion distance rises due to the Kozai resonance (which occurs in MMRs even for moderate inclinations). Finally, while Neptune is still migrating, the planetesimal is released from the MMR on a stable HC orbit. We show that the orbital distribution of HCs expected from this process provides a reasonable match to observations. The capture efficiency and the mass deposited into the HC region appears to be sensitive to the maximum eccentricity reached by Neptune during the planetary instability phase. Additional work will be needed to resolve this dependency in detail.« less

Testing Migration of the Jupiter Trojan Asteroids in the Lab

NASA Astrophysics Data System (ADS)

Poston, Michael; Blacksberg, Jordana; Brown, Mike; Carey, Elizabeth; Carlson, Robert; Ehlmann, Bethany; Eiler, John; Hand, Kevin; Hodyss, Robert; Mahjoub, Ahmed; Wong, Ian

2015-11-01

Today’s Jupiter Trojan asteroids may have orininated in the Kuiper Belt (eg. Morbidelli et al. Nature 2005, Nesvorny et al. ApJ 2013) and migrated to capture at their present locations. If this is the case, it is expected that their surfaces will contain chemical traces of this history. No distinct spectral bands have been conclusively identified in the literature, however, visible and near-infrared spectra of Kuiper Belt, Centaur, and Trojan populations each show two sub-populations distinguished by their spectral slopes (Brown et al. ApJL 2011; Emery et al. AJ 2011). The slopes are all positive (or “red”), steepest in the Kuiper Belt, and least steep in the Trojan population. Here we test the hypothesis that the asteroids formed spanning a stability line for a critical substance; in this case we test sulfur, as H2S. The hypothesis is that irradiating mixed ices containing H2S will result in a refractory residue of steeper slope than the same composition without the H2S. We have simulated this history in the Minos chamber at the Icy Worlds Simulation Laboratory at NASA’s Jet Propulsion Laboratory. Ices that will be discussed include a 3:3:3:1 mixture of H2S: NH3: CH3OH: H2O and a 3:3:1 mixture of NH3: CH3OH: H2O. After deposition at 50 K, the ices were irradiated with a beam of 10 keV electrons to form the refractory crust. The ices were then warmed (while continuing irradiation) to 120 K and observed for several days. Reflectance spectra were collected throughout the experiment in the visible and infrared. The spectral slope increased dramatically after irradiation of the mixture containing H2S, while the spectral slope for the mixture without any sulfur changed very little. This is consistent with sulfur being the critical component determining which of the spectral populations an object belongs to in the present inventory of outer solar system objects. Quantitative analysis is underway.This work has been supported by the Keck Institute for Space Studies (KISS). The research described here was carried out at the Jet Propulsion Laboratory, Caltech, under a contract with the National Aeronautics and Space Administration (NASA) and at the Caltech Division of Geological and Planetary Sciences.

Dynamical Classifications of the Kuiper Belt

NASA Astrophysics Data System (ADS)

Maggard, Steven; Ragozzine, Darin

2018-04-01

The Minor Planet Center (MPC) contains a plethora of observational data on thousands of Kuiper Belt Objects (KBOs). Understanding their orbital properties refines our understanding of the formation of the solar system. My analysis pipeline, BUNSHIN, uses Bayesian methods to take the MPC observations and generate 30 statistically weighted orbital clones for each KBO that are propagated backwards along their orbits until the beginning of the solar system. These orbital integrations are saved as REBOUND SimulationArchive files (Rein & Tamayo 2017) which we will make publicly available, allowing many others to perform statistically-robust dynamical classification or complex dynamical investigations of outer solar system small bodies.This database has been used to expand the known collisional family members of the dwarf planet Haumea. Detailed orbital integrations are required to determine the dynamical distances between family members, in the form of "Delta v" as measured from conserved proper orbital elements (Ragozzine & Brown 2007). Our preliminary results have already ~tripled the number of known Haumea family members, allowing us to show that the Haumea family can be identified purely through dynamical clustering.We will discuss the methods associated with BUNSHIN and the database it generates, the refinement of the updated Haumea family, a brief search for other possible clusterings in the outer solar system, and the potential of our research to aid other dynamicists.

Wink of a Star

NASA Image and Video Library

2017-07-19

NASA's New Horizons team trained mobile telescopes on an unnamed star (circled) from a remote area of Argentina on July 17, 2017. A Kuiper Belt object 4.1 billion miles from Earth -- known as 2014 MU69 -- briefly blocked the light from the background star, in what's known as an occultation. The time difference between frames is 200 milliseconds, or 0.2 seconds. This data will help scientists better measure the shape, size and environment around the object. The New Horizons spacecraft will fly by this ancient relic of solar system formation on Jan. 1, 2019. It will be the most distant object ever explored by a spacecraft. A video is available at https://photojournal.jpl.nasa.gov/catalog/PIA21865

An Empirical Planetesimal Belt Radius–Stellar Luminosity Relation

NASA Astrophysics Data System (ADS)

Matrà, L.; Marino, S.; Kennedy, G. M.; Wyatt, M. C.; Öberg, K. I.; Wilner, D. J.

2018-05-01

Resolved observations of millimeter-sized dust, tracing larger planetesimals, have pinpointed the location of 26 Edgeworth–Kuiper Belt analogs. We report that a belt’s distance R to its host star correlates with the star’s luminosity L ⋆, following R\\propto {L}\\star 0.19 with a low intrinsic scatter of ∼17%. Remarkably, our Edgeworth–Kuiper Belt in the solar system and the two CO snow lines imaged in protoplanetary disks lie close to this R–L ⋆ relation, suggestive of an intrinsic relationship between protoplanetary disk structures and belt locations. To test the effect of bias on the relation, we use a Monte Carlo approach and simulate uncorrelated model populations of belts. We find that observational bias could produce the slope and intercept of the R–L ⋆ relation but is unable to reproduce its low scatter. We then repeat the simulation taking into account the collisional evolution of belts, following the steady-state model that fits the belt population as observed through infrared excesses. This significantly improves the fit by lowering the scatter of the simulated R–L ⋆ relation; however, this scatter remains only marginally consistent with the one observed. The inability of observational bias and collisional evolution alone to reproduce the tight relationship between belt radius and stellar luminosity could indicate that planetesimal belts form at preferential locations within protoplanetary disks. The similar trend for CO snow line locations would then indicate that the formation of planetesimals or planets in the outer regions of planetary systems is linked to the volatility of their building blocks, as postulated by planet formation models.

Identification of water ice on the Centaur 1997 CU26.

PubMed

Brown, R H; Cruikshank, D P; Pendleton, Y; Veeder, G J

1998-05-29

Spectra of the Centaur 1997 CU26 were obtained at the Keck Observatory on 27 October 1997 (universal time). The data show strong absorptions at 1.52 and 2.03 micrometers attributable to water ice on the surface of 1997 CU26. The reflectance spectrum of 1997 CU26 is matched by the spectrum of a mixture of low-temperature, particulate water ice and spectrally featureless but otherwise red-colored material. Water ice dominates the spectrum of 1997 CU26, whereas methane or methane-like hydrocarbons apparently dominate the spectrum of the Kuiper belt object 1993 SC, perhaps indicating different origins, thermal histories, or both for these two objects.

Ways of Changing the Number and Size Distribution of Ecliptic Comets

NASA Astrophysics Data System (ADS)

Dones, Henry C. Luke; Womack, Maria; Alvarellos, Jose; Bierhaus, Edward B.; Bottke, William; Hamill, Patrick; Nesvorny, David; Robbins, Stuart J.; Zahnle, Kevin

2017-06-01

The existence of the Kuiper Belt was proposed because of the need for a low-inclination source for the Jupiter-family comets (JFCs). Indeed, the Kuiper Belt is thought to be the main reservoir of ecliptic comets (ECs), which include the JFCs and Centaurs. Ironically, we still do not know whether the belt, specifically its Scattered Disk, provides an adequate source for the ECs (Volk and Malhotra 2008). ECs are also thought to be the main source of Sun-orbiting impactors on the regular moons of the giant planets (Zahnle et al. 2003 [Z03]). Some models of the cometary orbital distribution used by Z03 and others to estimate impact rates assume comets are indestructible; in fact, many cometssplit, sometimes far from the Sun (Fernández 2009). Assuming shatterproof comets may lead to incorrect results for cometary orbital distributions. Other models impose a physical lifetime for bodies that approach within ~3 AU of the Sun, where sublimation of water ice begins, after which a comet is assumed to be dormant or disrupted (Nesvorný et al. 2017). In reality, some comets (e.g., 29P, Hale-Bopp) are active due to volatiles such as CO and CO2 beyond the orbit of Jupiter (Womack et al. 2017). 174P/Echeclus underwent a 7-magnitude outburst 13 AU from the Sun (Rousselot et al. 2016), and CO emission was recently detected from Echeclus at 6 AU (Wierzchos et al. 2017). We will estimate the effects of several mechanisms on the number and size distribution of comet nuclei as a function of distance from the Sun, including cometary activity and spontaneous disruption; tidal disruption by a giant planet, as happened for Shoemaker-Levy 9; and tidal disruption of binaries, which are numerous among "cold classical" Kuiper Belt Objects (Fraser et al. 2017). We thank the Cassini Data Analysis Program for support.Fernández Y (2009). Planet. Space. Sci. 57, 1218.Fraser WC, et al. (2017). Nat. Astron. 1, 0088.Nesvorný D, et al. (2017). In preparation.Rousselot P, et al. (2016). MNRAS 462, S432.Volk K, Malhotra R (2008). Astrophys. J. 687, 714.Wierzchos K, Womack M, Sarid G. (2017). Astron. J., in press.Womack M, Sarid G, Wierzchos, K (2017). Publ. Astron. Soc. Pac. 129, 031001.Zahnle K, et al. (2003). Icarus 163, 263.

Probing the debris disks of nearby stars with Fermi-LAT

NASA Astrophysics Data System (ADS)

Riley, Alexander; Strigari, Louis; Porter, Troy; Blandford, Roger

2018-01-01

Many nearby stars are known to host circumstellar debris disks, similar to our Sun's asteroid and Kuiper belts, that are believed to be the birthplace of extrasolar planets. The bodies in these objects passively emit gamma radiation resulting from interactions with cosmic rays, as previously observed from measurements of the gamma ray albedo of the Moon. We apply a point source analysis to four nearby debris disks using the past nine years of data taken by Fermi-LAT, and report on the updated prospects for detecting gamma-ray emission from these sources.

Volume Ice Radiolysis in the Outer Solar System

NASA Technical Reports Server (NTRS)

Cooper, John F.; Cooper, Paul D.

2006-01-01

The primary energy flux of charged particle components of the heliospheric and magnetospheric environments of the solar system is primarily carried by highly penetrating energetic particles. Although laboratory experiments on production of organics and oxidants typically only address effects on very thin surface layers, energy deposition occurs on surfaces of icy bodies of the outer solar system to meters in depth. Time scales for significant radiolytic deposition vary from thousands of years at millimeter depths on Europa to billions of years in the meters-deep regolith of Kuiper Belt Objects. Radioisotope decay (e.g., K-40) also contributes to volume radiolysis as the only energy source at much greater depths. Radiolytic oxygen is a potential resource for life within Europa and a partial source of oxygen for Saturn's magnetosphere and Titan's upper atmosphere. Interactions of very high energy cosmic rays with ices at Titan's surface may provide one of the few sources of oxidants in that highly reducing environment. The red colors of low-inclination classical Kuiper Belt Objects at 40-50 AU, and Centaur objects originating from this same population, may arise from volume radiolysis of deep ice layers below more refractory radiation crusts eroded away by surface sputtering and micrometeoroid impacts. A variety of techniques are potentially available to measure volume radiolysis products and have been proposed for study as part of the new Space Physics of Life initiative at NASA Goddard Space Flight Center. The technique of Electron Paramagnetic Resonance (EPR) has been used in medical studies to measure oxidant production in irradiated human tissue for cancer treatment. Other potential techniques include optical absorption spectroscopy and standard wet chemical analysis. These and other potential techniques are briefly reviewed for applicability to problems in solar system ice radiolysis and astrobiology.

Craters of the Pluto-Charon system

NASA Astrophysics Data System (ADS)

Robbins, Stuart J.; Singer, Kelsi N.; Bray, Veronica J.; Schenk, Paul; Lauer, Tod R.; Weaver, Harold A.; Runyon, Kirby; McKinnon, William B.; Beyer, Ross A.; Porter, Simon; White, Oliver L.; Hofgartner, Jason D.; Zangari, Amanda M.; Moore, Jeffrey M.; Young, Leslie A.; Spencer, John R.; Binzel, Richard P.; Buie, Marc W.; Buratti, Bonnie J.; Cheng, Andrew F.; Grundy, William M.; Linscott, Ivan R.; Reitsema, Harold J.; Reuter, Dennis C.; Showalter, Mark R.; Tyler, G. Len; Olkin, Catherine B.; Ennico, Kimberly S.; Stern, S. Alan; New Horizons Lorri, Mvic Instrument Teams

2017-05-01

NASA's New Horizons flyby mission of the Pluto-Charon binary system and its four moons provided humanity with its first spacecraft-based look at a large Kuiper Belt Object beyond Triton. Excluding this system, multiple Kuiper Belt Objects (KBOs) have been observed for only 20 years from Earth, and the KBO size distribution is unconstrained except among the largest objects. Because small KBOs will remain beyond the capabilities of ground-based observatories for the foreseeable future, one of the best ways to constrain the small KBO population is to examine the craters they have made on the Pluto-Charon system. The first step to understanding the crater population is to map it. In this work, we describe the steps undertaken to produce a robust crater database of impact features on Pluto, Charon, and their two largest moons, Nix and Hydra. These include an examination of different types of images and image processing, and we present an analysis of variability among the crater mapping team, where crater diameters were found to average ± 10% uncertainty across all sizes measured (∼0.5-300 km). We also present a few basic analyses of the crater databases, finding that Pluto's craters' differential size-frequency distribution across the encounter hemisphere has a power-law slope of approximately -3.1 ± 0.1 over diameters D ≈ 15-200 km, and Charon's has a slope of -3.0 ± 0.2 over diameters D ≈ 10-120 km; it is significantly shallower on both bodies at smaller diameters. We also better quantify evidence of resurfacing evidenced by Pluto's craters in contrast with Charon's. With this work, we are also releasing our database of potential and probable impact craters: 5287 on Pluto, 2287 on Charon, 35 on Nix, and 6 on Hydra.

Craters of the Pluto-Charon System

NASA Technical Reports Server (NTRS)

Robbins, Stuart J.; Singer, Kelsi N.; Bray, Veronica J.; Schenk, Paul; Lauer, Todd R.; Weaver, Harold A.; Runyon, Kirby; Mckinnon, William B.; Beyer, Ross A.; Porter, Simon;

Analysis of the Herschel DEBRIS Sun-like star sample

NASA Astrophysics Data System (ADS)

Sibthorpe, B.; Kennedy, G. M.; Wyatt, M. C.; Lestrade, J.-F.; Greaves, J. S.; Matthews, B. C.; Duchêne, G.

2018-04-01

This paper presents a study of circumstellar debris around Sun-like stars using data from the Herschel DEBRIS Key Programme. DEBRIS is an unbiased survey comprising the nearest ˜90 stars of each spectral type A-M. Analysis of the 275 F-K stars shows that excess emission from a debris disc was detected around 47 stars, giving a detection rate of 17.1^{+2.6}_{-2.3} per cent, with lower rates for later spectral types. For each target a blackbody spectrum was fitted to the dust emission to determine its fractional luminosity and temperature. The derived underlying distribution of fractional luminosity versus blackbody radius in the population showed that most detected discs are concentrated at f ˜ 10-5 and at temperatures corresponding to blackbody radii 7-40 au, which scales to ˜40 au for realistic dust properties (similar to the current Kuiper belt). Two outlying populations are also evident; five stars have exceptionally bright emission ( f > 5 × 10-5), and one has unusually hot dust <4 au. The excess emission distributions at all wavelengths were fitted with a steady-state evolution model, showing that these are compatible with all stars being born with a narrow belt that then undergoes collisional grinding. However, the model cannot explain the hot dust systems - likely originating in transient events - and bright emission systems - arising potentially from atypically massive discs or recent stirring. The emission from the present-day Kuiper belt is predicted to be close to the median of the population, suggesting that half of stars have either depleted their Kuiper belts (similar to the Solar system) or had a lower planetesimal formation efficiency.

SKARPS: The Search for Kuiper Belts around Radial-Velocity Planet Stars

NASA Technical Reports Server (NTRS)

Bryden, Geoffrey; Marshall, Jonathan; Stapelfeldt, Karl; Su, Kate; Wyatt, Mark

2011-01-01

The Search for Kuiper belts Around Radial-velocity Planet Stars - SKARPS -is a Herschel survey of solar-type stars known to have orbiting planets. When complete, the 100-star SKARPS sample will be large enough for a meaningful statistical comparison against stars not known to have planets. (This control sample has already been observed by Herschel's DUst around NEarby Stars - DUNES - key program). Initial results include previously known disks that are resolved for the first time and newly discovered disks that are fainter and colder than those typically detected by Spitzer. So far, with only half of the sample in hand, there is no measured correlation between inner RV planets and cold outer debris. While this is consistent with the results from Spitzer, it is in contrast with the relationship suggested by the prominent debris disks in imaged-planet systems.

Electron Irradiation of Kuiper Belt Surface Ices: Ternary N2-CH4-CO Mixtures as a Case Study

NASA Astrophysics Data System (ADS)

Kim, Y. S.; Kaiser, R. I.

2012-10-01

The space weathering of icy Kuiper Belt Objects was investigated in this case study by exposing methane (CH4) and carbon monoxide (CO) doped nitrogen (N2) ices at 10 K to ionizing radiation in the form of energetic electrons. Online and in situ Fourier transform infrared spectroscopy was utilized to monitor the radiation-induced chemical processing of these ices. Along with isocyanic acid (HNCO), the products could be mainly derived from those formed in irradiated binary ices of the N2-CH4 and CO-CH4 systems: nitrogen-bearing products were found in the form of hydrogen cyanide (HCN), hydrogen isocyanide (HNC), diazomethane (CH2N2), and its radical fragment (HCN2); oxygen-bearing products were of acetaldehyde (CH3CHO), formyl radical (HCO), and formaldehyde (H2CO). As in the pure ices, the methyl radical (CH3) and ethane (C2H6) were also detected, as were carbon dioxide (CO2) and the azide radical (N3). Based on the temporal evolution of the newly formed products, kinetic reaction schemes were then developed to fit the temporal profiles of the newly formed species, resulting in numerical sets of rate constants. The current study highlights important constraints on the preferential formation of isocyanic acid (HNCO) over hydrogen cyanide (HCN) and hydrogen isocyanide (HNC), thus guiding the astrobiological and chemical evolution of those distant bodies.

Sedna Orbit Comparisons

NASA Image and Video Library

2004-03-15

These four panels show the location of the newly discovered planet-like object, dubbed "Sedna," which lies in the farthest reaches of our solar system. Each panel, moving counterclockwise from the upper left, successively zooms out to place Sedna in context. The first panel shows the orbits of the inner planets, including Earth, and the asteroid belt that lies between Mars and Jupiter. In the second panel, Sedna is shown well outside the orbits of the outer planets and the more distant Kuiper Belt objects. Sedna's full orbit is illustrated in the third panel along with the object's current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. The final panel zooms out much farther, showing that even this large elliptical orbit falls inside what was previously thought to be the inner edge of the Oort cloud. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed. http://photojournal.jpl.nasa.gov/catalog/PIA05569

Sedna Orbit Comparisons

NASA Technical Reports Server (NTRS)

2004-01-01

These four panels show the location of the newly discovered planet-like object, dubbed 'Sedna,' which lies in the farthest reaches of our solar system. Each panel, moving counterclockwise from the upper left, successively zooms out to place Sedna in context. The first panel shows the orbits of the inner planets, including Earth, and the asteroid belt that lies between Mars and Jupiter. In the second panel, Sedna is shown well outside the orbits of the outer planets and the more distant Kuiper Belt objects. Sedna's full orbit is illustrated in the third panel along with the object's current location. Sedna is nearing its closest approach to the Sun; its 10,000 year orbit typically takes it to far greater distances. The final panel zooms out much farther, showing that even this large elliptical orbit falls inside what was previously thought to be the inner edge of the Oort cloud. The Oort cloud is a spherical distribution of cold, icy bodies lying at the limits of the Sun's gravitational pull. Sedna's presence suggests that this Oort cloud is much closer than scientists believed.

New Mysteries at Chiron

NASA Technical Reports Server (NTRS)

Elliot, James L.

1998-01-01

Considered as a comet, Chiron is unusual in two respects: (1) it exhibits outbursts at great distances from the sun (nearly up to its aphelion distance of 18.9 AU), and (2) its nucleus is much larger than any other known comet. It is similar in size, however, to the recently discovered Kuiper belt objects, leading to the conjecture that Chiron is closely related to these objects, but its chaotic orbit has brought it much closer to the sun. Our work with the Kuiper Airborne Observatory resulted in the first stellar occultation by Chiron observed simultaneously at visible and infrared wavelengths. We detected four features in the coma, with different degrees of certainty. Our conclusions about Chiron from this work and a previous stellar occultation are: (1) the jet-like features observed provide evidence that the coma material originates from just a few, small active areas, rather than uniform sublimation; (2) a bound coma has possibly been detected; (3) the particle radii in at least one of the jet-like features are larger than 0.25 gm; (4) material in Chiron's orbit plane has likely been detected; and (5) the radius of Chiron's nucleus lies between 83 and 156 km.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinberg, Elad; Sari, Re’em

The Asteroid Belt and the Kuiper Belt are relics from the formation of our solar system. Understanding the size and spin distribution of the two belts is crucial for a deeper understanding of the formation of our solar system and the dynamical processes that govern it. In this paper, we investigate the effect of collisions on the evolution of the spin distribution of asteroids and KBOs. We find that the power law nature of the impactors’ size distribution leads to a Lévy distribution of the spin rates. This results in a power law tail in the spin distribution, in starkmore » contrast to the usually quoted Maxwellian distribution. We show that for bodies larger than 10 km, collisions alone lead to spin rates peaking at 0.15–0.5 revolutions per day. Comparing that to the observed spin rates of large asteroids (R > 50 km), we find that the spins of large asteroids, peaking at ∼1–2 revolutions per day, are dominated by a primordial component that reflects the formation mechanism of the asteroids. Similarly, the Kuiper Belt has undergone virtually no collisional spin evolution, assuming current densities. Collisions contribute a spin rate of ∼0.01 revolutions per day, thus the observed fast spin rates of KBOs are also primordial in nature.« less

Mission Support of the New Horizons 2014 MU69 Encounter via Stellar Occultations

NASA Astrophysics Data System (ADS)

Young, Eliot

The Kuiper belt object 2014 MU69 is the targeted flyby candidate for the New Horizons spacecraft's extended mission, with a close flyby on 1 January 2019. MU69 is thought to be a cold classical Kuiper belt object; it would be the first of these objects to be resolved and studied by a spacecraft. Based on an apparent V-magnitude of 27, the diameter of 2014 MU69 is thought to be between 20 50 km. New Horizons is on track to fly by it on 1-JAN-2019. SOFIA is well-suited to determine or better constrain the size, shape and albedo of this object by observing three bright occultations in 2017. These occultations will also search for dangerous rings (such as those around Chariklo) and provide improved astrometry supporting New Horizons. During the summer of 2017, MU69 will occult stars with V-magnitudes of 15.5, 15.6 and 13.1 on June 3, July 10 and July 17 respectively. Observations with the FPI+ and HIPO photometers at 20 Hz will resolve occultation chord lengths at the few 100-m level, with signal-to-noise ratios of 111.9 and 19.2 per timestep for the 13.1 and 15.5-magnitude stars, respectively. 2014 MU69 would be the smallest known member of the KBO population with a well-known size; as such, its albedo (and the inferred presence or lack of surface frosts) would be a key data point with respect to its impact and accretion history. Knowing the size and albedo 18 months before the New Horizons encounter will be a critical aid in optimizing the flyby observing sequences as well as enabling more precise targeting of the encounter by refining MU69's astrometry and orbit solution. Further, finding rings would constitute an early detection of a significant hazard to the spacecraft.

A disk of scattered icy objects and the origin of Jupiter-family comets.

PubMed

Duncan, M J; Levison, H F

1997-06-13

Orbital integrations carried out for 4 billion years produced a disk of scattered objects beyond the orbit of Neptune. Objects in this disk can be distinguished from Kuiper belt objects by a greater range of eccentricities and inclinations. This disk was formed in the simulations by encounters with Neptune during the early evolution of the outer solar system. After particles first encountered Neptune, the simulations show that about 1 percent of the particles survive in this disk for the age of the solar system. A disk currently containing as few as approximately 6 x 10(8) objects could supply all of the observed Jupiter-family comets. Two recently discovered objects, 1996 RQ20 and 1996 TL66, have orbital elements similar to those predicted for objects in this disk, suggesting that they are thus far the only members of this disk to be identified.

Kuiper belt structure around nearby super-Earth host stars

NASA Astrophysics Data System (ADS)

Kennedy, Grant M.; Matrà, Luca; Marmier, Maxime; Greaves, Jane S.; Wyatt, Mark C.; Bryden, Geoffrey; Holland, Wayne; Lovis, Christophe; Matthews, Brenda C.; Pepe, Francesco; Sibthorpe, Bruce; Udry, Stéphane

2015-05-01

We present new observations of the Kuiper belt analogues around HD 38858 and HD 20794, hosts of super-Earth mass planets within 1 au. As two of the four nearby G-type stars (with HD 69830 and 61 Vir) that form the basis of a possible correlation between low-mass planets and debris disc brightness, these systems are of particular interest. The disc around HD 38858 is well resolved with Herschel and we constrain the disc geometry and radial structure. We also present a probable James Clerk Maxwell Telescope sub-mm continuum detection of the disc and a CO J = 2-1 upper limit. The disc around HD 20794 is much fainter and appears marginally resolved with Herschel, and is constrained to be less extended than the discs around 61 Vir and HD 38858. We also set limits on the radial location of hot dust recently detected around HD 20794 with near-IR interferometry. We present High Accuracy Radial velocity Planet Searcher upper limits on unseen planets in these four systems, ruling out additional super-Earths within a few au, and Saturn-mass planets within 10 au. We consider the disc structure in the three systems with Kuiper belt analogues (HD 69830 has only a warm dust detection), concluding that 61 Vir and HD 38858 have greater radial disc extent than HD 20794. We speculate that the greater width is related to the greater minimum planet masses (10-20 M⊕ versus 3-5 M⊕), arising from an eccentric planetesimal population analogous to the Solar system's scattered disc. We discuss alternative scenarios and possible means to distinguish among them.

Minor Body Surveyor: A Multi-Object, High Speed, Spectro-Photometer Space Mission System Employing Wide-Area Intelligent Change Detection

NASA Astrophysics Data System (ADS)

Kaplan, M. L.; van Cleve, J. E.; Alcock, C.

2003-12-01

Detection and characterization of the small bodies of the outer solar system presents unique challenges to terrestrial based sensing systems, principally the inverse 4th power decrease of reflected and thermal signals with target distance from the Sun. These limits are surpassed by new techniques [1,2,3] employing star-object occultation event sensing, which are capable of detecting sub-kilometer objects in the Kuiper Belt and Oort cloud. This poster will present an instrument and space mission concept based on adaptations of the NASA Discovery Kepler program currently in development at Ball Aerospace and Technologies Corp. Instrument technologies to enable this space science mission are being pursued and will be described. In particular, key attributes of an optimized payload include the ability to provide: 1) Coarse spectral resolution (using an objective spectrometer approach) 2) Wide FOV, simultaneous object monitoring (up to 150,000 stars employing select data regions within a large focal plane mosaic) 3) Fast temporal frame integration and readout architectures (10 to 50 msec for each monitored object) 4) Real-time, intelligent change detection processing (to limit raw data volumes) The Minor Body Surveyor combines the focal plane and processing technology elements into a densely packaged format to support general space mission issues of mass and power consumption, as well as telemetry resources. Mode flexibility is incorporated into the real-time processing elements to allow for either temporal (Occultations) or spatial (Moving targets) change detection. In addition, a basic image capture mode is provided for general pointing and field reference measurements. The overall space mission architecture is described as well. [1] M. E. Bailey. Can 'Invisible' Bodies be Observed in the Solar System. Nature, 259:290-+, January 1976. [2] T. S. Axelrod, C. Alcock, K. H. Cook, and H.-S. Park. A Direct Census of the Oort Cloud with a Robotic Telescope. In ASP Conf. Ser. 34: Robotic Telescopes in the 1990s, pages 171-181, 1992. [3] F. Roques and M. Moncuquet. A Detection Method for Small Kuiper Belt Objects: The Search for Stellar Occultations. Icarus, 147:530-544, October 2000.

The influence of dynamical friction and mean motion resonances on terrestrial planet growth

NASA Astrophysics Data System (ADS)

Wallace, Spencer Clark; Quinn, Thomas R.

2018-04-01

We present a set of high-resolution direct N-body simulations of planetesimal coagulation at 1 AU. We follow the evolution of of 1 million planetesimals in a ring though the runaway and oligarchic growth phases. During oligarchic growth, the size frequency distribution (SFD) of planetesimals develops a bump at intermediate masses, which we argue is due to dynamical friction acting through mean motion resonances, heating the low mass planetesimals and inhibiting their growth. This feature is similar to the bump seen in the SFD of asteroid belt and Kuiper belt objects and we argue that a careful treatment of the dynamics of planetesimal interactions is required in order to adequately explain the observed SFD. Although our model does not account for fragmentation, our results show that a similar feature can be produced without it, which is in contention with previous studies.

Super-Earth at a distance of less than 1,000 AU in solar system is absent

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.

2017-12-01

Numerous observations have shown that the Kuiper belt is a dynamically stable system. The source of cometary nuclei can be a scattered disk. It is an area created by outward-directed gravitational perturbations of the outer giant planets more than 4 billion years ago. The objects of the scattered disk are similar to the bodies of the Kuiper belt. But they go in their orbits for distances up to several hundred astronomical units (AU). In 2016 Brown and Batygin reported about indirect evidence of the existence of so far unknown ninth planet in the Solar system. They suggested, that orbits of 6 known trans-Neptunian objects of scattered disk are oriented so, that they can be influenced by a large, yet unknown body. We draw attention to the fact, that these 6 objects in close to their discovering moments were located at perihelion. We assume that for many orders of magnitude a larger number of the same trans-Neptunian objects should be located at a greater distance from the perihelion. Therefore, a possible number of the same trans-Neptunian objects should be counted in many thousands. We used the observation data obtained by Space Telescope "WISE" (Wide-Field Infrared Survey Explorer). It was established that there is no analogue of the giant planet Saturn at distances up to 30000 AU. This circumstance allowed us to calculate that at distances up to 1000 AU it would be clearly visible planetary body with a radius of more than 11000 km. That is, a planet with a possible mass of about 10 Earth masses and an "earth" density (5.52 t/m3). If we take into account that the density of the "average" trans-Neptunian object differs little from 2 t/m3, the radius of such a body will increase to 19200 km. And then the limit of detection of the body will increase by almost 4 times: up to 4000 AU. (!) Thus, either unknown 9th planet is now even further, or our results cannot be directly scaled for the planet "Super-Earth", which at such large distance can have a disproportionately low source of internal heat.

Environmental Impact Specification for Direct Space Weathering of Kuiper Belt and Oort Cloud Objects

NASA Technical Reports Server (NTRS)

Cooper, John F.

2010-01-01

The Direct Space Weathering Project of NASA's Outer Planets Research Program addresses specification of the plasma and energetic particle environments for irradiation and surface chemical processing of icy bodies in the outer solar system and the local interstellar medium. Knowledge of the radiation environments is being expanded by ongoing penetration of the twin Voyager spacecraft into the heliosheath boundary region of the outer heliosphere and expected emergence within the next decade into the very local interstellar medium. The Voyager measurements are being supplemented by remote sensing from Earth orbit of energetic neutral atom emission from this boundary region by NASA's Interstellar Boundary Explorer (IBEX). Although the Voyagers long ago passed the region of the Classical Kuiper Belt, the New Horizons spacecraft will encounter Pluto in 2015 and thereafter explore one or more KBOs, meanwhile providing updated measurements of the heliospheric radiation environment in this region. Modeling of ion transport within the heliosphere allows specification of time-integrated irradiation effects while the combination of Voyager and IBEX data supports projection of the in-situ measurements into interstellar space beyond the heliosheath. Transformation of model ion flux distributions into surface sputtering and volume ionization profiles provides a multi-layer perspective for space weathering impact on the affected icy bodies and may account for some aspects of color and compositional diversity. Other important related factors may include surface erosion and gardening by meteoritic impacts and surface renewal by cryovolcanism. Chemical products of space weathering may contribute to energy resources for the latter.

Trajectories for a Near Term Mission to the Interstellar Medium

NASA Technical Reports Server (NTRS)

Arora, Nitin; Strange, Nathan; Alkalai, Leon

2015-01-01

Trajectories for rapid access to the interstellar medium (ISM) with a Kuiper Belt Object (KBO) flyby, launching between 2022 and 2030, are described. An impulsive-patched-conic broad search algorithm combined with a local optimizer is used for the trajectory computations. Two classes of trajectories, (1) with a powered Jupiter flyby and (2) with a perihelion maneuver, are studied and compared. Planetary flybys combined with leveraging maneuvers reduce launch C3 requirements (by factor of 2 or more) and help satisfy mission-phasing constraints. Low launch C3 combined with leveraging and a perihelion maneuver is found to be enabling for a near-term potential mission to the ISM.

The Complex History of Trojan Asteroids

NASA Astrophysics Data System (ADS)

Emery, J. P.; Marzari, F.; Morbidelli, A.; French, L. M.; Grav, T.

The Trojan asteroids, orbiting the Sun in Jupiter's stable Lagrange points, provide a unique perspective on the history of our solar system. As a large population of small bodies, they record important gravitational interactions in the dynamical evolution of the solar system. As primitive bodies, their compositions and physical properties provide windows into the conditions in the solar nebula in the region in which they formed. In the past decade, significant advances have been made in understanding their physical properties, and there has been a revolution in thinking about the origin of Trojans. The ice and organics generally presumed to be a significant part of Trojan composition have yet to be detected directly, although the low density of the binary system Patroclus (and possibly low density of the binary/moonlet system Hektor) is consistent with an interior ice component. By contrast, fine-grained silicates that appear to be similar to cometary silicates in composition have been detected, and a color bimodality may indicate distinct compositional groups among the Trojans. Whereas Trojans had traditionally been thought to have formed near 5 AU, a new paradigm has developed in which the Trojans formed in the proto-Kuiper belt, and were scattered inward and captured in the Trojan swarms as a result of resonant interactions of the giant planets. Whereas the orbital and population distributions of current Trojans are consistent with this origin scenario, there are significant differences between current physical properties of Trojans and those of Kuiper belt objects. These differences may be indicative of surface modification due to the inward migration of objects that became the Trojans, but understanding of appropriate modification mechanisms is poor and would benefit from additional laboratory studies. Many open questions about this intriguing population remain, and the future promises significant strides in our understanding of Trojans. The time is ripe for a spacecraft mission to the Trojans, to transform these objects into geologic worlds that can be studied in detail to unravel their complex history.

Compositional Remote Sensing of Icy Planets and Satellites Beyond Jupiter

NASA Technical Reports Server (NTRS)

Roush, T. L.

2002-01-01

The peak of the solar energy distribution occurs at visual wavelengths and falls off rapidly in the infrared. This fact, improvements in infrared detector technology, and the low surface temperatures for most icy objects in the outer solar system have resulted in the bulk of telescopic and spacecraft observations being performed at visual and near-infrared wavelengths. Such observations, begun in the early 1970's and continuing to present, have provided compositional information regarding the surfaces of the satellites of Saturn and Uranus, Neptune's moon Triton, Pluto, Pluto's moon Charon, Centaur objects, and Kuiper belt objects. Because the incident sunlight penetrates the surface and interacts with the materials present there, the measured reflected sunlight contains information regarding the surface materials, and the ratio of the reflected to incident sunlight provides a mechanism of identifying the materials that are present.

MEASURING THE ABUNDANCE OF SUB-KILOMETER-SIZED KUIPER BELT OBJECTS USING STELLAR OCCULTATIONS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schlichting, Hilke E.; Ofek, Eran O.; Gal-Yam, Avishay

2012-12-20

We present here the analysis of about 19,500 new star hours of low ecliptic latitude observations (|b| {<=} 20 Degree-Sign ) obtained by the Hubble Space Telescope's Fine Guidance Sensors over a time span of more than nine years, which is in addition to the {approx}12, 000 star hours previously analyzed by Schlichting et al. Our search for stellar occultations by small Kuiper Belt Objects (KBOs) yielded one new candidate event corresponding to a body with a 530 {+-} 70 m radius at a distance of about 40 AU. Using bootstrap simulations, we estimate a probability of Almost-Equal-To 5% thatmore » this event is due to random statistical fluctuations within the new data set. Combining this new event with the single KBO occultation reported by Schlichting et al. we arrive at the following results: (1) the ecliptic latitudes of 6. Degree-Sign 6 and 14. Degree-Sign 4 of the two events are consistent with the observed inclination distribution of larger, 100-km-sized KBOs. (2) Assuming that small, sub-kilometer-sized KBOs have the same ecliptic latitude distribution as their larger counterparts, we find an ecliptic surface density of KBOs with radii larger than 250 m of N(r > 250 m) = 1.1{sup +1.5}{sub -0.7} Multiplication-Sign 10{sup 7} deg{sup -2}; if sub-kilometer-sized KBOs have instead a uniform ecliptic latitude distribution for -20 Degree-Sign < b < 20 Degree-Sign then N(r > 250 m) = 4.4{sup +5.8}{sub -2.8} Multiplication-Sign 10{sup 6} deg{sup -2}. This is the best measurement of the surface density of sub-kilometer-sized KBOs to date. (3) Assuming the KBO size distribution can be well described by a single power law given by N(> r){proportional_to}r{sup 1-q}, where N(> r) is the number of KBOs with radii greater than r, and q is the power-law index, we find q = 3.8 {+-} 0.2 and q = 3.6 {+-} 0.2 for a KBO ecliptic latitude distribution that follows the observed distribution for larger, 100-km-sized KBOs and a uniform KBO ecliptic latitude distribution for -20 Degree-Sign < b < 20 Degree-Sign , respectively. (4) Regardless of the exact power law, our results suggest that small KBOs are numerous enough to satisfy the required supply rate for the Jupiter family comets. (5) We can rule out a single power law below the break with q > 4.0 at 2{sigma}, confirming a strong deficit of sub-kilometer-sized KBOs compared to a population extrapolated from objects with r > 45 km. This suggests that small KBOs are undergoing collisional erosion and that the Kuiper Belt is a true analog to the dust producing debris disks observed around other stars.« less

Properties of resonant trans-Neptunian objects based on Herschel Space Observatory data

NASA Astrophysics Data System (ADS)

Farkas Anikó, Takácsné; Kiss, Csaba; Mueller, Thomas G.; Mommert, Michael; Vilenius, Esa

2016-10-01

The goal of our work is to characterise the physical characteristics of resonant, detached and scattered disk objects in the trans-Neptunian region, observed in the framework of the "TNOs are Cool!" Herschel Open Time Key Program. Based on thermal emission measurements with the Herschel/PACS and Spitzer/MIPS instruments we were able to determine size, albedo, and surface thermal properties for 23 objects using radiometric modelling techniques. This is the first analysis in which the physical properties of objects in the outer resonances are determined for a larger sample. In addition to the results for individual objects, we have compared these characteristic with the bulk properties of other populations of the trans-Neptunian region. The newly analysed objects show e.g. a large variety of beaming factors, indicating diverse surfaces, and in general they follow the albedo-colour clustering identified earlier for Kuiper belt objects and Centaurs, further strengthening the evidence for a compositional discontinuity in the young solar system.

Discovery and characteristics of the rapidly rotating active asteroid (62412) 2000 SY178 in the main belt

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheppard, Scott S.; Trujillo, Chadwick, E-mail: ssheppard@carnegiescience.edu

We report a new active asteroid in the main belt of asteroids between Mars and Jupiter. Object (62412) 2000 SY178 exhibited a tail in images collected during our survey for objects beyond the Kuiper Belt using the Dark Energy Camera on the CTIO 4 m telescope. We obtained broadband colors of 62412 at the Magellan Telescope, which, along with 62412's low albedo, suggests it is a C-type asteroid. 62412's orbital dynamics and color strongly correlate with the Hygiea family in the outer main belt, making it the first active asteroid known in this heavily populated family. We also find 62412more » to have a very short rotation period of 3.33 ± 0.01 hours from a double-peaked light curve with a maximum peak-to-peak amplitude of 0.45 ± 0.01 mag. We identify 62412 as the fastest known rotator of the Hygiea family and the nearby Themis family of similar composition, which contains several known main belt comets. The activity on 62412 was seen over one year after perihelion passage in its 5.6 year orbit. 62412 has the highest perihelion and one of the most circular orbits known for any active asteroid. The observed activity is probably linked to 62412's rapid rotation, which is near the critical period for break-up. The fast spin rate may also change the shape and shift material around 62412's surface, possibly exposing buried ice. Assuming 62412 is a strengthless rubble pile, we find the density of 62412 to be around 1500 kg m{sup −3}.« less

Heliospheric and Local Interstellar Space Weathering Environments of Extreme Kuiper Belt Objects

NASA Astrophysics Data System (ADS)

Cooper, J. F.; Sturner, S. J.

2017-12-01

Since the first direct detection of a Kuiper Belt Object (KBO), (15760) 1992 QB1, in 1992, observational evidence via direct detection has accumulated for thousands (and via inference for hundreds of thousands) of small to large icy bodies that populate the solar system from within the supersonic heliosphere out into the local interstellar medium (LISM). These objects have mainly been discovered when within the heliosphere but the orbits of the more extreme KBOs, fifteen percent of the total known KBO population, take them out into the heliosheath and about half of these continue further out into the LISM. Continuing observations will inevitably increase the known inventory of extreme KBOs, possibly including a few that may be accessible as near-encounter targets for a future interstellar probe mission directed beyond 200 AU into the upstream LISM. Here we review the known population of extreme KBOs and address the properties of the heliospheric and LISM environments that could potentially affect object visibility and surface composition. The twin Voyager spacecraft are our present source of in-situ measurements for the plasma and energetic particle environments, except that there are no plasma data from Voyager 1. Voyager 1 and 2 are now respectively in the LISM and the heliosheath after earlier passing through the outer regions of the supersonic heliosphere upstream of the solar wind termination shock. The Voyager data coverage is complemented by energetic neutral atom (ENA) measurements of the Interstellar Background Explorer (IBEX) and Cassini Orbiter spacecraft that can be used to infer proton flux spectra from models of ENA production in the outer heliosphere. High radiation background in the LISM has precluded sub-MeV energetic ion measurements by Voyager 1, so we use limits from Cummings et al. (ApJ, 2016) for molecular cloud ionization. This would be an important energy region to cover with interstellar probe measurements. These sources of plasma and energetic particle flux measurements are used to estimate values for space weathering parameters including surface energy flux and pressure, dosage vs. depth profiles for chemical processing of mixed ice surfaces, and ion sputtering rates. We further consider other space weathering processes including ultraviolet irradiation and meteoritic impact gardening.

Solar system science with ESA Euclid

NASA Astrophysics Data System (ADS)

Carry, B.

2018-01-01

Context. The ESA Euclid mission has been designed to map the geometry of the dark Universe. Scheduled for launch in 2020, it will conduct a six-year visible and near-infrared imaging and spectroscopic survey over 15 000 deg2 down to VAB 24.5. Although the survey will avoid ecliptic latitudes below 15°, the survey pattern in repeated sequences of four broadband filters seems well-adapted to detect and characterize solar system objects (SSOs). Aims: We aim at evaluating the capability of Euclid of discovering SSOs and of measuring their position, apparent magnitude, and spectral energy distribution. We also investigate how the SSO orbits, morphology (activity and multiplicity), physical properties (rotation period, spin orientation, and 3D shape), and surface composition can be determined based on these measurements. Methods: We used the current census of SSOs to extrapolate the total amount of SSOs that will be detectable by Euclid, that is, objects within the survey area and brighter than the limiting magnitude. For each different population of SSO, from neighboring near-Earth asteroids to distant Kuiper-belt objects (KBOs) and including comets, we compared the expected Euclid astrometry, photometry, and spectroscopy with the SSO properties to estimate how Euclid will constrain the SSOs dynamical, physical, and compositional properties. Results: With the current survey design, about 150 000 SSOs, mainly from the asteroid main-belt, should be observable by Euclid. These objects will all have high inclination, which is a difference to many SSO surveys that focus on the ecliptic plane. Euclid may be able to discover several 104 SSOs, in particular, distant KBOs at high declination. The Euclid observations will consist of a suite of four sequences of four measurements and will refine the spectral classification of SSOs by extending the spectral coverage provided by Gaia and the LSST, for instance, to 2 microns. Combined with sparse photometry such as measured by Gaia and the LSST, the time-resolved photometry will contribute to determining the SSO rotation period, spin orientation, and 3D shape model. The sharp and stable point-spread function of Euclid will also allow us to resolve binary systems in the Kuiper belt and detect activity around Centaurs. Conclusions: The depth of the Euclid survey (VAB 24.5), its spectral coverage (0.5 to 2.0 μm), and its observation cadence has great potential for solar system research. A dedicated processing for SSOs is being set up within the Euclid consortium to produce astrometry catalogs, multicolor and time-resolved photometry, and spectral classification of some 105 SSOs, which will be delivered as Legacy Science.

Impact and cratering rates onto Pluto

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Gladman, Brett; McKinnon, William B.

2015-09-01

The New Horizons spacecraft fly-through of the Pluto system in July 2015 will provide humanity's first data for the crater populations on Pluto and its binary companion, Charon. In principle, these surfaces could be dated in an absolute sense, using the observed surface crater density (# craters/km2 larger than some threshold crater diameter D). Success, however, requires an understanding of both the cratering physics and absolute impactor flux. The Canada-France Ecliptic Plane Survey (CFEPS) L7 synthetic model of classical and resonant Kuiper belt populations (Petit, J.M. et al. [2011]. Astron. J. 142, 131-155; Gladman, B. et al. [2012]. Astron. J. 144, 23-47) and the scattering object model of Kaib et al. (Kaib, N., Roškar, R., Quinn, T. [2011]. Icarus 215, 491-507) calibrated by Shankman et al. (Shankman, C. et al. [2013]. Astrophys. J. 764, L2-L5) provide such impact fluxes and thus current primary cratering rates for each dynamical sub-population. We find that four sub-populations (the q < 42AU hot and stirred main classicals, the classical outers, and the plutinos) dominate Pluto's impact flux, each providing ≈ 15- 25 % of the total rate. Due to the uncertainty in how the well-characterized size distribution for Kuiper belt objects (with impactor diameter d > 100km) connects to smaller projectiles, we compute cratering rates using five model impactor size distributions: a single power-law, a power-law with a knee, a power-law with a divot, as well as the "wavy" size distributions described in Minton et al. (Minton, D.A. et al. [2012]. Asteroids Comets Meteors Conf. 1667, 6348) and Schlichting et al. (Schlichting, H.E., Fuentes, C.I., Trilling, D.E. [2013]. Astron. J. 146, 36-42). We find that there is only a small chance that Pluto has been hit in the past 4 Gyr by even one impactor with a diameter larger than the known break in the projectile size distribution (d ≈ 100km) which would create a basin on Pluto (D ⩾ 400km in diameter). We show that due to present uncertainties in the impactor size distribution between d = 1- 100km , computing absolute ages for the surface of Pluto is entirely dependent on the extrapolation to small sizes and thus fraught with uncertainty. We show, however, what the ages would be for several cases and illustrate the relative importance of each Kuiper belt sub-population to the cratering rate, both now and integrated into the past. In addition, we compute the largest "fresh" crater expected to have formed in 1 Gyr on the surface of Pluto and in 3 Gyr on Charon (to 95% confidence) and use the "wavy" size distribution models to predict whether these largest "fresh" craters will provide surfaces for which portions of the crater production function can be measured should most of the target's surface appear saturated. The fly-through results coupled with telescopic surveys that bridge current uncertainties in the d = 10- 100km regime should eventually result in the population estimate uncertainties for the Kuiper belt sub-populations, and thus the impact fluxes onto Pluto and Charon, dipping to < 30 % . We also compute "disruption timescales" (to a factor of three accuracy) for Pluto's smaller satellites: Styx, Nix, Kerberos, and Hydra. We find that none of the four satellites have likely undergone a catastrophic disruption and reassembly event in the past ≈ 4Gyr . In addition, we find that for a knee size distribution with αfaint ⩽ 0.4 (down to sub-km diameters), satellites of all sizes are able to survive catastrophic disruption over the past 4 Gyr.

Sources of Terrestrial Volatiles

NASA Technical Reports Server (NTRS)

Zahnle, K. J.; Dones, L.

1998-01-01

Atmospheres are found enveloping those planets and satellites best able to hold them. The obvious conclusion is that volatile escape must have played nearly as great a role as volatile supply. A consequence of this view is that volatile supplies were probably much greater than the atmospheres that remain. The likeliest candidates are sources associated with the main events of planetary accretion itself such as volatile-rich planetesimals, or direct gravitational capture of nebular gases. Late asteroidal or cometary volatile-rich veneers are attractive, but they present quantitative difficulties. Comets in particular are inadequate, because the associated mass of stray comets that would have been scattered to the Oort Cloud or beyond is excessive. This difficulty applies to Uranus-Neptune planetesimals as well as to a putative massive early Kuiper Belt. Another potential problem with comets is that the D/H ratio in the three comets for which this has been measured is about twice that of Earth's oceans. Objects falling from a much augmented ancient asteroid belt remain a viable option, but timing is an issue: Can the depopulation of the asteroid belt be delayed long enough that it makes sense to talk of asteroids as a late veneer? Early accretion of asteroids as objects scattered into the maw of infant Earth makes more sense. Another appealing candidate population of volatile-rich objects for the inner solar system would be scattered planetesimals associated with the accretion of Jupiter, for two reasons: (1) Before there was Jupiter, there was no object in the solar system capable of expelling comets efficiently, and (2) the cross section of the inner solar system to stray objects was Greater when there were m many planetesimals.

Spectral Models of Kuiper Belt Objects and Centaurs

NASA Technical Reports Server (NTRS)

Cruikshank, Dale; Ore, Christina M. Dalle

2003-01-01

We present models of the spectral reflectances of groups of outer Solar System objects defined primarily by their colors in the spectral region 0.4 -1.2 microns, and which have geometric albedo 0.04 at wavelength 0.55 microns. Our models of the groups with the strongest reflectance gradients (reddest colors) use combinations of organic tholins. We test the hypothesis that metal-reddened igneous rock-forming minerals contribute to the red colors of Centaurs and KBOs by using the space-weathered lunar soil as one of the components of our models. We find that our models can admit the presence of moderate amounts of space-weathered (metal-reddened) minerals, but that they do not require this material to achieve the red colors of the reddest outer Solar System bodies. Our models with organic tholins are consistent with the results of other investigators.

The Performance of Ultra-stable Oscillators for the Gravity Recovery and Interior Laboratory (GRAIL)

DTIC Science & Technology

2010-11-01

the mid-2000s for JHU/APL’s exploration mission of Pluto and the Kuiper belt . Fig. 1. Timeline of USO mission legacy with history of...determination at remote bodies far from Earth extends the possibility of measuring other moons, planets, and asteroids in future science mission concepts

DUst around NEarby Stars. The Survey Observational Results

NASA Technical Reports Server (NTRS)

Eiroa, C.; Marshall, J. P.; Mora, A.; Montesinos, B.; Absil, O.; Augereau, J. Ch.; Bayo, A.; Bryden, G.; Danchi, W.; delBurgo, C.;

Dumb-bell-shaped equilibrium figures for fiducial contact-binary asteroids and EKBOs

NASA Astrophysics Data System (ADS)

Descamps, Pascal

2015-01-01

In this work, we investigate the equilibrium figures of a dumb-bell-shaped sequence with which we are still not well acquainted. Studies have shown that these elongated and nonconvex figures may realistically replace the classic “Roche binary approximation” for modeling putative peanut-shaped or contact binary asteroids. The best-fit dumb-bell shapes, combined with the known rotational period of the objects, provide estimates of the bulk density of these objects. This new class of mathematical figures has been successfully tested on the observed light curves of three noteworthy small bodies: main-belt Asteroid 216 Kleopatra, Trojan Asteroid 624 Hektor and Edgeworth-Kuiper-belt object 2001 QG298. Using the direct observations of Kleopatra and Hektor obtained with high spatial resolution techniques and fitting the size of the dumb-bell-shaped solutions, we derived new physical characteristics in terms of equivalent radius, 62.5 ± 5 km and 92 ± 5 km, respectively, and bulk density, 4.4 ± 0.4 g cm-3 and 2.43 ± 0.35 g cm-3, respectively. In particular, the growing inadequacy of the radar shape model for interpreting any type of observations of Kleopatra (light curves, AO images, stellar occultations) in a satisfactory manner suggests that Kleopatra is more likely to be a dumb-bell-shaped object than a “dog-bone.”

The contraction/expansion history of Charon with implications for its planetary-scale tectonic belt

NASA Astrophysics Data System (ADS)

Malamud, Uri; Perets, Hagai B.; Schubert, Gerald

2017-06-01

The New Horizons mission to the Kuiper belt has recently revealed intriguing features on the surface of Charon, including a network of chasmata, cutting across or around a series of high topography features, conjoining to form a belt. It is proposed that this tectonic belt is a consequence of contraction/expansion episodes in the moon's evolution associated particularly with compaction, differentiation and geochemical reactions of the interior. The proposed scenario involves no need for solidification of a vast subsurface ocean and/or a warm initial state. This scenario is based on a new, detailed thermo-physical evolution model of Charon that includes multiple processes. According to the model, Charon experiences two contraction/expansion episodes in its history that may provide the proper environment for the formation of the tectonic belt. This outcome remains qualitatively the same, for several different initial conditions and parameter variations. The precise orientation of Charon's tectonic belt, and the cryovolcanic features observed south of the tectonic belt may have involved a planetary-scale impact, that occurred only after the belt had already formed.

The Dynamics of Objects in the Inner Edgeworth Kuiper Belt

NASA Astrophysics Data System (ADS)

Jones, Daniel C.; Williams, Iwan P.; Melita, Mario D.

2005-12-01

Objects in 3:2 mean motion resonance with Neptune are protected from close encounters with Neptune by the resonance. Bodies in orbits with semi-major axis between 39.5 and about 42 AU are not protected by the resonance; indeed due to overlapping secular resonances, the eccentricities of orbits in this region are driven up so that a close encounter with Neptune becomes inevitable. It is thus expected that such orbits are unstable. The list of known Trans-Neptunian objects shows a deficiency in the number of objects in this gap compared to the 43 50 AU region, but the gap is not empty. We numerically integrate models for the initial population in the gap, and also all known objects over the age of the Solar System to determine what fraction can survive. We find that this fraction is significantly less than the ratio of the population in the gap to that in the main belt, suggesting that some mechanism must exist to introduce new members into the gap. By looking at the evolution of the test body orbits, we also determine the manner in which they are lost. Though all have close encounters with Neptune, in most cases this does not lead to ejection from the Solar System, but rather to a reduced perihelion distance causing close encounters with some or all of the other giant planets before being eventually lost from the system, with Saturn appearing to be the cause of the ejection of most of the objects.

Debiasing the Distant Solar System Populations Using Pan-STARRS1

NASA Astrophysics Data System (ADS)

Lilly Schunova, Eva; Weryk, Robert J.; Chastel, Serge; Denneau, Larry; Jedicke, Robert; Wainscoat, Richard J.; Chambers, Kenneth C.

2017-10-01

We discuss our on-going effort to identify Trans-Neptunian Objects (TNOs) in the Pan-STARRS1 dataset, and to debias the size-frequency distributions (SFD) of detected TNO sub-populations in order to estimate their true population sizes. To measure our detection efficiency we used the model of Grav et al. (2011)[1], which includes Kuiper belt Objects (KBOs), Scattered Disc Objects (SDOs), and Centaurs. Our debiasing method accounts for the per-chip CCD sensitivity as well as CCD cell gaps. The search method for finding distant Solar System objects, which was developed for our initial work (Weryk et al., 2016)[2], led to discovery of 29 Centaurs, 243 KBOs and 61 SDOs from Pan-STARRS data spanning years 2010-2015. Our work is extended using more recent PS1 data.[1] Grav, T., et al. (2011), Publications of the Astronomical Society of Pacific, Volume 123, Issue 902, pp. 423.[2] Weryk, R.J., et al. (2016), eprint arXiv:1607.04895.

SAFARI: Searching Asteroids For Activity Revealing Indicators

NASA Astrophysics Data System (ADS)

Curtis, Anthony; Chandler, Colin Orion; Mommert, Michael; Sheppard, Scott; Trujillo, Chadwick A.

2018-06-01

We present results on one of the deepest and widest systematic searches for active asteroids, objects in the main-belt which behave dynamically like asteroids but display comet-like comae. This activity comes from a variety of sources, such as the sublimation of ices or rotational breakup, the former of which offers an opportunity to study a family of protoplanetary ices different than those seen in comets and Kuiper Belt objects. Indications of activity may be detected through visual or spectroscopic evidence of gas or dust emissions. However, these objects are still poorly understood, with only about 25 identified to date. We looked for activity indicators with a pipeline that examined ~35,000 deep images taken with the Dark Energy Camera (DECam) mounted on the 4-meter Blanco telescope at the Cerro Tololo Inter-American Observatory in Chile. Our pipeline was configured to perform astrometry on DECam images and produce thumbnail images of known asteroids in the field to be examined by eye for signs of activity. We detected three previously identified active asteroids, one of which has shown repeated signs of activity in these data. Our proof of concept demonstrates 1) our novel informatics approach can locate active asteroids 2) DECam data are well suited to search for active asteroids. We will discuss the design structure of our pipeline, adjustments that had to be made for the specific dataset to improve performance, and the the significance of detecting activity in the main-belt. The authors acknowledge funding for this project through NSF grant number AST-1461200.

Student Dust Counter I : Science Objectives

NASA Astrophysics Data System (ADS)

Mitchell, C.; Bryant, C.; Bunch, N.; Chanthawanich, T.; Colgan, M.; Fernandez, A.; Grogan, B.; Holland, G.; Krauss, C.; Krauss, E.; Krauss, O.; Neeland, M.; Horanyi, M.

2003-12-01

The New Horizons mission to Pluto and the Kuiper Belt is scheduled for launch in January 2006. As part of the Education and Public Outreach activity of the mission, undergraduate and graduate students at the Laboratory for Atmospheric and Space Physics, University of Colorado, are building a space experiment: the Student Dust Counter (SDC). This talk will summarize the scientific goals of this experiment. An accompanying poster describes the technical details of SDC. The primary goal of SDC is to map the dust distribution in the Solar System from 1 to 50 AU. It will greatly enhance our knowledge of dust production and transport in the outer Solar System by providing more sensitive observations than earlier experiments past Saturn, and the first in situ dust observations beyond 18 AU.

The Surface Age of Sputnik Planum, Pluto, Must Be Less than 10 Million Years.

PubMed

Trilling, David E

2016-01-01

Data from the New Horizons mission to Pluto show no craters on Sputnik Planum down to the detection limit (2 km for low resolution data, 625 m for high resolution data). The number of small Kuiper Belt Objects that should be impacting Pluto is known to some degree from various astronomical surveys. We combine these geological and telescopic observations to make an order of magnitude estimate that the surface age of Sputnik Planum must be less than 10 million years. This maximum surface age is surprisingly young and implies that this area of Pluto must be undergoing active resurfacing, presumably through some cryo-geophysical process. We discuss three possible resurfacing mechanisms and the implications of each one for Pluto's physical properties.

Evolution of the Edgeworth-Kuiper Belt and Kuiperoidal Dust

NASA Astrophysics Data System (ADS)

Ozernoy, L. M.; Ipatov, S. I.

Evolution of orbits of Edgeworth-Kuiper belt objects (EKBOs) under the gravitational influence of the giant planets has been studied by a number of authors (e.g., Duncan & Levison; Budd; Ozernoy, Gorkavyi & Taidakova). Here we show that the gravitational interactions of EKBOs can also play a certain role in their orbital evolution. For instance, during the last 4 Gyr as many as several percents of EKBOs could change their semimajor axes by more than 1 AU due to close encounters with other EKBOs. Even small variations in orbital elements of EKBOs caused by their mutual collisions coupled with the mutual gravitational influence can cause large variations in the orbital elements due to the gravitational influence of planets. About 6% of Neptune-crossers can reach the orbit of the Earth, with the average time in Earth-crossing orbits of about 5× 103 yr. The portion of former EKBOs now moving in Earth-crossing orbits can exceed 20% of all Earth-crossers. Evaporation of the volatile material from the EKBOs surfaces, due to mutual EKBO collisions, along with the Solar wind and the heating by the Sun, are the sources of the dust in the outer Solar system. The evolution and structure of the interplanetary dust cloud computed, in some approximations, by Gorkavyi, Ozernoy, Mather, & Taidakova offers a preliminary 3-D physical model of the cloud, which includes three dust components (asteroidal, cometary, and kuiperoidal), which is fairly consistent with the available data of Pioneer and Voyager dust detectors and contribution of the zodiacal light into the COBE/DIRBE data. We acknowledge support of this work by NASA grant NAG5-10776, the Russian Federal Program ``Astronomy'' (section 1.9.4.1), RFBR (01-02-17540), and INTAS (00-240).

Detection technique for artificially illuminated objects in the outer solar system and beyond.

PubMed

Loeb, Abraham; Turner, Edwin L

2012-04-01

Existing and planned optical telescopes and surveys can detect artificially illuminated objects, comparable in total brightness to a major terrestrial city, at the outskirts of the Solar System. Orbital parameters of Kuiper belt objects (KBOs) are routinely measured to exquisite precisions of<10(-3). Here, we propose to measure the variation of the observed flux F from such objects as a function of their changing orbital distances D. Sunlight-illuminated objects will show a logarithmic slope α ≡ (d log F/d log D)=-4, whereas artificially illuminated objects should exhibit α=-2. The proposed Large Synoptic Survey Telescope (LSST) and other planned surveys will provide superb data and allow measurement of α for thousands of KBOs. If objects with α=-2 are found, follow-up observations could measure their spectra to determine whether they are illuminated by artificial lighting. The search can be extended beyond the Solar System with future generations of telescopes on the ground and in space that would have the capacity to detect phase modulation due to very strong artificial illumination on the nightside of planets as they orbit their parent stars.

Patrick Moore's Data Book of Astronomy

NASA Astrophysics Data System (ADS)

Moore, Patrick; Rees, Robin

2014-01-01

1. The Solar System; 2. The Sun; 3. The Moon; 4. Mercury; 5. Venus; 6. Earth; 7. Mars; 8. The asteroid belt; 9. Jupiter; 10. Saturn; 11. Uranus; 12. Neptune; 13. Beyond Neptune: the Kuiper Belt; 14. Comets; 15. Meteors; 16. Meteorites; 17. Glows and atmospheric effects; 18. The stars; 19. Stellar spectra and evolution; 20. Extrasolar planets; 21. Double stars; 22. Variable stars; 23. Stellar clusters; 24. Nebulae; 25. The Galaxy; 26. The evolution of the Universe; 27. The constellations; 28. The star catalogue; 29. Telescopes and observatories; 30. Non-optical astronomy; 31. The history of astronomy; 32. Astronomers; 33. Glossary; Index.

HUBBLE HUNTS DOWN BINARY OBJECTS AT FRINGE OF OUR SOLAR SYSTEM

NASA Technical Reports Server (NTRS)

2002-01-01

NASA's Hubble Space Telescope snapped pictures of a double system of icy bodies in the Kuiper Belt. This composite picture shows the apparent orbit of one member of the pair. In reality, the objects, called 1998 WW31, revolve around a common center of gravity, like a pair of waltzing skaters. This picture shows the motion of one member of the duo [the six faint blobs] relative to the other [the large white blob]. The blue oval represents the orbital path. Astronomers assembled this picture from six separate exposures, taken from July to September 2001, December 2001, and January to February 2002. Astronomers used the Hubble telescope to study the orbit of this binary system. They then used that information to determine other characteristics of the duo, such as their total mass, and their orbital period (the time it takes them to orbit each other). Credit: NASA and C. Veillet (Canada-France-Hawaii Telescope)

Search for Planetary-mass Companions of the LHB Star eta Corvi

NASA Astrophysics Data System (ADS)

Marengo, Massimo; Lisse, Carey; Stapelfeldt, Karl; Hulsebus, Alan; Sitko, Michael

2016-08-01

The nearby sun-like star eta Corvi (F2V, d = 18 pc, age = 1.2 Gyr) has long been known to possess a bright, dusty Kuiper belt that has been recently resolved with Herschel/PACS. In addition to this structure, eta Corvi is one of the rare mature planetary systems to possess also an inner warm belt (~ 3 AU radius), located within the Terrestrial Habitable Zone (TLZ) of this star. Our characterization of this structure, based on Spitzer/IRS and NASA/IRTF SpeX spectral observations, reveals the signature of ice, organics and silicate dust in this warm belt. This supports the hypothesis that eta Corvi is undergoing a Late Heavy Bombardment (LHB), delivering life-bearing water- and organic-rich material from the Kuiper belt to the TLZ, at roughly the same age as the Solar System?s LHB. For the past four years we have monitored the brightness of eta Corvi?s warm belt with Spitzer/IRAC, finding that its infrared emission has been stable over a multi-year timescale. In 2012 we have also conducted a search for widely separated substellar-mass companions of this star, whose presence as been suggested as a possible trigger for the LHB currently undergoing in the system. This search has led to the identification of three sources with colors and magnitudes consistent with being late-T and Y dwarf companions of this star. We here propose to acquire a new deep roll-subtracted image of the system, 5 years after our first visit, to test for common proper motion of these candidate companions, and determine if any of this sources is physically associated with eta Corvi. A positive identification of a substellar-mass companions (one of which could be a 3-5 MJ planet at ~360 AU from the star) would be a significant step in understanding the processes leading to LHB-like events in a system analogous to the Solar System.

BATMAN flies: a compact spectro-imager for space observation

NASA Astrophysics Data System (ADS)

Zamkotsian, Frederic; Ilbert, Olivier; Zoubian, Julien; Delsanti, Audrey; Boissier, Samuel; Lancon, Ariane

2014-08-01

BATMAN flies is a compact spectro-imager based on MOEMS for generating reconfigurable slit masks, and feeding two arms in parallel. The FOV is 25 x 12 arcmin2 for a 1m telescope, in infrared (0.85-1.7μm) and 500-1000 spectral resolution. Unique science cases for Space Observation are reachable with this deep spectroscopic multi-survey instrument: deep survey of high-z galaxies down to H=25 on 5 deg2 with continuum detection and all z>7 candidates at H=26.2 over 5 deg2; deep survey of young stellar clusters in nearby galaxies; deep survey of the Kuiper Belt of ALL known objects down to H=22. Pathfinder towards BATMAN in space is already running with ground-based demonstrators.

KSC-05pd2409

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is shrouded in insulating blankets that were installed to serve as a heat shield. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

The Surface Age of Sputnik Planum, Pluto, Must Be Less than 10 Million Years

PubMed Central

Trilling, David E.

2016-01-01

Data from the New Horizons mission to Pluto show no craters on Sputnik Planum down to the detection limit (2 km for low resolution data, 625 m for high resolution data). The number of small Kuiper Belt Objects that should be impacting Pluto is known to some degree from various astronomical surveys. We combine these geological and telescopic observations to make an order of magnitude estimate that the surface age of Sputnik Planum must be less than 10 million years. This maximum surface age is surprisingly young and implies that this area of Pluto must be undergoing active resurfacing, presumably through some cryo-geophysical process. We discuss three possible resurfacing mechanisms and the implications of each one for Pluto’s physical properties. PMID:26790001

KSC-05pd2407

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts part of the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2632A

NASA Image and Video Library

2005-12-16

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, technicians monitor New Horizons as it is lowered onto a transporter for its move to Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2408a

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2407a

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts the blanket that is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2636

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - A Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility awaits the arrival of New Horizons at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2633

NASA Image and Video Library

2005-12-16

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, New Horizons sits atop a transporter awaiting its move to Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2625

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - The mission decal for New Horizons is laid out in strips on the floor of the Payload Hazardous Servicing Facility before installation onto the spacecraft's fairing. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2634

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - New Horizons leaves the Payload Hazardous Servicing Facility before dawn for its journey to the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2635

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - Technicians prepare to move New Horizons before dawn from the Payload Hazardous Servicing Facility to the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2637

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - New Horizons arrives at the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station where buildup of its Lockheed Martin Atlas V launch vehicle is complete. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2639

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing lifting fixture is secured to the nose of the fairing enclosing New Horizons at the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2630

NASA Image and Video Library

2005-12-16

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, technicians prepare to lift New Horizons to a transporter for its move to Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2642

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing enclosing New Horizons arrives at the top of a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2406

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory are installing blankets that serve as heat shields around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

Exploring the Trans-Neptunian Solar System

NASA Astrophysics Data System (ADS)

1998-01-01

A profound question for scientists, philosophers and, indeed, all humans concerns how the solar system originated and subsequently evolved. To understand the solar system's formation, it is necessary to document fully the chemical and physical makeup of its components today, particularly those parts thought to retain clues about primordial conditions and processes.] In the past decade, our knowledge of the outermost, or trans-neptunian, region of the solar system has been transformed as a result of Earth-based observations of the Pluto-Charon system, Voyager 2's encounter with Neptune and its satellite Triton, and recent discoveries of dozens of bodies near to or beyond the orbit of Neptune. As a class, these newly detected objects, along with Pluto, Charon, and Triton, occupy the inner region of a hitherto unexplored component of the solar system, the Kuiper Belt. The Kuiper Belt is believed to be a reservoir of primordial objects of the type that formed in the solar nebula and eventually accreted to form the major planets. The Kuiper Belt is also thought to be the source of short-period comets and a population of icy bodies, the Centaurs, with orbits among the giant planets. Additional components of the distant outer solar system, such as dust and the Oort comet cloud, as well as the planet Neptune itself, are not discussed in this report. Our increasing knowledge of the trans-neptunian solar system has been matched by a corresponding increase in our capabilities for remote and in situ observation of these distant regions. Over the next 10 to 15 years, a new generation of ground- and space-based instruments, including the Keck and Gemini telescopes and the Space Infrared Telescope Facility, will greatly expand our ability to search for and conduct physical and chemical studies on these distant bodies. Over the same time span, a new generation of lightweight spacecraft should become available and enable the first missions designed specifically to explore the icy bodies that orbit 30 astronomical units (AU) or more from the Sun. The combination of new knowledge, plus the technological capability to greatly expand this knowledge over the next decade or so, makes this a particularly opportune time to review current understanding of the trans-neptunian solar system and to begin planning for the future exploration of this distant realm. Based on current knowledge, studies of trans-neptunian objects are important for a variety of reasons that can be summarized under five themes: (1) Exploration of new territory; (2) reservoirs of primitive materials; (3) Processes that reveal the solar system's origin and evolution; (4) Links to extrasolar planets; and (5) prebiotic chemistry. These five themes are not on an equal footing. The first three are well-established areas of scientific investigation and are backed up by a substantial body of observational and theoretical understanding. The last two, however are more speculative. They are included here because they raise a number of interesting possibilities that seem particularly suited to an interdisciplinary approach uniting planetary scientists with their colleagues in the astrophysical and life science communities. Although not considered in any detail in this report, the distant outer solar system also has direct relevance to Earth and the other terrestrial planets because it is the source of comets that bring volatiles into the inner solar system. The resulting inevitable impacts between comets and other planetary bodies can play major roles in the evolution of life as suggested by, for example, the Cretaceous-tertiary boundary bolide and the extinction of the dinosaurs.

A Ninth Planet in Our Solar System?

NASA Astrophysics Data System (ADS)

Kohler, Susanna

2016-01-01

The recent discovery that the orbits of some Kuiper belt objects (KBOs) share properties has proved puzzling. A pair of scientists have now proposed a bold explanation: there may be a planet-sized object yet undetected in our solar system.Mysterious ClusteringKBOs, the population of mainly small objects beyond Neptune, have proven an especially interesting subject of study in the last decade as many small, distant bodies (such as Eris, the object that led to the demotion of Pluto to dwarf planet) have been discovered.Previous studies have recently discovered that some especially distant KBOs those that orbit with semimajor axes of a 150 AU, nearly four times that of Pluto all cross the ecliptic at a similar phase in their elliptical trajectories. This is unexpected, since gravitational tugs from the giant planets should have randomized this parameter over our solar systems multi-billion-year lifespan.Physical alignment of the orbits of Kuiper belt objects with a 250 AU (and two objects with a 150 AU that are dynamically stable). [Batygin Brown 2016]Two scientists at California Institute of Technology, Konstantin Batygin and Michael Brown (you might recognize Brown as the man who killed Pluto) have now increased the mystery. In a recently published a study, they demonstrate that for KBOs that have orbits with a 250 AU, the orbits are actually physically aligned.To explain this unexpected alignment which Batygin and Brown calculate has only a 0.007% probability of having occurred by chance the authors ask an exciting question: could this be caused by the presence of an unseen, large, perturbing body further out in the solar system?Simulating a Ninth PlanetThe authors test this hypothesis by carrying out both analytical calculations and numerical N-body simulations designed to determine if the gravitational influence of a distant, planetary-mass companion can explain the behavior we observe from the large-orbit KBOs.Simulation of the effect of a distant planet (M = 10 M, a = 700 AU, and e = 0.6) on KBOs; click for a better look! The perihelion position of KBOs with a 250 AU clusters around 180 from the perihelion position of the perturbing planet. More-transparent points are less observable. [Batygin Brown 2016]The result? It turns out that such a distant planet can cause the orbits of KBOs with a 250 AU to all align in the opposite direction of the orbit of the planet. Whats more, the gravitational pull of this planet can also explain other unresolved puzzles about the Kuiper belt, such as the presence of high-perihelion Sedna-like objects, as well as a population of KBOs weve observed that have misaligned orbits.Unfortunately, Batygin and Brown found it isnt possible to exactly determine the properties of the possible planet, since multiple combinations of its mass, eccentricity, and semimajor axis can create the same observational results. That said, they believe the distant perturbers orbit is highly eccentric, its orbital inclination is low, and its fairly massive (since anything less than an Earth-mass wont create the observed clustering of KBO orbits within the age of the solar system).As an example, one possible set of parameters that approximately reproduces the observed KBO orbits is the following:planet mass of 10 Earth-massessemi-major axis of a = 700 AUeccentricity of e = 0.6This would correspond to a perihelion distance of 280 AU and an aphelion distance of 1,120 AU.The authors speculate such a planet might have been formed closer in to the Sun, but it was ejected later on during our solar systems evolution. Interactions with the Suns birth cluster could have then caused the planet to be retained in a bound orbit.Future TestsOur solar system on a logarithmic scale (click for the full view). KBOs with a semimajor axis of a 250 AU may be being aligned by a planetary-mass body with an even more distant orbit. [NASA]How can we test this hypothesis of a ninth planet? Obviously, directly observing the planet would confirm its presence. But the authors model has an additional testable hypothesis: if its correct, there should be a population of high-perihelion Kuiper belt objects that dont exhibit the same alignment of their orbits as the KBOs we know about, but instead have opposite-aligned orbits. If we discover such a collection of objects, that would be an excellent confirmation of this model.The authors caution that their work is preliminary, and additional investigation will be required to better understand the possibilities presented here. But with any luck, future theoretical work, as well as observational tests of this models predictions, will help us determine whether there might be a distant ninth planet in our solar system!BonusCheck out this video (created with WWT!), which walks us first through a view of the six aligned KBO orbits, then shows a possible orbit for the hypothesized planet, and then shows an additional population of already-discovered objects (also predicted by the model) that have orbits perpendicular both to the plane of the solar system and to the planets orbit. [Caltech/Robert Hurt]http://aasnova.org/wp-content/uploads/2016/01/Planet9_anim_720.m4vCitationKonstantin Batygin and Michael E. Brown 2016 AJ 151 22. doi:10.3847/0004-6256/151/2/22

De-biased populations of Kuiper belt objects from the deep ecliptic survey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adams, E. R.; Benecchi, S. D.; Gulbis, A. A. S.

2014-09-01

The Deep Ecliptic Survey (DES) was a survey project that discovered hundreds of Kuiper Belt objects from 1998 to 2005. Extensive follow-up observations of these bodies has yielded 304 objects with well-determined orbits and dynamical classifications into one of several categories: Classical, Scattered, Centaur, or 16 mean-motion resonances with Neptune. The DES search fields are well documented, enabling us to calculate the probability on each frame of detecting an object with its particular orbital parameters and absolute magnitude at a randomized point in its orbit. The detection probabilities range from a maximum of 0.32 for the 3:2 resonant object 2002more » GF {sub 32} to a minimum of 1.5 × 10{sup –7} for the faint Scattered object 2001 FU {sub 185}. By grouping individual objects together by dynamical classes, we can estimate the distributions of four parameters that define each class: semimajor axis, eccentricity, inclination, and object size. The orbital element distributions (a, e, and i) were fit to the largest three classes (Classical, 3:2, and Scattered) using a maximum likelihood fit. Using the absolute magnitude (H magnitude) as a proxy for the object size, we fit a power law to the number of objects versus H magnitude for eight classes with at least five detected members (246 objects). The Classical objects are best fit with a power-law slope of α = 1.02 ± 0.01 (observed from 5 ≤ H ≤ 7.2). Six other dynamical classes (Scattered plus five resonances) have consistent magnitude distribution slopes with the Classicals, provided that the absolute number of objects is scaled. Scattered objects are somewhat more numerous than Classical objects, while there are only a quarter as many 3:2 objects as Classicals. The exception to the power law relation is the Centaurs, which are non-resonant objects with perihelia closer than Neptune and therefore brighter and detectable at smaller sizes. Centaurs were observed from 7.5 < H < 11, and that population is best fit by a power law with α = 0.42 ± 0.02. This is consistent with a knee in the H-distribution around H = 7.2 as reported elsewhere. Based on the Classical-derived magnitude distribution, the total number of objects (H ≤ 7) in each class is: Classical (2100 ± 300 objects), Scattered (2800 ± 400), 3:2 (570 ± 80), 2:1 (400 ± 50), 5:2 (270 ± 40), 7:4 (69 ± 9), 5:3 (60 ± 8). The independent estimate for the number of Centaurs in the same H range is 13 ± 5. If instead all objects are divided by inclination into 'Hot' and 'Cold' populations, following Fraser et al., we find that α{sub Hot} = 0.90 ± 0.02, while α{sub Cold} = 1.32 ± 0.02, in good agreement with that work.« less

Dynamical Zodiacal Cloud Models Constrained by High Resolution Spectroscopy of the Zodiacal Light

NASA Technical Reports Server (NTRS)

Ipatov, S. I.; Kutyrev, A. S.; Madsen, G. J.; Mather, J. C.; Moseley, S. H.; Reynolds, R. J.

2005-01-01

We have developed a set of self-consistent dynamical models of the Zodiacal cloud, following the orbital evolution of dust particles. Three populations were considered, originating from the Kuiper belt, asteroids and comets. Using the models developed, we investigated how the solar spectrum is changed by scattering by the zodiacal cloud grains and compared the obtained spectra with the observations.

OBSERVATIONAL SIGNATURES OF A MASSIVE DISTANT PLANET ON THE SCATTERING DISK

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawler, S. M.; Kavelaars, J. J.; Shankman, C.

The orbital element distribution of trans-Neptunian objects (TNOs) with large pericenters has been suggested to be influenced by the presence of an undetected, large planet at >200 au from the Sun. To find additional observables caused by this scenario, we present here the first detailed emplacement simulation in the presence of a massive ninth planet on the distant Kuiper Belt. We perform 4 Gyr N -body simulations with the currently known solar system planetary architecture, plus a 10  M {sub ⊕} planet with similar orbital parameters to those suggested by Trujillo and Sheppard or Batygin and Brown, and 10{sup 5} testmore » particles in an initial planetesimal disk. We find that including a distant super-Earth-mass planet produces a substantially different orbital distribution for the scattering and detached TNOs, raising the pericenters and inclinations of moderate semimajor axis (50 <  a  < 500 au) objects. We test whether this signature is detectable via a simulator with the observational characteristics of four precisely characterized TNO surveys. We find that the qualitatively very distinct solar system models that include a ninth planet are essentially observationally indistinguishable from an outer solar system produced solely by the four giant planets. We also find that the mass of the Kuiper Belt’s current scattering and detached populations is required to be 3–10 times larger in the presence of an additional planet. We do not find any evidence for clustering of orbital angles in our simulated TNO population. Wide-field, deep surveys targeting inclined high-pericenter objects will be required to distinguish between these different scenarios.« less

Signatures of planets: Observations and modeling of structure in the zodiacal cloud and Kuiper disk

NASA Astrophysics Data System (ADS)

Holmes, Elizabeth Katherine

2002-12-01

There is a possible connection between structure in evolved circumstellar disks and the presence of planets, our own zodiacal cloud being a proven example. Asymmetries in such a disk could be diagnostic of planets which would be otherwise undetectable. Using COBE DIRBE observations, we link structure in the zodiacal cloud, namely the warp and offset of the cloud, to the presence of planets using secular perturbation theory. In addition, we obtain supplementary ISO observations and determine a scale factor for the data which we apply to calibrate the data to the observed COBE brightness. A Kuiper dust disk will have a resonant structure, with two concentrations in brightness along the ecliptic longitude arising because 10 15% of the Kuiper belt objects are in the 3:2 mean motion resonance with Neptune. We run numerical integrations of particles originating from source bodies trapped in the 3:2 resonance and we determine what percentage of particles remain in the resonance for a variety of particle and source body sizes. The dynamical evolution of the particles is followed from source to sink with Poynting- Robertson light drag, solar wind drag, radiation pressure, the Lorentz force, neutral interstellar gas drag, and the effects of planetary gravitational perturbations included. We then conduct an observational search in the 60 μm COBE data for the Kuiper disk, which is predicted to be, at most, a few percent of the brightness of the zodiacal cloud. By removing emission due to the background zodiacal cloud and the dust bands, we expect to see the trailing/leading signature of Earth's resonant ring. However, when subtracted from the data, we find that none of the empirical background zodiacal cloud models give the residuals predicted by theory. We conclude that a dynamical two-component (both inner and outer) zodiacal cloud model must be created to complete the search. Lastly, we extend our work outside the solar system and obtain upper limits on the flux around ten Vega-type stars using the Sub-millimeter Telescope Observatory in the 870 μm and 1300 μm wave bands, which will be used to determine the most promising candidates for future observations.

Solar system astronomy with the 3.6-m DOT and the 4-m ILMT

NASA Astrophysics Data System (ADS)

Ganesh, Shashikiran; Venkataramani, Kumar; Baliyan, Kiran Singh; Joshi, Umesh Chandra

2018-04-01

Solar system astronomy would be an important field of study with the 3.6-m Devasthal Optical Telescope (DOT) and the 4-m International Liquid Mirror Telescope (ILMT). In this contribution, we highlight the work that could be done in reaching a better understanding of the Solar system and its constituents - particularly the minor bodies and other smaller objects. There may be a large number of very faint objects in the vicinity of the Earth orbit. In fact only recently a 'second moon' of the Earth has been found and has been designated 2016 H03. This is a quasi-satellite with the same period of revolution around Earth and Sun. There could be many such objects and it is important to have a full characterization and understanding of these potentially hazardous objects. They are generally fainter than 18th magnitude and one would need a lot of telescope time to fully characterize these objects using techniques of spectropolarimetry. In a similar fashion, a deep census of the Kuiper Belt Objects and the TNOs is needed. In this census, the concept of pencil beam surveys could be extended to cylindrical transit imaging technique available with the 4-m ILMT.

Dynamical history of the asteroid belt and implications for terrestrial pla net bombardment

NASA Astrophysics Data System (ADS)

Minton, David Andrew

The main asteroid belt spans ~ 2-4 AU in heliocentric distance and is sparsely populated by rocky debris. The dynamical structure of the main belt records clues to past events in solar system history. Evidence from the structure of the Kuiper belt, an icy debris belt beyond Neptune, suggests that the giant planets were born in a more compact configuration and later experienced planetesimal-driven planet migration. Giant planet migration caused both mean motion and secular resonances to sweep across the main asteroid belt, raising the eccentricity of asteroids into planet-crossing orbits and depleting the belt. I show that the present-day semimajor axis and eccentricity distributions of large main belt asteroids are consistent with excitation and depletion due to resonance sweeping during the epoch of giant planet migration. I also use an analytical model of the sweeping of the n 6 secular resonance, to set limits on the migration speed of Saturn. After planet migration, dynamical chaos became the dominant loss mechanism for asteroids with diameters D [Special characters omitted.] 10 km in the current asteroid belt. I find that the dynamical loss history of test particles from this region is well described with a logarithmic decay law. My model suggests that the rate of impacts from large asteroids may have declined by a factor of three over the last ~ 3 Gy, and that the present-day impact flux of D > 10 km objects on the terrestrial planets is roughly an order of magnitude less than estimates used in crater chronologies and impact hazard risk assessments. Finally, I have quantified the change in the solar wind 6 Li/ 7 Li ratio due to the estimated in-fall of chondritic material and enhanced dust production during the epoch of planetesimal-driven giant planet migration. The solar photosphere is currently highly depleted in lithium relative to chondrites, and 6 Li is expected to be far less abundant in the sun than 7 Li due to the different nuclear reaction rates of the two isotopes. Evidence for a short- lived impact cataclysm that affected the entire inner solar system may be found in the composition of implanted solar wind particles in lunar regolith.

A thick cloud of Neptune Trojans and their colors.

PubMed

Sheppard, Scott S; Trujillo, Chadwick A

2006-07-28

The dynamical and physical properties of asteroids offer one of the few constraints on the formation, evolution, and migration of the giant planets. Trojan asteroids share a planet's semimajor axis but lead or follow it by about 60 degrees near the two triangular Lagrangian points of gravitational equilibrium. Here we report the discovery of a high-inclination Neptune Trojan, 2005 TN(53). This discovery demonstrates that the Neptune Trojan population occupies a thick disk, which is indicative of "freeze-in" capture instead of in situ or collisional formation. The Neptune Trojans appear to have a population that is several times larger than the Jupiter Trojans. Our color measurements show that Neptune Trojans have statistically indistinguishable slightly red colors, which suggests that they had a common formation and evolutionary history and are distinct from the classical Kuiper Belt objects.

WFIRST: Guest observer science with the coronagraph instrument

NASA Astrophysics Data System (ADS)

Levesque, Emily; Lomax, Jamie; Akeson, Rachel; Meshkat, Tiffany; WFIRST CGI GO working group

2018-01-01

In addition to the discovery and characterization of exoplanets, the coronagraph instrument (CGI) on WFIRST has the potential for ground-breaking discoveries in other fields through the Guest Observer (GO) program. 25% of the observing time in the primary mission will be made available to the GO community, and GO science with the CGI spans a broad range of scientific applications. These include imaging of binary and multiple asteroids and Kuiper Belt objects, the circumstellar environments of evolved giants and supergiants, debris disks around young stars, and the circumnuclear regions of active galactic nuclei. In this poster we summarize some of the key compelling science gains that can be pursued with the GO program and present preliminary analyses of the technical gains that the CGI will be able to offer over other contemporary coronagraphs, including those on JWST and ground-based observatories.

KSC-05pd2592

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, clean-suit garbed workers secure the fairing sections around the New Horizons spacecraft for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2641

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing lifting fixture raises the fairing enclosing New Horizons to the top of a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2615

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - At their consoles in the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, members of the New Horizons team take part in a dress rehearsal for the launch scheduled in mid-January. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2646

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing enclosing New Horizons awaits further processing upon its arrival atop a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2408

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory adjusts part of the blanket that it is being installed as a heat shield around the New Horizons spacecraft. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2628

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - Technicians install strips of the New Horizons mission decal on the spacecraft fairing in the Payload Hazardous Servicing Facility. The last strip will be installed on the fairing after the spacecraft is delivered to Pad 41 on Dec. 17. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2644

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - Technicians monitor the fairing enclosing New Horizons as it is lowered onto the top of a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2647

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing enclosing New Horizons awaits further processing upon its arrival atop a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2645

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - Technicians monitor the fairing enclosing New Horizons as it is positioned atop a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2614

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - At their consoles in the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, members of the New Horizons team take part in a dress rehearsal for the launch scheduled in mid-January. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2590

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections move into place around the New Horizons spacecraft for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2629

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - Technicians install strips of the New Horizons mission decal on the spacecraft fairing in the Payload Hazardous Servicing Facility. The last strip will be installed on the fairing after the spacecraft is delivered to Pad 41 on Dec. 17. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2591

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections close in around the New Horizons spacecraft to encapsulate it. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2627

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - Technicians install strips of the New Horizons mission decal on the spacecraft fairing in the Payload Hazardous Servicing Facility. The last strip will be installed on the fairing after the spacecraft is delivered to Pad 41 on Dec. 17. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2589

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the New Horizons spacecraft waits for encapsulation within the fairing sections waiting nearby. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2640

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing lifting fixture lifts the fairing enclosing New Horizons to the top of a Lockheed Martin Atlas V launch vehicle at the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

The Dynamical Structure of HR 8799's Inner Debris Disk

NASA Astrophysics Data System (ADS)

Contro, B.; Wittenmyer, Robert A.; Horner, J.; Marshall, Jonathan P.

2015-06-01

The HR 8799 system, with its four giant planets and two debris belts, has an architecture closely mirroring that of our Solar system where the inner, warm asteroid belt and outer, cool Edgeworth-Kuiper belt bracket the giant planets. As such, it is a valuable laboratory for examining exoplanetary dynamics and debris disk-exoplanet interactions. Whilst the outer debris belt of HR 8799 has been well resolved by previous observations, the spatial extent of the inner disk remains unknown. This leaves a significant question mark over both the location of the planetesimals responsible for producing the belt's visible dust and the physical properties of those grains. We have performed the most extensive simulations to date of the inner, unresolved debris belt around HR 8799, using UNSW Australia's Katana supercomputing facility to follow the dynamical evolution of a model inner disk comprising 300,298 particles for a period of 60 Ma. These simulations have enabled the characterisation of the extent and structure of the inner disk in detail, and will in future allow us to provide a first estimate of the small-body impact rate and water delivery prospects for possible (as-yet undetected) terrestrial planet (s) in the inner system.

The dynamical structure of the HR8799 inner debris disk

NASA Astrophysics Data System (ADS)

Wittenmyer, Robert A.; Contro de Godoy, Bruna; Horner, Jonathan; Marshall, Jonathan P.

2014-11-01

The HR 8799 system, with its four giant planets and two debris belts, has an architecture closely mirroring that of our Solar System where the inner, warm asteroid belt and outer, cool Edgeworth-Kuiper belt bracket the giant planets. As such, it is a valuable laboratory for examining exoplanet dynamics and debris disc-exoplanet interactions. Whilst the outer debris belt of HR 8799 has been well resolved by previous observations, the spatial extent of the inner disc remains unknown, leaving a question mark over both the location of the planetesimals responsible for producing the belt's visible dust and the physical properties of those grains. We have performed the most extensive simulations to date of the inner, unresolved debris belt around HR 8799, using University of New South Wales's Katana supercomputing facility to follow the dynamical evolution of a model inner disc comprising 250,000 particles for a period of 100 million years. These simulations will (1) characterise the extent and structure of the inner disk in detail and (2) provide the first estimate of the small-body impact rate and water delivery prospects for possible (as-yet undetected) terrestrial planet(s) in the inner system.

The Dynamical Structure of HR 8799's Inner Debris Disk.

PubMed

Contro, B; Wittenmyer, Robert A; Horner, J; Marshall, Jonathan P

2015-06-01

The HR 8799 system, with its four giant planets and two debris belts, has an architecture closely mirroring that of our Solar system where the inner, warm asteroid belt and outer, cool Edgeworth-Kuiper belt bracket the giant planets. As such, it is a valuable laboratory for examining exoplanetary dynamics and debris disk-exoplanet interactions. Whilst the outer debris belt of HR 8799 has been well resolved by previous observations, the spatial extent of the inner disk remains unknown. This leaves a significant question mark over both the location of the planetesimals responsible for producing the belt's visible dust and the physical properties of those grains. We have performed the most extensive simulations to date of the inner, unresolved debris belt around HR 8799, using UNSW Australia's Katana supercomputing facility to follow the dynamical evolution of a model inner disk comprising 300,298 particles for a period of 60 Ma. These simulations have enabled the characterisation of the extent and structure of the inner disk in detail, and will in future allow us to provide a first estimate of the small-body impact rate and water delivery prospects for possible (as-yet undetected) terrestrial planet (s) in the inner system.

Some aspects of the cosmogonic outward migration of Neptune. Co-planar migration

NASA Astrophysics Data System (ADS)

Neslušan, L.; Jakubík, M.

2013-10-01

Considering a simple model of the cosmogonic outward migration of Neptune, we investigate if the assumption of an extremely low orbital inclination of small bodies in a once-existing proto-planetary disk could influence the structure of reservoirs of the objects in the trans-Neptunian region. We found no significant influence. Our models predict only the existence of the mean-motion resonances (MMRs) with Neptune 2:3, 3:5, 1:2, and an anemic scattered disk (MMRs 3:4, 5:7, and 9:11 are also indicated). To explain the classical Edgeworth-Kuiper belt, relatively abundant 4:7 and 2:5 MMRs, and the more numerous scattered disk, we need to assume that, e.g., the outer boundary of the original proto-planetary disk considerably exceeded the distance of the current Neptune's orbit (Neptune probably ended its migration at the distance, where the disk's density started to be sub-critical), or that some Pluto-sized objects resided inside the MMRs and in the distant parts of the original proto-planetary disk.

The Dynamical Imprint of Lost Protoplanets on the Trans-Neptunian Populations, and Limits on the Primordial Size Distribution of Trans-Neptunian Objects at Pluto and Larger Sizes.

NASA Astrophysics Data System (ADS)

Shannon, Andrew Brian; Dawson, Rebekah

2018-04-01

Planet formation remains a poorly understood process, in part because of our limited access to the intermediate phases of planetesimal and protoplanet growth. Today, the vast majority of the accessible remaining planetesimals and protoplanets reside within the Hot Trans-Neptunian Object population. This population has been depleted by 99% - 99.9% over the course of the Solar system's history, and as such the present day size-number distribution may be incomplete at the large size end. We show that such lost protoplanets would have left signatures in the dynamics of the present-day Trans-Neptunian Populations, and their primordial number can thus be statistically limited by considering the survival of ultra-wide binary TNOs, the Cold Classical Kuiper belt, and the resonant populations. We compare those limits to the predicted size-number distribution of various planetesimal and proto-planet growth models.

The Advanced Jovian Asteroid Explorer (AJAX)

NASA Astrophysics Data System (ADS)

Murchie, S. L.; Adams, E. Y.; Mustard, J. F.; Rivkin, A.; Peplowski, P. N.

2015-12-01

The Advanced Jovian Asteroid eXplorer (AJAX) is the first mission to characterize the geology, morphology, geophysical properties, and chemistry of a Trojan asteroid. The Decadal Survey outlined a notional New Frontiers class Trojan asteroid rendezvous mission to conduct geological, elemental composition, mineralogical, and geophysical investigations. AJAX, our Discovery mission proposal, addresses the Decadal Survey science goals by using a focused payload and an innovative mission design. By responding to the most important questions about the Trojan asteroids, AJAX advances our understanding of all of the Solar System. Are these objects a remnant population of the local primordial material from which the outer planets and their satellites formed, or did they originate in the Kuiper Belt? Landed measurements of major and minor elements test hypotheses for the Trojan asteroid origin, revealing the outer Solar System dynamical history. How and when were prebiotic materials delivered to the terrestrial planets? AJAX's landed measurements include C and H concentrations, necessary to determine their inventories of volatiles and organic compounds, material delivered to the inner Solar System during the Late Heavy Bombardment. What chemical and geological processes shaped the small bodies that merged to form the planets in our Solar System? AJAX investigates the asteroid internal structure, geology, and regolith by using global high-resolution stereo and multispectral imaging, determining density and estimating interior porosity by measuring gravity, and measuring regolith mechanical properties by landing. AJAX's science phase starts with search for natural satellites and dust lifted by possible cometary activity and shape and pole position determination. AJAX descends to lower altitudes for global mapping, and conducts a low flyover for high-resolution surface characterization and measurement of hydrogen abundance. Finally, it deploys a small landed package, which measures elemental abundances and physical properties of the regolith. AJAX's science data will result in an improved understanding of the early stages of planetary accretion by comparing a Trojan asteroid with near-Earth targets of OSIRIS-REx, Hayabusa 2, and NEAR, and the Kuiper Belt-derived targets of Rosetta and New Horizons.

Dynamic Tensile Strength of Low Temperature Ice and Kuiper Belt Size Distributions

NASA Astrophysics Data System (ADS)

Ahrens, Thomas J.; Fat'yanov, O. V.; Engelhardt, H.; Fraser, W. C.

2009-09-01

We model mutual gravitationally driven impact interactions in a nearly gas-free environment of the Kuiper belt (KB) and use low-temperature (< 100 K) ice dynamic strength dependent collisional out-come (accretion vs. erosion and fragmentation) models. These lead to theoretically predictable distributions of object number density, vs. mass distributions. These derived mass distributions are comparable to the now rapidly growing KB survey data. Tensional failure of single and polycrystalline ice in the temperature range from 263 to 128 K was measured for high strain rate, c.a. 104 s-1, dynamic loading conditions. Experiments, similar to Lange and Ahrens(1991)(LA), were conducted using a gas gun launched Lexan projectile. The liquid nitrogen cooled ice target approaching KB-like temperatures was partially confined, rather than using the LA confined geometry. Another set of experiments used a drop tube projectile launcher within the 263 K Caltech Ice Laboratory and at 163 K in a liquid nitrogen cooled chamber. New experiments give tensile strengths of 7.6±1.5 MPa at 263 K and 9.1±1.5 MPa at 163 K for unconfined, free of visual initial defects and measurable imperfections ice samples. The new strengths are lower than the earlier LA data ( 17 MPa). The major differences arise from ice target assembly. LA used polycrystalline ice samples confined in annular stainless steel target rings. New measurements were partially confined, in not initially contacting concentric target rings. Later shots used unconfined configurations with ice pellets affixed to aluminum foil. Circumferential confinement is known to increase the material damage threshold upon both compression and tensile loading. Previous confinement in LA is the main cause of the above discrepancy. Present tensile strengths are only a few times higher than 0.7 - 3.0 MPa summarized in Petrovic (2003) for quasistatic tension at 10-7 to 10-3 s-1 strain rate.

OSSOS. II. A Sharp Transition in the Absolute Magnitude Distribution of the Kuiper Belt’s Scattering Population

NASA Astrophysics Data System (ADS)

Shankman, C.; Kavelaars, JJ.; Gladman, B. J.; Alexandersen, M.; Kaib, N.; Petit, J.-M.; Bannister, M. T.; Chen, Y.-T.; Gwyn, S.; Jakubik, M.; Volk, K.

2016-02-01

We measure the absolute magnitude, H, distribution, dN(H) ∝ 10 αH , of the scattering Trans-Neptunian Objects (TNOs) as a proxy for their size-frequency distribution. We show that the H-distribution of the scattering TNOs is not consistent with a single-slope distribution, but must transition around H g ˜ 9 to either a knee with a shallow slope or to a divot, which is a differential drop followed by second exponential distribution. Our analysis is based on a sample of 22 scattering TNOs drawn from three different TNO surveys—the Canada-France Ecliptic Plane Survey, Alexandersen et al., and the Outer Solar System Origins Survey, all of which provide well-characterized detection thresholds—combined with a cosmogonic model for the formation of the scattering TNO population. Our measured absolute magnitude distribution result is independent of the choice of cosmogonic model. Based on our analysis, we estimate that the number of scattering TNOs is (2.4-8.3) × 105 for H r < 12. A divot H-distribution is seen in a variety of formation scenarios and may explain several puzzles in Kuiper Belt science. We find that a divot H-distribution simultaneously explains the observed scattering TNO, Neptune Trojan, Plutino, and Centaur H-distributions while simultaneously predicting a large enough scattering TNO population to act as the sole supply of the Jupiter-Family Comets.

Planetary Science Enabled by High Power Ion Propulsion Systems from NASA's Prometheus Program

NASA Astrophysics Data System (ADS)

Cooper, John

2004-11-01

NASA's Prometheus program seeks to develop new generations of spacecraft nuclear-power and ion propulsion systems for applications to future planetary missions. The Science Definition Team for the first mission in the Prometheus series, the Jupiter Icy Moons Orbiter (JIMO), has defined science objectives for in-situ orbital exploration of the icy Galilean moons (Europa, Ganymede, Callisto) and the Jovian magnetosphere along with remote observations of Jupiter's atmosphere and aurorae, the volcanic moon Io, and other elements of the Jovian system. Important to this forum is that JIMO power and propulsion systems will need to be designed to minimize magnetic, radio, neutral gas, and plasma backgrounds that might otherwise interfere with achievement of mission science objectives. Another potential Prometheus mission of high science interest would be an extended tour of primitive bodies in the solar system, including asteroids, Jupiter family comets, Centaurs, and Kuiper Belt Objects (KBO). The final landed phase of this mission might include an active keplerian experiment for detectable (via downlink radio doppler shift) acceleration of a small kilometer-size Centaur or KBO object, likely the satellite of a larger object observable from Earth. This would have obvious application to testing of mitigation techniques for Earth impact hazards.

Albedos of Small Hilda Asteroids

NASA Astrophysics Data System (ADS)

Ryan, Erin L.; Woodward, C. E.

2010-10-01

We present albedo results for 70 small Hilda dynamical family members detected by the Spitzer Space Telescope in multiple archival programs. This Spitzer data samples Hildas with diameters between 2 and 11 kilometers. Our preliminary analysis reveals that the mean geometric albedo for this sample is pv = 0.05, matching the mean albedo derived for large (20 to 160 km) Hilda asteroids observed by IRAS (Ryan and Woodward 2010). This mean albedo is significantly darker than the mean albedo of asteroids in the outer main belt (2.8 AU < a < 3.5 AU), possibly suggesting that these asteroids did not originate from the outer main belt . This is in direct conflict with some dynamical models which suggest that the HIldas are field asteroids trapped from an inward migration of Jupiter (Franklin et al. 2004), and may provide additional observation support for delivery of dark Kuiper Belt contaminants to the inner solar system as per the Nice Model (Levison et al. 2009).

Physical observations of comets: Their composition, origin and evolution

NASA Technical Reports Server (NTRS)

Cochran, Anita L.; Barker, Edwin S.; Cochran, William D.

1991-01-01

The composition, origins, and evolution of comets were studied. The composition was studied using spectroscopic observations of primarily brighter comets at moderate and high resolution for the distribution of certain gases in the coma. The origins was addressed through an imaging search for the Kuiper belt of comets. The evolution was addressed by searching for a link between comets and asteroids using an imaging approach to search for an OH coma.

Detection of CO and Ethane in Comet 21P/Giacobini-Zinner: Evidence for Variable Chemistry in the Outer Solar Nebula

NASA Technical Reports Server (NTRS)

Mumma, M. J.; DiSanti, M. A.; DelloRusso, N.; Magee-Sauer, K.; Rettig, T. W.

1999-01-01

Ethane and carbon monoxide were detected in a short-period comet of probable Kuiper belt origin. Ethane is substantially less abundant compared with Hyakutake and Hale-Bopp, two comets from the giant-planets region of the solar nebula, suggesting a heliocentric gradient in ethane in pre-cometary ices. It is argued that processing by X-rays from the young sun may be responsible.

Detection of CO and Ethane in Comet 21P/Giacobini-Zinner: Evidence for Variable Chemistry in the Outer Solar Nebula.

PubMed

Mumma; DiSanti; Dello Russo N; Magee-Sauer; Rettig

2000-03-10

Ethane and carbon monoxide were detected in a short-period comet of probable Kuiper Belt origin. Ethane is substantially less abundant compared with Hyakutake and Hale-Bopp, two comets from the giant-planet region of the solar nebula, suggesting a heliocentric gradient in ethane in precometary ices. It is argued that processing by X-rays from the young Sun may be responsible.

An Icy Kuiper-Belt Around the Young Solar-Type Star HD 181327

NASA Technical Reports Server (NTRS)

Lebreton, J.; Augereau, J.-C.; Thi, W.-F.; Roberge, A.; Donaldson, J.; Schneider, G.; Maddison, S. T.; Menard, F.; Riviere-Marichalar, P.; Mathews, G. S.;

Solar System Science with LSST

NASA Astrophysics Data System (ADS)

Jones, R. L.; Chesley, S. R.; Connolly, A. J.; Harris, A. W.; Ivezic, Z.; Knezevic, Z.; Kubica, J.; Milani, A.; Trilling, D. E.

2008-09-01

The Large Synoptic Survey Telescope (LSST) will provide a unique tool to study moving objects throughout the solar system, creating massive catalogs of Near Earth Objects (NEOs), asteroids, Trojans, TransNeptunian Objects (TNOs), comets and planetary satellites with well-measured orbits and high quality, multi-color photometry accurate to 0.005 magnitudes for the brightest objects. In the baseline LSST observing plan, back-to-back 15-second images will reach a limiting magnitude as faint as r=24.7 in each 9.6 square degree image, twice per night; a total of approximately 15,000 square degrees of the sky will be imaged in multiple filters every 3 nights. This time sampling will continue throughout each lunation, creating a huge database of observations. Fig. 1 Sky coverage of LSST over 10 years; separate panels for each of the 6 LSST filters. Color bars indicate number of observations in filter. The catalogs will include more than 80% of the potentially hazardous asteroids larger than 140m in diameter within the first 10 years of LSST operation, millions of main-belt asteroids and perhaps 20,000 Trans-Neptunian Objects. Objects with diameters as small as 100m in the Main Belt and <100km in the Kuiper Belt can be detected in individual images. Specialized `deep drilling' observing sequences will detect KBOs down to 10s of kilometers in diameter. Long period comets will be detected at larger distances than previously possible, constrainting models of the Oort cloud. With the large number of objects expected in the catalogs, it may be possible to observe a pristine comet start outgassing on its first journey into the inner solar system. By observing fields over a wide range of ecliptic longitudes and latitudes, including large separations from the ecliptic plane, not only will these catalogs greatly increase the numbers of known objects, the characterization of the inclination distributions of these populations will be much improved. Derivation of proper elements for main belt and Trojan asteroids will allow ever more resolution of asteroid families and their size-frequency distribution, as well as the study of the long-term dynamics of the individual asteroids and the asteroid belt as a whole. Fig. 2 Orbital parameters of Main Belt Asteroids, color-coded according to ugriz colors measured by SDSS. The figure to the left shows osculating elements, the figure to the right shows proper elements - note the asteroid families visible as clumps in parameter space [1]. By obtaining multi-color ugrizy data for a substantial fraction of objects, relationships between color and dynamical history can be established. This will also enable taxonomic classification of asteroids, provide further links between diverse populations such as irregular satellites and TNOs or planetary Trojans, and enable estimates of asteroid diameter with rms uncertainty of 30%. With the addition of light-curve information, rotation periods and phase curves can be measured for large fractions of each population, leading to new insight on physical characteristics. Photometric variability information, together with sparse lightcurve inversion, will allow spin state and shape estimation for up to two orders of magnitude more objects than presently known. This will leverage physical studies of asteroids by constraining the size-strength relationship, which has important implications for the internal structure (solid, fractured, rubble pile) and in turn the collisional evolution of the asteroid belt. Similar information can be gained for other solar system bodies. [1] Parker, A., Ivezic

Jet-like features near the Nucleus of Chiron

NASA Technical Reports Server (NTRS)

Elliot, J. L.; Olkin, C. B.; Dunham, E. W.; Ford, C. H.; Gilmore, D. K.; Kurtz, D.; Lazzaro, D.; Rank, D. M.; Temi, P.; Bandyopadhyay, R. M.;

The Deep Lens Survey : Real--time Optical Transient and Moving Object Detection

NASA Astrophysics Data System (ADS)

Becker, Andy; Wittman, David; Stubbs, Chris; Dell'Antonio, Ian; Loomba, Dinesh; Schommer, Robert; Tyson, J. Anthony; Margoniner, Vera; DLS Collaboration

2001-12-01

We report on the real-time optical transient program of the Deep Lens Survey (DLS). Meeting the DLS core science weak-lensing objective requires repeated visits to the same part of the sky, 20 visits for 63 sub-fields in 4 filters, on a 4-m telescope. These data are reduced in real-time, and differenced against each other on all available timescales. Our observing strategy is optimized to allow sensitivity to transients on several minute, one day, one month, and one year timescales. The depth of the survey allows us to detect and classify both moving and stationary transients down to ~ 25th magnitude, a relatively unconstrained region of astronomical variability space. All transients and moving objects, including asteroids, Kuiper belt (or trans-Neptunian) objects, variable stars, supernovae, 'unknown' bursts with no apparent host, orphan gamma-ray burst afterglows, as well as airplanes, are posted on the web in real-time for use by the community. We emphasize our sensitivity to detect and respond in real-time to orphan afterglows of gamma-ray bursts, and present one candidate orphan in the field of Abell 1836. See http://dls.bell-labs.com/transients.html.

Distant Comets in the Early Solar System

NASA Technical Reports Server (NTRS)

Meech, Karen J.

2000-01-01

The main goal of this project is to physically characterize the small outer solar system bodies. An understanding of the dynamics and physical properties of the outer solar system small bodies is currently one of planetary science's highest priorities. The measurement of the size distributions of these bodies will help constrain the early mass of the outer solar system as well as lead to an understanding of the collisional and accretional processes. A study of the physical properties of the small outer solar system bodies in comparison with comets in the inner solar system and in the Kuiper Belt will give us information about the nebular volatile distribution and small body surface processing. We will increase the database of comet nucleus sizes making it statistically meaningful (for both Short-Period and Centaur comets) to compare with those of the Trans-Neptunian Objects. In addition, we are proposing to do active ground-based observations in preparation for several upcoming space missions.

Search for Dormant Comets in Near-Earth Space

NASA Astrophysics Data System (ADS)

Kim, Yoonyoung

2013-06-01

It is considered that comets have been injected into near-Earth space from outer region (e.g. Kuiper-belt region), providing rich volatile and organic compounds to the earth. Some comets are still active while most of them are dormant with no detectable tails and comae. Here we propose to make a multi-band photometric observation of near-Earth objects (NEOs) with comet-like orbits. We select our targets out of infrared asteroidal catalogs based on AKARI and WISE observations. With a combination of taxonomic types by Subaru observation and albedos by AKARI or WISE, we aim to dig out dormant comet candidates among NEOs. Our results will provide valuable information to figure out the dynamical evolution and fate of comets. We would like to emphasize that this is the first taxonomic survey of dormant comets to utilize the infrared data archive with AKARI and WISE.

Cold compaction of water ice

USGS Publications Warehouse

Durham, W.B.; McKinnon, W.B.; Stern, L.A.

2005-01-01

Hydrostatic compaction of granulated water ice was measured in laboratory experiments at temperatures 77 K to 120 K. We performed step-wise hydrostatic pressurization tests on 5 samples to maximum pressures P of 150 MPa, using relatively tight (0.18-0.25 mm) and broad (0.25-2.0 mm) starting grain-size distributions. Compaction change of volume is highly nonlinear in P, typical for brittle, granular materials. No time-dependent creep occurred on the lab time scale. Significant residual porosity (???0.10) remains even at highest P. Examination by scanning electron microscopy (SEM) reveals a random configuration of fractures and broad distribution of grain sizes, again consistent with brittle behavior. Residual porosity appears as smaller, well-supported micropores between ice fragments. Over the interior pressures found in smaller midsize icy satellites and Kuiper Belt objects (KBOs), substantial porosity can be sustained over solar system history in the absence of significant heating and resultant sintering. Copyright 2005 by the American Geophysical Union.

KSC-05pd2638

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - The fairing lifting fixture is lowered toward the nose of the fairing enclosing New Horizons upon its arrival at the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. A Lockheed Martin Atlas V launch vehicle stands ready to receive it in the background. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

Latitude Variation for Pluto's Crater Distribution

NASA Astrophysics Data System (ADS)

Dwivedi, A. K.; Binzel, R. P.; Earle, A. M.; Singer, K. N.; Stern, A.; Olkin, C.; Weaver, H. A., Jr.; Ennico Smith, K.; Young, L. A.

2017-12-01

The crater population distribution on Pluto and Charon have been studied to infer the size distribution of objects in the Kuiper belt (Singer et al. 2017; submitted). In this talk, we will look at the variation in crater distribution with latitude. To circumvent possible bias effects in the analysis, we focus our analysis on a region having the most consistent imaging resolution afforded by the flyby geometry. The longitudinal extent of our study region is 90E to 150E, and the latitudinal extent is 0°N to 90°N. Our preliminary analysis shows crater population peaks in the latitude range 30°N to 60°N and drops off sharply toward the north pole. Here we describe how we quantify the crater distribution in this region and explore a range of processes for volatile transport over both orbital timescales and perihelion precession timescales, including million year Milankovitch cycles for obliquity oscillations.

KSC-05pd2588

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, the two fairing sections are ready to be moved in place around the New Horizons spacecraft (in center) for encapsulation. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2631

NASA Image and Video Library

2005-12-16

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, technicians lift New Horizons toward a transporter for its move to Complex 41 on Cape Canaveral Air Force Station. The last strip of the mission decal will be installed on the fairing after the spacecraft is delivered to the pad. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2587

NASA Image and Video Library

2005-12-13

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, clean-suit garbed workers prepare the first fairing section (in the background) that will encapsulate the New Horizons spacecraft at left for flight. The fairing protects the spacecraft during launch and flight through the atmosphere. Once out of the atmosphere, the fairing is jettisoned. The compact 1,060-pound New Horizons probe carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2612

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - In the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, Ed Biggs (foreground), a fluids software engineer for Lockheed Martin, and other members of the New Horizons team take part in a dress rehearsal for the launch scheduled in mid-January. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2632

NASA Image and Video Library

2005-12-16

KENNEDY SPACE CENTER, FLA. - In the Payload Hazardous Servicing Facility, technicians lower New Horizons onto a transporter for its move to Complex 41 on Cape Canaveral Air Force Station. The last strip of the mission decal will be installed on the fairing after the spacecraft is delivered to the pad. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2643

NASA Image and Video Library

2005-12-17

KENNEDY SPACE CENTER, FLA. - InDyne employee Mic Miracle captures on video the arrival of the fairing enclosing New Horizons at the top of a Lockheed Martin Atlas V launch vehicle in the Vertical Integration Facility at Complex 41 on Cape Canaveral Air Force Station. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2626

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - A technician installs the first strip of the New Horizons mission decal on the spacecraft fairing in the Payload Hazardous Servicing Facility. The last strip will be installed on the fairing after the spacecraft is delivered to Pad 41 on Dec. 17. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

New objective of the "New Horizons" in the Kuiper belt

NASA Astrophysics Data System (ADS)

Vidmachenko, A. P.

2018-05-01

The scientific purpose of the study of the small planet 2014 MU69 is to obtain characteristics on its geology and morphology, to perform mapping of the surface composition: the search for ammonia, carbon monoxide, methane, water ice, etc. Also, it is planned to study its surface, the history of formation and development, measure the temperature, display the 3D topography in order to find out what it looks like, and by what it is differ, for example, from cometary nuclei, asteroids, dwarf planets, such as Pluto; search for any signs of activity, such as commas, to search for and explore possible satellites and / or rings, determine the mass, and so on. The spacecraft will visit MU69 1.01.2019. It is planned to get closer to its surface at a distance of about 3500 km. This will allow obtaining images of the surface with a resolution of up to 30 m.

Results of the JIMO Follow-on Destinations Parametric Studies

NASA Technical Reports Server (NTRS)

Noca, Muriel A.; Hack, Kurt J.

2005-01-01

NASA's proposed Jupiter Icy Moon Orbiter (JIMO) mission currently in conceptual development is to be the first one of a series of highly capable Nuclear Electric Propulsion (NEP) science driven missions. To understand the implications of a multi-mission capability requirement on the JIMO vehicle and mission, the NASA Prometheus Program initiated a set of parametric high-level studies to be followed by a series of more in-depth studies. The JIMO potential follow-on destinations identified include a Saturn system tour, a Neptune system tour, a Kuiper Belt Objects rendezvous, an Interstellar Precursor mission, a Multiple Asteroid Sample Return and a Comet Sample Return. This paper shows that the baseline JIMO reactor and design envelop can satisfy five out of six of the follow-on destinations. Flight time to these destinations can significantly be reduced by increasing the launch energy or/and by inserting gravity assists to the heliocentric phase.

Filling in the Gaps: Xenoliths in Meteorites are Samples of "Missing" Asteroid Lithologies

NASA Technical Reports Server (NTRS)

Zolensky, Mike

2016-01-01

We know that the stones that fall to earth as meteorites are not representative of the full diversity of small solar system bodies, because of the peculiarities of the dynamical processes that send material into Earth-crossing paths [1] which result in severe selection biases. Thus, the bulk of the meteorites that fall are insufficient to understand the full range of early solar system processes. However, the situation is different for pebble- and smaller-sized objects that stream past the giant planets and asteroid belts into the inner solar system in a representative manner. Thus, micrometeorites and interplanetary dust particles have been exploited to permit study of objects that do not provide meteorites to earth. However, there is another population of materials that sample a larger range of small solar system bodies, but which have received little attention - pebble-sized foreign clasts in meteorites (also called xenoliths, dark inclusions, clasts, etc.). Unfortunately, most previous studies of these clasts have been misleading, in that these objects have simply been identified as pieces of CM or CI chondrites. In our work we have found this to be generally erroneous, and that CM and especially CI clasts are actually rather rare. We therefore test the hypothesis that these clasts sample the full range of small solar system bodies. We have located and obtained samples of clasts in 81 different meteorites, and have begun a thorough characterization of the bulk compositions, mineralogies, petrographies, and organic compositions of this unique sample set. In addition to the standard e-beam analyses, recent advances in technology now permit us to measure bulk O isotopic compositions, and major- though trace-element compositions of the sub-mm-sized discrete clasts. Detailed characterization of these clasts permit us to explore the full range of mineralogical and petrologic processes in the early solar system, including the nature of fluids in the Kuiper belt and the outer main asteroid belt, as revealed by the mineralogy of secondary phases.

Triton Hopper: Exploring Neptune's Captured Kuiper Belt Object

NASA Technical Reports Server (NTRS)

Oleson, Steve; Landis, Geoffrey

2018-01-01

Neptune's moon Triton is a fascinating object, a dynamic moon with an atmosphere, and geysers. Triton is unique in the outer solar system in that it is most likely a captured Kuiper belt object (KBO), a leftover building block of the solar system. When Voyager flew by it was the coldest body yet found in our solar system (33 degrees Kelvin) and had volcanic activity, geysers, and a thin atmosphere. It is covered in ices made from nitrogen, water, and carbon-dioxide, and shows surface deposits of tholins, organic compounds that may be precursor chemicals to the origin of life. Exploring Triton will be a challenge well beyond anything done in previous missions; but the unique environment of Triton also allows some new possibilities for mobility. We developed a conceptual design of a Triton Hopping probe that both analyzes the surface and collects it for use to propel its hops. The Hopper would land near the South Pole in 2040 where geysers have been detected. Depending the details of propulsion chosen the Hopper should be able to jump over 300 kilometers in 60 hops or less, exploring the surface and thin atmosphere on its way. This craft will autonomously carry out detailed scientific investigations on the surface, below the surface (drilling) and in the upper atmosphere to provide unprecedented knowledge of a KBO-turned moon and expanding NASA's existing capabilities in deep space planetary exploration to include Hoppers using different ices for propellant. Triton is roughly 2700 kilometers in diameter with a surface of mostly frozen nitrogen, mostly water ice crust and core of metal and rock. Its gravity is half that of Earth's Moon and its atmosphere is 170,000th of Earth's or 0.3 of Mars.The mission concept studied investigated the full surface and atmospheric phenomenon: chemical composition of surface and near subsurface materials, the thin atmosphere, volcanic and geyser activity. Measurements of all these aspects of Triton's unique environment can only be made through focused in-situ exploration with a well-instrumented craft. And this craft will be provided revolutionary mobility, nearly global, using in-situ ices as propellants. While other concepts have looked at gathering gases at Mars to propel a hopper, long periods of time are needed to gather the thin CO2 atmosphere. Several gases, mainly nitrogen are on the surface in a readily dense ice form and just need to be picked up, vaporized and used for propellant.

Discovery of two new satellites of Pluto.

PubMed

Weaver, H A; Stern, S A; Mutchler, M J; Steffl, A J; Buie, M W; Merline, W J; Spencer, J R; Young, E F; Young, L A

2006-02-23

Pluto's first known satellite, Charon, was discovered in 1978. It has a diameter (approximately 1,200 km) about half that of Pluto, which makes it larger, relative to its primary, than any other moon in the Solar System. Previous searches for other satellites around Pluto have been unsuccessful, but they were not sensitive to objects less, similar150 km in diameter and there are no fundamental reasons why Pluto should not have more satellites. Here we report the discovery of two additional moons around Pluto, provisionally designated S/2005 P 1 (hereafter P1) and S/2005 P 2 (hereafter P2), which makes Pluto the first Kuiper belt object known to have multiple satellites. These new satellites are much smaller than Charon, with estimates of P1's diameter ranging from 60 km to 165 km, depending on the surface reflectivity; P2 is about 20 per cent smaller than P1. Although definitive orbits cannot be derived, both new satellites appear to be moving in circular orbits in the same orbital plane as Charon, with orbital periods of approximately 38 days (P1) and approximately 25 days (P2).

High-precision Orbit Fitting and Uncertainty Analysis of (486958) 2014 MU69

NASA Astrophysics Data System (ADS)

Porter, Simon B.; Buie, Marc W.; Parker, Alex H.; Spencer, John R.; Benecchi, Susan; Tanga, Paolo; Verbiscer, Anne; Kavelaars, J. J.; Gwyn, Stephen D. J.; Young, Eliot F.; Weaver, H. A.; Olkin, Catherine B.; Parker, Joel W.; Stern, S. Alan

2018-07-01

NASA’s New Horizons spacecraft will conduct a close flyby of the cold-classical Kuiper Belt Object (KBO) designated (486958) 2014 MU69 on 2019 January 1. At a heliocentric distance of 44 au, “MU69” will be the most distant object ever visited by a spacecraft. To enable this flyby, we have developed an extremely high-precision orbit fitting and uncertainty processing pipeline, making maximal use of the Hubble Space Telescope’s Wide Field Camera 3 (WFC3) and pre-release versions of the ESA Gaia Data Release 2 (DR2) catalog. This pipeline also enabled successful predictions of a stellar occultation by MU69 in 2017 July. We describe how we process the WFC3 images to match the Gaia DR2 catalog, extract positional uncertainties for this extremely faint target (typically 140 photons per WFC3 exposure), and translate those uncertainties into probability distribution functions for MU69 at any given time. We also describe how we use these uncertainties to guide New Horizons, plan stellar occultions of MU69, and derive MU69's orbital evolution and long-term stability.

Modelling the inner debris disc of HR 8799

NASA Astrophysics Data System (ADS)

Contro, B.; Horner, J.; Wittenmyer, R. A.; Marshall, J. P.; Hinse, T. C.

2016-11-01

In many ways, the HR 8799 planetary system strongly resembles our own. It features four giant planets and two debris belts, analogues to the Asteroid and Edgeworth-Kuiper belts. Here, we present the results of dynamical simulations of HR8799's inner debris belt, to study its structure and collisional environment. Our results suggest that HR 8799's inner belt is highly structured, with gaps between regions of dynamical stability. The belt is likely constrained between sharp inner and outer edges, located at ˜6 and ˜8 au, respectively. Its inner edge coincides with a broad gap cleared by the 4:1 mean-motion resonance with HR 8799e. Within the belt, planetesimals are undergoing a process of collisional attrition like that observed in the Asteroid belt. However, whilst the mean collision velocity in the Asteroid belt exceeds 5 km s-1, the majority of collisions within HR 8799's inner belt occur with velocities of order 1.2 km s-1, or less. Despite this, they remain sufficiently energetic to be destructive - giving a source for the warm dust detected in the system. Interior to the inner belt, test particles remain dynamically unstirred, aside from narrow bands excited by distant high-order resonances with HR 8799e. This lack of stirring is consistent with earlier thermal modelling of HR 8799's infrared excess, which predicted little dust inside 6 au. The inner system is sufficiently stable and unstirred that the formation of telluric planets is feasible, although such planets would doubtless be subject to a punitive impact regime, given the intense collisional grinding required in the inner belt to generate the observed infrared excess.

New Opportunities for Outer Solar System Science using Radioisotope Electric Propulsion

DOE Office of Scientific and Technical Information (OSTI.GOV)

Noble, Robert J.; /SLAC; Amini, Rashied

Today, our questions and hypotheses about the Solar System's origin have surpassed our ability to deliver scientific instruments to deep space. The moons of the outer planets, the Trojan and Centaur minor planets, the trans-Neptunian objects (TNO), and distant Kuiper Belt objects (KBO) hold a wealth of information about the primordial conditions that led to the formation of our Solar System. Robotic missions to these objects are needed to make the discoveries, but the lack of deep-space propulsion is impeding this science. Radioisotope electric propulsion (REP) will revolutionize the way we do deep-space planetary science with robotic vehicles, giving themmore » unprecedented mobility. Radioisotope electric generators and lightweight ion thrusters are being developed today which will make possible REP systems with specific power in the range of 5 to 10 W/kg. Studies have shown that this specific power range is sufficient to perform fast rendezvous missions from Earth to the outer Solar System and fast sample return missions. This whitepaper discusses how mobility provided by REP opens up entirely new science opportunities for robotic missions to distant primitive bodies. We also give an overview of REP technology developments and the required next steps to realize REP.« less

The Canada-France Ecliptic Plane Survey (CFEPS)—High-latitude Component

NASA Astrophysics Data System (ADS)

Petit, J.-M.; Kavelaars, J. J.; Gladman, B. J.; Jones, R. L.; Parker, J. Wm.; Bieryla, A.; Van Laerhoven, C.; Pike, R. E.; Nicholson, P.; Ashby, M. L. N.; Lawler, S. M.

2017-05-01

The High Ecliptic Latitude (HiLat) extension of the Canada-France Ecliptic Plane Survey (CFEPS), conducted from 2006 June to 2009 July, discovered a set of Trans-Neptunian objects (TNOs) that we report here. The HiLat component was designed to address one of the shortcomings of ecliptic surveys (like CFEPS), their low sensitivity to high-inclination objects. We searched 701 deg2 of sky ranging from 12° to 85° ecliptic latitude and discovered 24 TNOs, with inclinations between 15° and 104°. This survey places a very strong constraint on the inclination distribution of the hot component of the classical Kuiper Belt, ruling out any possibility of a large intrinsic fraction of highly inclined orbits. Using the parameterization of Brown, the HiLat sample combined with CFEPS imposes a width 14° ≤ σ ≤ 15.°5, with a best match for σ = 14.°5. HiLat discovered the first retrograde TNO, 2008 KV42, with an almost polar orbit with inclination 104°, and (418993) = 2009 MS9, a scattering object with perihelion in the region of Saturn’s influence, with a ˜ 400 au and I = 68°.

Throwing Icebergs at White Dwarfs

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stephan, Alexander P.; Naoz, Smadar; Zuckerman, B., E-mail: alexpstephan@astro.ucla.edu

White dwarfs (WDs) have atmospheres that are expected to consist nearly entirely of hydrogen and helium, since heavier elements will sink out of sight on short timescales. However, observations have revealed atmospheric pollution by heavier elements in about a quarter to a half of all WDs. While most of the pollution can be accounted for with asteroidal or dwarf planetary material, recent observations indicate that larger planetary bodies, as well as icy and volatile material from Kuiper belt analog objects, are also viable sources of pollution. The commonly accepted pollution mechanisms, namely scattering interactions between planetary bodies orbiting the WDs,more » can hardly account for pollution by objects with large masses or long-period orbits. Here we report on a mechanism that naturally leads to the emergence of massive body and icy and volatile material pollution. This mechanism occurs in wide binary stellar systems, where the mass loss of the planets’ host stars during post main sequence stellar evolution can trigger the Eccentric Kozai–Lidov mechanism. This mechanism leads to large eccentricity excitations, which can bring massive and long-period objects close enough to the WDs to be accreted. We find that this mechanism readily explains and is consistent with observations.« less

An Icy Kuiper Belt Around the Young Solar-type Star HD 181327

NASA Technical Reports Server (NTRS)

Lebreton, J.; Augereau, J.-C.; Thi, W.-F.; Roberge, A.; Donaldson, J; Schneider, G.; Maddison, S. T.; Menard, F.; Riviere-Marichalar, P.; Matthews, G. S.;

Posible origen del agua terrestre

NASA Astrophysics Data System (ADS)

di Sisto, R. P.; Orellana, R. B.; Brunini, A.

The most plausible sources of the terrestrial water are found in the main external asteroid belt, the giant planetary region and in the Kuiper belt, because of its great presence of ices. However, the timing of earth planets's formation (108 years) marks an inferior limit for the dynamical lifetime of the objects of interest since the previous megaimpacts would volatilize the icy material previusly accreted. The central parameter that allow us to rebuild the origin of water in the solar system is the rate of the Deuterium/Hydrogen isotope (D/H). The D/H measured in three comets has an average value two times greater that the value measured in the terrestrial oceans. Morbidelli et al. support that the main part of the present buldge of water on earth was product of the accretion, in the last formation stages, of some planetary embryos originally formed in the external asteroid belt. In the Jupiter zone, the D/H could be of the order of the terrestrial value. Then, we would have there posible sources with an apropiate isotopic composition that have survived for several 108 years. These sources are: the Troyan asteroids, objects in the Jupiter-Saturn region and objects in the external limit of the asteroidal belt. As for this last group we have considered in this work, the Hilda Family asteroids. The Hilda Family asteroids are placed in the 3/2 mean motion resonance with Jupiter. From the present distribution of the Hilda's orbital parameters, we generate randomly, inicial conditions for 500 massless particles in the Hildas region. Trough numerical simulations we follow their dynamical evolution during 500 millon years and its final state. The mayority of these particles are eyected out of the Solar System (76 %) due to the gravitational action of Jupiter and only a 24 % stay in the resonance zone. The 8.1 % of the particles that leave the resonance, hit Jupiter. Some objects have encounters with the terrestrial planets. From the number of encounters with each planet, we obtain the number of colisions and the total mass that impact with those planets. Assuming a primordial population of 108 objects in the Hildas zone, the mass that colide with Venus, the Earth and Mars is 4.6x1016 kg., 6.9x1016 kg. y 2.4x1016 kg. respectively. The total mass of water present on Earth is 3x1020 kg., much greater than the quantity provided by the hildas. So, this population wouldn't be the main responsable for the water in the terrestrial planets.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steele, Amy; Hughes, A. Meredith; Carpenter, John

The presence of debris disks around young main-sequence stars hints at the existence and structure of planetary systems. Millimeter-wavelength observations probe large grains that trace the location of planetesimal belts. The Formation and Evolution of Planetary Systems Spitzer Legacy survey of nearby young solar analogues yielded a sample of five debris disk-hosting stars with millimeter flux suitable for interferometric follow-up. We present observations with the Submillimeter Array (SMA) and the Combined Array for Research in Millimeter-wave Astronomy at ∼2″ resolution that spatially resolve the debris disks around these nearby (d ∼ 50 pc) stars. Two of the five disks (HDmore » 377, HD 8907) are spatially resolved for the first time and one (HD 104860) is resolved at millimeter wavelengths for the first time. We combine our new observations with archival SMA and Atacama Large Millimeter/Submillimeter Array data to enable a uniform analysis of the full five-object sample. We simultaneously model the broadband photometric data and resolved millimeter visibilities to constrain the dust temperatures and disk morphologies, and perform a Markov Chain Monte Carlo analysis to fit for basic structural parameters. We find that the radii and widths of the cold outer belts exhibit properties consistent with scaled-up versions of the Solar System's Kuiper Belt. All the disks exhibit characteristic grain sizes comparable to the blowout size, and all the resolved observations of emission from large dust grains are consistent with an axisymmetric dust distribution to within the uncertainties. These results are consistent with comparable studies carried out at infrared wavelengths.« less

COLLISIONAL GROOMING MODELS OF THE KUIPER BELT DUST CLOUD

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuchner, Marc J.; Stark, Christopher C., E-mail: Marc.Kuchner@nasa.go, E-mail: starkc@umd.ed

2010-10-15

We modeled the three-dimensional structure of the Kuiper Belt (KB) dust cloud at four different dust production rates, incorporating both planet-dust interactions and grain-grain collisions using the collisional grooming algorithm. Simulated images of a model with a face-on optical depth of {approx}10{sup -4} primarily show an azimuthally symmetric ring at 40-47 AU in submillimeter and infrared wavelengths; this ring is associated with the cold classical KB. For models with lower optical depths (10{sup -6} and 10{sup -7}), synthetic infrared images show that the ring widens and a gap opens in the ring at the location of Neptune; this feature ismore » caused by trapping of dust grains in Neptune's mean motion resonances. At low optical depths, a secondary ring also appears associated with the hole cleared in the center of the disk by Saturn. Our simulations, which incorporate 25 different grain sizes, illustrate that grain-grain collisions are important in sculpting today's KB dust, and probably other aspects of the solar system dust complex; collisions erase all signs of azimuthal asymmetry from the submillimeter image of the disk at every dust level we considered. The model images switch from being dominated by resonantly trapped small grains ('transport dominated') to being dominated by the birth ring ('collision dominated') when the optical depth reaches a critical value of {tau} {approx} v/c, where v is the local Keplerian speed.« less

The Trojan-Hilda-KBO connection: An observational test of solar system evolution models

NASA Astrophysics Data System (ADS)

Wong, Ian; Brown, Michael

2017-10-01

Over the past few decades, many theories have been devised to explain the observed solar system architecture. The current paradigm posits that a significant reorganization of the outer Solar System occurred after the end of planet formation. Specifically, it is hypothesized that Jupiter and Saturn crossed a mutual mean motion resonance, leading to a chaotic expansion of the ice giants’ orbits that disrupted the large population of planetesimals situated further out. While the majority of these bodies were ejected from the Solar System, a fraction of them were retained as the present-day Kuiper Belt, while others were scattered inward and captured into resonances with Jupiter to become the Trojans and Hildas. Dynamical instability models invariably predict that Trojans, Hildas, and Kuiper Belt objects (KBOs) were sourced from the same primordial body of outer solar system planetesimals. Therefore, comparison of these minor body populations serves as one of the few available observational tests of our present understanding of solar system evolution.We present the results of a series of studies aimed at synthesizing a detailed picture of Trojans and related asteroid populations. By combining analyses of archival data with new photometric surveys, we have derived the first debiased color distributions of Trojans and KBOs and extended/refined our knowledge of their respective size distributions. In addition, we have explored the peculiar color bimodality attested in the Trojans, Hildas, and KBOs, which indicates the presence of two sub-populations. As part of our continuing efforts to characterize the surface composition of these bodies, we have also obtained new near-infrared spectra of Hildas for comparison with previously published spectra of Trojans covering the same wavelength region. We have utilized the full body of observations to formulate hypotheses regarding the formation, composition, and dynamical/chemical evolution of the primordial outer solar system planetesimals, with special attention given to explaining the color bimodality and size distribution shapes. Our results lay the groundwork for future studies with next-generation instruments and ultimately, the Trojan flyby mission Lucy.

New Horizons: Bridge to the Beginning - to Pluto and Beyond

NASA Astrophysics Data System (ADS)

Weir, H. M.; Hallau, K. G.; Seaton, P.; Beisser, K.; New Horizons Education; Public Outreach Team

2010-12-01

Launched on Jan. 19, 2006, NASA’s New Horizons mission to Pluto and the Kuiper Belt will help us understand worlds at the edge of our solar system by making the first reconnaissance of Pluto and Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. However, New Horizons’ closest approach to Pluto will not occur until July 14, 2015, and the majority of the craft's time over the next 5 years will be spent in "hibernation." The Education and Public Outreach (EPO) team, however, will not be hibernating as we wait for New Horizons to reach its destination. With three distinct tools-- Educator Fellows, online learning modules and a planetarium program--the team seeks to excite and engage teachers, students and the public with information about the journey to Pluto and beyond. In the past year, the specially selected educators who participate as New Horizons Educator Fellows have trained more than 1,000 teachers across the U.S. on the New Horizons mission and the science behind it. Thousands more students, parents, educators, and citizens have learned about New Horizons from the mission's scientists, engineers and outreach professionals. New Horizons Fellows also distribute another EPO tool: online learning modules. These classroom-ready learning modules consist of educator guides, student handouts, detailed activities, and potential adaptations for students with special needs or disabilities. Some also offer online interactives to convey complex and dynamic concepts. The modules are web-accessible for both students and teachers, and are aligned with relevant national standards. The third tool is a highly visual way to engage the general public and supplement educational programs: a planetarium program that highlights the New Horizons mission from launch to destination Pluto. This program focuses on the engineering design of the spacecraft, with a focus on the concept of the electromagnetic spectrum. In the unique environment of the planetarium, users identify and view celestial objects at multiple wavelengths of light and discover how the instruments collect such data, which will help answer questions about Pluto, its moons, and the Kuiper Belt. The program is designed for educators and students at the middle school level and above.

The Trojan-Hilda-KBO connection: An observational test of solar system evolution models

NASA Astrophysics Data System (ADS)

Wong, I.; Brown, M. E.

2017-12-01

Over the past few decades, many theories have been devised to explain the observed solar system architecture. The current paradigm posits that a significant reorganization of the outer Solar System occurred after the end of planet formation. Specifically, it is hypothesized that Jupiter and Saturn crossed a mutual mean motion resonance, leading to a chaotic expansion of the ice giants' orbits that disrupted the large population of planetesimals situated further out. While the majority of these bodies were ejected from the Solar System, a fraction of them were retained as the present-day Kuiper Belt, while others were scattered inward and captured into resonances with Jupiter to become the Trojans and Hildas. Dynamical instability models invariably predict that Trojans, Hildas, and Kuiper Belt objects (KBOs) were sourced from the same primordial body of outer solar system planetesimals. Therefore, comparison of these minor body populations serves as one of the few available observational tests of our present understanding of solar system evolution. We present the results of a series of studies aimed at synthesizing a detailed picture of Trojans and related asteroid populations. By combining analyses of archival data with new photometric surveys, we have derived the first debiased color distributions of Trojans and KBOs and extended/refined our knowledge of their respective size distributions. In addition, we have explored the peculiar color bimodality attested in the Trojans, Hildas, and KBOs, which indicates the presence of two sub-populations. As part of our continuing efforts to characterize the surface composition of these bodies, we have also obtained new near-infrared spectra of Hildas for comparison with previously published spectra of Trojans covering the same wavelength region. We have utilized the full body of observations to formulate hypotheses regarding the formation, composition, and dynamical/chemical evolution of the primordial outer solar system planetesimals, with special attention given to explaining the color bimodality and size distribution shapes. Our results lay the groundwork for future studies with next-generation instruments and ultimately, the Trojan flyby mission Lucy.

Oxygen isotopic composition of chondritic interplanetary dust particles: A genetic link between carbonaceous chondrites and comets

NASA Astrophysics Data System (ADS)

Aléon, J.; Engrand, C.; Leshin, L. A.; McKeegan, K. D.

2009-08-01

Oxygen isotopes were measured in four chondritic hydrated interplanetary dust particles (IDPs) and five chondritic anhydrous IDPs including two GEMS-rich particles (Glass embedded with metal and sulfides) by a combination of high precision and high lateral resolution ion microprobe techniques. All IDPs have isotopic compositions tightly clustered around that of solar system planetary materials. Hydrated IDPs have mass-fractionated oxygen isotopic compositions similar to those of CI and CM carbonaceous chondrites, consistent with hydration of initially anhydrous protosolar dust. Anhydrous IDPs have small 16O excesses and depletions similar to those of carbonaceous chondrites, the largest 16O variations being hosted by the two GEMS-rich IDPs. Coarse-grained forsteritic olivine and enstatite in anhydrous IDPs are isotopically similar to their counterparts in comet Wild 2 and in chondrules suggesting a high temperature inner solar system origin. The small variations in the 16O content of GEMS-rich IDPs suggest that most GEMS either do not preserve a record of interstellar processes or the initial interstellar dust is not 16O-rich as expected by self-shielding models, although a larger dataset is required to verify these conclusions. Together with other chemical and mineralogical indicators, O isotopes show that the parent-bodies of carbonaceous chondrites, of chondritic IDPs, of most Antarctic micrometeorites, and comet Wild 2 belong to a single family of objects of carbonaceous chondrite chemical affinity as distinct from ordinary, enstatite, K- and R-chondrites. Comparison with astronomical observations thus suggests a chemical continuum of objects including main belt and outer solar system asteroids such as C-type, P-type and D-type asteroids, Trojans and Centaurs as well as short-period comets and other Kuiper Belt Objects.

Rotational breakup as the origin of small binary asteroids.

PubMed

Walsh, Kevin J; Richardson, Derek C; Michel, Patrick

2008-07-10

Asteroids with satellites are observed throughout the Solar System, from subkilometre near-Earth asteroid pairs to systems of large and distant bodies in the Kuiper belt. The smallest and closest systems are found among the near-Earth and small inner main-belt asteroids, which typically have rapidly rotating primaries and close secondaries on circular orbits. About 15 per cent of near-Earth and main-belt asteroids with diameters under 10 km have satellites. The mechanism that forms such similar binaries in these two dynamically different populations was hitherto unclear. Here we show that these binaries are created by the slow spinup of a 'rubble pile' asteroid by means of the thermal YORP (Yarkovsky-O'Keefe-Radzievskii-Paddack) effect. We find that mass shed from the equator of a critically spinning body accretes into a satellite if the material is collisionally dissipative and the primary maintains a low equatorial elongation. The satellite forms mostly from material originating near the primary's surface and enters into a close, low-eccentricity orbit. The properties of binaries produced by our model match those currently observed in the small near-Earth and main-belt asteroid populations, including 1999 KW(4) (refs 3, 4).

Rotational breakup as the origin of small binary asteroids

NASA Astrophysics Data System (ADS)

Walsh, Kevin J.; Richardson, Derek C.; Michel, Patrick

2008-07-01

Asteroids with satellites are observed throughout the Solar System, from subkilometre near-Earth asteroid pairs to systems of large and distant bodies in the Kuiper belt. The smallest and closest systems are found among the near-Earth and small inner main-belt asteroids, which typically have rapidly rotating primaries and close secondaries on circular orbits. About 15 per cent of near-Earth and main-belt asteroids with diameters under 10km have satellites. The mechanism that forms such similar binaries in these two dynamically different populations was hitherto unclear. Here we show that these binaries are created by the slow spinup of a `rubble pile' asteroid by means of the thermal YORP (Yarkovsky-O'Keefe-Radzievskii-Paddack) effect. We find that mass shed from the equator of a critically spinning body accretes into a satellite if the material is collisionally dissipative and the primary maintains a low equatorial elongation. The satellite forms mostly from material originating near the primary's surface and enters into a close, low-eccentricity orbit. The properties of binaries produced by our model match those currently observed in the small near-Earth and main-belt asteroid populations, including 1999KW4 (refs 3, 4).

Measuring the Yarkovsky effect with Las Cumbres Observatory

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Farnocchia, Davide; Lister, Tim

2017-10-01

The Las Cumbres Observatory (LCO) provides an ideal platform for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects) and ultimately for the discovery of new objects. We have used LCO's global network of nine 1-meter telescopes to measure the Yarkovsky effect on tens of asteroids through precise astrometric measurements using the Gaia-DR1 catalog, providing lower uncertainty with each detection. The target asteroids were picked through simulated observations each month to determine the objects for which new astrometry would yield the most improvement. The Gaia-DR1 release has greatly improved the quality of the astrometry obtained, making the detection of the Yarkovsky effect more likely and secure by greatly reducing systematic catalog zonal errors. With the release of DR2 next year and the availability of good reference star colors, we will be able to take other more subtle effects into account in the astrometric reduction. In addition, the availability of the Gaia catalog would allow re-measurement of past data with more accurate star catalogs. The amount of Yarkovsky acceleration depends on several physical properties, such as the asteroid spin state, size, mass, and thermal properties, to which detection of the effect can give important constraints. The effect is also important for understanding the transportation of asteroids and meteorites into near-Earth space from the main belt, producing the NEOs and for the formation and evolution of asteroid families. Determining and modeling the Yarkovsky effect can be critical for accurate prediction of asteroid trajectories and even for impact hazard assessment. The measurements made with the help of LCO have significantly increased the number of known asteroids with Yarkovsky detections. LCO is ideally suited to perform these observations due to its ability to monitor several targets over several days by employing dynamic scheduling, weather avoidance, and use of multiple sites around the globe.

The Extraordinary Albedo Variations on Pluto Detected by New Horizons and Implications for Dwarf Planet Eris

NASA Astrophysics Data System (ADS)

Buratti, Bonnie J.; Hofgartner, Jason D.; Stern, S. Alan; Weaver, Harold A.; Verbiscer, Anne J.; Ennico, Kimberly; Olkin, Catherine B.; Young, Leslie; New Horizons Geology and Geophysics Team

2016-10-01

The New Horizons mission returned stunning observations of active geology on the surface of Pluto (Stern et al., 2015, Science 350, 292). One of the markers for activity on planets or moons is normal albedos approaching 1.0, as is the case for Enceladus (Buratti et al., 1984, Icarus 58, 254; Verbiscer et al., 2005, Icarus 173, 66). When all corrections for viewing geometry are made for Pluto, it has normal albedos that approach unity in the regions that show evidence for activity by a lack of craters, notably the region informally named Sputnik Planum. On the other hand, Pluto also has a very dark (normal albedo ~0.10) equatorial belt.The geometric albedo of Eris, another large dwarf planet in the Kuiper Belt, is 0.96 (Sicardy et al., 2011, Nature 478, 493), close to that of Enceladus. Coupled with a high density of 2.5 gm/cc (Sicardy et al., ibid.), implying an even larger amount of radiogenic heating than that for Pluto (with a density near 1.9 gm/cc), we find it highly likely that Eris is also active with some type of solid state convection or cryovolcanism on its surface. Alternate explanations such as complete condensation of methane frost onto its surface in the colder environment at nearly 100 AUs would not lead to the high albedo observed.Another implication of the extreme albedo variations on Pluto is that the temperature varies by at least 20K on its surface, spawning possible aeolian processes and associated features such as wind streaks and dunes, which are currently being sought on New Horizons images. Finally, low albedo regions on Pluto, with normal reflectances less than 0.10, provide possible evidence for dust in the Kuiper Belt that is accreting onto the surface of Pluto. Another - or additional - explanation for this low-albedo dust is native material created in Pluto's hazy atmosphere.New Horizons funding by NASA is gratefully acknowledged.

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

An audience member asks the panelists a question at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. Scientists discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

OSSOS. II. A SHARP TRANSITION IN THE ABSOLUTE MAGNITUDE DISTRIBUTION OF THE KUIPER BELT’S SCATTERING POPULATION

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shankman, C.; Kavelaars, JJ.; Bannister, M. T.

We measure the absolute magnitude, H, distribution, dN(H) ∝ 10{sup αH}, of the scattering Trans-Neptunian Objects (TNOs) as a proxy for their size-frequency distribution. We show that the H-distribution of the scattering TNOs is not consistent with a single-slope distribution, but must transition around H{sub g} ∼ 9 to either a knee with a shallow slope or to a divot, which is a differential drop followed by second exponential distribution. Our analysis is based on a sample of 22 scattering TNOs drawn from three different TNO surveys—the Canada–France Ecliptic Plane Survey, Alexandersen et al., and the Outer Solar System Origins Survey, all of whichmore » provide well-characterized detection thresholds—combined with a cosmogonic model for the formation of the scattering TNO population. Our measured absolute magnitude distribution result is independent of the choice of cosmogonic model. Based on our analysis, we estimate that the number of scattering TNOs is (2.4–8.3) × 10{sup 5} for H{sub r} < 12. A divot H-distribution is seen in a variety of formation scenarios and may explain several puzzles in Kuiper Belt science. We find that a divot H-distribution simultaneously explains the observed scattering TNO, Neptune Trojan, Plutino, and Centaur H-distributions while simultaneously predicting a large enough scattering TNO population to act as the sole supply of the Jupiter-Family Comets.« less

Comportamiento dinámico de asteroides en la región 23 < a < 26 UA

NASA Astrophysics Data System (ADS)

López García, F.

Los Kuiper Belt Objects (KBOs) pueden ser una fuente de origen de los cometas de corto período. Muchos de los KBOs observados parecen provenir, al igual que el sistema Pluton-Charonte, de órbitas resonantes con Neptuno. Los Centauros son objetos que dinámicamente provienen de órbitas inestables cuyo semieje mayor se encuentra entre las órbitas de Júpiter y Neptuno. Pudiera ser que estos cuerpos fueron expulsados desde la región del cinturón de Kuiper y se encuentran en un proceso de ``scattering" debido a los efectos gravitacionales de los planetas gigantes. Su tiempo de vida dinámico es de algunos millones de años. La evolución orbital de los objetos trans-Neptunianos nos permite conocer su comportamiento anterior, por eso, es importante su relación dinámica con la evolución orbital de Neptuno. El objeto de este trabajo es estudiar el comportamiento dinámico de partículas test que se encuentran entre las resonancias 3:2 con Neptuno y 2:3 con Urano, las cuales comprenden una región de 2 UA aproximadamente. Los primeros resultados indican que la mayoría de los objetos ficticios son eyectados hacia la parte externa del Sistema Solar, mientras que sólo una parte pequeña del total de objetos estudiados, aproximadamente un 7%, son eyectados hacia la parte interna del Sistema Solar, y en algunos casos sus órbitas pueden cruzar la órbita de los planetas terrestres.

KSC-05pd2273

NASA Image and Video Library

2005-09-29

KENNEDY SPACE CENTER, FLA. - On the Shuttle Landing Facility at NASA Kennedy Space Center, the Atlas V fairing halves for the New Horizons spacecraft have been offloaded from the Russian cargo plane (background). The fairing halves will be transported to Astrotech Space Operations in Titusville. The fairing later will be placed around the New Horizons spacecraft in the Payload Hazardous Service Facility. A fairing protects a spacecraft during launch and flight through the atmosphere. Once in space, it is jettisoned. The Lockheed Martin Atlas V is the launch vehicle for the New Horizons spacecraft, which is designed to make the first reconnaissance of Pluto and Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and its moon, Charon, in July 2015.

KSC-05pd2274

NASA Image and Video Library

2005-09-29

KENNEDY SPACE CENTER, FLA. - On the Shuttle Landing Facility at NASA Kennedy Space Center, one of the Atlas V fairing halves for the New Horizons spacecraft is offloaded from the Russian cargo plane. The fairing halves will be transported to Astrotech Space Operations in Titusville. The fairing later will be placed around the New Horizons spacecraft in the Payload Hazardous Service Facility. A fairing protects a spacecraft during launch and flight through the atmosphere. Once in space, it is jettisoned. The Lockheed Martin Atlas V is the launch vehicle for the New Horizons spacecraft, which is designed to make the first reconnaissance of Pluto and Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and its moon, Charon, in July 2015.

Phase Curves of Nix and Hydra from the New Horizons Imaging Cameras

NASA Astrophysics Data System (ADS)

Verbiscer, Anne J.; Porter, Simon B.; Buratti, Bonnie J.; Weaver, Harold A.; Spencer, John R.; Showalter, Mark R.; Buie, Marc W.; Hofgartner, Jason D.; Hicks, Michael D.; Ennico-Smith, Kimberly; Olkin, Catherine B.; Stern, S. Alan; Young, Leslie A.; Cheng, Andrew; (The New Horizons Team

2018-01-01

NASA’s New Horizons spacecraft’s voyage through the Pluto system centered on 2015 July 14 provided images of Pluto’s small satellites Nix and Hydra at viewing angles unattainable from Earth. Here, we present solar phase curves of the two largest of Pluto’s small moons, Nix and Hydra, observed by the New Horizons LOng Range Reconnaissance Imager and Multi-spectral Visible Imaging Camera, which reveal the scattering properties of their icy surfaces in visible light. Construction of these solar phase curves enables comparisons between the photometric properties of Pluto’s small moons and those of other icy satellites in the outer solar system. Nix and Hydra have higher visible albedos than those of other resonant Kuiper Belt objects and irregular satellites of the giant planets, but not as high as small satellites of Saturn interior to Titan. Both Nix and Hydra appear to scatter visible light preferentially in the forward direction, unlike most icy satellites in the outer solar system, which are typically backscattering.

Status of the Transneptunian Automated Occultation Survey (TAOS II)

NASA Astrophysics Data System (ADS)

Lehner, Matthew; Wang, Shiang-Yu; Reyes-Ruiz, Mauricio; Alcock, Charles; Castro Chacón, Joel; Chen, Wen-Ping; Chu, You-Hua; Cook, Kem H.; Figueroa, Liliana; Geary, John C.; Hernandez, Benjamin; Huang, Chung-Kai; Norton, Timothy; Szentgyorgyi, Andrew; Yen, Wei-Ling; Zhang, Zhi-Wei

2017-10-01

The Transneptunian Automated Occultation Survey (TAOS II) will aim to detect occultations of stars by small (~1 km diameter) objects in the Kuiper Belt and beyond. Such events are very rare (<0.001 events per star per year) and short in duration (~200 ms), so many stars must be monitored at a high readout cadence. TAOS II will operate three 1.3 meter telescopes at the Observatorio Astronómico Nacional at San Pedro Mártir in Baja California, México. With a 2.3 square degree field of view and a high speed camera comprising CMOS imagers, the survey will monitor 10,000 stars simultaneously with all three telescopes at a readout cadence of 20 Hz. Construction of the site began in the fall of 2013 and was completed this summer. Telescope installation began in August 2017. This poster will provide an update on the status of the survey development and the schedule leading to the beginning of survey operations.

Search for water and life's building blocks in the Universe

NASA Astrophysics Data System (ADS)

Kwok, Sun; Bergin, Edwin; Ehrenfreund, Pascale

Water is the common ground between astronomy and planetary science as the presence of water on a planet is universally accepted as essential for its potential habitability. Water assists many biological chemical reactions leading to complexity by acting as an effective solvent. It shapes the geology and climate on rocky planets, and is a major or primary constituent of the solid bodies of the outer solar system. Water ice seems universal in space and is by far the most abundant condensed-phase species in our universe. Water-rich icy layers cover dust particles within the cold regions of the interstellar medium and molecular ices are widespread in the solar system. The poles of terrestrial planets (e.g. Earth, Mars) and most of the outer-solar-system satellites are covered with ice. Smaller solar system bodies, such as comets and Kuiper Belt Objects (KBOs), contain a significant fraction of water ice and trace amounts of organics. Beneath the ice crust of several moons of Jupiter and Saturn liquid water oceans probably exist.

The Investigations of Orbital Evolution of Centaurs 2060 Chiron, P/Oterma and P/Schwassmann-Wachmann 1

NASA Astrophysics Data System (ADS)

Kovalenko, N.; Churyumov, K.; Babenko, Yu.

2002-01-01

Chiron, comet 39P/Oterma and comet 29P/Schwassmann-Wachmann 1 are discussed. The orbital evolutions of chosen objects were traced 1 million years backward and forward from the present time. For numerical integration the program based on the Everhart implicit single sequence methods for integrating orbits was used. perturbations from the giant planets and very chaotic. It is now believed that Centaurs could be captured from the Kuiper Belt and in the future transform into the short-period comets. Currently more then 20 Centaurs are known. The cometary activity in one of them (2060 Chiron) has been detected up to now. simulated the past and future orbital evolution of active Centaur 2060 (95P) Chiron and two distant Jupiter-family comets with similar to Centaurs' perihelia and aphelia - comets 39P/Oterma and 29P/Schwassmann-Wachmann 1. Only our knowledge gathered from the Earth-based observations, orbital evolution investigations and future spacecraft missions will solve this problem.

KSC-05pd2410

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2617

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - At their consoles in the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, members of the New Horizons team take part in a dress rehearsal for the launch scheduled in mid-January. Seen here (left to right) are David Kusnierkiewicz, New Horizons mission system engineer; Glen Fountain, Applied Physics Lab project manager; and Alan Stern, principal investigator from Southwest Research Institute. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2415

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, technicians prepare the New Horizons spacecraft for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2613

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - At their consoles in the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, members of the New Horizons team take part in a dress rehearsal for the launch scheduled in mid-January. From left are Lockheed Martin's Program Manager John Crocker; Michael Kubiak with the U.S. Air Force, participating with Lockheed Martin on the Education with Industry program; and Lockheed Martin's Carlos Prado. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

KSC-05pd2414

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is ready for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2411

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, technicians prepare the New Horizons spacecraft for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2413

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the New Horizons spacecraft is being prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Seen behind the spacecraft is one half of the fairing that will enclose it for launch, scheduled for January 2006. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2271

NASA Image and Video Library

2005-09-29

KENNEDY SPACE CENTER, FLA. - A Russian cargo plane sits on the Shuttle Landing Facility at NASA Kennedy Space Center with the Atlas V fairing for the New Horizons spacecraft inside. The two fairing halves will be removed, loaded onto trucks and transported to Astrotech Space Operations in Titusville. The fairing later will be placed around the New Horizons spacecraft in the Payload Hazardous Service Facility. A fairing protects a spacecraft during launch and flight through the atmosphere. Once in space, it is jettisoned. The Lockheed Martin Atlas V is the launch vehicle for the New Horizons spacecraft, which is designed to make the first reconnaissance of Pluto and Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and its moon, Charon, in July 2015.

Coordinated mineralogical and isotopic analyses of a cosmic symplectite discovered in a comet 81P/Wild 2 sample

NASA Astrophysics Data System (ADS)

Nguyen, Ann N.; Berger, Eve L.; Nakamura-Messenger, Keiko; Messenger, Scott; Keller, Lindsay P.

2017-09-01

We have discovered in a Stardust mission terminal particle a unique mineralogical assemblage of symplectically intergrown pentlandite ((Fe,Ni)9S8) and nanocrystalline maghemite (γ-Fe2O3). Mineralogically similar cosmic symplectites (COS) have only been found in the primitive carbonaceous chondrite Acfer 094 and are believed to have formed by aqueous alteration. The O and S isotopic compositions of the Wild 2 COS are indistinguishable from terrestrial values. The metal and sulfide precursors were thus oxidized by an isotopically equilibrated aqueous reservoir either inside the snow line, in the Wild 2 comet, or in a larger Kuiper Belt object. Close association of the Stardust COS with a Kool mineral assemblage (kosmochloric Ca-rich pyroxene, FeO-rich olivine, and albite) that likely originated in the solar nebula suggests the COS precursors also had a nebular origin and were transported from the inner solar system to the comet-forming region after they were altered.

The trans-neptunian object UB313 is larger than Pluto.

PubMed

Bertoldi, F; Altenhoff, W; Weiss, A; Menten, K M; Thum, C

2006-02-02

The most distant known object in the Solar System, 2003 UB313 (97 au from the Sun), was recently discovered near its aphelion. Its high eccentricity and inclination to the ecliptic plane, along with its perihelion near the orbit of Neptune, identify it as a member of the 'scattered disk'. This disk of bodies probably originates in the Kuiper belt objects, which orbit near the ecliptic plane in circular orbits between 30 and 50 au, and may include Pluto as a member. The optical brightness of 2003 UB313, if adjusted to Pluto's distance, is greater than that of Pluto, which suggested that it might be larger than Pluto. The actual size, however, could not be determined from the optical measurements because the surface reflectivity (albedo) was unknown. Here we report observations of the thermal emission of 2003 UB313 at a wavelength of 1.2 mm, which in combination with the measured optical brightness leads to a diameter of 3,000 +/- 300 +/- 100 km. Here the first error reflects measurement uncertainties, while the second derives from the unknown object orientation. This makes 2003 UB313 the largest known trans-neptunian object, even larger than Pluto (2,300 km). The albedo is 0.60 +/- 0.10 +/- 0.05, which is strikingly similar to that of Pluto, suggesting that the methane seen in the optical spectrum causes a highly reflective icy surface.

Trojan Binary Candidate: A Slow-Rotating Mission Target

NASA Astrophysics Data System (ADS)

Noll, Keith

2015-10-01

A mission to the unexplored Jupiter Trojans is explicitly called for in the Planetary Decadal and HST observations in early 2016 can influence mission plans for both Discovery and New Frontiers. We propose to observe a Trojan that will be targeted by the step-1 Discovery mission, Lucy. (11351) 1997 TS25 is a Trojan that is notable for having one of the longest known rotation periods of any small body, T=514 h. A possible cause for this long period would be the existence of a tidally locked binary similar to the already-known long-period binary Trojan, (617) Patroclus. If so, the components will be separated by 0.18 arcsec at lightcurve maximum, resolvable by WFC3. We will coordinate with groundbased observations to schedule near a maximum and thus require only a single orbit to confidently test whether (11351) 1997 TS25 is binary. Binary Trojans offer scientific benefits beyond the impact to any specific mission. Orbit-derived mass and density can be used to constrain planetary migration models. Low density is characteristic of bodies found in the dynamically cold Kuiper Belt, a remnant of the solar system's protoplanetary disk. Only one undisputed density has been measured in the Trojans, that of the binary (617) Patroclus, which has a low density of 0.8 g/cm3, similar to the low densities found in the Kuiper Belt. Evidence for or against a possible common origin linking Trojans and KBOs is a key constraint for planetesimal formation and planetary migration models relevant to the solar system and to planetary systems in general.

Roles of Clathrate Hydrates in Crustal Heating and Volatile Storage/Release on Earth, Mars, and Beyond

NASA Astrophysics Data System (ADS)

Kargel, J. S.; Beget, J.; Furfaro, R.; Prieto-Ballesteros, O.; Palmero-Rodriguez, J. A.

2007-12-01

Clathrate hydrates are stable through much of the Solar System. These materials and hydrate-like amorphous associations of water with N2, CO, CH4, CO2, O2 and other molecules could, in fact, constitute the bulk of the non-rock components of some icy satellites, comets, and Kuiper Belt Objects. CO2 clathrate is thermodynamically stable at the Martian South Pole surface and could form a significant fraction of both Martian polar caps and icy permafrost distributed across one-third of the Martian surface. CH4 clathrate is the largest clathrate material in Earth's permafrost and cold seafloor regions, and it may be a major volatile reservoir on Mars, too. CO2 clathrate is less abundant on Earth but it might store most of Mars' CO2 inventory and thus may be one of the critical components in the climate system of that planet, just as CH4 clathrate is for Earth. These ice-like phases not only store biologically, geologically, and climatologically important gases, but they also are natural thermal insulators. Thus, they retard the conductive flow of geothermal heat, and thick accumulations of them can modify geotherms, cause brines to exist where otherwise they would not, and induce low-grade metamorphism of upper crustal rocks underlying the insulating bodies. This mechanism of crustal heating may be especially important in assisting hydrogeologic activity on Mars, gas-rich carbonaceous asteroids, icy satellites, and Kuiper Belt Objects. These worlds, compared to Earth, are comparatively energy starved and frozen but may partly make up for their deficit of joules by having large accumulations of joule-conserving hydrates. Thick, continuous layers of clathrate may seal in gases and produce high gas fugacities in aquifers underlying the clathrates, thus producing gas-rich reservoirs capable of erupting violently. This may have happened repeatedly in Earth history, with global climatic consequences for abrupt climate change. We have hypothesized that such eruptions may have occurred during interglacial epochs and formed super-size maar craters in Bering Land Bridge National Preserve (Alaska). On Mars, clathrates and gas-saturated aquifers apparently played some role in the largest flood- and debris-flow-forming events in that planet's history, with vast consequences for landform development and resurfacing. This heating phenomenon also has possible implications for carbon sequestration as a means of climate change mediation on Earth; besides other concerns about their long-term stability, artificial hydrates produced by carbon dioxide pumping onto the seafloor might heat up and become unstable over time due to normal background radiogenic heat flux.

X makes nine: a distant ice giant in the solar system.

PubMed

van den Berg, Hugo A

2016-06-01

Ever since Pluto lost its status as one of the main planets of our solar system and was demoted to just another frozen denizen of the Kuiper belt, we have had to make do with eight, albeit in a pleasing symmetry, with four rocky ones this side of the asteroid belt and four giants on the far side. Now it looks like number nine is back on the slate: the existence of a large planet, about ten times as massive as Earth and hundreds of times more distant from the Sun than Earth itself, has been postulated to explain the curiously bunched-up orbits of several small celestial bodies, far beyond the orbit of Neptune. To date, we have only "proof by simulation" and we are yet to observe this massive planet in the backyard of our solar system by more direct means. However, powerful new telescopes should provide visual evidence within the next few decades.

Alignment in star-debris disc systems seen by Herschel

NASA Astrophysics Data System (ADS)

Greaves, J. S.; Kennedy, G. M.; Thureau, N.; Eiroa, C.; Marshall, J. P.; Maldonado, J.; Matthews, B. C.; Olofsson, G.; Barlow, M. J.; Moro-Martín, A.; Sibthorpe, B.; Absil, O.; Ardila, D. R.; Booth, M.; Broekhoven-Fiene, H.; Brown, D. J. A.; Cameron, A. Collier; del Burgo, C.; Di Francesco, J.; Eislöffel, J.; Duchêne, G.; Ertel, S.; Holland, W. S.; Horner, J.; Kalas, P.; Kavelaars, J. J.; Lestrade, J.-F.; Vican, L.; Wilner, D. J.; Wolf, S.; Wyatt, M. C.

2014-02-01

Many nearby main-sequence stars have been searched for debris using the far-infrared Herschel satellite, within the DEBRIS, DUNES and Guaranteed-Time Key Projects. We discuss here 11 stars of spectral types A-M where the stellar inclination is known and can be compared to that of the spatially resolved dust belts. The discs are found to be well aligned with the stellar equators, as in the case of the Sun's Kuiper belt, and unlike many close-in planets seen in transit surveys. The ensemble of stars here can be fitted with a star-disc tilt of ≲ 10°. These results suggest that proposed mechanisms for tilting the star or disc in fact operate rarely. A few systems also host imaged planets, whose orbits at tens of au are aligned with the debris discs, contrary to what might be expected in models where external perturbers induce tilts.

The Canada–France Ecliptic Plane Survey (CFEPS)—High-latitude Component

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petit, J-M.; Kavelaars, J. J.; Gladman, B. J.

The High Ecliptic Latitude (HiLat) extension of the Canada–France Ecliptic Plane Survey (CFEPS), conducted from 2006 June to 2009 July, discovered a set of Trans-Neptunian objects (TNOs) that we report here. The HiLat component was designed to address one of the shortcomings of ecliptic surveys (like CFEPS), their low sensitivity to high-inclination objects. We searched 701 deg{sup 2} of sky ranging from 12° to 85° ecliptic latitude and discovered 24 TNOs, with inclinations between 15° and 104°. This survey places a very strong constraint on the inclination distribution of the hot component of the classical Kuiper Belt, ruling out any possibilitymore » of a large intrinsic fraction of highly inclined orbits. Using the parameterization of Brown, the HiLat sample combined with CFEPS imposes a width 14° ≤  σ  ≤ 15.°5, with a best match for σ  = 14.°5. HiLat discovered the first retrograde TNO, 2008 KV{sub 42}, with an almost polar orbit with inclination 104°, and (418993) = 2009 MS{sub 9}, a scattering object with perihelion in the region of Saturn’s influence, with a  ∼ 400 au and i  = 68°.« less

The Origin of Pluto's Orbit: Implications for the Solar System Beyond Neptune

NASA Technical Reports Server (NTRS)

Malhotra, Renu

1995-01-01

The origin of the highly eccentric, inclined, and resonance-locked orbit of Pluto has long been a puzzle. A possible explanation has been proposed recently which suggests that these extraordinary orbital properties may be a natural consequence of the formation and early dynamical evolution of the outer solar system. A resonance capture mechanism is possible during the clearing of the residual planetesimal debris and the formation of the Oort Cloud of comets by planetesimal mass loss from the vicinity of the giant planets. If this mechanism were in operation during the early history of the planetary system, the entire region between the orbit of Neptune and approximately 50 AU would have been swept by first-order mean motion resonances. Thus, resonance capture could occur not only for Pluto, but quite generally for other trans-Neptunian small bodies. Some consequences of this evolution for the present-day dynamical structure of the trans-Neptunian region are (1) most of the objects in the region beyond Neptune and up to approximately 50 AU exist in very narrow zones located at orbital resonances with Neptune (particularly the 3:2 and the 2:1 resonances); and (2) these resonant objects would have significantly large eccentricities. The distribution of objects in the Kuiper Belt as predicted by this theory is presented here.

On the Detectability of Planet X with LSST

NASA Astrophysics Data System (ADS)

Trilling, David E.; Bellm, Eric C.; Malhotra, Renu

2018-06-01

Two planetary mass objects in the far outer solar system—collectively referred to here as Planet X— have recently been hypothesized to explain the orbital distribution of distant Kuiper Belt Objects. Neither planet is thought to be exceptionally faint, but the sky locations of these putative planets are poorly constrained. Therefore, a wide area survey is needed to detect these possible planets. The Large Synoptic Survey Telescope (LSST) will carry out an unbiased, large area (around 18000 deg2), deep (limiting magnitude of individual frames of 24.5) survey (the “wide-fast-deep (WFD)” survey) of the southern sky beginning in 2022, and it will therefore be an important tool in searching for these hypothesized planets. Here, we explore the effectiveness of LSST as a search platform for these possible planets. Assuming the current baseline cadence (which includes the WFD survey plus additional coverage), we estimate that LSST will confidently detect or rule out the existence of Planet X in 61% of the entire sky. At orbital distances up to ∼75 au, Planet X could simply be found in the normal nightly moving object processing; at larger distances, it will require custom data processing. We also discuss the implications of a nondetection of Planet X in LSST data.

Utilizing a scale model solar system project to visualize important planetary science concepts and develop technology and spatial reasoning skills

NASA Astrophysics Data System (ADS)

Kortenkamp, Stephen J.; Brock, Laci

2016-10-01

Scale model solar systems have been used for centuries to help educate young students and the public about the vastness of space and the relative sizes of objects. We have adapted the classic scale model solar system activity into a student-driven project for an undergraduate general education astronomy course at the University of Arizona. Students are challenged to construct and use their three dimensional models to demonstrate an understanding of numerous concepts in planetary science, including: 1) planetary obliquities, eccentricities, inclinations; 2) phases and eclipses; 3) planetary transits; 4) asteroid sizes, numbers, and distributions; 5) giant planet satellite and ring systems; 6) the Pluto system and Kuiper belt; 7) the extent of space travel by humans and robotic spacecraft; 8) the diversity of extrasolar planetary systems. Secondary objectives of the project allow students to develop better spatial reasoning skills and gain familiarity with technology such as Excel formulas, smart-phone photography, and audio/video editing.During our presentation we will distribute a formal description of the project and discuss our expectations of the students as well as present selected highlights from preliminary submissions.

Oral Histories in Meteoritics and Planetary Science - XX: Dale Cruikshank

NASA Astrophysics Data System (ADS)

Sears, Derek W. G.

2013-04-01

In this interview, Dale Cruikshank (Fig. 1) explains how as an undergraduate at Iowa State University he was a summer student at Yerkes Observatory where he assisted Gerard Kuiper in work on his Photographic Lunar Atlas. Upon completing his degree, Dale went to graduate school at the University of Arizona with Kuiper where he worked on the IR spectroscopy of the lunar surface. After an eventful 1968 trip to Moscow via Prague, during which the Soviets invaded Czechoslovakia, Dale assumed a postdoc position with Vasili Moroz at the Sternberg Astronomical Institute and more observational IR astronomy. Upon returning to the United States and after a year at Arizona, Dale assumed a position at the University of Hawai'i that he held for 17 years. During this period Dale worked with others on thermal infrared determinations of the albedos of small bodies beyond the asteroid Main Belt, leading to the recognition that low-albedo material is prevalent in the outer solar system that made the first report of complex organic solids on a planetary body (Saturn's satellite Iapetus). After moving to Ames Research Center, where he works currently, he continued this work and became involved in many outer solar system missions. Dale has served the community through his involvement in developing national policies for science-driven planetary exploration, being chair of the DPS 1990-1991 and secretary/treasurer for 1982-1985. He served as president of Commission 16 (Physics of Planets) of the IAU (2001-2003). He received the Kuiper prize in 2006.

[Stellar Occultation Studies of Small Bodies in the Outer Solar System: Accomplishments, Status, and Plans

NASA Technical Reports Server (NTRS)

Elliott, James

2005-01-01

Bodies residing in the outer solar system exhibit unique physical processes, and some of the lessons learned from them can be applied to understanding what occurred in the outer solar system during its formation and early evolution. Pluto, the largest known Kuiper Belt object (KBO), and its near twin Triton--an ex-KBO that has been captured by Neptune--have nitrogen atmospheres that are in vapor-pressure equilibrium with surface ice. These atmospheres are most sensitively probed from Earth by the technique of Stellar occultations, which can provide the temperature and pressure profiles of these atmospheres at a spatial resolution of a few kilometers. Recent results from occultations show that the surface pressure of Triton's atmosphere has been increasing and that the shape of the atmosphere deviates from its expected spherical figure. With the occultation technique we can also learn the sizes of smaller bodies that have formed in the outer solar system: Charon, the Centaurs, and KBOs. Our proposed program involves identifying occultation candidates, predicting occultations, observing occultations, analysis of the data, and synthesis of the occultation results with other data. The main goals for our proposed work are to (i) further observe occultations by Triton with the objectives of understanding its pressure changes, distortion, and enigmatic thermal structure (ii) determine whether the abrupt drop in Pluto's stellar occultation light curve is caused by a sharp thermal gradient near its surface or by atmospheric haze, (iii) further observations to characterize the potential collapse of Pluto's atmosphere as it recedes from the sun (information that should be of interest to the Pluto-Kuiper Express), ( iv ) determine Charon's radius more accurately than can be done with the mutual events to derive a better estimate of Charon's density, and ( v ) directly determine the size (and albedo) of Centaurs with the goal of more accurately estimating the sizes of KBOS.

Portable Telescopic Observations of the 3 June 2017 Stellar Occultation by New Horizons Kuiper Extended Mission Target (486958) 2014 MU69

NASA Astrophysics Data System (ADS)

Verbiscer, Anne J.; Buie, Marc W.; Porter, Simon Bernard; Tamblyn, Peter; Terrell, Dirk; Benecchi, Susan; Parker, Alex; Soto, Alejandro; Wasserman, Lawrence H.; Young, Eliot F.; Zangari, Amanda Marie; New Horizons MU69 Occultation Team

2017-10-01

The New Horizons spacecraft will encounter the cold classical Kuiper Belt Object (486958) 2014 MU69 on 1 January 2019. Because it is extremely faint (V mag ~27), MU69 has only been directly observed by the Hubble Space Telescope since its discovery (by HST) in 2014 (Spencer et al. 2015 EPSC 10, 417S). Current knowledge of the physical properties of MU69 is therefore limited to its red color (F606W-F814W = 0.99 ± 0.18, Benecchi et al. 2017) and a crude estimate on its size (20-40 km) based on association with other cold classical KBO visible albedos (0.04-0.15). Stellar occultations are powerful tools with which to measure the size and shape of objects whose distance and faintness precludes any spatially resolved observations. Here we report the results of a stellar occultation of a g’=15.33 magnitude star by MU69 on 3 June 2017. The shadow path crossed both southern Africa and South America. We deployed 12 portable telescopes from Mendoza, Argentina and 13 portable telescopes from Clanwilliam, Western Cape, South Africa. Although 24 of these 25 telescopes successfully observed the occultation star at the predicted event time, no solid body detection appeared in any of the acquired lightcurves. Following the successful detection of MU69 by stellar occultation on 17 July 2017, revised predictions of the location of the shadow path on 3 June now allow the lightcurves obtained on 3 June to place important constraints on the environment surrounding MU69 as well as upper limits on the size of any small satellites in the regions probed. This work would not have been possible without the financial support of NASA, the New Horizons Project, the astrometric support of the Gaia mission, and logistical support from the South African Astronomical Observatory, the US Embassies in Buenos Aires and Pretoria and the US Consulate in Cape Town.

Jupiter - Friend or Foe?

NASA Astrophysics Data System (ADS)

Horner, J.; Jones, B. W.

2008-09-01

It has long been believed that the planet Jupiter has played a beneficial role in the development of life on the Earth, acting as a shield from objects which would otherwise go on to significantly raise the impact flux experienced by our planet. Without Jupiter, the story goes, the Earth would have experienced a far greater number of impacts, making it far less hospitable to burgeoning life. In an on-going series of separate studies[1,2], we have examined the effects of varying the mass of Jupiter on the impact flux that the Earth would experience from Near-Earth Objects sourced from the Asteroid belt, short-period comets sourced from the Edgeworth-Kuiper belt, and long-period comets sourced from the Oort cloud. The results are remarkable - it seems that, far from being a shield, Jupiter actually acts to increase the impact flux experienced by the Earth over that which would be expected without the planet. Still more surprising, in the cases of the asteroids and Edgeworth-Kuiper belt objects, it seems that a Jupiter around 0.2 times the mass of "our Jupiter" would be even more threatening, sending a still greater number of objects our way. In order to simulate such disparate populations, different approaches to population construction were needed. The asteroidal and short-period comet populations each contained 100,000 test particles, moving on orbits typical of their class. The asteroids were initially distributed between 2 and 4 AU, with orbits of varying eccentricity and inclination, with number density varying as a function of semi-major axis. The short-period cometary flux was obtained through simulation of a population based on the subset of known Centaurs and Scattered Disk Objects which are Neptune-crossing, and have perihelia beyond the orbit of Uranus. These objects are the parents of the short-period comets, and were chosen since they are a population beyond the current influence of the planet Jupiter. Since our goal was to study the effect of Jupiter's mass on the impact flux at the Earth from the two populations, we followed our 100,000 particle populations for 10 million years, under the influence of the giant planets. Each particle was followed until it either hit something, or was ejected from the system. In this manner, we were able to follow the flux of objects onto the Earth as a function of time. The simulations were repeated over a wide range of Jupiter masses, with all other variables being held constant, allowing us to observe the variations in impact flux as a function of Jovian mass. In the cases of the asteroids and the short-period comets, Jupiter was observed to significantly modify the impact flux which would be experienced by the planet Earth. It was immediately obvious, however, that the old idea that Jupiter shields us from impacts no longer holds. For both of these populations, the lowest impact rates were experienced when the Jupiter-like planet in the system had the lowest mass, rose rapidly to a peak flux at around 0.2 Jupiter masses, before falling away more slowly. Therefore, for the asteroids and short-period comets, it seems that our Jupiter does offer some shielding, when compared to the case where the planet has a mass of around 0.2 MJ, but, compared to the scenario where no Jupiter is present at all (or the Jupiter in question has very low mass), Jupiter actually acts to increase the Earth-bound flux. Simulations are currently underway with the goal of analysing the effects of Jupiter's mass on the impact flux from the long-period comets (deflected inward towards the Earth from the Oort cloud). Further into the future, we intend to study the effects of Jovian position of the impact flux, with the goal of answering, once and for all, the question - "Jupiter - Friend or Foe?".

Establishing a Network of Citizen Scientists to Measure Trans-Neptunian Objects (Invited)

NASA Astrophysics Data System (ADS)

Keller, J. M.; Buie, M. W.

2013-12-01

The Research and Education Cooperative Occultation Network (RECON) is an innovative citizen science project to determine the sizes of trans-Neptunian objects (TNOs) and in particular cold classical Kuiper Belt Objects (KBOs). The project currently involves a pilot network of fourteen communities located north and south of Reno, Nevada (from Tulelake, CA to Tonopah, NV) that have been provided with telescope and camera equipment to record occultation data when TNOs and main belt asteroids pass in front of background stars. Current uncertainties in TNO positions and stellar astrometry limit accurate occultation predictions for TNOs. To address this challenge, RECON will establish a 'picket-fence' of observers every 50 km spread over a 2,000-km baseline. When fully scaled, RECON will involve over forty communities stretching across the Western United States from its border with Canada to Mexico. See map for current telescope sites (green and yellow), planned telescope sites (blue), and shadow path for a 100 km object. The pilot RECON network has been established as a proof-of-concept study for this project. Teachers, amateur astronomers, and community members from California and Nevada were recruited via emails, phone, and face-to-face visits during two trips in Fall 2012. Telescope and camera equipment was tested and delivered to each community in Winter 2013. In April, representatives from each community brought this equipment to a four-day intensive training workshop in Carson City. Since the workshop, RECON has conducted five coordinated occultation campaigns involving Pluto and several main belt asteroids to demonstrate the effectiveness and integrity of the network. In addition to presenting results from these observation campaigns, we will describe lessons learned about recruitment, preparation, and retention of citizen scientists from rural communities to conduct authentic astronomy research. We will also discuss plans for scaling up the full RECON network. Finally, we will frame the RECON project in the broader context of citizen science efforts. This material is based upon work supported by the National Science Foundation under Grant No. AST-1212159. Any opinions, findings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the National Science Foundation (NSF).

VizieR Online Data Catalog: R absolute magnitudes of Kuiper Belt objects (Peixinho+, 2012)

NASA Astrophysics Data System (ADS)

Peixinho, N.; Delsanti, A.; Guilbert-Lepoutre, A.; Gafeira, R.; Lacerda, P.

2012-06-01

Compilation of absolute magnitude HRα, B-R color spectral features used in this work. For each object, we computed the average color index from the different papers presenting data obtained simultaneously in B and R bands (e.g. contiguous observations within a same night). When individual R apparent magnitude and date were available, we computed the HRα=R-5log(r Delta), where R is the R-band magnitude, r and Delta are the helio- and geocentric distances at the time of observation in AU, respectively. When V and V-R colors were available, we derived an R and then HRα value. We did not correct for the phase-angle α effect. This table includes also spectral information on the presence of water ice, methanol, methane, or confirmed featureless spectra, as available in the literature. We highlight only the cases with clear bands in the spectrum, which were reported/confirmed by some other work. The 1st column indicates the object identification number and name or provisional designation; the 2nd column indicates the dynamical class; the 3rd column indicates the average HRα value and 1-σ error bars; the 4th column indicates the average $B-R$ color and 1-σ error bars; the 5th column indicates the most important spectral features detected; and the 6th column points to the bibliographic references used for each object. (3 data files).

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

Dr. Alan Stern, New Horizons principal investigator, speaks on a panel at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. Scientists discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

Dr. Jim Green, Dr. Ed Stone, and Dr. Alan Stern speak on a panel at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. They discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

Dr. Ed Stone, Voyager project scientist, speaks on a panel at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. Scientists discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

Dr. Jim Green, Director of NASA’s Planetary Division, speaks on a panel at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. Scientists discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

The impactor flux in the Pluto-Charon system

NASA Technical Reports Server (NTRS)

Weissman, Paul R.; Stern, S. Alan

1994-01-01

Current impact rates of comets on Pluto and Charon are estimated. It is shown that the dominant sources of impactors are comets from the Kuiper belt and the inner Oort cloud, each of whose perihelion distribution extends across Pluto's orbit. In contrast, long-period comets from the outer Oort cloud are a negligible source of impactors. The total predicted number of craters is not sufficient to saturate the surface areas of either Pluto of Charon over the age of the Solar System. However, heavy cratering may have occurred early in the Solar System's history during clearing of planetesimals from the outer planets' zone.

DUst around NEarby Stars. The survey observational results

NASA Astrophysics Data System (ADS)

Eiroa, C.; Marshall, J. P.; Mora, A.; Montesinos, B.; Absil, O.; Augereau, J. Ch.; Bayo, A.; Bryden, G.; Danchi, W.; del Burgo, C.; Ertel, S.; Fridlund, M.; Heras, A. M.; Krivov, A. V.; Launhardt, R.; Liseau, R.; Löhne, T.; Maldonado, J.; Pilbratt, G. L.; Roberge, A.; Rodmann, J.; Sanz-Forcada, J.; Solano, E.; Stapelfeldt, K.; Thébault, P.; Wolf, S.; Ardila, D.; Arévalo, M.; Beichmann, C.; Faramaz, V.; González-García, B. M.; Gutiérrez, R.; Lebreton, J.; Martínez-Arnáiz, R.; Meeus, G.; Montes, D.; Olofsson, G.; Su, K. Y. L.; White, G. J.; Barrado, D.; Fukagawa, M.; Grün, E.; Kamp, I.; Lorente, R.; Morbidelli, A.; Müller, S.; Mutschke, H.; Nakagawa, T.; Ribas, I.; Walker, H.

2013-07-01

Context. Debris discs are a consequence of the planet formation process and constitute the fingerprints of planetesimal systems. Their solar system counterparts are the asteroid and Edgeworth-Kuiper belts. Aims: The DUNES survey aims at detecting extra-solar analogues to the Edgeworth-Kuiper belt around solar-type stars, putting in this way the solar system into context. The survey allows us to address some questions related to the prevalence and properties of planetesimal systems. Methods: We used Herschel/PACS to observe a sample of nearby FGK stars. Data at 100 and 160 μm were obtained, complemented in some cases with observations at 70 μm, and at 250, 350 and 500 μm using SPIRE. The observing strategy was to integrate as deep as possible at 100 μm to detect the stellar photosphere. Results: Debris discs have been detected at a fractional luminosity level down to several times that of the Edgeworth-Kuiper belt. The incidence rate of discs around the DUNES stars is increased from a rate of ~12.1% ± 5% before Herschel to ~20.2% ± 2%. A significant fraction (~52%) of the discs are resolved, which represents an enormous step ahead from the previously known resolved discs. Some stars are associated with faint far-IR excesses attributed to a new class of cold discs. Although it cannot be excluded that these excesses are produced by coincidental alignment of background galaxies, statistical arguments suggest that at least some of them are true debris discs. Some discs display peculiar SEDs with spectral indexes in the 70-160 μm range steeper than the Rayleigh-Jeans one. An analysis of the debris disc parameters suggests that a decrease might exist of the mean black body radius from the F-type to the K-type stars. In addition, a weak trend is suggested for a correlation of disc sizes and an anticorrelation of disc temperatures with the stellar age. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA.Appendices are available in electronic form at http://www.aanda.orgTables 14 and 15 are also available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A11Full Tables 2-5, 10 and 12 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/555/A11

Towards an understanding of the origin of the Solar system

NASA Astrophysics Data System (ADS)

Griv, Evgeny

Kant (1755) and Laplace (1796) built own hypothesis on the idea of Sun and planets forming from a scattering substance in space. It is well-known the main difficult of the Kant-Laplace hypothesis consists in appearance of angular momentum exploring. Attempts to find a plausible naturalistic explanation of the origin of the solar system in the framework of Safronov's (1969) hypothesis of accretion began about 50 years ago but have not yet been quantitatively successful. Accordingly, planets formed by accretion of solid particles, with or without the presence of gas during the later stages of planetary formation. The main problem is the timescale, which is comparable to or longer than estimates of the lifetime of planet-forming disks. In this work the position is adopted that involve a simultaneous formation of the Sun and the rest of the solar system through a gravitational instability in early solar nebula. In our model, planetary formation is thought to start with inelastically colliding gaseous and dust particles settling to the central plane of this rotating nebula to form a thin layer around the plane. On attaining a certain critical thickness small in comparison with the outer radius of the system, as a result of a local gravitational collapse the nebula disintegrated into the central body ("protosun") and a number of separate protoplanets. The massive gas and dust solar nebula of solar composition is considered, and the gasdynamic theory is used to study the gravitational instability in its protoplanetary disk. The implications for the origin of the solar system are discussed. It is suggested that the large part of the initial mass of protoplanets of the Earth's group was blown away due to intensive thermal emission of the early Sun. Such a point of view is not unnatural since the planets of the Earth's type consist mainly of elements with a high melting temperature and are almost lacking light elements. By adding to the present masses of the terrestrial planets the amount of light gases which is necessary to restore the chemical composition of giant planets, one obtains masses larger by a factor of several hundreds, coincident with the masses of giant planets. We show that a collective process, forming the basis of the disk instability hypothesis, solves with surprising simplicity the two main problems of the dynamical characteristics of the system, which are associated with its observed spacing and orbital momentum distribution, namely, Bode's law on planet spacing and the concentration of angular momentum in the planets and mass in the Sun. Besides, the analysis is found to imply the existence of new planets or other Kuiper-type belts of asteroids at mean distances from the Sun of r11 ≈ 87 AU, r12 ≈ 151 AU, r13 ≈ 261 AU, r14 ≈ 452 AU, r15 ≈ 781 AU (Mercury, . . . , asteroid belt, . . . , Neptune, Kuiper belt, new planets or other Kuiper-type belts). Finally, it is suggested that solar systems analogs may be common throughout the Galaxy.

Does warm debris dust stem from asteroid belts?

NASA Astrophysics Data System (ADS)

Geiler, Fabian; Krivov, Alexander V.

2017-06-01

Many debris discs reveal a two-component structure, with a cold outer and a warm inner component. While the former are likely massive analogues of the Kuiper belt, the origin of the latter is still a matter of debate. In this work, we investigate whether the warm dust may be a signature of asteroid belt analogues. In the scenario tested here, the current two-belt architecture stems from an originally extended protoplanetary disc, in which planets have opened a gap separating it into the outer and inner discs which, after the gas dispersal, experience a steady-state collisional decay. This idea is explored with an analytic collisional evolution model for a sample of 225 debris discs from a Spitzer/IRS catalogue that are likely to possess a two-component structure. We find that the vast majority of systems (220 out of 225, or 98 per cent) are compatible with this scenario. For their progenitors, original protoplanetary discs, we find an average surface density slope of -0.93 ± 0.06 and an average initial mass of (3.3^{+0.4}_{-0.3})× 10^{-3} solar masses, both of which are in agreement with the values inferred from submillimetre surveys. However, dust production by short-period comets and - more rarely - inward transport from the outer belts may be viable, and not mutually excluding, alternatives to the asteroid belt scenario. The remaining five discs (2 per cent of the sample: HIP 11486, HIP 23497, HIP 57971, HIP 85790, HIP 89770) harbour inner components that appear inconsistent with dust production in an 'asteroid belt.' Warm dust in these systems must either be replenished from cometary sources or represent an aftermath of a recent rare event, such as a major collision or planetary system instability.

The Hitchhiker's Guide to the Outer Solar System

NASA Technical Reports Server (NTRS)

Ono, Masahiro; Quadrelli, Marco; Lantoine, Gregory; Backes, Paul; Lopez Ortega, Alejandro; Grip, Havard; Yen, Chen-Wan; Jewitt, David

2015-01-01

We propose a novel deep space propulsion method called the Comet Hitchhiker. The concept is to perform momentum exchange with small bodies (i.e., asteroid and comet) using an extendable/retrievable tether and a harpoon. Unlike previously proposed tethered fly-by, the use of extendable tether enables to change the relative speed with a target. Hence Hitchhiker would be a prospective means of providing orbit insertion deltaV, particularly for rendezvous missions to small bodies in the outer Solar System such as Kuiper belt objects and Centaurs, which are not easily manageable with chemical propulsion or solar electric propulsion. Furthermore, by applying regenerative brake during a hitchhike maneuver, a Hitchhiker can harvest energy. The stored energy can be used to make a departure from the target by quickly retrieving the tether, which we call a inverse hitchhike maneuver. By repeating hitchhike and inverse Hitchhike maneuvers, a Hitchhiker could perform a mission to rendezvous with multiple targets efficiently, which we call a multi-hitchhike mission. We derive the basic equation of Hitchhiker, namely the Space Hitchhike Equation, which relates the specific strength and mass fraction of tether to achievable ?V. We then perform detailed feasibility analysis through finite element simulations of tether as well as hypervelocity impact simulations of the harpoon using the Adaptive Mesh Refinement Objected-oriented C++ (AMROC) algorithm. The analysis results suggest that a hitchhike maneuver with deltaV = approximately 1.5km/s is feasible with flight proven materials such as Kevlar/Zylon tether and tungsten harpoon. A carbon nanotube tether, combined with diamond harpoon, would enable approximately 10 km/s hitchhike maneuver. Finally, we present two particular mission scenarios for Hitchhiker: Pluto rendezvous and a multi-hitchhike mission to the Themis family asteroids in the main belt.

First Asteroid Spectrometric Observations with BTA: 3045 Alois

NASA Astrophysics Data System (ADS)

Busarev, V. V.; Burenkov, A. N.; Pramskij, A. G.

2001-11-01

BTA, Russian 6-m telescope, was mainly used for faint stars and extragalactic objects observations. We have firstly performed with the telescope spectrometric observations of a main belt asteroid, 3045 Alois, and are planning to use it for Centaurs and Kuiper Belt objects spectrometry. We have obtained some results of the observations. Spectra of Alois were recorded on two nights of March 2001 (29/30 and 30/31) with a long slit spectrograph (UAGS + CCD) in the .38-.80 um spectral range. HD105633 (G5) [1] considered as a solar analog was also observed, and the data were used for calculation the asteroid reflectance spectra. It was found that reflectance spectra of Alois obtained on different nights have various continuum slopes and absorption features. The reflectance spectrum on 29/30 March had a flat continuum in the range .44-.65 um and absorption bands at .5 um (ab. 7 % with respect to the continuum) similar to that found on the E-type asteroid 2035 Stearns [2], and at .80 um (ab. 25 %). Another one on 30/31 March had a red continuum in the range .40-.67 um and absorption bands at .43 um (ab. 6 %) resembling absorption features found on some C-, M- and S-type asteroids [3, 4], and at .80 um (ab. 17 %). From the data and taking into account the mean heliocentric distance of 3045 Alois (3.13 AU) we suppose that the asteroid having irregular spectral characteristics may be of M- or E-type and possibly hydrated. Unfortunately, its albedo and rotational period remain still unknown. [1] Mermilliod J.-C. (1994) Bull. Inf. CDS 45, 3. [2] Fornasier S. and Lazzarine M. (2001) Icarus 152, 127-133. [3] Vilas F. et al. (1993) Icarus 102, 225-231. [4] Busarev V. V. (2001) LPSC XXXII, abs. 1927.

Neptune's 5:2 mean motion resonance in the Kuiper Belt

NASA Astrophysics Data System (ADS)

Lan, Lei; Malhotra, Renu

2018-04-01

Recent observations of distant Kuiper belt objects (KBOs) in Neptune's 5:2 mean motion resonance (MMR) present two dynamical puzzles: this third order MMR, located at a semi-major axis of about 55 AU, hosts a surprisingly large population, comparable to the well-known and prominent populations of Plutinos and Twotinos in the 3:2 and the 2:1 MMRs, respectively; secondly, the eccentricities of these resonant KBOs are concentrated near ∼0.4. To shed light on these puzzles, we investigate the phase space structure near this resonance with use of Poincaré sections of the circular planar restricted three body model, for the full range of eccentricities, (0—1). With this non-perturbative numerical analysis, we find that the resonance width in semi-major axis is narrow for very small eccentricities, but widens dramatically for eccentricities ≥ 0.2. The resonance width reaches a maximum near eccentricity 0.4, where it is similar to the maximum widths of the 2:1 and 3:2 MMRs. We confirm these results with numerical simulations of the three dimensional N-body problem of KBOs in the gravitational field of the Sun and the four giant planets; our simulations include a wide range of orbital inclinations of the KBOs relative to the solar system’s invariable plane. From these simulations, we find that the boundaries of the stable zone of the 5:2 MMR in the semimajor axis—eccentricity plane are very similar to those found with the simplified circular planar restricted three body model of the Sun-Neptune-KBO, with the caveat that orbits of eccentricity above ~0.55 are long term unstable; such orbits, which have perihelion distance less than ~25 AU, are phase-protected from close encounters with Neptune but not from destabilizing encounters with Uranus. Additionally, the numerical simulations show that the long term stability of KBOs in Neptune’s 5:2 MMR is only mildly sensitive to KBO inclination. We conclude that the two dynamical puzzles presented by the observations of the KBOs in Neptune’s 5:2 MMR can be understood fairly naturally in light of the phase space structure of this resonance combined with basic considerations of their long term stability.

Collisional Time Scales in the Kuiper Disk and Their Implications

NASA Technical Reports Server (NTRS)

Stern, S. Alan

1995-01-01

We explore the rate of collisions among bodies in the present-day Kuiper Disk as a function of the total mass and population size structure of the disk. We find that collisional evolution is an important evolutionary process in the disk as a whole, and indeed, that it is likely the dominant evolutionary process beyond approx. 42 AU, where dynamical instability time scales exceed the age of the solar system. Two key findings we report from this modeling work are: that unless the disk's population structure is sharply truncated for radii smaller than approx. 1-2 km, collisions between comets and smaller debris are occurring so frequently in the disk, and with high enough velocities, that the small body (i.e., KM-class object) population in the disk has probably developed into a collisional cascade, thereby implying that the Kuiper Disk comets may not all be primordial, and that the rate of collisions of smaller bodies with larger 100 less R less 400 km objects (like 1992QB(sub 1) and its cohorts) is so low that there appears to be a dilemma in explaining how QB(sub 1)s could have grown by binary accretion in the disk as we know it. Given these findings, it appears that either the present-day paradigm for the formation of Kuiper Disk is failed in some fundamental respect, or that the present-day disk is no longer representative of the ancient structure from which it evolved. This in turn suggests the intriguing possibility that the present-day Kuiper Disk evolved through a more erosional stage reminiscent of the disks around the stars Beta Pictorus, alpha PsA, and alpha Lyr.

HST Observations of a Large-Amplitude, Long-Period Trojan: (11351) Leucus

NASA Astrophysics Data System (ADS)

Noll, Keith S.; Levison, Harold F.; Buie, Marc W.; Grundy, William M.

2016-10-01

(11351) Leucus (1997 TS25) is a Trojan that is notable for having one of the longest known rotation periods of any small body, T=514 h. A possible cause for this long period would be the existence of a tidally locked binary similar to the already-known long period binary Trojan, (617) Patroclus. If this were the case, the system would become tidally circularized in a time short compared to the age of the solar system. In such a case, the components would be separated by ~0.18 arcsec at lightcurve maximum, resolvable by WFC3. We carried out observations in June 2016, coordinated with groundbased observations to schedule near a maximum to test whether (11351) Leucus is binary. We describe the results of these observations.Observations of (11351) Leucus are of particular interest because it is a target of the Lucy mission, a Discovery mission currently in phase A and one of five that may be selected in early 2017. Searches for binary Trojans also offer multiple scientific benefits independent of mission status. Orbit-derived mass and density can be used to constrain planetary migration models. Low density is characteristic of bodies found in the dynamically cold Kuiper Belt, a remnant of the solar system's protoplanetary disk. Only one undisputed density has been measured in the Trojans, that of the binary (617) Patroclus, which has a low density of 0.8 g/cm3, similar to the low densities found in the Kuiper Belt. Slow rotators offer a set of targets that are tidally evolved systems and therefore are among the most attractive potential targets for an HST search.

New Horizons Upper Limits on O{sub 2} in Pluto’s Present Day Atmosphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kammer, J. A.; Gladstone, G. R.; Stern, S. A.

The surprising discovery by the Rosetta spacecraft of molecular oxygen (O{sub 2}) in the coma of comet 67P/Churyumov–Gerasimenko challenged our understanding of the inventory of this volatile species on and inside bodies from the Kuiper Belt. That discovery motivated our search for oxygen in the atmosphere of Kuiper Belt planet Pluto, because O{sub 2} is volatile even at Pluto’s surface temperatures. During the New Horizons flyby of Pluto in 2015 July, the spacecraft probed the composition of Pluto’s atmosphere using a variety of observations, including an ultraviolet solar occultation observed by the Alice UV spectrograph. As described in these reports, absorptionmore » by molecular species in Pluto’s atmosphere yielded detections of N{sub 2}, as well as hydrocarbon species such as CH{sub 4}, C{sub 2}H{sub 2}, C{sub 2}H{sub 4}, and C{sub 2}H{sub 6}. Our work here further examines this data to search for UV absorption from molecular oxygen (O{sub 2}), which has a significant cross-section in the Alice spectrograph bandpass. We find no evidence for O{sub 2} absorption and place an upper limit on the total amount of O{sub 2} in Pluto’s atmosphere as a function of tangent height up to 700 km. In most of the atmosphere, this upper limit in line-of-sight abundance units is ∼3 × 10{sup 15} cm{sup −2}, which, depending on tangent height, corresponds to a mixing ratio of 10{sup −6} to 10{sup −4}, far lower than in comet 67P/CG.« less

Spitzer Evidence for a Late Heavy Bombardment and the Formation of Urelites in {eta}Corvi at Approximately 1 Gyr

NASA Technical Reports Server (NTRS)

Lisse, C. M.; Wyatt, M. C.; Chen, C. H.; Morlok, A.; Watson, D. M.; Manj, P.; Sheehan, P.; Currie, T. M.; Thebault, P.; Sitko, M. L.

2011-01-01

We have analyzed Spitzer and NASA/IRTF 2 - 35 micrometer spectra of the warm, 350 K circumstellar dust around the nearby MS star eta Corvi (F2V, 1.4 plus or minus 0.3 Gyr). The spectra show clear evidence for warm, water- and carbon-rich dust at 3 AU from the central star, in the system's Terrestrial Habitability Zone. Spectral features due to ultra-primitive cometary material were found, in addition to features due to impact produced silica and high temperature carbonaceous phases. At least 9 x 10(exp 18) kg of 0.1 - 100 micrometer warm dust is present in a collisional equilibrium distribution with dn/da a(exp -3.5), the equivalent of a 130 km radius KBO of 1.0 grams per cubic centimeter density and similar to recent estimates of the mass delivered to the Earth at 0.6 - 0.8 Gyr during the Late Heavy Bombardment. We conclude that the parent body was a Kuiper-Belt body or bodies which captured a large amount of early primitive material in the first Myrs of the system's lifetime and preserved it in deep freeze at approximately 150 AU. At approximately 1.4 Gyr they were prompted by dynamical stirring of their parent Kuiper Belt into spiraling into the inner system, eventually colliding at 5-10 kilometers per second with a rocky planetary body of mass less than or equal to M(sub Earth at approximately 3 AU, delivering large amounts of water (greater than 0.1 % of M(sub Earth's Oceans)) and carbon-rich material. The Spitzer spectrum also closely matches spectra reported for the Ureilite meteorites of the Sudan Almahata Sitta fall in 2008, suggesting that one of the Ureilite parent bodies was a KBO.

Kuipers conducts ARGES experiment OPS at the MSG during EXP 8 / EXP 9

NASA Image and Video Library

2004-04-24

ISS008-E-22128 (24 April 2004) --- European Space Agency (ESA) astronaut Andre Kuipers of the Netherlands works with the ARGES experiment for the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station (ISS). The main objectives of ARGES are to determine which factors are critical in the onset of instabilities in High-Intensity Discharge (HID) lamps and to characterize the separation of individual gaseous elements inside.

Comparison of the Mineralogy of Comet Wild 2 Coma Grains to Other Astromaterials

NASA Technical Reports Server (NTRS)

Frank, David; Zolensky, Michael

2010-01-01

We propose that Kuiper Belt samples (in this case comet coma grains from the Jupiter family comet Wild 2) are recognizably different from the bulk of materials in outer belt asteroids, because of their different formation positions and times in the early solar system. We believe this despite similarities found between some Wild 2 grains and components of carbonaceous chondrites (i.e. some CAI and chondrules). Kuiper Belt samples must preserve measurable mineralogical and compositional evidence of formation at unique positions and times in the early solar nebula, and these formational differences must have imparted recognizable special characteristics. We hypothesize that these characteristics include: (1) Unique major element compositional ranges of common astromaterial minerals, especially olivine and pyroxene; (2) Unique minor element compositions of major silicate phases, especially olivine and low-Ca pyroxene; (3) Degree and effects of radiation processing -- including amorphous rims, metal coatings, and Glass with Embedded Metal and Sulfides (GEMS); (4) Presence of abundant presolar silicate grains as recognized by anomalous oxygen in silicates; (5) Oxidation state of the mineral assemblage. We are working our way through all available Wild 2 samples, selecting 1-2 non-consecutive viable TEM grids from each possible extracted Wild 2 grain. We especially prefer TEM grids from grains for which complete mineralogical details have not been published (which is to say the majority of the extracted grains). We are performing a basic mineralogic survey by E-beam techniques, to establish the essential features of the extracted Wild 2 grains. We are making a particular effort to carefully and accurately measure minor elements of olivine and pyroxene, as these minerals are widespread in astromaterials, and comparisons of their compositions will serve to place the Wild 2 silicates in contact with asteroids, meteorites and chondritic interplanetary dust particles processing. We are also making a special effort to search for mineralogical products of aqueous alteration, since their presence would reveal that Wild 2 was once internally heated, a result with dramatic implications for models of early solar system primitive bodies. Thus far carbonates are the only potential evidence for aqueous alteration for Wild 2.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Muñoz-Gutiérrez, M. A.; Pichardo, B.; Peimbert, A.

With the use of long-term numerical simulations, we study the evolution and orbital behavior of cometary nuclei in cold Kuiper belt–like debris disks under the gravitational influence of dwarf planets (DPs); we carry out these simulations with and without the presence of a Neptune-like giant planet. This exploratory study shows that in the absence of a giant planet, 10 DPs are enough to induce strong radial and vertical heating on the orbits of belt particles. On the other hand, the presence of a giant planet close to the debris disk, acts as a stability agent reducing the radial and verticalmore » heating. With enough DPs, even in the presence of a Neptune-like giant planet some radial heating remains; this heating grows steadily, re-filling resonances otherwise empty of cometary nuclei. Specifically for the solar system, this secular process seems to be able to provide material that, through resonant chaotic diffusion, increase the rate of new comets spiraling into the inner planetary system, but only if more than the ∼10 known DP sized objects exist in the trans-Neptunian region.« less

THE TAIWAN-AMERICAN OCCULTATION SURVEY PROJECT STELLAR VARIABILITY. I. DETECTION OF LOW-AMPLITUDE {delta} SCUTI STARS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kim, D.-W.; Protopapas, P.; Alcock, C.

2010-02-15

We analyzed data accumulated during 2005 and 2006 by the Taiwan-American Occultation Survey (TAOS) in order to detect short-period variable stars (periods of {approx}<1 hr) such as {delta} Scuti. TAOS is designed for the detection of stellar occultation by small-size Kuiper Belt Objects and is operating four 50 cm telescopes at an effective cadence of 5 Hz. The four telescopes simultaneously monitor the same patch of the sky in order to reduce false positives. To detect short-period variables, we used the fast Fourier transform algorithm (FFT) in as much as the data points in TAOS light curves are evenly spaced.more » Using FFT, we found 41 short-period variables with amplitudes smaller than a few hundredths of a magnitude and periods of about an hour, which suggest that they are low-amplitude {delta} Scuti stars. The light curves of TAOS {delta} Scuti stars are accessible online at the Time Series Center Web site (http://timemachine.iic.harvard.edu)« less

Science Opportunities with the Near-IR Camera (NIRCam) on the James Webb Space Telescope (JWST)

NASA Technical Reports Server (NTRS)

Beichman, Charles A.; Rieke, Marcia; Eisenstein, Daniel; Greene, Thomas P.; Krist, John; McCarthy, Don; Meyer, Michael; Stansberry, John

2012-01-01

The Near-Infrared Camera (NIRCam) on the James Webb Space Telescope (JWST) offers revolutionary gains in sensitivity throughout the 1-5 micrometer region. NIRCam will enable great advances in all areas of astrophysics, from the composition of objects in our own Kuiper Belt and the physical properties of planets orbiting nearby stars to the formation of stars and the detection of the youngest galaxies in the Universe. NIRCam also plays an important role in initial alignment of JWST and the long term maintenance of its image quality. NIRCam is presently undergoing instrument Integration and Test in preparation for delivery to the JWST project. Key near-term milestones include the completion of cryogenic testing of the entire instrument; demonstration of scientific and wavefront sensing performance requirements; testing of replacement H2RG detectors arrays; and an analysis of coronagraphic performance in light of measured telescope wavefront characteristics. This paper summarizes the performance of NIRCam, the scientific and education/outreach goals of the science team, and some results of the on-going testing program.

Density of transneptunian object 229762 2007 UK126

NASA Astrophysics Data System (ADS)

Grundy, Will

2017-08-01

Densities provide unique information about bulk composition and interior structure and are key to going beyond the skin-deep view offered by remote-sensing techniques based on photometry, spectroscopy, and polarimetry. They are known for a handful of the relict planetesimals that populate our Solar System's Kuiper belt, revealing intriguing differences between small and large bodies. More and better quality data are needed to address fundamental questions about how planetesimals form from nebular solids, and how distinct materials are distributed through the nebula. Masses from binary orbits are generally quite precise, but a problem afflicting many of the known densities is that they depend on size estimates from thermal emission observations, with large model-dependent uncertainties that dominate the error bars on density estimates. Stellar occultations can provide much more accurate sizes and thus densities, but they depend on fortuitous geometry and thus can only be done for a few particularly valuable binaries. We propose observations of a system where an accurate density can be determined: 229762 2007 UK126. An accurate size is already available from multiple stellar occultation chords. This proposal will determine the mass, and thus the density.

KSC-05pd2416

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility, the media (also dressed in clean room suits) learn about NASA’s New Horizons spacecraft (at left) from New Horizons Mission Systems Engineer David Kusnierkiewicz, in the center. Behind Kusnierkiewicz is one half of the fairing that will enclose the spacecraft for launch, scheduled for January 2006. The media event brought photographers and reporters to the site to talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2412

NASA Image and Video Library

2005-11-04

KENNEDY SPACE CENTER, FLA. - In the clean room at KSC’s Payload Hazardous Servicing Facility is NASA’s New Horizons spacecraft that is scheduled to be launched to Pluto and its moon Charon in January 2006. Seen here is the Radio Science Experiment (REX) that will measure atmospheric composition and temperature. The spacecraft is being prepared for a media event. Photographers and reporters will be able to photograph the New Horizons spacecraft and talk with project management and test team members from NASA and the Johns Hopkins University Applied Physics Laboratory. Carrying seven scientific instruments, the compact 1,060-pound New Horizons probe will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will fly by Pluto and Charon as early as summer 2015.

KSC-05pd2616

NASA Image and Video Library

2005-12-15

KENNEDY SPACE CENTER, FLA. - In the communications room above the Atlas V Spaceflight Operations Center on Cape Canaveral Air Force Station, NASA Public Information Officer George Diller rehearses his role for the upcoming launch of the New Horizons spacecraft. Behind him are Tiffany Nail, with the Launch Services Program at Kennedy Space Center, and Bob Summerville, a Lockheed Martin console system software engineer. Members of the New Horizons team are taking part in a dress rehearsal for the launch scheduled in mid-January. New Horizons carries seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015.

First Solar System Results of the Spitzer Space Telescope

NASA Technical Reports Server (NTRS)

VanCleve, J.; Cruikshank, D. P.; Stansberry, J. A.; Burgdorf, M. J.; Devost, D.; Emery, J. P.; Fazio, G.; Fernandez, Y. R.; Glaccum, W.; Grillmair, C.

2004-01-01

The Spitzer Space Telescope, formerly known as SIRTF, is now operational and delivers unprecedented sensitivity for the observation of Solar System targets. Spitzer's capabilities and first general results were presented at the January 2004 AAS meeting. In this poster, we focus on Spitzer's performance for moving targets, and the first Solar System results. Spitzer has three instruments, IRAC, IRS, and MIPS. IRAC (InfraRed Array Camera) provides simultaneous images at wavelengths of 3.6, 4.5, 5.8, and 8.0 microns. IRS (InfraRed Spectrograph) has 4 modules providing low-resolution (R=60-120) spectra from 5.3 to 40 microns, high-resolution (R=600) spectra from 10 to 37 m, and an autonomous target acquisition system (PeakUp) which includes small-field imaging at 15 m. MIPS (Multiband Imaging Photometer for SIRTF) does imaging photometry at 24, 70, and 160 m and low-resolution (R=15-25) spectroscopy (SED) between 55 and 96 microns. Guaranteed Time Observer (GTO) programs include the moons of the outer Solar System, Pluto, Centaurs, Kuiper Belt Objects, and comets

Serpentinization and the Formation of H2 and CH4 on Celestial Bodies (Planets, Moons, Comets).

PubMed

Holm, N G; Oze, C; Mousis, O; Waite, J H; Guilbert-Lepoutre, A

2015-07-01

Serpentinization involves the hydrolysis and transformation of primary ferromagnesian minerals such as olivine ((Mg,Fe)2SiO4) and pyroxenes ((Mg,Fe)SiO3) to produce H2-rich fluids and a variety of secondary minerals over a wide range of environmental conditions. The continual and elevated production of H2 is capable of reducing carbon, thus initiating an inorganic pathway to produce organic compounds. The production of H2 and H2-dependent CH4 in serpentinization systems has received significant interdisciplinary interest, especially with regard to the abiotic synthesis of organic compounds and the origins and maintenance of life in Earth's lithosphere and elsewhere in the Universe. Here, serpentinization with an emphasis on the formation of H2 and CH4 are reviewed within the context of the mineralogy, temperature/pressure, and fluid/gas chemistry present in planetary environments. Whether deep in Earth's interior or in Kuiper Belt Objects in space, serpentinization is a feasible process to invoke as a means of producing astrobiologically indispensable H2 capable of reducing carbon to organic compounds.

The Lightcurve of New Horizons Encounter TNO 2014 MU69

NASA Astrophysics Data System (ADS)

Benecchi, Susan

2016-10-01

The New Horizons spacecraft was recently redirected to encounter the Transneptunian Object (TNO) 2014 MU69 on 1 January 2019. In order to optimally plan the fly-by sequencing, we must learn as much about this object in advance of the encounter as possible. In particular, it is critical that we determine, to the best of our ability, if the object is binary (as is the case for 20% of cold classical TNOs in this size range), the rotation period and shape of the body. All of these parameters influence the encounter design and timing. Existing and proposed HST astrometric datasets constrain its diameter (21-41 km for an albedo of 0.15-0.04) and orbit, and suggest a rotational lightcurve amplitude of >0.3 mags, but cannot determine the rotation period or lightcurve shape. To that end we propose to use 24 HST orbits over 4 days to measure the lightcurve amplitude of 2014 MU69, and constrain its rotation period to better than 5%. 2014 MU69's orbit identifies it as very typical member of the cold classical TNO population. This makes it an ideal target for our spacecraft mission because close-up observations obtained of 2014 MU69 can be extrapolated to understand the cold classical population as a whole, which is the most primitive and least disturbed part of the Kuiper Belt.

New Horizons Event: The First Mission to the Pluto System

NASA Image and Video Library

2014-08-25

Audience members view slides from a presentation by Dr. Jim Green, Dr. Ed Stone, and Dr. Alan Stern at the "New Horizons: The First Mission to the Pluto System and the Kuiper Belt" Event at NASA Headquarters in Washington, DC Monday, August 25, 2014. They discussed how the first images of Pluto and its moons would be captured by the New Horizons spacecraft during a five month long reconnaissance flyby study starting in the summer of 2015. New Horizons launched on January 19, 2006 and is scheduled to make its closest approach to Pluto on July 14, 2015. Photo Credit: (NASA/Aubrey Gemignani)

Non-Solar Photovoltaics for Small Space Missions

NASA Technical Reports Server (NTRS)

Landis, Geoffrey A.; Bailey, Sheila G.; Clark, Eric B.; Myers, Matthew G.; Piszazor, Michael F.; Murbach, Marcus S.

2012-01-01

NASA has missions planned to targets in the solar system ranging from the permanently shadowed craters of Mercury to the icy reaches of the Kuiper belt and beyond. In 2011, the NASA Office of the Chief Technologist (OCT) requested the NASA Ames and Glenn Research Centers to assess the potential of small power supplies based on direct conversion of energy from radioisotope sources for future NASA missions; and in particular to assess whether alphavoltaic and betavoltaic power sources could be of potential benefit in small missions, as well as examining the use of miniaturized thermophotovoltaic power supplies. This paper summarizes the results of that assessment.

Colors and Shapes of the Irregular Planetary Satellites

NASA Astrophysics Data System (ADS)

Graykowski, Ariel; Jewitt, David

2018-04-01

It is widely recognized that the irregular satellites of the giant planets were captured from initially heliocentric orbits. However, the mechanism of capture and the source region from which they were captured both remain unknown. We present an optical color survey of 43 irregular satellites of the outer planets conducted using the LRIS camera on the 10 m telescope at the Keck Observatory in Hawaii. The measured colors are compared to other planetary bodies in search for similarities and differences that may reflect upon the origin of the satellites. We find that ultrared matter (with color index B–R ≥ 1.6), while abundant in the Kuiper Belt and Centaur populations, is depleted from the irregular satellites. We also use repeated determinations of the absolute magnitudes to make a statistical estimate of the average shape of the irregular satellites. The data provide no evidence that the satellites and the main-belt asteroids are differently shaped, consistent with collisions as the major agent shaping both.

Water-Rock Differentiation of Icy Bodies by Darcy law, Stokes law, and Two-Phase Flow

NASA Astrophysics Data System (ADS)

Neumann, Wladimir; Breuer, Doris; Spohn, Tilman

2016-10-01

The early Solar system produced a variety of bodies with different properties. Among the small bodies, objects that contain notable amounts of water ice are of particular interest. Water-rock separation on such worlds is probable and has been confirmed in some cases. We couple accretion and water-rock separation in a numerical model. The model is applicable to Ceres, icy satellites, and Kuiper belt objects, and is suited to assess the thermal metamorphism of the interior and the present-day internal structures. The relative amount of ice determines the differentiation regime according to porous flow or Stokes flow. Porous flow considers differentiation in a rock matrix with a small degree of ice melting and is typically modelled either with the Darcy law or two-phase flow. We find that for small icy bodies two-phase flow differs from the Darcy law. Velocities derived from two-phase flow are at least one order of magnitude smaller than Darcy velocities. The latter do not account for the matrix resistance against the deformation and overestimate the separation velocity. In the Stokes regime that should be used for large ice fractions, differentiation is at least four orders of magnitude faster than porous flow with the parameters used here.

Formation of doubly and triply bonded unsaturated compounds HCN, HNC, and CH2NH via N + CH4 low-temperature solid state reaction: from molecular clouds to solar system objects

NASA Astrophysics Data System (ADS)

Mencos, Alejandro; Krim, Lahouari

2018-06-01

We show in the current study carried out in solid phase at cryogenic temperatures that methane (CH4) ice exposed to nitrogen atoms is a source of two acids HCN, HNC, and their corresponding hydrogenated unsaturated species CH2NH, in addition to CH3, C2H6, CN-, and three nitrogen hydrides NH, NH2, and NH3. The solid state N + CH4 reaction taken in the ground state seems to be strongly temperature dependent. While at temperatures lower than 10 K only CH3, NH, NH2, and NH3 species formation is promoted due to CH bond dissociation and NH bond formation, stable compounds with CN bonds are formed at temperatures ranged between 10 and 40 K. Many of these reaction products, resulting from CH4 + N reaction, have already been observed in N2-rich regions such as the atmospheres of Titan, Kuiper belt objects, and molecular clouds of the interstellar medium. Our results show the power of the solid state N-atom chemistry in the transformation of simple astrochemical relevant species, such as CH4 molecules and N atoms into complex organic molecules which are also potentially prebiotic species.

Hubble 2006: Science Year in Review

NASA Technical Reports Server (NTRS)

Brown, R.

2007-01-01

The 10 science articles selected for this years annual science report exemplify the range of Hubble research from the Solar System, across our Milky Way, and on to distant galaxies. The objects of study include a new feature on Jupiter, binaries in the Kuiper Belt, Cepheid variable stars, the Orion Nebula, distant transiting planets, lensing galaxies, active galactic nuclei, red-and-dead galaxies, and galactic outflows and jets. Each narrative strives to construct the readers understanding of the topics and issues, and to place the latest research in historical, as well as scientific, context. These essays reveal trends in the practice of astronomy. More powerful computers are permitting astronomers to study ever larger data sets, enabling the discovery of subtle effects and rare objects. (Two investigations created mosaic images that are among the largest produced to date.) Multiwavelength data sets from ground-based telescopes, as well as other great observatories Spitzer and Chandraare increasingly important for holistic interpretations of Hubble results. This yearbook also presents profiles of 12 individuals who work with Hubble, or Hubble data, on a daily basis. They are representative of the many students, scientists, engineers, and other professions who are proudly associated with Hubble. Their stories collectively communicate the excitement and reward of careers related to space science and technology.

A kinetic study of the formation of organic solids from formaldehyde: Implications for the origin of extraterrestrial organic solids in primitive Solar System objects

NASA Astrophysics Data System (ADS)

Kebukawa, Yoko; Cody, George D.

2015-03-01

Aqueous organic solid formation from formaldehyde via the formose reaction and subsequent reactions is a possible candidate for the origin of complex primitive chondritic insoluble organic matter (IOM) and refractory carbon in comets. The rate of formation of organic solids from formaldehyde was studied as a function of temperature and time, with and without ammonia, in order to derive kinetic expressions for polymer yield. The evolution in molecular structure as a function of time and temperature was studied using infrared spectroscopy. Using these kinetic expressions, the yield of organic solids is estimated for extended time and temperature ranges. For example, the half-life for organic solid formation is ∼5 days at 373 K, ∼200 days at 323 K, and ∼70 years at 273 K with ammonia, and ∼25 days at 373 K, ∼13 years at 323 K, and ∼2 × 104 years at 273 K without ammonia. These results indicate that organic solids could form during the aqueous alteration in meteorite parent bodies. If liquid water existed early in the interiors of Kuiper belt objects (KBOs), formaldehyde could convert into organic solids at temperatures close to 273 K, and possibly even below 273 K in the ammonia-water system.

Two objects in Neptune's 9:1 resonance -- implications for resonance sticking in the scattering population

NASA Astrophysics Data System (ADS)

Volk, Kathryn; Murray-Clay, Ruth; Gladman, Brett; Lawler, Samantha; Yu, Tze Yeung Mathew; Alexandersen, Mike; Bannister, Michele; Chen, Ying-Yung; Dawson, Rebekah; Greenstreet, Sarah; Gwyn, Stephen; Kavelaars, J. J.; Lin, Hsing Wen; Lykawka, Patryk; Petit, Jean-Marc

2018-04-01

We discuss the detection in the Outer Solar System Origins Survey (OSSOS) of two objects in Neptune's distant 9:1 mean motion resonance at semimajor axis a≈130 au. Both objects are securely resonant on 10 Myr timescales, with one securely in the 9:1 resonance's leading asymmetric libration island and the other in either the symmetric or trailing asymmetric island. These two objects are the largest semimajor axis objects known with secure resonant classifications, and their detection in a carefully characterized survey allows for the first robust population estimate for a resonance beyond 100 au. The detection of these two objects implies a population in the 9:1 resonance of 1.1×104 objects with Hr<8.66 (D > 100 km) on similar orbits, with 95% confidence range of ∼0.4‑3×104. Integrations over 4 Gyr of an ensemble of clones chosen from within the orbit fit uncertainties for these objects reveal that they both have median resonance occupation timescales of ∼1 Gyr. These timescales are consistent with the hypothesis that these two objects originate in the scattering population but became transiently stuck to Neptune's 9:1 resonance within the last ∼1 Gyr of solar system evolution. Based on simulations of a model of the current scattering population, we estimate the expected resonance sticking population in the 9:1 resonance to be 1000--5000 objects with Hr<8.66 this is marginally consistent with the OSSOS 9:1 population estimate. We conclude that resonance sticking is a plausible explanation for the observed 9:1 population, but we also discuss the possibility of a primordial 9:1 population, which would have interesting implications for the Kuiper belt's dynamical history.

Modeling KBOs Charon, Orcus and Salacia by means of a new equation of state for porous icy bodies

NASA Astrophysics Data System (ADS)

Malamud, U.; Prialnik, D.

2015-10-01

We use a one-dimensional adaptive-grid thermal evolution code to model intermediate sized Kuiper belt objects Charon, Orcus and Salacia and compare their measured bulk densities with those resulting from evolutionary calculations at the end of 4.6 Gyr. Our model assumes an initial homogeneous composition of mixed ice and rock, and follows the multiphase flow of water through the porous rocky medium, consequent differentiation and aqueous chemical alterations in the rock. Heating sources include long-lived radionuclides, serpentinization reactions, release of gravitational potential energy due to compaction, and crystallization of amorphous ice. The density profile is calculated by assuming hydrostatic equilibrium to be maintained through changes in composition, pressure and temperature. To this purpose, we construct an equation of state suitable for porous icy bodies with radii of a few hundred km, based on the best available empirical studies of ice and rock compaction, and on comparisons with rock porosities in Earth analog and Solar System silicates. We show that the observed bulk densities can be reproduced by assuming the same set of initial and physical parameters, including the same rock/ice mass ratio for all three bodies. We conclude that the mass of the object uniquely determines the evolution of porosity, and thus explains the observed differences in bulk density. The final structure of all three objects is differentiated, with an inner rocky core, and outer ice-enriched mantle. The degree of differentiation, too, is determined by the object's mass.

The LCOGT Near Earth Object (NEO) Follow-up Network

NASA Astrophysics Data System (ADS)

Lister, Tim; Gomez, Edward; Christensen, Eric; Larson, Steve

2014-11-01

Las Cumbres Observatory Global Telescope (LCOGT) network is a planned homogeneous network of over 35 telescopes at 6 locations in the northern and southern hemispheres. This network is versatile and designed to respond rapidly to target of opportunity events and also to do long term monitoring of slowly changing astronomical phenomena. The global coverage of the network and the apertures of telescope available make LCOGT ideal for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects (NEOs)) and ultimately for the discovery of new objects.LCOGT has completed the first phase of the deployment with the installation and commissioning of nine 1-meter telescopes at McDonald Observatory (Texas), Cerro Tololo (Chile), SAAO (South Africa) and Siding Spring Observatory (Australia). The telescope network is now operating and observations are being executed remotely and robotically.I am using the LCOGT network to confirm newly detected NEO candidates produced by the major sky surveys such as Catalina Sky Survey (CSS), NEOWISE and PanSTARRS (PS1). Over 600 NEO candidates have been targeted so far this year with 250+ objects reported to the MPC, including 70 confirmed NEOs. An increasing amount of time is being spent to obtain follow-up astrometry and photometry for radar-targeted objects in order to improve the orbits and determine the rotation periods. This will be extended to obtain more light curves of other NEOs which could be Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) or Asteroid Retrieval Mission (ARM) targets. Recent results have included the first period determination for the Apollo 2002 NV16 and our first NEO spectrum from the FLOYDS spectrographs on the LCOGT 2m telescopes obtained for 2012 DA14 during the February 2013 closepass.

Foale and Kuipers conduct ARGES experiment OPS at the MSG during EXP 8 / EXP 9

NASA Image and Video Library

2004-04-24

ISS008-E-22127 (24 April 2004) --- Astronaut C. Michael Foale (left), Expedition 8 commander and NASA ISS science officer, and European Space Agency (ESA) astronaut Andre Kuipers of the Netherlands work with the ARGES experiment for the Microgravity Science Glovebox (MSG) in the Destiny laboratory of the International Space Station (ISS). The main objectives of ARGES are to determine which factors are critical in the onset of instabilities in High-Intensity Discharge (HID) lamps and to characterize the separation of individual gaseous elements inside.

Mid-Infrared Spectroscopy of Mercury from the Kuiper Airborne Observatory

NASA Astrophysics Data System (ADS)

Sprague, A. L.; Witteborn, F. C.; Kozlowski, R. W. H.; Wooden, D. H.

1996-03-01

We present mid-infrared (5 - 10mic) spectroscopic measurements of the planet Mercury obtained from the Kuiper Airborne Observatory (KAO) using the High Efficiency Infrared Faint Object Grating Spectrograph (HIFOGS). Spectra show features characteristic of plagioclase feldspar that was previously observed near 120 deg mercurian longitude. The spectra also show spectral features that could be interpreted indicative of the presence of pyrrhotite (pyrr). An analysis that fully accounts for the effects of large field of view (FOV), thermal gradients, rough surface and absolute calibration is still underway.

Chaos in the Solar System

NASA Technical Reports Server (NTRS)

Lecar, Myron; Franklin, Fred A.; Holman, Matthew J.; Murray, Norman J.

2001-01-01

The physical basis of chaos in the solar system is now better understood: In all cases investigated so far, chaotic orbits result from overlapping resonances. Perhaps the clearest examples are found in the asteroid belt. Overlapping resonances account for its kirkwood gaps and were used to predict and find evidence for very narrow gaps in the outer belt. Further afield, about one new "short-peroid" comet is discovered each year. They are believed to come from the "Kuiper Belt" (at 40 AU or more) via chaotic orbits produced by mean-motion and secular resonances with Neptune. Finally, the planetary system itself is not immune from chaos. In the inner solar system, overlapping secular resonances have been identified as the possible source of chaos. For example, Mercury in 1012 years, may suffer a close encounter with Venus or plunge into the Sun. In the outer solar system, three-body resonances have been identified as a source of chaos, but on an even longer time scale of 109 times the age of the solar system. On the human time scale, the planets do follow their orbits in a stately procession, and we can predict their trajectories for hundreds of thousands of years. That is because the mavericks, with shorter instability times, have long since been ejected. The solar system is not stable; it is just old!

The Zodiacal Emission Spectrum as Determined by COBE and its Implications

NASA Technical Reports Server (NTRS)

Fixsen, D. J.; Dwek, Eli; Oliversen, R. (Technical Monitor)

2002-01-01

We combine observations from the DIRBE and FIRAS instruments on the COBE satellite to derive an annually-averaged spectrum of the zodiacal cloud in the 10 to 1000 micron wavelength region. The spectrum exhibits a break at approx. 150 microns which indicates a sharp break in the dust size distribution at a radius of about 30 microns The spectrum can be fit with a single blackbody with a lambda(exp -2) emissivity law beyond 150 microns and a temperature of 240 K. We also used a more realistic characterization of the cloud to fit the spectrum, including a distribution of dust temperatures, representing different dust compositions and distances from the sun, as well as a realistic representation of the spatial distribution of the dust. We show that amorphous carbon and silicate dust with respective temperatures of 280 and 274 K at 1 AU, and size distributions with a break at grain radii of 14 and 32 microns, can provide a good fit to the average zodiacal dust spectrum. The total mass of the zodiacal cloud is 2 to 11 Eg (Eg=10(exp 18) g), depending on the grain composition. The lifetime of the cloud, against particle loss by Poynting- Robertson drag and the effects of solar wind, is about 10(exp 5) yr. The required replenishment rate is approx. 10(exp 14) g/yr. If this is provided by asteroid belt alone, the asteroids lifetime would be approx. 3 x 10(exp 10) yr. But comets and Kuiper belt objects may also contribute to the zodiacal cloud.

Isotopic compositions of cometary matter returned by Stardust.

PubMed

McKeegan, Kevin D; Aléon, Jerome; Bradley, John; Brownlee, Donald; Busemann, Henner; Butterworth, Anna; Chaussidon, Marc; Fallon, Stewart; Floss, Christine; Gilmour, Jamie; Gounelle, Matthieu; Graham, Giles; Guan, Yunbin; Heck, Philipp R; Hoppe, Peter; Hutcheon, Ian D; Huth, Joachim; Ishii, Hope; Ito, Motoo; Jacobsen, Stein B; Kearsley, Anton; Leshin, Laurie A; Liu, Ming-Chang; Lyon, Ian; Marhas, Kuljeet; Marty, Bernard; Matrajt, Graciela; Meibom, Anders; Messenger, Scott; Mostefaoui, Smail; Mukhopadhyay, Sujoy; Nakamura-Messenger, Keiko; Nittler, Larry; Palma, Russ; Pepin, Robert O; Papanastassiou, Dimitri A; Robert, François; Schlutter, Dennis; Snead, Christopher J; Stadermann, Frank J; Stroud, Rhonda; Tsou, Peter; Westphal, Andrew; Young, Edward D; Ziegler, Karen; Zimmermann, Laurent; Zinner, Ernst

2006-12-15

Hydrogen, carbon, nitrogen, and oxygen isotopic compositions are heterogeneous among comet 81P/Wild 2 particle fragments; however, extreme isotopic anomalies are rare, indicating that the comet is not a pristine aggregate of presolar materials. Nonterrestrial nitrogen and neon isotope ratios suggest that indigenous organic matter and highly volatile materials were successfully collected. Except for a single (17)O-enriched circumstellar stardust grain, silicate and oxide minerals have oxygen isotopic compositions consistent with solar system origin. One refractory grain is (16)O-enriched, like refractory inclusions in meteorites, suggesting that Wild 2 contains material formed at high temperature in the inner solar system and transported to the Kuiper belt before comet accretion.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Morales, F. Y.; Bryden, G.; Werner, M. W.

We present dual-band Herschel /PACS imaging for 59 main-sequence stars with known warm dust ( T {sub warm} ∼ 200 K), characterized by Spitzer . Of 57 debris disks detected at Herschel wavelengths (70 and/or 100 and 160 μ m), about half have spectral energy distributions (SEDs) that suggest two-ring disk architectures mirroring that of the asteroid–Kuiper Belt geometry; the rest are consistent with single belts of warm, asteroidal material. Herschel observations spatially resolve the outer/cold dust component around 14 A-type and 4 solar-type stars with two-belt systems, 15 of which for the first time. Resolved disks are typically observedmore » with radii >100 AU, larger than expected from a simple blackbody fit. Despite the absence of narrow spectral features for ice, we find that the shape of the continuum, combined with resolved outer/cold dust locations, can help constrain the grain size distribution and hint at the dust’s composition for each resolved system. Based on the combined Spitzer /IRS+Multiband Imaging Photometer (5-to-70 μ m) and Herschel /PACS (70-to-160 μ m) data set, and under the assumption of idealized spherical grains, we find that over half of resolved outer/cold belts are best fit with a mixed ice/rock composition. Minimum grain sizes are most often equal to the expected radiative blowout limit, regardless of composition. Three of four resolved systems around the solar-type stars, however, tend to have larger minimum grains compared to expectation from blowout ( f {sub MB} = a {sub min}/ a {sub BOS} ∼ 5). We also probe the disk architecture of 39 Herschel -unresolved systems by modeling their SEDs uniformly, and find them to be consistent with 31 single- and 8 two-belt debris systems.« less

On the state of water ice on saturn's moon Titan and implications to icy bodies in the outer solar system.

PubMed

Zheng, Weijun; Jewitt, David; Kaiser, Ralf I

2009-10-22

The crystalline state of water ice in the Solar System depends on the temperature history of the ice and the influence of energetic particles to which it has been exposed. We measured the infrared absorption spectra of amorphous and crystalline water ice in the 10-50 K and 10-140 K temperature ranges, respectively, and conducted a systematic experimental study to investigate the amorphization of crystalline water ice via ionizing radiation irradiation at doses of up to 160 +/- 30 eV per molecule. We found that crystalline water ice can be converted only partially to amorphous ice by electron irradiation. The experiments showed that a fraction of the 1.65 microm band, which is characteristic for crystalline water ice, survived the irradiation, to a degree that strongly depends on the temperature. Quantitative kinetic fits of the temporal evolution of the 1.65 mum band clearly demonstrate that there is a balance between thermal recrystallization and irradiation-induced amorphization, with thermal recrystallizaton dominant at higher temperatures. Our experiments show the amorphization at 40 K was incomplete, in contradiction to Mastrapa and Brown's conclusion (Icarus 2006, 183, 207.). At 50 K, the recrystallization due to thermal effects is strong, and most of the crystalline ice survived. Temperatures of most icy objects in the Solar System, including Jovian satellites, Saturnian satellites (including Titan), and Kuiper Belt Objects, are equal to or above 50 K; this explains why water ice detected on those objects is mostly crystalline.

A Method to Constrain the Size of the Protosolar Nebula

NASA Astrophysics Data System (ADS)

Kretke, K. A.; Levison, H. F.; Buie, M. W.; Morbidelli, A.

2012-04-01

Observations indicate that the gaseous circumstellar disks around young stars vary significantly in size, ranging from tens to thousands of AU. Models of planet formation depend critically upon the properties of these primordial disks, yet in general it is impossible to connect an existing planetary system with an observed disk. We present a method by which we can constrain the size of our own protosolar nebula using the properties of the small body reservoirs in the solar system. In standard planet formation theory, after Jupiter and Saturn formed they scattered a significant number of remnant planetesimals into highly eccentric orbits. In this paper, we show that if there had been a massive, extended protoplanetary disk at that time, then the disk would have excited Kozai oscillations in some of the scattered objects, driving them into high-inclination (i >~ 50°), low-eccentricity orbits (q >~ 30 AU). The dissipation of the gaseous disk would strand a subset of objects in these high-inclination orbits; orbits that are stable on Gyr timescales. To date, surveys have not detected any Kuiper-belt objects with orbits consistent with this dynamical mechanism. Using these non-detections by the Deep Ecliptic Survey and the Palomar Distant Solar System Survey we are able to rule out an extended gaseous protoplanetary disk (RD >~ 80 AU) in our solar system at the time of Jupiter's formation. Future deep all sky surveys such as the Large Synoptic Survey Telescope will allow us to further constrain the size of the protoplanetary disk.

Great Expectations: The New Horizons Imaging and Composition Pre-Encounter Plans and Contemplations of 2014 MU69

NASA Astrophysics Data System (ADS)

Moore, J. M.; Grundy, W. M.; Spencer, J. R.; McKinnon, W. B.; Cruikshank, D. P.; White, O. L.; Umurhan, O. M.; Beyer, R. A.; Singer, K. N.; Schenk, P.; Stern, A.; Weaver, H. A., Jr.; Olkin, C.

2017-12-01

The New Horizons encounter with 2014 MU69 on 1 January 2019 will be the first small Kuiper belt object to be studied in detail from a spacecraft. The prospect that the cold classical population, which includes 2014 MU69, may represent a primordial, in situ population is exciting. Indeed, as we have learned just how complex and dynamic the early Solar System was, the cold classical population of the Kuiper belt has emerged as a singular candidate for a fundamentally unaltered original planetesimal population. MU69 in particular provides a unique opportunity to explore the disk processes and chemistry of the primordial solar nebula. As such, compositional measurements during the NH flyby are of paramount importance. So is high-resolution imaging of shape and structure, as the intermediate size of MU69 (much smaller than Pluto but much larger than a typical comet) may show signs of its accretion from much smaller bodies (layers, pebbles, lobes, etc., in the manner of 67P/C-G), or alternatively, derivation via the collisional fragmentation of a larger body if KBOs are "born big". MU69 may also be big enough to show signs of internal evolution driven by radiogenic heat from 26Al decay, if it accreted early enough and fast enough. The size of MU69 (20 - 40 km) places it in a class that has the potential to harbor unusual, and in some cases, possibly active, surface geological processes: several small satellites of similar size, including Helene and Epimetheus, display what appears to be fine-grained material covering large portions of their surfaces, and the surface of Phobos displays an unusual system of parallel grooves. Invariably, these intriguing surface features are only clearly defined at imaging resolutions of at least tens of meters per pixel. The best images of MU69 are planned to have resolutions of 20 - 40 m/pixel at a phase angle range of 40 - 70°. We also plan color imaging in 4 channels at 0.4 to 1 µ at 200 - 500 m/pixel, and 256 channel spectroscopy from 1.25 to 2.5 µ at 1 - 4 km/pixel. Ices such as H2O, NH3, CO2, and CH3OH would be stable and can be detected and mapped if they are exposed at the surface. It will be especially instructive to compare with Cassini VIMS spectra of Phoebe, thought to be a captured outer solar system planetesimal that formed in a related nebular environment to where MU69 formed.

Follow-up and Characterization of NEOs with the LCOGT Network

NASA Astrophysics Data System (ADS)

Lister, Tim

2013-10-01

Las Cumbres Observatory Global Telescope (LCOGT) network is a planned homogeneous network of over 35 telescopes at 6 locations in the northern and southern hemispheres. This network is versatile and designed to respond rapidly to target of opportunity events and also to do long term monitoring of slowly changing astronomical phenomena. The global coverage of the network and the apertures of telescope available make LCOGT ideal for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects (NEOs)) and ultimately for the discovery of new objects. LCOGT has completed the first phase of the deployment with the installation and commissioning of nine 1-meter telescopes at McDonald Observatory (Texas), Cerro Tololo (Chile), SAAO (South Africa) and Siding Spring Observatory (Australia). The telescope network is now operating and observations are being executed remotely and robotically. I am using the LCOGT network to confirm newly detected NEO candidates produced by the major sky surveys such as Catalina Sky Survey (CSS) and PanSTARRS (PS1). An increasing amount of time is being spent to obtain follow-up astrometry and photometry for radar-targeted objects in order to improve the orbits and determine the rotation periods. This will be extended to obtain more light curves of other NEOs which could be Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) or Asteroid Retrieval Mission (ARM) targets. Recent results have included the first period determination for the Apollo 2002 NV16 and our first NEO spectrum from the FLOYDS spectrographs on the LCOGT 2m telescopes obtained for 2012 DA14 during the February 2013 closepass.

Serpentinization and the Formation of H2 and CH4 on Celestial Bodies (Planets, Moons, Comets)

PubMed Central

Oze, C.; Mousis, O.; Waite, J.H.; Guilbert-Lepoutre, A.

2015-01-01

Abstract Serpentinization involves the hydrolysis and transformation of primary ferromagnesian minerals such as olivine ((Mg,Fe)2SiO4) and pyroxenes ((Mg,Fe)SiO3) to produce H2-rich fluids and a variety of secondary minerals over a wide range of environmental conditions. The continual and elevated production of H2 is capable of reducing carbon, thus initiating an inorganic pathway to produce organic compounds. The production of H2 and H2-dependent CH4 in serpentinization systems has received significant interdisciplinary interest, especially with regard to the abiotic synthesis of organic compounds and the origins and maintenance of life in Earth's lithosphere and elsewhere in the Universe. Here, serpentinization with an emphasis on the formation of H2 and CH4 are reviewed within the context of the mineralogy, temperature/pressure, and fluid/gas chemistry present in planetary environments. Whether deep in Earth's interior or in Kuiper Belt Objects in space, serpentinization is a feasible process to invoke as a means of producing astrobiologically indispensable H2 capable of reducing carbon to organic compounds. Key Words: Serpentinization—Fischer-Tropsch-type synthesis—Hydrogen formation—Methane formation—Ultramafic rocks. Astrobiology 15, 587–600. PMID:26154779

Deadly Sunflower Orbits

NASA Astrophysics Data System (ADS)

Hamilton, Douglas P.

2018-04-01

Solar radiation pressure is usually very effective at removing hazardous millimeter-sized debris from distant orbits around asteroidsand other small solar system bodies (Hamilton and Burns 1992). Theprimary loss mechanism, driven by the azimuthal component of radiationpressure, is eccentricity growth followed by a forced collision withthe central body. One large class of orbits, however, neatly sidestepsthis fate. Orbits oriented nearly perpendicular to the solar directioncan maintain their face-on geometry, oscillating slowly around a stableequilibrium orbit. These orbits, designated sunflower orbits, arerelated to terminator orbits studied by spacecraft mission designers(Broschart etal. 2014).Destabilization of sunflower orbits occurs only for particles smallenough that radiation pressure is some tens of percent the strength ofthe central body's direct gravity. This greatly enhanced stability,which follows from the inability of radiation incident normal to theorbit to efficiently drive eccentricities, presents a threat tospacecraft missions, as numerous dangerous projectiles are potentiallyretained in orbit. We have investigated sunflower orbits insupport of the New Horizons, Aida, and Lucy missions and find thatthese orbits are stable for hazardous particle sizes at asteroids,comets, and Kuiper belt objects of differing dimensions. Weinvestigate the sources and sinks for debris that might populate suchorbits, estimate timescales and equilibrium populations, and willreport on our findings.

Dynamical and collisional evolution of Halley-type comets

NASA Astrophysics Data System (ADS)

van der Helm, E.; Jeffers, S. V.

2012-03-01

The number of observed Halley-type comets is hundreds of times less than predicted by models (Levison, H.F., Dones, L., Duncan, M.J. [2001]. Astron. J. 121, 2253-2267). In this paper we investigate the impact of collisions with planetesimals on the evolution of Halley-type comets. First we compute the dynamical evolution of a sub-set of 21 comets using the MERCURY integrator package over 100 Myr. The dynamical lifetime is determined to be of the order of 105-106 years in agreement with previous work. The collisional probability of Halley-type comets colliding with known asteroids, a simulated population of Kuiper-belt objects, and planets, is calculated using a modified, Öpik-based collision code. Our results show that the catastrophic disruption of the cometary nucleus has a very low probability of occurring, and disruption through cumulative minor impacts is concluded to be negligible. The dust mantle formed from ejected material falling back to the comet’s surface is calculated to be less than a few centimeters thick, which is insignificant compared to the mantle formed by volatile depletion, while planetary encounters were found to be a negligible disruption mechanism.

KSC-05pd2648

NASA Image and Video Library

2005-12-07

KENNEDY SPACE CENTER, FLA. - A Florida quarter is prepared for installation on the New Horizons spacecraft in Kennedy Space Center's Payload Hazardous Servicing Facility. The new quarter, engraved with the "Gateway to Discovery" design, will accompany New Horizons on its 3-billion-mile journey to the planet Pluto and its moon, Charon. Although appropriate for the mission to carry the coin from the state that symbolizes space exploration, it will also serve a practical purpose: scientists are using the quarter as a spin-balance weight. New Horizons comprises seven scientific instruments that will characterize the global geology and geomorphology of Pluto and its moon Charon, map their surface compositions and temperatures, and examine Pluto's complex atmosphere. After that, flybys of Kuiper Belt objects from even farther in the solar system may be undertaken in an extended mission. New Horizons is the first mission in NASA's New Frontiers program of medium-class planetary missions. The spacecraft, designed for NASA by the Johns Hopkins University Applied Physics Laboratory in Laurel, Md., will launch aboard a Lockheed Martin Atlas V rocket and fly by Pluto and Charon as early as summer 2015. Photo Credit: Applied Physics Laboratory/George W. Rogers III

P/2006 HR30 (Siding Spring): A Low-activity Comet in Near-Earth Space

NASA Technical Reports Server (NTRS)

Hicks, Michael D.; Bauer, James M.

2007-01-01

The low cometary activity of P/2006 HR30 (Siding Spring) allowed a unique opportunity to study the nucleus of a periodic comet while near perihelion. P/2006 HR30 was originally targeted as a potential extinct comet, and we measured spectral reflectance and dust production using long-slit CCD spectroscopy and wide-field imaging obtained at the Palomar Mountain 200 inch telescope on 2006 August 3 and 4. The dust production Afp = 19.7 +/- 0.4 cm and mass-loss rate Q(dust) 4.1 +/- 0.1 kg/sec of the comet were approximately 2 orders of magnitude dust less than 1P/Halley at similar heliocentric distance. The VRI colors derived from the spectral reflectance were compared to Kuiper Belt objects, Centaurs, and other cometary nuclei. We found that the spectrum of P/2006 HR30 was consistent with other comets. However, the outer solar system bodies have a color distribution statistically distinct from cometary nuclei. It is our conjecture that cometary activity, most likely the reaccretion of ejected cometary dust, tends to moderate and mute the visible colors of the surface of cometary nuclei.

Dynamical evolution of a fictitious population of binary Neptune Trojans

NASA Astrophysics Data System (ADS)

Brunini, Adrián

2018-03-01

We present numerical simulations of the evolution of a synthetic population of Binary Neptune Trojans, under the influence of the solar perturbations and tidal friction (the so-called Kozai cycles and tidal friction evolution). Our model includes the dynamical influence of the four giant planets on the heliocentric orbit of the binary centre of mass. In this paper, we explore the evolution of initially tight binaries around the Neptune L4 Lagrange point. We found that the variation of the heliocentric orbital elements due to the libration around the Lagrange point introduces significant changes in the orbital evolution of the binaries. Collisional processes would not play a significant role in the dynamical evolution of Neptune Trojans. After 4.5 × 109 yr of evolution, ˜50 per cent of the synthetic systems end up separated as single objects, most of them with slow diurnal rotation rate. The final orbital distribution of the surviving binary systems is statistically similar to the one found for Kuiper Belt Binaries when collisional evolution is not included in the model. Systems composed by a primary and a small satellite are more fragile than the ones composed by components of similar sizes.

Dynamical Evolution Induced by Planet Nine

NASA Astrophysics Data System (ADS)

Batygin, Konstantin; Morbidelli, Alessandro

2017-12-01

The observational census of trans-Neptunian objects with semimajor axes greater than ˜ 250 {au} exhibits unexpected orbital structure that is most readily attributed to gravitational perturbations induced by a yet-undetected, massive planet. Although the capacity of this planet to (I) reproduce the observed clustering of distant orbits in physical space, (II) facilitate the dynamical detachment of their perihelia from Neptune, and (III) excite a population of long-period centaurs to extreme inclinations is well-established through numerical experiments, a coherent theoretical description of the dynamical mechanisms responsible for these effects remains elusive. In this work, we characterize the dynamical processes at play from semi-analytic grounds. We begin by considering a purely secular model of orbital evolution induced by Planet Nine and show that it is at odds with the ensuing stability of distant objects. Instead, the long-term survival of the clustered population of long-period Kuiper Belt objects (KBOs) is enabled by a web of mean-motion resonances driven by Planet Nine. Then, by taking a compact-form approach to perturbation theory, we show that it is the secular dynamics embedded within these resonances that regulate the orbital confinement and perihelion detachment of distant KBOs. Finally, we demonstrate that the onset of large-amplitude oscillations of the orbital inclinations is accomplished through the capture of low-inclination objects into a high-order secular resonance, and we identify the specific harmonic that drives the evolution. In light of the developed qualitative understanding of the governing dynamics, we offer an updated interpretation of the current observational data set within the broader theoretical framework of the Planet Nine hypothesis.

A GREAT search for Deuterium in Comets

NASA Astrophysics Data System (ADS)

Mumma, Michael

2012-10-01

Comets are understood to be the most pristine bodies in the Solar System. Their compositions reflect the chemical state of materials at the very earliest evolutionary stages of the protosolar nebula and, as such, they provide detailed insight into the physical and chemical processes operating in planet-forming disks. Isotopic fractionation ratios of the molecular ices in the nucleus are regarded as signatures of formation processes. These ratios provide unique information on the natal heritage of those ices, and can also test the proposal that Earth's water and other volatiles were delivered by cometary bombardment. Measurement of deuterium fractionation ratios is thus a major goal in contemporary cometary science and the D/H ratio of water - the dominant volatile in comets - holds great promise for testing the formation history of cometary matter. The D/H ratio in cometary water has been measured in only seven comets. Six were from the Oort Cloud reservoir and the D/H ratio was about twice that of the Earth's oceans. However, the recent Herschel measurement of HDO/H2O in 103P/Hartley-2 (the first from the Kuiper Belt) was consistent with exogenous delivery of Earth's water by comets. Outstanding questions remain: are cometary HDO/H2O ratios consistent with current theories of nebular chemical evolution or with an interstellar origin? Does the HDO/H2O ratio vary substantially among comet populations? Hartley-2 is the only Kuiper Belt comet with measured HDO/H2O, are there comets with similar ratios in the Oort cloud? These questions can only be addressed by measuring HDO/H2O ratios in many more suitable bright comets. We therefore propose to measure the D/H ratio in water in a suitable target-of-opportunity comet by performing observations of HDO and OH with the GREAT spectrometer on SOFIA. A multi-wavelength, ground-based observing campaign will also be conducted in support of the airborne observations.

A GREAT search for Deuterium in Comets

NASA Astrophysics Data System (ADS)

Mumma, Michael

2013-10-01

Comets are understood to be the most pristine bodies in the Solar System. Their compositions reflect the chemical state of materials at the very earliest evolutionary stages of the protosolar nebula and, as such, they provide detailed insight into the physical and chemical processes operating in planet-forming disks. Isotopic fractionation ratios of the molecular ices in the nucleus are regarded as signatures of formation processes. These ratios provide unique information on the natal heritage of those ices, and can also test the proposal that Earth's water and other volatiles were delivered by cometary bombardment. Measurement of deuterium fractionation ratios is thus a major goal in contemporary cometary science and the D/H ratio of water - the dominant volatile in comets - holds great promise for testing the formation history of cometary matter. The D/H ratio in cometary water has been measured in only eight comets. Seven were from the Oort Cloud reservoir and the D/H ratio was about twice that of the Earth's oceans. However, the recent Herschel measurement of HDO/H2O in 103P/Hartley-2 (the first from the Kuiper Belt) was consistent with exogenous delivery of Earth's water by comets. Outstanding questions remain: are cometary HDO/H2O ratios consistent with current theories of nebular chemical evolution or with an interstellar origin? Does the HDO/H2O ratio vary substantially among comet populations? Hartley-2 is the only Kuiper Belt comet with measured HDO/H2O, are there comets with similar ratios in the Oort cloud? These questions can only be addressed by measuring HDO/H2O ratios in many more suitable bright comets. We therefore propose to measure the D/H ratio in water in a suitable target-of-opportunity comet by performing observations of HDO and OH with the GREAT spectrometer on SOFIA. A multi-wavelength, ground-based observing campaign will also be conducted in support of the airborne observations.

The Evolution of Saturn's Rings Under the Influence of the Edgeworth-Kuiper Belt Micrometeoroid Flux: Tightening the Constraints on Ring Age

NASA Astrophysics Data System (ADS)

Estrada, Paul R.; Durisen, Richard H.; Cuzzi, Jeffrey N.

2016-10-01

Results of the Cassini Dust Analyzer (CDA) experiment indicate that the determined range of the micrometeoroid flux at infinity for Saturn (Altobelli et al., 2015) may be comparable to the nominal value of the incident, flat-plate and one-sided meteoroid flux value currently adopted for use in ballistic transport applications and models (e.g., Estrada et al., 2015). Moreover, the source of the micrometeoroid flux has been localized to the Edgeworth-Kuiper Belt (EKB) and is not cometary in origin as previously assumed. Apart from suggesting an altogether different composition for the ring pollutant, a major consequence of these new measurements is that the EKB flux is much more gravitationally focused than the cometary case because it is isotropic in the planet rather than the heliocentric frame. Thus, the lower velocities at infinity that characterize the EKB flux can increase the impact flux on the rings by a factor of ˜25. This means that even for the lower bound of the range of the newly measured flux, the amount of material hitting the rings may be considerably higher and thus the process of micrometeoroid bombardment and ballistic transport is likely even more influential in the rings' structural and compositional evolution over time. Here, we calculate the new EKB ejecta distribution using the model of Cuzzi and Durisen (1990) and compare this with the nominal cometary one, and then demonstrate using new simulations the consequences of the EKB flux on the evolution of ring composition and structure. The constraining of the micrometeoroid flux represents a very important step in being able to associate an absolute age for the rings. We argue that the new EKB flux poses a serious problem for "primordial" or "old" ring origin scenarios and favors more a scenario in which the rings, at least the way we see them today, cannot be much older than a few 100 Myrs.

Transit Spectroscopy: new data analysis techniques and interpretation

NASA Astrophysics Data System (ADS)

Tinetti, Giovanna; Waldmann, Ingo P.; Morello, Giuseppe; Tessenyi, Marcell; Varley, Ryan; Barton, Emma; Yurchenko, Sergey; Tennyson, Jonathan; Hollis, Morgan

2014-11-01

Planetary science beyond the boundaries of our Solar System is today in its infancy. Until a couple of decades ago, the detailed investigation of the planetary properties was restricted to objects orbiting inside the Kuiper Belt. Today, we cannot ignore that the number of known planets has increased by two orders of magnitude nor that these planets resemble anything but the objects present in our own Solar System. A key observable for planets is the chemical composition and state of their atmosphere. To date, two methods can be used to sound exoplanetary atmospheres: transit and eclipse spectroscopy, and direct imaging spectroscopy. Although the field of exoplanet spectroscopy has been very successful in past years, there are a few serious hurdles that need to be overcome to progress in this area: in particular instrument systematics are often difficult to disentangle from the signal, data are sparse and often not recorded simultaneously causing degeneracy of interpretation. We will present here new data analysis techniques and interpretation developed by the “ExoLights” team at UCL to address the above-mentioned issues. Said techniques include statistical tools, non-parametric, machine-learning algorithms, optimized radiative transfer models and spectroscopic line-lists. These new tools have been successfully applied to existing data recorded with space and ground instruments, shedding new light on our knowledge and understanding of these alien worlds.

ACS Imaging of beta Pic: Searching for the origin of rings and asymmetry in planetesimal disks

NASA Astrophysics Data System (ADS)

Kalas, Paul

2003-07-01

The emerging picture for planetesimal disks around main sequence stars is that their radial and azimuthal symmetries are significantly deformed by the dynamical effects of either planets interior to the disk, or stellar objects exterior to the disk. The cause of these structures, such as the 50 AU cutoff of our Kuiper Belt, remains mysterious. Structure in the beta Pic planetesimal disk could be due to dynamics controlled by an extrasolar planet, or by the tidal influence of a more massive object exterior to the disk. The hypothesis of an extrasolar planet causing the vertical deformation in the disk predicts a blue color to the disk perpendicular to the disk midplane. The hypothesis that a stellar perturber deforms the disk predicts a globally uniform color and the existence of ring-like structure beyond 800 AU radius. We propose to obtain deep, multi-color images of the beta Pic disk ansae in the region 15"-220" {200-4000 AU} radius with the ACS WFC. The unparalleled stability of the HST PSF means that these data are uniquely capable of delivering the color sensitivity that can distinguish between the two theories of beta Pic's disk structure. Ascertaining the cause of such structure provide a meaningful context for understanding the dynamical history of our early solar system, as well as other planetesimal systems imaged around main sequence stars.

Observational Constraints on the Orbit and Location of Planet Nine in the Outer Solar System

NASA Astrophysics Data System (ADS)

Brown, Michael E.; Batygin, Konstantin

2016-06-01

We use an extensive suite of numerical simulations to constrain the mass and orbit of Planet Nine, the recently proposed perturber in a distant eccentric orbit in the outer solar system. We compare our simulations to the observed population of aligned eccentric high semimajor axis Kuiper belt objects (KBOs) and determine which simulation parameters are statistically compatible with the observations. We find that only a narrow range of orbital elements can reproduce the observations. In particular, the combination of semimajor axis, eccentricity, and mass of Planet Nine strongly dictates the semimajor axis range of the orbital confinement of the distant eccentric KBOs. Allowed orbits, which confine KBOs with semimajor axis beyond 380 au, have perihelia roughly between 150 and 350 au, semimajor axes between 380 and 980 au, and masses between 5 and 20 Earth masses. Orbitally confined objects also generally have orbital planes similar to that of the planet, suggesting that the planet is inclined approximately 30°to the ecliptic. We compare the allowed orbital positions and estimated brightness of Planet Nine to previous and ongoing surveys which would be sensitive to the planet’s detection and use these surveys to rule out approximately two-thirds of the planet’s orbit. Planet Nine is likely near aphelion with an approximate brightness of 22< V< 25. At opposition, its motion, mainly due to parallax, can easily be detected within 24 hours.

Reanalyzing the visible colors of Centaurs and KBOs: what is there and what we might be missing

NASA Astrophysics Data System (ADS)

Peixinho, Nuno; Delsanti, Audrey; Doressoundiram, Alain

2015-05-01

Since the discovery of the Kuiper belt, broadband surface colors were thoroughly studied as a first approximation to the object reflectivity spectra. Visible colors (BVRI) have proven to be a reasonable proxy for real spectra, which are rather linear in this range. In contrast, near-IR colors (JHK bands) could be misleading when absorption features of ices are present in the spectra. Although the physical and chemical information provided by colors are rather limited, broadband photometry remains the best tool for establishing the bulk surface properties of Kuiper belt objects (KBOs) and Centaurs. In this work, we explore for the first time general, recurrent effects in the study of visible colors that could affect the interpretation of the scientific results: i) how a correlation could be missed or weakened as a result of the data error bars; ii) the "risk" of missing an existing trend because of low sampling, and the possibility of making quantified predictions on the sample size needed to detect a trend at a given significance level - assuming the sample is unbiased; iii) the use of partial correlations to distinguish the mutual effect of two or more (physical) parameters; and iv) the sensitivity of the "reddening line" tool to the central wavelength of the filters used. To illustrate and apply these new tools, we have compiled the visible colors and orbital parameters of about 370 objects available in the literature - assumed, by default, as unbiased samples - and carried out a traditional analysis per dynamical family. Our results show in particular how a) data error bars impose a limit on the detectable correlations regardless of sample size and that therefore, once that limit is achieved, it is important to diminish the error bars, but it is pointless to enlarge the sampling with the same or larger errors; b) almost all dynamical families still require larger samplings to ensure the detection of correlations stronger than ±0.5, that is, correlations that may explain ~25% or more of the color variability; c) the correlation strength between (V - R) vs. (R - I) is systematically lower than the one between (B - V) vs. (V - R) and is not related with error-bar differences between these colors; d) it is statistically equivalent to use any of the different flavors of orbital excitation or collisional velocity parameters regarding the famous color-inclination correlation among classical KBOs - which no longer appears to be a strong correlation - whereas the inclination and Tisserand parameter relative to Neptune cannot be separated from one another; and e) classical KBOs are the only dynamical family that shows neither (B - V) vs. (V - R) nor (V - R) vs. (R - I) correlations. It therefore is the family with the most unpredictable visible surface reflectivities. Tables 4 and 5 are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/577/A35

Exploring the story, science, and adventure of small worlds

NASA Astrophysics Data System (ADS)

Swann, J. L.; Elkins-Tanton, L. T.; Anbar, A. D.; Klug Boonstra, S.; Tamer, A. J.; Mead, C.; Hunsley, D.

2017-12-01

Small worlds are a strategic focus at NASA, reflected by missions such as Osiris Rex and Psyche among others. The Infiniscope project, with funding from NASA SMD, is building on this scientific and public interest to teach formal and informal learners about asteroids and other small worlds. The digital learning experience, "Where are the small worlds?", and future Infiniscope experiences, incorporate a design theory that we describe as "education through exploration" (ETX) which is provided through an adaptive e-learning platform. This design ensures that learners actively engage in exploration and discovery, while receiving targeted feedback to push through challenges. To ensure that this and future experiences reach and meet the needs of as many educators as possible, Infiniscope includes a digital teaching network to host the experiences and support the reuse and adaptation of digital resources in new lessons. "Where are the small worlds?" puts learners in an interactive simulation of the solar system and provides a mission structure in which they hunt for "astrocaches" on near earth objects, main belt asteroids, and Kuiper-belt objects. These activities allow the learner to discover the locations of the small worlds in the solar system and develop an intuitive understanding for the relative motion of objects at various distances from the Sun. The experience is NGSS-aligned and accompanied by a lesson plan for integration into the classroom. In testing with more than 500 middle-school students, 83% of participants said they wanted to do more experiences like "Where are the small worlds?" They also found the experience both "fun" and "interesting" while being moderately difficult. "Where are the small worlds?" is one of many visualizations and lessons that is available within the Infiniscope teaching network. The network already has hundreds of members and is expected to grow in both numbers and engagement over time. Currently, educators can search and use pre-existing experiences, but as the visualization library expands and educators learn more about exploration-learning design, they may modify existing experiences and even build entirely new experiences to meet specific needs. In parallel, we are also developing a professional development program that builds understanding of the principles of ETX design.

Mercury: Photomosaic of the Kuiper Quadrangle H-6

NASA Image and Video Library

2000-01-19

The Kuiper Quadrangle was named in memory of Dr. Gerard Kuiper, an imaging team member, and well-known astronomer, of NASA Mariner 10 Venus/Mercury. The Kuiper crater is seen left of center in this image.

The LCOGT Network for Solar System Science

NASA Astrophysics Data System (ADS)

Lister, Tim

2012-10-01

Las Cumbres Observatory Global Telescope (LCOGT) network is a planned homogeneous network of over 35 telescopes at 6 locations in the northern and southern hemispheres. This network is versatile and designed to respond rapidly to target of opportunity events and also to do long term monitoring of slowly changing astronomical phenomena. The global coverage of the network and the apertures of telescope available make LCOGT ideal for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects (NEOs)) and ultimately for the discovery of new objects. Currently LCOGT is operating the two 2m Faulkes Telescopes at Haleakala, Maui and Siding Spring Observatory, Australia and in March 2012 completed the install of the first member of the new 1m telescope network at McDonald Observatory, Texas. Further deployments of six to eight 1m telescopes to CTIO in Chile, SAAO in South Africa and Siding Spring Observatory are expected in late 2012-early 2013. I am using the growing LCOGT network to confirm newly detected NEO candidates produced by PanSTARRS (PS1) and other sky surveys and to obtain follow-up astrometry and photometry for radar-targeted objects. I have developed an automated system to retrieve new PS1 NEOs, compute orbits, plan observations and automatically schedule them for follow-up on the robotic telescopes of the LCOGT Network. In the future, LCOGT has proposed to develop a Minor Planet Investigation Project (MPIP) that will address the existing lack of resources for minor planet follow-up, takes advantage of ever-increasing new datasets, and develops a platform for broad public participation in relevant scientific exploration. We plan to produce a cloud-based Solar System investigation environment, a citizen science project (AgentNEO), and a cyberlearning environment, all under the umbrella of MPIP.

SMACK: A New Algorithm for Modeling Collisions and Dynamics of Planetesimals in Debris Disks

NASA Technical Reports Server (NTRS)

Nesvold, Erika Rose; Kuchner, Marc J.; Rein, Hanno; Pan, Margaret

2013-01-01

We present the Superparticle Model/Algorithm for Collisions in Kuiper belts and debris disks (SMACK), a new method for simultaneously modeling, in 3-D, the collisional and dynamical evolution of planetesimals in a debris disk with planets. SMACK can simulate azimuthal asymmetries and how these asymmetries evolve over time. We show that SMACK is stable to numerical viscosity and numerical heating over 10(exp 7) yr, and that it can reproduce analytic models of disk evolution. We use SMACK to model the evolution of a debris ring containing a planet on an eccentric orbit. Differential precession creates a spiral structure as the ring evolves, but collisions subsequently break up the spiral, leaving a narrower eccentric ring.

Inadvertent Earth Reentry Breakup Analysis for the New Horizons Mission

NASA Technical Reports Server (NTRS)

Ling, Lisa M.; Salama, Ahmed; Ivanov, Mark; McRonald, Angus

2007-01-01

The New Horizons (NH) spacecraft was launched in January 2006 aboard an Atlas V launch vehicle, in a mission to explore Pluto, its moons, and other bodies in the Kuiper Belt. The NH spacecraft is powered by a Radioisotope Thermoelectric Generator (RTG) which encases multiple General Purpose Heat Source (GPHS) modules. Thus, a pre-launch vehicle breakup analysis for an inadvertent atmospheric reentry in the event of a launch failure was required to assess aerospace nuclear safety and for launch contingency planning. This paper addresses potential accidental Earth reentries analyzed at the Jet Propulsion Laboratory (JPL) which may arise during the ascent to parking orbit, resulting in a suborbital reentry, as well as a departure from parking orbit, resulting in an orbital reentry.

A Herschel-Detected Correlation between Planets and Debris Disks

NASA Astrophysics Data System (ADS)

Bryden, Geoffrey; Krist, J. E.; Stapelfeldt, K. R.; Kennedy, G.; Wyatt, M.; Beichman, C. A.; Eiroa, C.; Marshall, J.; Maldonado, J.; Montesinos, B.; Moro-Martin, A.; Matthews, B. C.; Fischer, D.; Ardila, D. R.; Kospal, A.; Rieke, G.; Su, K. Y.

2013-01-01

The Fomalhaut, beta Pic, and HR 8799 systems each have directly imaged planets and prominent debris disks, suggesting a direct link between the two phenomena. Unbiased surveys with Spitzer, however, failed to find a statistically significant correlation. We present results from SKARPS (the Search for Kuiper belts Around Radial-velocity Planet Stars) a Herschel far-IR survey for debris disks around solar-type stars known to have orbiting planets. The identified disks are generally cold and distant 50 K/100 AU), i.e. well separated from the radial-velocity-discovered planets. Nevertheless, we find a strong correlation between the inner planets and outer disks, with disks around planet-bearing stars tending to be much brighter than those not known to have planets.

Mission Steering Profiles of Outer Planetary Orbiters Using Radioisotope Electric Propulsion

NASA Technical Reports Server (NTRS)

Fiehler, Douglas; Oleson, Steven

2004-01-01

Radioisotope Electric Propulsion (REP) has the potential to enable small spacecraft to orbit outer planetary targets with trip times comparable to flyby missions. The ability to transition from a flyby to an orbiter mission lies in the availability of continuous low power electric propulsion along the entire trajectory. The electric propulsion system s role is to add and remove energy from the spacecraft s trajectory to bring it in and out of a heliocentric hyperbolic escape trajectory for the outermost target bodies. Energy is added and the trajectory is reshaped to rendezvous with the closer-in target bodies. Sample REP trajectories will be presented for missions ranging for distances from Jupiter orbit to the Pluto-Kuiper Belt.

Dust in the Outer Solar System as measured by Cassini-CDA: KBOs, Centaurs and TNOs as parent bodies?

NASA Astrophysics Data System (ADS)

Altobelli, N.; Kempf, S.; Srama, R.

2017-09-01

We analyse 13 years of data acquired by the Cosmic Dust Analyser (CDA)-Entrance Grid (EG) subsystem on-board the Cassini spacecraft around Saturn. We confirm the presence of exogenous dust, originating from the interplanetary space and permanently crossing the Saturnian system. We analyse the range of possible heliocentric orbital elements in order to identify their possible origin. We observe particles whose dynamics is compatible with 'old' collisional debris from the Kuiper-Belt, migrating inward the Solar System under influence of the Poynting-Robertson drag, or relatively fresh grains from recently discovered cometary activity of Centaurs. A population of particles entering the Saturn's system with high velocities can be linked to Halley-type comets as parent bodies.

OSSOS. VII. 800+ Trans-Neptunian Objects—The Complete Data Release

NASA Astrophysics Data System (ADS)

Bannister, Michele T.; Gladman, Brett J.; Kavelaars, J. J.; Petit, Jean-Marc; Volk, Kathryn; Chen, Ying-Tung; Alexandersen, Mike; Gwyn, Stephen D. J.; Schwamb, Megan E.; Ashton, Edward; Benecchi, Susan D.; Cabral, Nahuel; Dawson, Rebekah I.; Delsanti, Audrey; Fraser, Wesley C.; Granvik, Mikael; Greenstreet, Sarah; Guilbert-Lepoutre, Aurélie; Ip, Wing-Huen; Jakubik, Marian; Jones, R. Lynne; Kaib, Nathan A.; Lacerda, Pedro; Van Laerhoven, Christa; Lawler, Samantha; Lehner, Matthew J.; Lin, Hsing Wen; Lykawka, Patryk Sofia; Marsset, Michaël; Murray-Clay, Ruth; Pike, Rosemary E.; Rousselot, Philippe; Shankman, Cory; Thirouin, Audrey; Vernazza, Pierre; Wang, Shiang-Yu

2018-05-01

The Outer Solar System Origins Survey (OSSOS), a wide-field imaging program in 2013–2017 with the Canada–France–Hawaii Telescope, surveyed 155 deg2 of sky to depths of m r = 24.1–25.2. We present 838 outer solar system discoveries that are entirely free of ephemeris bias. This increases the inventory of trans-Neptunian objects (TNOs) with accurately known orbits by nearly 50%. Each minor planet has 20–60 Gaia/Pan-STARRS-calibrated astrometric measurements made over 2–5 oppositions, which allows accurate classification of their orbits within the trans-Neptunian dynamical populations. The populations orbiting in mean-motion resonance with Neptune are key to understanding Neptune’s early migration. Our 313 resonant TNOs, including 132 plutinos, triple the available characterized sample and include new occupancy of distant resonances out to semimajor axis a ∼ 130 au. OSSOS doubles the known population of the nonresonant Kuiper Belt, providing 436 TNOs in this region, all with exceptionally high-quality orbits of a uncertainty σ a ≤ 0.1% they show that the belt exists from a ≳ 37 au, with a lower perihelion bound of 35 au. We confirm the presence of a concentrated low-inclination a ≃ 44 au “kernel” population and a dynamically cold population extending beyond the 2:1 resonance. We finely quantify the survey’s observational biases. Our survey simulator provides a straightforward way to impose these biases on models of the trans-Neptunian orbit distributions, allowing statistical comparison to the discoveries. The OSSOS TNOs, unprecedented in their orbital precision for the size of the sample, are ideal for testing concepts of the history of giant planet migration in the solar system.

Photometry of Galactic and Extragalactic Far-Infrared Sources using the 91.5 cm Airborne Infrared Telescope

NASA Technical Reports Server (NTRS)

Harper, D. A.

1996-01-01

The objective of this grant was to construct a series of far infrared photometers, cameras, and supporting systems for use in astronomical observations in the Kuiper Airborne Observatory. The observations have included studies of galaxies, star formation regions, and objects within the Solar System.

The prevalence of resonances among large-a transneptunian objects

NASA Astrophysics Data System (ADS)

Gladman, Brett; Volk, Kathryn; Van Laerhoven, Christa

2018-04-01

The detached population consists of transneptunian objects (TNOs) with large semi-major axes and sufficiently high perihelia (roughly q>38 au, but there is no simple cut). However, what constitutes 'large semi-major axis' has been, and continues to be, unclear. Once beyond the apehlia of the classical Kuiper Belt (which extends out to about 60 au), objects with semimajor axes from a=60-150 au can be detached, but there are a reasonable number of objects in this range known to be in mean-motion resonances with Neptune. Beyond a=150 au, however, it is a widely-held belief that resonances become `unimportant', and that a q>38 au cut (or sometimes q>50 au) with a>150 au isolates a set of large semimajor axis detached objects. However, once semimajor axes become this large, the orbit determination of the object discovered near perihelion becomes a much harder task then for low-a TNOs. Because small velocity differences near the perihelion of large-a orbits cause large changes the fitted orbital in semimajor axis, extremely good and long baseline astrometry is required to reduce the semimajor axis uncertainty to be smaller than the few tenths of an astronomical unit widths of mean motion resonances. By carefully analyzing the astrometric data of all known large semimajor axis objects, we show that a very large fraction of the objects are in fact likely in high-order mean-motion resonances with Neptune. This prevealence for actually being resonant with Neptune would imply that hypothesized planets are problematic as they would remove the detached objects from these resonances. Instead, we favor a view in which the large-a population is the surviving remnant of a massive early scattering disk, whose surviving members are sculpted mostly by diffusive gravitational interactions with the four giant planets over the last four gigayears, but whose initial emplacement mechanism (in particular: perihelion lifting mechanism) is still unclear but of critical importance to the early Solar System's evolution.

Detection of CO and HCN in the coma of Jupiter-family comet 41P/Tuttle-Giacobini-Kresak

NASA Astrophysics Data System (ADS)

Wierzchos, Kacper; Womack, Maria

2017-10-01

Comets are divided into taxonomical groups determined largely by their orbits. Short-period Jupiter Family comets (JFCs) are thought to have formed in a trans-Neptunian disk ˜30 - 100 AU (Kuiper Belt) and then migrated inward (Edgeworth 1949, Kuiper 1951, Duncan et al. 1988). This different classification may be correlated with chemical abundance variations, and super-volatile species like CO can serve as an indicator of the thermal processes to which the precometary ices that led to comets where exposed (DiSainti et al. 2007). The close approach to Earth of comet 41P on the perihelion passage of 2017 was an excellent opportunity to probe the usually well-hidden inner coma of this Jupiter-family comet. We searched for CO (J=2-1) and HCN (J=3-2) emission with the Arizona Radio Observatory (ARO) 10-m Sub-millimeter Telescope (SMT) on 2017 April 1-2, when the comet was 1.1 AU from the Sun and 0.14 AU from Earth. We report the detection of both CO and HCN emission 13 days before perihelion and present column densities and production rates. We also discuss implications for Jupiter-family comets. The SMT is operated by the ARO, the Steward Observatory, and the University of Arizona, with support through the NSF University Radio Observatories program (AST-1140030). M.W. acknowledges support from NSF grant AST-1615917.

Binaries in Transneptunian Resonances: Evidence for Slow Migration of Neptune?

NASA Technical Reports Server (NTRS)

Noll, Keith

2012-01-01

A distinguishing feature of trans neptunian objects (TNO) is the high fraction that arc binary. This is particularly true for the Cold Classicals (CC), objects in lowe and low i orbits concentrated between the 3:2 and 2: 1 mean-motion resonances. CCs have other physical markers: red colors, high albedos, and equal-mass binaries. The CCs appear to be a coherent and physically distinct population of planetesimals that has survived to the present with their physical properties relatively unaltered. Their spatial concentration between 39.4 and 47.7 AU has made identification of the CCs as a physical group possible. However, objects that started out as CCs arc almost certainly 1101 limited to this one dynamical niche. We can, therefore, use the measurable physical properties of CCs as tracers of Neptune-driven dynamical mixing in the Kuiper Belt. As Neptune migrated, its mean-motion resonances preceded it into the planetesimal disk. The efficiency of capture into mean motion resonances depends on the smoothness of Neptune's migration and the local population available to be captured. The two strongest resonances, the 3:2 at 39.4 AU and 2: 1 at 47.7 AU, straddle the core repository of the physically distinct CCs, providing a unique opportunity to test the details of Neptune's migration. Smooth migration should result in a measurable difference between the 3:2 and 2:1 with low inclination 2:1s having a red, binary population mirroring that of the CC itself while the 3:2 will be less contaminated. Alternative models with rapid migration would generate a more homogeneous result.

(abstract) Follow-on Missions for the Pluto Spacecraft

NASA Technical Reports Server (NTRS)

Weinstein, Stacy; Salvo, Chris; Stern, Alan

1994-01-01

The Pluto Fast Flyby mission development baseline consists of 2 identical spacecraft (120 - 165 kg) to be launched to Pluto/Charon in the late 1990s. These spacecraft are intended to fly by Pluto and Charon in order to perform various remote-sensing scientific investigations and have a mission development cost less than $400M (FY92$) through launch plus 30 days. The long-life (6 - 10 years) mission duration and lightweight design make the Pluto spacecraft a good candidate for a number of other flyby missions to objects in the outer Solar System, and some of these were investigated by JPL in cooperation with NASA Code SL's (Solar System Exploration) Outer Planets Science Working Group (OPSWG) in 1993. The JPL team looked at what it would mean to fly one of these missions (if a third spacecraft were available) in terms of flight time, spacecraft modifications, and science payload resources; the OPSWG recommended science investigation modifications for the different targets based on the available resources. The missions could, in many cases, utilize less capable launch vehicles, thereby reducing life-cycle cost of the mission. Examples of the sort of targets which were investigated and looked attractive in terms of flight time are: Uranus, Neptune, Uranus/Neptune dual-mission, Trojan asteroids (624 Hektor, 617 Patroclus, others), 5145 Pholus (the reddest object known in the solar system), and Kuiper Belt objects (i.e., 1992 QB1) . This paper will present the results of this investigation in terms of potential science return, performance, and the potential for life-cycle cost reductions through inheritance from Pluto Fast Flyby .

A HYPOTHESIS FOR THE COLOR BIMODALITY OF JUPITER TROJANS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wong, Ian; Brown, Michael E., E-mail: iwong@caltech.edu

One of the most enigmatic and hitherto unexplained properties of Jupiter Trojans is their bimodal color distribution. This bimodality is indicative of two sub-populations within the Trojans, which have distinct size distributions. In this paper, we present a simple, plausible hypothesis for the origin and evolution of the two Trojan color sub-populations. In the framework of dynamical instability models of early solar system evolution, which suggest a common primordial progenitor population for both Trojans and Kuiper Belt objects, we use observational constraints to assert that the color bimodalities evident in both minor body populations developed within the primordial population priormore » to the onset of instability. We show that, beginning with an initial composition of rock and ices, location-dependent volatile loss through sublimation in this primordial population could have led to sharp changes in the surface composition with heliocentric distance. We propose that the depletion or retention of H{sub 2}S ice on the surface of these objects was the key factor in creating an initial color bimodality. Objects that retained H{sub 2}S on their surfaces developed characteristically redder colors upon irradiation than those that did not. After the bodies from the primordial population were scattered and emplaced into their current positions, they preserved this primordial color bimodality to the present day. We explore predictions of the volatile loss model—in particular, the effect of collisions within the Trojan population on the size distributions of the two sub-populations—and propose further experimental and observational tests of our hypothesis.« less

Where are Sedna's Sisters?

NASA Astrophysics Data System (ADS)

Bartlett, D. F.

2005-05-01

Simulations of the formation of the Oort cloud from the Kuiper Belt typically are presented as an animated scatter diagram. Here the orbit of each object appears as a point of perihelion distance q and semi-major axis a. (eg. Levison, Morbidelli, & Dones 2004). These plots show a conspicuous void, bounded by the inequalities: q < a, q > 50 AU, and a < 5000-10000 AU. Brown (2005) calls this void the ``Bermuda Triangle". The only present occupant is Sedna (q=76 AU, a=501 AU). Brown, Trujillo, & Rabinowitz , the discovers of Sedna, have challenged others to explain how Sedna got inside the triangle and to predict where similar objects might be found. Sedna could not have simply formed in its current orbit by the accumulation of smaller objects (Stern 2005). Several authors have suggested that a passing star scattered Sedna into the triangle shortly after the birth of the solar system. Here I offer an alternative which uses the very strong galactic tidal forces of the Sinusoidal potential (Bartlett 2001, 2004). In this potential, the numerator of Newton's law is replaced by GM cos(ko r) where ko = 2 π / lambdao and the 'wavelength' λ o is 425 pc. The 20 radial oscillations between the sun and the center of the Galaxy give tidal forces that are 120 times as big as generally expected. I will show how this tidal force, acting over the lifetime of the solar system, could move the perihelion of Sedna from about 40 to 76 AU. Sedna's sisters are likely to have still larger q & a and to have perihelia in two specific quadrants of the ecliptic plane.

The structure of the distant Kuiper belt in a Nice model scenario

NASA Astrophysics Data System (ADS)

Pike, Rosemary E.; Lawler, Samantha; Brasser, Ramon; Shankman, Cory; Alexandersen, Mike; Kavelaars, J. J.

2016-10-01

By utilizing a well-sampled migration model and characterized survey detections, we demonstrate that the Nice-model scenario results in consistent populations of scattering trans-Neptunian objects (TNOs) and several resonant TNO populations, but fails to reproduce the large population of 5:1 resonators discovered in surveys. We examine in detail the TNO populations implanted by the Nice model simulation from Brasser and Morbidelli (2013, B&M). This analysis focuses on the region from 25-155 AU, probing the classical, scattering, detached, and major resonant populations. Additional integrations were necessary to classify the test particles and determine population sizes and characteristics. The classified simulation objects are compared to the real TNOs from the Canada-France Ecliptic Plane Survey (CFEPS), CFEPS high latitude fields, and the Alexandersen (2016) survey. These surveys all include a detailed characterization of survey depth, pointing, and tracking efficiency, which allows detailed testing of this independently produced model of TNO populations. In the B&M model, the regions of the outer Solar System populated via capture of scattering objects are consistent with survey constraints. The scattering TNOs and most n:1 resonant populations have consistent orbital distributions and population sizes with the real detections, as well as a starting disk mass consistent with expectations. The B&M 5:1 resonators have a consistent orbital distribution with the real detections and previous models. However, the B&M 5:1 Neptune resonance is underpopulated by a factor of ~100 and would require a starting proto-planetesimal disk with a mass of ~100 Earth masses. The large population in the 5:1 Neptune resonance is unexplained by scattering capture in a Nice-model scenario, however this model accurately produces the TNO subpopulations that result from scattering object capture and provides additional insight into sub-population orbital distributions.

The Sensitivity to Trans-Neptunian Dwarf Planets of the Siding Spring Survey

NASA Astrophysics Data System (ADS)

Bannister, Michele; Brown, M. E.; Schmidt, B. P.; Francis, P.; McNaught, R.; Garrad, G.; Larson, S.; Beshore, E.

2012-10-01

The last decade has seen considerable effort in assessing the populations of icy worlds in the outer Solar System, with major surveys in the Northern and more recently, in the Southern Hemisphere skies. Our archival search of more than ten thousand square degrees of sky south of the ecliptic observed over five years is a bright-object survey, sensitive to dwarf-planet sized trans-Neptunian objects. Our innovative survey analyses observations of the Siding Spring Survey, an ongoing survey for near-Earth asteroids at the 0.5 m Uppsala telescope at Siding Spring Observatory. This survey observed each of 2300 4.55 square degree fields on between 30 and 90 of the nights from early 2004 to late 2009, creating a dataset with dense temporal coverage, which we reprocessed for TNOs with a dedicated pipeline. We assess our survey's sensitivity to trans-Neptunian objects by simulating the observation of the synthetic outer Solar System populations of Grav et al. (2011): Centaurs, Kuiper belt and scattered disk. As our fields span approx. -15 to -70 declination, avoiding the galactic plane by 10 degrees either side, we are particularly sensitive to dwarf planets in high-inclination orbits. Partly due to this coverage far from the ecliptic, all known dwarf planets, including Pluto, do fall outside our survey coverage in its temporal span. We apply the widest plausible range of absolute magnitudes to each observable synthetic object, measuring each subsequent apparent magnitude against the magnitude depth of the survey observations. We evaluate our survey's null detection of new dwarf planets in light of our detection efficiencies as a function of trans-Neptunian orbital parameter space. MTB appreciates the funding support of the Joan Duffield Postgraduate Scholarship, an Australian Postgraduate Award, and the Astronomical Society of Australia.

The Research and Education Collaborative Occultation Network: A System for Coordinated TNO Occultation Observations

NASA Astrophysics Data System (ADS)

Buie, Marc W.; Keller, John M.

2016-03-01

We describe a new system and method for collecting coordinated occultation observations of trans-Neptunian objects (TNOs). Occultations by objects in the outer solar system are more difficult to predict due to their large distance and limited span of the astrometric data used to determine their orbits and positions. This project brings together the research and educational community into a unique citizen-science partnership to overcome the difficulties of observing these distant objects. The goal of the project is to get sizes and shapes for TNOs with diameters larger than 100 km. As a result of the system design it will also serve as a probe for binary systems with spatial separations as small as contact systems. Traditional occultation efforts strive to get a prediction sufficiently good to place mobile ground stations in the shadow track. Our system takes a new approach of setting up a large number of fixed observing stations and letting the shadows come to the network. The nominal spacing of the stations is 50 km so that we ensure two chords at our limiting size. The spread of the network is roughly 2000 km along a roughly north-south line in the western United States. The network contains 56 stations that are committed to the project and we get additional ad hoc support from International Occultation Timing Association members. At our minimum size, two stations will record an event while the other stations will be probing the inner regions for secondary events. Larger objects will get more chords and will allow determination of shape profiles. The stations are almost exclusively sited and associated with schools, usually at the 9-12 grade level. We present a full description of the system we have developed for the continued exploration of the Kuiper Belt.

Debris Disks as Tracers of Nearby Planetary Systems

NASA Technical Reports Server (NTRS)

Stapelfeldt, Karl

2012-01-01

Many main-sequence stars possess tenuous circumstellar dust clouds believed to trace extrasolar analogs of the Sun's asteroid and Kuiper Belts. While most of these "debris disks" are known only from far-infrared photometry, dozens are now spatially resolved. In this talk, I'll review the observed structural properties of debris disks as revealed by imaging with the Hubble, Spitzer, and Herschel Space Telescopes. I will show how modeling of the far-infrared spectral energy distributions of resolved disks can be used to constrain their dust particle sizes and albedos. I will review cases of disks whose substructures suggest planetary perturbations, including a newly-discovered eccentric ring system. I'll conclude with thoughts on the potential of upcoming and proposed facilities to resolve similar structures around a greatly expanded sample of nearby debris systems.

Constraints on the formation age of cometary material from the NASA Stardust mission.

PubMed

Matzel, J E P; Ishii, H A; Joswiak, D; Hutcheon, I D; Bradley, J P; Brownlee, D; Weber, P K; Teslich, N; Matrajt, G; McKeegan, K D; MacPherson, G J

2010-04-23

We measured the 26Al-26Mg isotope systematics of a approximately 5-micrometer refractory particle, Coki, returned from comet 81P/Wild 2 in order to relate the time scales of formation of cometary inclusions to their meteoritic counterparts. The data show no evidence of radiogenic 26Mg and define an upper limit to the abundance of 26Al at the time of particle formation: 26Al/27Al < 1 x 10(-5). The absence of 26Al indicates that Coki formed >1.7 million years after the oldest solids in the solar system, calcium- and aluminum-rich inclusions (CAIs). The data suggest that high-temperature inner solar system material formed, was subsequently transferred to the Kuiper Belt, and was incorporated into comets several million years after CAI formation.

Family Portrait of Pluto Moons

NASA Image and Video Library

2015-10-23

This composite image shows a sliver of Pluto large moon, Charon, and all four of Pluto small moons, as resolved by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft. All the moons are displayed with a common intensity stretch and spatial scale (see scale bar). Charon is by far the largest of Pluto's moons, with a diameter of 751 miles (1,212 kilometers). Nix and Hydra have comparable sizes, approximately 25 miles (40 kilometers) across in their longest dimension above. Kerberos and Styx are much smaller and have comparable sizes, roughly 6-7 miles (10-12 kilometers) across in their longest dimension. All four small moons have highly elongated shapes, a characteristic thought to be typical of small bodies in the Kuiper Belt. http://photojournal.jpl.nasa.gov/catalog/PIA20033

Panel proposes solar system missions

NASA Astrophysics Data System (ADS)

Showstack, Randy

A proposed probe to the Kuiper Belt and Pluto and another to Europa are among the priority Solar System exploration missions that should be pursued by NASA over the next decade, according to an 11 July report by a steering group of the Space Studies Board of the U.S. National Research Council (NRC).The report, "New Frontiers in the Solar System: An Integrated Exploration Strategy," was requested by NASA, and proposes a set of new missions and facilities to respond to key questions in four cross-cutting themes. The themes, which the report indicates form the basis for an integrated space exploration strategy are: the first billion years of Solar System history; volatiles and organics: the stuff of life; the origin and evolution of habitable worlds; and processes: how planets work.

Space Science Outreach in the Virtual World of Second Life

NASA Astrophysics Data System (ADS)

Crider, Anthony W.; International Spaceflight Museum

2006-12-01

The on-line "game" of Second Life allows users to construct a highly detailed and customized environment. Users often pool talents and resources to construct virtual islands that focus on their common interest. One such group has built the International Spaceflight Museum, committed to constructing and displaying accurate models of rockets, spacecraft, telescopes, and planetariums. Current exhibits include a Saturn V rocket, a Viking lander on Mars, Spaceship One, the New Horizons mission to the Kuiper Belt, and a prototype of the Orion crew exploration vehicle. This museum also hosts public lectures, shuttle launch viewings, and university astronomy class projects. In this presentation, I will focus on how space science researchers and educators may take advantage of this new resource as a means to engage the public.

The UV reflectance of Patroclus: Exploring the surface composition and origins of Jupiter Trojans

NASA Astrophysics Data System (ADS)

Molyneux, Pippa

2017-08-01

(617) Patroclus is a binary system comprising two almost equally sized Trojan asteroids, Patroclus and Menoetius. (617) Patroclus has never been observed in the UV spectral region, which contains important diagnostic features of major Trojan surface constituents inferred from fits to visible-near IR spectra. Previous spectral observations have not been spatially resolved, precluding a direct spectral comparison of the two bodies. We propose to obtain full surface UV reflectance maps of both Patroclus and Menoetius using the STIS G230L mode, to search for characteristic absorption features of silicates, carbons/graphites and NH3, which together make up the major inferred Jupiter Trojan surface constituents, and for signs of ''spectral bluing'' that occurs for space-weathered objects. The Jupiter Trojans are believed to represent the most readily accessible Kuiper Belt material in the solar system, having been scattered from that region to their current orbits following a dynamical instability. A direct spectral comparison of Patroclus and Menoetius, indicating whether the objects share a common origin and evolution, will explore the hypothesis that the system is a rare binary survivor of this scattering. (617) Patroclus is also a target of the upcoming Lucy mission, and constraints on surface composition would represent a valuable input to instrument configuration and observation planning work for the mission. As Lucy will not carry a UV instrument, the proposed observations would remain unique and complementary to the results of the mission.

Galactic planetary science

PubMed Central

Tinetti, Giovanna

2014-01-01

Planetary science beyond the boundaries of our Solar System is today in its infancy. Until a couple of decades ago, the detailed investigation of the planetary properties was restricted to objects orbiting inside the Kuiper Belt. Today, we cannot ignore that the number of known planets has increased by two orders of magnitude nor that these planets resemble anything but the objects present in our own Solar System. Whether this fact is the result of a selection bias induced by the kind of techniques used to discover new planets—mainly radial velocity and transit—or simply the proof that the Solar System is a rarity in the Milky Way, we do not know yet. What is clear, though, is that the Solar System has failed to be the paradigm not only in our Galaxy but even ‘just’ in the solar neighbourhood. This finding, although unsettling, forces us to reconsider our knowledge of planets under a different light and perhaps question a few of the theoretical pillars on which we base our current ‘understanding’. The next decade will be critical to advance in what we should perhaps call Galactic planetary science. In this paper, I review highlights and pitfalls of our current knowledge of this topic and elaborate on how this knowledge might arguably evolve in the next decade. More critically, I identify what should be the mandatory scientific and technical steps to be taken in this fascinating journey of remote exploration of planets in our Galaxy. PMID:24664916

Galactic planetary science.

PubMed

Tinetti, Giovanna

2014-04-28

Planetary science beyond the boundaries of our Solar System is today in its infancy. Until a couple of decades ago, the detailed investigation of the planetary properties was restricted to objects orbiting inside the Kuiper Belt. Today, we cannot ignore that the number of known planets has increased by two orders of magnitude nor that these planets resemble anything but the objects present in our own Solar System. Whether this fact is the result of a selection bias induced by the kind of techniques used to discover new planets--mainly radial velocity and transit--or simply the proof that the Solar System is a rarity in the Milky Way, we do not know yet. What is clear, though, is that the Solar System has failed to be the paradigm not only in our Galaxy but even 'just' in the solar neighbourhood. This finding, although unsettling, forces us to reconsider our knowledge of planets under a different light and perhaps question a few of the theoretical pillars on which we base our current 'understanding'. The next decade will be critical to advance in what we should perhaps call Galactic planetary science. In this paper, I review highlights and pitfalls of our current knowledge of this topic and elaborate on how this knowledge might arguably evolve in the next decade. More critically, I identify what should be the mandatory scientific and technical steps to be taken in this fascinating journey of remote exploration of planets in our Galaxy.

Tidal effects on Earth, Planets, Sun by far visiting moons

NASA Astrophysics Data System (ADS)

Fargion, Daniele

2016-07-01

The Earth has been formed by a huge mini-planet collision forming our Earth surface and our Moon today. Such a central collision hit was statistically rare. A much probable skimming or nearby encounter by other moons or planets had to occur. Indeed Recent observations suggest that many planetary-mass objects may be present in the outer solar system between the Kuiper belt and the Oort cloud. Gravitational perturbations may occasionally bring them into the inner solar system. Their passage near Earth could have generated gigantic tidal waves, large volcanic eruptions, sea regressions, large meteoritic impacts and drastic changes in global climate. They could have caused the major biological mass extinctions in the past in the geological records. For instance a ten times a terrestrial radius nearby impact scattering by a peripherical encounter by a small moon-like object will force huge tidal waves (hundred meter height), able to lead to huge tsunami and Earth-quake. Moreover the historical cumulative planet hits in larger and wider planets as Juppiter, Saturn, Uranus will leave a trace, as observed, in their tilted spin axis. Finally a large fraction of counter rotating moons in our solar system probe and test such a visiting mini-planet captur origination. In addition the Earth day duration variability in the early past did show a rare discountinuity, very probably indebt to such a visiting planet crossing event. These far planets in rare trajectory to our Sun may, in thousands event capture, also explain sudden historical and recent temperature changes.

Can Ecliptic Comets Be Created En Route from the Kuiper Belt?

NASA Astrophysics Data System (ADS)

Dones, Henry C. Luke; Womack, Maria; Nesvorny, David; Bierhaus, Edward B.; Zahnle, Kevin; Robbins, Stuart J.; Bottke, William; Alvarellos, Jose; Hamill, Patrick

2017-10-01

The Kuiper Belt is thought to be the reservoir of ecliptic comets (ECs), which include the Jupiter-family comets (JFCs) and Centaurs. ECs are also the main source of Sun-orbiting impactors on the regular moons of the giant planets (Zahnle et al. 2003). Ironically, we still do not know whether the belt, specifically its Scattered Disk, provides enough ECs (Volk and Malhotra 2008). We are investigating whether cometary breakup in the planetary region (Fernández 2009) can substantially increase the number of ECs. In support of this idea, the Kreutz sungrazers may derive from a hierarchical series of fragmentation events of a progenitor long-period comet (e.g., Sekanina and Chodas 2007), and the JFCs 42P and 53P appear to be fragments of a comet that split in 1845 (Kresák et al. 1984). On the other hand, although 16P was tidally disrupted by Jupiter in 1886, only one fragment survives.Models of the cometary orbital distribution ignore activity or apply a physical lifetime based on the number of passages within 2 or 3 AU of the Sun, where sublimation of water ice occurs (Nesvorný et al. 2017). In reality, some comets (e.g., 29P, Hale-Bopp) are active beyond Jupiter due to volatiles such as CO and CO2 (Womack et al. 2017). 174P/Echeclus underwent a 7-magnitude outburst at 13 AU (Rousselot et al. 2016), and CO emission was detected from Echeclus at 6 AU (Wierzchos et al. 2017). We will estimate how the number and size distribution of comet nuclei change with distance from the Sun due to cometary activity and spontaneous disruption, tidal disruption by a giant planet, and tidal disruption of binaries (Fraser et al. 2017).We thank the Cassini Data Analysis Program for support.Fernández Y (2009). Planet. Space. Sci. 57, 1218.Fraser WC, et al. (2017). Nat. Astron. 1, 0088.Kresák L, et al. (1984). IAU Circular 3940.Nesvorný D, et al. (2017). arXiv:1706.07447.Rousselot P, et al. (2016). MNRAS 462, S432.Sekanina, Z, Chodas, PW (2007). Astrophys. J. 663, 657.Volk K, Malhotra R (2008). Astrophys. J. 687, 714.Wierzchos K, Womack M, Sarid G. (2017). Astron. J. 153, id 230.Womack M, Sarid G, Wierzchos, K (2017). Publ. Astron. Soc. Pac. 129,031001.Zahnle K, et al. (2003). Icarus 163, 263.

Icy Satellites of Saturn: Impact Cratering and Age Determination

NASA Technical Reports Server (NTRS)

Dones, L.; Chapman, C. R.; McKinnon, William B.; Melosh, H. J.; Kirchoff, M. R.; Neukum, G.; Zahnle, K. J.

2009-01-01

Saturn is the first giant planet to be visited by an orbiting spacecraft that can transmit large amounts of data to Earth. Crater counts on satellites from Phoebe inward to the regular satellites and ring moons are providing unprecedented insights into the origin and time histories of the impacting populations. Many Voyager-era scientists concluded that the satellites had been struck by at least two populations of impactors. In this view, the Population I impactors, which were generally judged to be comets orbiting the Sun, formed most of the larger and older craters, while Population II impactors, interpreted as Saturn-orbiting ejecta from impacts on satellites, produced most of the smaller and younger craters. Voyager data also implied that all of the ring moons, and probably some of the midsized classical moons, had been catastrophically disrupted and reaccreted since they formed. We examine models of the primary impactor populations in the Saturn system. At the present time, ecliptic comets, which likely originate in the Kuiper belt/scattered disk, are predicted to dominate impacts on the regular satellites and ring moons, but the models require extrapolations in size (from the observed Kuiper belt objects to the much smaller bodies that produce the craters) or in distance (from the known active Jupiter family comets to 9.5 AU). Phoebe, Iapetus, and perhaps even moons closer to Saturn have been struck by irregular satellites as well. We describe the Nice model, which provides a plausible mechanism by which the entire Solar System might have experienced an era of heavy bombardment long after the planets formed. We then discuss the three cratering chronologies, including one based upon the Nice model, that have been used to infer surface ages from crater densities on the saturnian satellites. After reviewing scaling relations between the properties of impactors and the craters they produce, we provide model estimates of the present-day rate at which comets impact, and catastrophically disrupt, the saturnian moons. Finally, we present crater counts on the satellites from two different groups. Many of the heavily cratered terrains appear to be nearly saturated, so it is difficult to infer the provenance of the impactors from crater counts alone. More large craters have been found on Iapetus than on any other satellite. Enceladus displays an enormous range of surface ages, ranging from the old mid-latitude plains to the extremely young South Polar Terrain. Cassini images provide some evidence for the reality of Population II. Most of the observed craters may have formed in one or more cataclysms, but more work is needed to determine the roles of heliocentric and planetocentric bodies in creating the craters.

KSC-05pd2312

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, a technician from the Applied Physics Laboratory works on the New Horizons spacecraft before installing one of the panels. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2311

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory work on a panel they are installing on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2314

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory install another panel on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2315

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians from the Applied Physics Laboratory install another panel on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

KSC-05pd2313

NASA Image and Video Library

2005-10-07

KENNEDY SPACE CENTER, FLA. - At NASA Kennedy Space Center’s Payload Hazardous Servicing Facility, technicians work on a panel they are installing on the New Horizons spacecraft. A series of interconnecting panels will enclose the spacecraft beneath the antenna to maintain safe operating temperatures in space. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

WFIRST: Science in the Solar System

NASA Astrophysics Data System (ADS)

Milam, Stefanie N.; Holler, Bryan J.; Bauer, James M.; West, Robert; WFIRST Solar System Working Group

2018-01-01

Future space telescopes offer unprecedented sensitivity and spatial resolution at wavelengths that are inaccessible from the ground due to the Earth’s atmosphere, and will work in concert with future in situ robotic crafts and large ground-based facilities to address key questions for planetary science. Additionally, they provide broader perspectives in both targets and timelines for planetary missions that orbit, land, or fly by a given target. Space observatories are not constrained to a specific target, and provide global context as well as source-to-source comparisons that are not always achieved from directed missions.WFIRST will provide imaging and spectroscopic capabilities from 0.6-2.0 μm and will be a potential contemporary and eventual successor to JWST. Observations of asteroids, the giant planets and their satellites, Kuiper Belt Objects (KBOs), and comets will be possible through both the Guest Investigator (GI) and Guest Observer (GO) programs. Surveys of minor bodies and time domain studies of variable surfaces and atmospheres are uniquely well-suited for WFIRST with its 0.28 deg2 field of view (at ~0.11”/pixel). We will present our recent study of the capabilities for solar system science and highlight unique cases presented in the WFIRST white paper (arXiv: http://arxiv.org/abs/1709.02763).

KSC-05pd2323

NASA Image and Video Library

2005-10-11

KENNEDY SPACE CENTER, FLA. - Inside the mobile service tower on Launch Complex 41 at Cape Canaveral Air Force Station in Florida, workers oversee the lowering of the Lockheed Martin Atlas V Centaur stage (above) toward the first stage. The two stages will be mated. The Atlas V is the launch vehicle for the New Horizons spacecraft. New Horizons will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon's surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

Hands-On Universe: A Global Program for Education and Public Outreach in Astronomy

NASA Astrophysics Data System (ADS)

Boër, M.; Thiébaut, C.; Pack, H.; Pennypaker, C.; Isaac, M.; Melchior, A.-L.; Faye, S.; Ebisuzaki, T.

Hands-On Universe (HOU) is an educational program that enables students to investigate the Universe while applying tools and concepts from science, math, and technology. Using the Internet, HOU participants around the world request observations from an automated telescope, download images from a large image archive, and analyze them with the aid of user-friendly image processing software. This program is now in many countries, including the USA, France, Germany, Sweden, Japan, and Australia. A network of telescopes has been established, many of them remotely operated. Students in the classroom are able to make night observations during the day, using a telescope in another country. An archive of images taken on large telescopes is also accessible, as well as resources for teachers. Students deal with real research projects, e.g., the search for asteroids, which resulted in the discovery of a Kuiper Belt object by high-school students. Not only does Hands-On Universe give the general public access to professional astronomy, it also demonstrates the use of a complex automated system, data processing techniques, and automation. Using telescopes located in many countries over the globe, a powerful and genuine cooperation between teachers and children from various countries is promoted, with a clear educational goal.

Construction of a photometer to detect stellar occultations by outer solar system bodies for the Whipple mission concept

NASA Astrophysics Data System (ADS)

Kraft, Ralph P.; Kenter, Almus T.; Alcock, Charles; Murray, Stephen S.; Loose, Markus; Gauron, Thomas; Germain, Gregg; Peregrim, Lawrence

2014-08-01

The Whipple mission was a proposal submitted to the NASA Discovery AO in 2010 to study the solid bodies of the Kuiper Belt and Oort Cloud via a blind occultation survey. Though not accepted for flight, the proposal was awarded funding for technology development. Detecting a significant number of Trans Neptunian Objects (TNOs) via a blind occultation survey requires a low noise, wide field of view, multi object differential photometer. The light curve decrement is typically a few percent over timescales of tenths of seconds or seconds for Kuiper Belt and Oort cloud objects, respectively. To obtain a statistically interesting number of detections, this photometer needs to observe many thousands of stars over several years since the rate of occultation for a single star given the space density of the TNOs is low. The light curves from these stars must be monitored with a sensor with a temporal resolution of rv 25-50 ms and with a read noise of< 20 e- rms. Since these requirements are outside the capability of CCDs, the Whipple mission intends to use Teledyne H2RG HyViSI Silicon Hybrid CMOS detectors operating in "window" read mode. The full Whipple focal plane consists of a 3x3 array of these sensors, with each sensor comprised of 1024x 1024 36/μm pixels. Combined with the telescope optic, the Whipple focal plane provides a FOV of rv36 deg2 . In operation, each HyViSI detector, coupled to a Teledyne SIDECAR ASIC, monitors the flux from 650 stars at 40 Hz. The ASIC digitizes the data at the required cadence and an FPGA provides preliminary occultation event selection. The proposed 2010 Whipple mission utilized a spacecraft in a a "drift-away" orbit which signifi­ cantly limited the available telemetry data rate. Most of the light curve processing is required to be on-board the satellite so only candidate occultation events are telemetered to the ground. Occul­ tation light curves must be processed in real time on the satellite by an Field Programmable Gate Array (FPGA). A simple, real time band pass filter, called the Equivalent Width (EW) algorithm, has been instantiated in the FPGA. This EW filter selects for telemetry only those occultation event light curves that differed significantly from noise. As part of our technology development program, a key facet of the proposed Whipple focal plane was constructed and operated in our laboratory consisting of a single HyViSI H2RG sensor, a Teledyne SIDECAR ASIC, and a flight-like Virtex-5 FPGA. In order to fully demonstrate the capabilities of this photometer, we also made a occultation light-curve simulator. The entire system can generate simulated occultation light curves, project them onto an H2RG sensor, read out the sensor in windowing mode at 40 Hz, pass the data to an FPGA that continuously monitors the light curves and dumps candidate occultation events to our simulated Ground Support Equipment (GSE). In this paper, we summarize the technical capabilities of our system, present sample data, and discuss how this system will be used to support our proposal effort for the next Discovery round.

Probing for Exoplanets Hiding in Dusty Debris Disks: Disk Imaging, Characterization, and Exploration with HST-STIS Multi-roll Coronagraphy

NASA Technical Reports Server (NTRS)

Schneider, Glenn; Grady, Carol A.; Hines, Dean C.; Stark, Christopher C.; Debes, John; Carson, Joe; Kuchner, Marc J.; Perrin, Marshall; Weinberger, Alycia; Wisniewski, John P.;

Probing for exoplanets hiding in dusty debris disks: Disk imaging, characterization, and exploration with HST/STIS multi-roll coronagraphy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schneider, Glenn; Hinz, Phillip M.; Grady, Carol A.

Spatially resolved scattered-light images of circumstellar debris in exoplanetary systems constrain the physical properties and orbits of the dust particles in these systems. They also inform on co-orbiting (but unseen) planets, the systemic architectures, and forces perturbing the starlight-scattering circumstellar material. Using Hubble Space Telescope (HST)/Space Telescope Imaging Spectrograph (STIS) broadband optical coronagraphy, we have completed the observational phase of a program to study the spatial distribution of dust in a sample of 10 circumstellar debris systems and 1 'mature' protoplanetrary disk, all with HST pedigree, using point-spread-function-subtracted multi-roll coronagraphy. These observations probe stellocentric distances ≥5 AU for the nearestmore » systems, and simultaneously resolve disk substructures well beyond corresponding to the giant planet and Kuiper Belt regions within our own solar system. They also disclose diffuse very low-surface-brightness dust at larger stellocentric distances. Herein we present new results inclusive of fainter disks such as HD 92945 (F {sub disk}/F {sub star} = 5 × 10{sup –5}), confirming, and better revealing, the existence of a narrow inner debris ring within a larger diffuse dust disk. Other disks with ring-like substructures and significant asymmetries and complex morphologies include HD 181327, for which we posit a spray of ejecta from a recent massive collision in an exo-Kuiper Belt; HD 61005, suggested to be interacting with the local interstellar medium; and HD 15115 and HD 32297, also discussed in the context of putative environmental interactions. These disks and HD 15745 suggest that debris system evolution cannot be treated in isolation. For AU Mic's edge-on disk, we find out-of-plane surface brightness asymmetries at ≥5 AU that may implicate the existence of one or more planetary perturbers. Time-resolved images of the MP Mus protoplanetary disk provide spatially resolved temporal variability in the disk illumination. These and other new images from our HST/STIS GO/12228 program enable direct inter-comparison of the architectures of these exoplanetary debris systems in the context of our own solar system.« less

To Boldly Go: America's Next Era in Space. Probing the Primordial Constituents of Our Solar System

NASA Technical Reports Server (NTRS)

1995-01-01

Dr. France Cordova, NASA's Chief Scientist, chaired this, another seminar in the Administrator's Seminar Series. She introduced NASA Administrator, Daniel S. Goldin, who greeted the attendees, and noted that, from the day people first looked into the sky, they've wondered what was up there, who or what created it, is Earth unique, what shaped the solar system, what is the Kuiper Belt and why is it there, and what are the solar system's building blocks. NASA's missions may discover some of the answers. Dr. Cordova then introduced Dr. Anita Cochran, research scientist at the University of Texas. Dr. Cochran has been searching for some of this information. She is especially interested in finding out when various planets and asteroids were discovered, what their orbits are, when the solar system was formed, and more about the comets in the Kuiper Belt. Are they icy planetisimals that helped form our solar system? Dr. Toby Owen of the University of Hawaii faculty spoke next. He believes that life on Earth exists because comets brought water and a variety of light elements to Earth from the outer parts of the solar system. Without them, we couldn't exist. He noted that noble gases don't mix with other gases. Gases come to Earth via rocks and by bombardment. Ice can trap argon and carbon, but not neon. Dr. Owens concluded with comments that we need 'better numbers for the Martian atmosphere', and it would be good to get samples of material from a comet. The third speaker was Dr. Eugene Shoemaker of the Lowell Observatory and the U.S. Geological Survey. He is credited with discovering more than 800 asteroids and learning about the Oort Cloud, which is believed to be a cloud of rocks and dust that may surround our solar system and be where comets originate. Comet storms reoccur about every 30 million years. Dr. Shoemaker suggested that since we are presently in a period of comet showers, it would be good to get a comet sample. It might provide insight regarding the origin of life. Additional information is included in the original extended abstract.

Proceedings of the 38th Lunar and Planetary Science Conference

NASA Technical Reports Server (NTRS)

2007-01-01

The sessions in the conference include: Titan, Mars Volcanism, Mars Polar Layered Deposits, Early Solar System Isotopes, SPECIAL SESSION: Mars Reconnaissance Orbiter: New Ways of Studying the Red Planet, Achondrites: Exploring Oxygen Isotopes and Parent-Body Processes, Solar System Formation and Evolution, SPECIAL SESSION: SMART-1, . Impact Cratering: Observations and Experiments, SPECIAL SESSION: Volcanism and Tectonism on Saturnian Satellites, Solar Nebula Composition, Mars Fluvial Geomorphology, Asteroid Observations: Spectra, Mostly, Mars Sediments and Geochemistry: View from the Surface, Mars Tectonics and Crustal Dichotomy, Stardust: Wild-2 Revealed, Impact Cratering from Observations and Interpretations, Mars Sediments and Geochemistry: The Map View, Chondrules and Their Formation, Enceladus, Asteroids and Deep Impact: Structure, Dynamics, and Experiments, Mars Surface Process and Evolution, Martian Meteorites: Nakhlites, Experiments, and the Great Shergottite Age Debate, Stardust: Mainly Mineralogy, Astrobiology, Wind-Surface Interactions on Mars and Earth, Icy Satellite Surfaces, Venus, Lunar Remote Sensing, Space Weathering, and Impact Effects, Interplanetary Dust/Genesis, Mars Cratering: Counts and Catastrophes?, Chondrites: Secondary Processes, Mars Sediments and Geochemistry: Atmosphere, Soils, Brines, and Minerals, Lunar Interior and Differentiation, Mars Magnetics and Atmosphere: Core to Ionosphere, Metal-rich Chondrites, Organics in Chondrites, Lunar Impacts and Meteorites, Presolar/Solar Grains, Topics for Print Only papers are: Outer Planets/Satellites, Early Solar System, Interplanetary Dust, Comets and Kuiper Belt Objects, Asteroids and Meteoroids, Chondrites, Achondrites, Meteorite Related, Mars Reconnaissance Orbiter, Mars, Astrobiology, Planetary Differentiation, Impacts, Mercury, Lunar Samples and Modeling, Venus, Missions and Instruments, Global Warming, Education and Public Outreach, Poster sessions are: Asteroids/Kuiper Belt Objects, Galilean Satellites: Geology and Mapping, Titan, Volcanism and Tectonism on Saturnian Satellites, Early Solar System, Achondrite Hodgepodge, Ordinary Chondrites, Carbonaceous Chondrites, Impact Cratering from Observations and Interpretations, Impact Cratering from Experiments and Modeling, SMART-1, Planetary Differentiation, Mars Geology, Mars Volcanism, Mars Tectonics, Mars: Polar, Glacial, and Near-Surface Ice, Mars Valley Networks, Mars Gullies, Mars Outflow Channels, Mars Sediments and Geochemistry: Spirit and Opportunity, Mars Reconnaissance Orbiter: New Ways of Studying the Red Planet, Mars Reconnaissance Orbiter: Geology, Layers, and Landforms, Oh, My!, Mars Reconnaissance Orbiter: Viewing Mars Through Multicolored Glasses; Mars Science Laboratory, Phoenix, and ExoMars: Science, Instruments, and Landing Sites; Planetary Analogs: Chemical and Mineral, Planetary Analogs: Physical, Planetary Analogs: Operations, Future Mission Concepts, Planetary Data, Imaging, and Cartography, Outer Solar System, Presolar/Solar Grains, Stardust Mission; Interplanetary Dust, Genesis, Asteroids and Comets: Models, Dynamics, and Experiments, Venus, Mercury, Laboratory Instruments, Methods, and Techniques to Support Planetary Exploration; Instruments, Techniques, and Enabling Techologies for Planetary Exploration; Lunar Missions and Instruments, Living and Working on the Moon, Meteoroid Impacts on the Moon, Lunar Remote Sensing, Lunar Samples and Experiments, Lunar Atmosphere, Moon: Soils, Poles, and Volatiles, Lunar Topography and Geophysics, Lunar Meteorites, Chondrites: Secondary Processes, Chondrites, Martian Meteorites, Mars Cratering, Mars Surface Processes and Evolution, Mars Sediments and Geochemistry: Regolith, Spectroscopy, and Imaging, Mars Sediments and Geochemistry: Analogs and Mineralogy, Mars: Magnetics and Atmosphere, Mars Aeolian Geomorphology, Mars Data Processing and Analyses, Astrobiology, Engaging Student Educators and the Public in Planetary Science,

Gerard Kuiper and the Infrared Detector

NASA Astrophysics Data System (ADS)

Sears, Derek

2013-10-01

The life and contributions of Gerard Kuiper have been documented by Dale Cruikshank in his National Academy of Sciences biography. I will argue that particularly important in this eventful life was Kuiper's war time experiences. Kuiper's wartime role evolved as the war unfolded, but towards the end he was charged by the US military with reporting German progress with war-related technologies and the activities of scientists under Nazi control. He interviewed a great many scientists, including his own PhD mentor (Ejnar Hertzsprung), and when Kuiper was the only person available, he interviewed concentration-camp victims. He carried briefing sheets that identified the technologies being sought by the allies and the major fraction of these involved infrared equipment. He sent back to the USA boxes of documents, and large amounts of equipment, and he stressed to the military his interest in these for his own research. It seems very likely that in this way an effective PbS infrared detector, so critical to Kuiper's career and the future of planetary science, came to the USA and to Robert Cashman's laboratory at Northwestern University. As the war was winding down, Cashman and Kuiper worked together to develop a practical infrared spectrometer for astronomical use. Within months, Kuiper discovered the C02 atmospheres on Mars and Venus.

Tying Extinction Events to Comet Impacts Large Enough to Cause an Extinction in Themselves.

NASA Astrophysics Data System (ADS)

Burgener, J. A.

2017-12-01

Comets over 35 km in size impacting Earth will create vast fireballs, and will boil large parts of the oceans, causing extinction events in themselves. They will likely provide enough energy to shatter the crust and eject large masses of molten rock from the mantle, forming traps. Traps are clearly associated with extinction events, but are not expected to cause extinctions. While Chicxulub is recognized to have occurred at the time of the K/Pg boundary layer, it is recognized as being too small in itself to cause an extinction. Are large comet impacts likely? The Kuiper belt has more than 100,000 objects over 100 km in diameter and millions over 10 km. Typically their orbits are less stable than asteroid orbits due to large bodies such as Pluto moving through the belt. The asteroid belt has only 10,000 objects over 10 km diameter. Comet impacts should be more common than asteroid impacts, yet none of the recognized craters are expected to be due to comets. There are many features on Earth that are poorly explained by Plate Tectonics that would be well explained if they were considered to be comet impact craters. A consideration of the Black Sea and the Tarim Basin will show that impact interpretations are a better fit than the present Plate Tectonics' explanations. Both basins are in the midst of mountain building from plate collisions, but are themselves not being disturbed by the plate collisions. Both are ellipses angled at 23.4 degrees to the equator, matching the angle expected for a low angle impact from a comet traveling in the ecliptic. Both are too deep at 15 km depths to be standard oceans (typically 5 km deep). Both are filled with horizontal layers of sediments, undisturbed by the mountain building occurring at the edges. Both have thin crusts and high Moho boundaries. Both have thin lithosphere. Yet both show GPS movement of the land around them moving away from them, as though they were much thicker and stronger than the surrounding land. The Tarim Basin is 1000 km X 380 km, and the Black Sea is in two sections each 600 km X 350 km. They would require impactors in the range of 35 - 40 km diameter, hitting at impact angles of 20 - 30 degrees. The fireballs from such impacts would cover nearly half the planet, which would be large enough in themselves to cause extinctions.

Numerical simulations of impacts involving porous bodies. II. Comparison with laboratory experiments

NASA Astrophysics Data System (ADS)

Jutzi, Martin; Michel, Patrick; Hiraoka, Kensuke; Nakamura, Akiko M.; Benz, Willy

2009-06-01

In this paper, we compare the outcome of high-velocity impact experiments on porous targets, composed of pumice, with the results of simulations by a 3D SPH hydrocode in which a porosity model has been implemented. The different populations of small bodies of our Solar System are believed to be composed, at least partially, of objects with a high degree of porosity. To describe the fragmentation of such porous objects, a different model is needed than that used for non-porous bodies. In the case of porous bodies, the impact process is not only driven by the presence of cracks which propagate when a stress threshold is reached, it is also influenced by the crushing of pores and compaction. Such processes can greatly affect the whole body's response to an impact. Therefore, another physical model is necessary to improve our understanding of the collisional process involving porous bodies. Such a model has been developed recently and introduced successfully in a 3D SPH hydrocode [Jutzi, M., Benz, W., Michel, P., 2008. Icarus 198, 242-255]. Basic tests have been performed which already showed that it is implemented in a consistent way and that theoretical solutions are well reproduced. However, its full validation requires that it is also capable of reproducing the results of real laboratory impact experiments. Here we present simulations of laboratory experiments on pumice targets for which several of the main material properties have been measured. We show that using the measured material properties and keeping the remaining free parameters fixed, our numerical model is able to reproduce the outcome of these experiments carried out under different impact conditions. This first complete validation of our model, which will be tested for other porous materials in the future, allows us to start addressing problems at larger scale related to small bodies of our Solar System, such as collisions in the Kuiper Belt or the formation of a family by the disruption of a porous parent body in the main asteroid belt.

Near-Infrared photometry of BOs and Centaurs in support of Spitzer Space Telescope data

NASA Astrophysics Data System (ADS)

Pinilla-Alonso, Noemi; Emery, Josh P.; Trilling, David; Mommert, Michael

2014-08-01

We propose to measure near-infrared broadband colors of Centaurs and Kuiper Belt objects (KBOs). The proposed ground-based observations will complement 3.6 and 4.5 microns photometry of these bodies obtained with the Infrared Array Camera (IRAC) on the Spitzer Space Telescope. Extending reflectances past 2.5 micron with Spitzer enables sensitive searches for absorptions in the 3 to 5 micron region, where relevant species (e.g., complex organics, H2O, CO2, CH4, hydrated silicates) have their fundamental absorption bands. In order to assess the presence of absorptions, however, the Spitzer photometry must be tied to shorter wavelength near-infrared reflectances. Recently, Wright et al. (2012) combined IRAC/Spitzer and NIR colors for a sample of cold KBOs and showed how powerful this technique is detecting the presence of volatiles. In semester 2011B we obtained Gemini NIR data for 12 KBOs (results were presented in the DPS Meeting 2012 and part is included in the Master Dissertation of D. Wright, under the supervision of J.P. Emery). In semester 2011B and 2013A we obtained Gemini NIR data for 12 and 7 KBOs respectively (part of these results were presented in the DPS Meeting 2012 and part is included in the Master Dissertation of D. Wright, under the supervision of J.P. Emery). But our sample is not yet completed and we need more time to complete our study and cover a larger number of targets from our sample of Spitzer data. Approximately 54 objects in our sample that lack NIR colors are visible from GEMINI South in 2014B semester, we propose here to observe 16 of these objects.

THE HUBBLE WIDE FIELD CAMERA 3 TEST OF SURFACES IN THE OUTER SOLAR SYSTEM: SPECTRAL VARIATION ON KUIPER BELT OBJECTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fraser, Wesley C.; Brown, Michael E.; Glass, Florian, E-mail: wesley.fraser@nrc.ca

2015-05-01

Here, we present additional photometry of targets observed as part of the Hubble Wide Field Camera 3 (WFC3) Test of Surfaces in the Outer Solar System. Twelve targets were re-observed with the WFC3 in the optical and NIR wavebands designed to complement those used during the first visit. Additionally, all of the observations originally presented by Fraser and Brown were reanalyzed through the same updated photometry pipeline. A re-analysis of the optical and NIR color distribution reveals a bifurcated optical color distribution and only two identifiable spectral classes, each of which occupies a broad range of colors and has correlatedmore » optical and NIR colors, in agreement with our previous findings. We report the detection of significant spectral variations on five targets which cannot be attributed to photometry errors, cosmic rays, point-spread function or sensitivity variations, or other image artifacts capable of explaining the magnitude of the variation. The spectrally variable objects are found to have a broad range of dynamical classes and absolute magnitudes, exhibit a broad range of apparent magnitude variations, and are found in both compositional classes. The spectrally variable objects with sufficiently accurate colors for spectral classification maintain their membership, belonging to the same class at both epochs. 2005 TV189 exhibits a sufficiently broad difference in color at the two epochs that span the full range of colors of the neutral class. This strongly argues that the neutral class is one single class with a broad range of colors, rather than the combination of multiple overlapping classes.« less

The evolution of a Pluto-like system during the migration of the ice giants

NASA Astrophysics Data System (ADS)

Pires, Pryscilla; Giuliatti Winter, Silvia M.; Gomes, Rodney S.

2015-01-01

The planetary migration of the Solar System giant planets in the framework of the Nice model (Tsiganis, K., Gomes, R., Morbidelli, A., Levison, H.F. [2005]. Nature 435,459-461; Morbidelli, A., Levison, H.F., Tsiganis, K., Gomes, R. [2005]. Nature 435, 462-465; Gomes, R., Levison, H.F., Tsiganis, K., Morbidelli, A. [2005]. Nature 435, 466-469) creates a dynamical mechanism which can be used to explain the distribution of objects currently observed in the Kuiper belt (e.g., Levison, H.F., Morbidelli, A., Vanlaerhoven, C., Gomes, R., Tsiganis, K. [2008]. Icarus 196, 258-273). Through this mechanism the planetesimals within the disk, heliocentric distance ranging from beyond Neptune's orbit to approximately 34 AU, are delivered to the belt after a temporary eccentric phase of Uranus and Neptune's orbits. We reproduced the mechanism proposed by Levison et al. to implant bodies into the Kuiper belt. The capture of Pluto into the external 3:2 mean motion resonance with Neptune is associated with this gravitational scattering model. We verified the existence of several close encounters between the ice giants and the planetesimals during their outward radial migration, then we believe that the analysis of the dynamical history of the plutonian satellites during this kind of migration is important, and would provide some constrains about their place of formation - within the primordial planetesimal disk or in situ. We performed N-body simulations and recorded the trajectories of the planetesimals during close approaches with Uranus and Neptune. Close encounters with Neptune are the most common, reaching approximately 1200 in total. A Pluto similarly sized body assumed the hyperbolic trajectories of the former primordial planetesimal with respect to those giant planets. We assumed the current mutual orbital configuration and sizes for Pluto's satellites, then we found that the rate of destruction of systems similar to that of Pluto with closest approaches to Uranus or Neptune <0.10 AU is 40%, i.e. these close approaches can lead to ejections of satellites or to changes in the satellites eccentricities at least 1 order of magnitude larger than the currently observed. However, we also found that the number of closest approaches which the minimum separation to Uranus or Neptune <0.10 AU is negligible, reaching 6%. In the other 60% of close encounter histories with closest approaches >0.10 AU, none of the systems have been destroyed. The latter sample concentrates 94% of closest approaches with the ice giants. Recall that throughout the early history of the Solar System giant impacts were common (McKinnon, W.B. [1989]. Astrophys. J. 344, L41-L44; Stern, A. [1991]. Icarus 90; Canup, R.M. [2005]. Science 307, 546-550). Also, impacts capable of forming a binary like Pluto-Charon can occur possibly prior to 0.5-1 Gyr (Kenyon, S.J., Bromley, B.C. [2014]. Astron. J. 147, 8), and small satellites such as Nix and Hydra can grow in debris from the giant impact (e.g., Canup, R.M. [2011]. Astron. J. 141, 35). Thus, we conclude that if Pluto and its satellites were emplaced into the KB from lower heliocentric orbits, then the Pluto system could survive the encounters that may have happened for emplacement of the Plutinos through the mechanism proposed by Levison et al.

Preparing for LSST with the LCOGT NEO Follow-up Network

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Lister, Tim; Gomez, Edward

2016-10-01

The Las Cumbres Observatory Global Telescope Network (LCOGT) provides an ideal platform for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects (NEOs)) and ultimately for the discovery of new objects. The LCOGT NEO Follow-up Network is using the LCOGT telescope network in addition to a web-based system developed to perform prioritized target selection, scheduling, and data reduction to confirm NEO candidates and characterize radar-targeted known NEOs.In order to determine how to maximize our NEO follow-up efforts, we must first define our goals for the LCOGT NEO Follow-up Network. This means answering the following questions. Should we follow-up all objects brighter than some magnitude limit? Should we only focus on the brightest objects or push to the limits of our capabilities by observing the faintest objects we think we can see and risk not finding the objects in our data? Do we (and how do we) prioritize objects somewhere in the middle of our observable magnitude range? If we want to push to faint objects, how do we minimize the amount of data in which the signal-to-noise ratio is too low to see the object? And how do we find a balance between performing follow-up and characterization observations?To help answer these questions, we have developed a LCOGT NEO Follow-up Network simulator that allows us to test our prioritization algorithms for target selection, confirm signal-to-noise predictions, and determine ideal block lengths and exposure times for observing NEO candidates. We will present our results from the simulator and progress on our NEO follow-up efforts.In the era of LSST, developing/utilizing infrastructure, such as the LCOGT NEO Follow-up Network and our web-based platform for selecting, scheduling, and reducing NEO observations, capable of handling the large number of detections expected to be produced on a daily basis by LSST will be critical to follow-up efforts. We hope our work can act as an example and tool for the community as together we prepare for the age of LSST.

An historic discovery around the corner from school: Ceres, a solar system object with an uncertain identity.

NASA Astrophysics Data System (ADS)

Stira, Salvatore

2016-04-01

Ceres is the largest object in the asteroid belt between Mars and Jupiter, and it was discovered on January 1, 1801, by the Italian astronomer Giuseppe Piazzi. The study of Ceres is especially relevant to my students because this celestial body was discovered in Palermo, in the astronomic observatory located in the UNESCO world heritage site "Palazzo dei Normanni", around 500 meters away from the institute where I teach, and because Ceres was considered the patron goddess of Sicily. Moreover, it received scientists and media attention recently because it was explored by the NASA Dawn spacecraft in 2015. The categorization of Ceres has changed more than once and has been the subject of some disagreement. It was originally considered a planet, but was reclassified as an asteroid in the 1850s when many other objects in similar orbits were discovered. Its status changed again in 2006 when it was promoted to dwarf planet, a classification it shares with Pluto and other Kuiper belt objects. The study of this celestial body has a notable educational value, since the uncertain identity of Ceres constitutes an occasion to reflect on the criterions of classification of the natural objects. The history of its discovery allows the students to understand as the scientific method doesn't always consist in the verification of hypothesis through experiments but it sometimes asks for the forecast of facts through mathematical calculations, repeated and methodic observations, the collaboration between scientists of different sectors and nationality. Furthermore, it is a particularly suitable topic for interdisciplinary connections, as regards both scientific and humanistic matters. In order to promote the scientific competences of my first class students, I have developed a learning unit on Ceres, thanks to good cooperation with the Palermo Observatory scientists, particularly active in the astronomic dissemination towards the schools and the citizens. The most meaningful activities of the learning units have been: 1) Working in groups: classification of solar system objects through the use of cards with figures and description of the celestial bodies. 2) A guided tour to Palermo Astronomic Observatory Museum, where stored instruments used by Piazzi for observation of Ceres and the original scientific documentation regarding this important discovery. 3) Internet search of information on the mission Dawn and implementation of Learning objects on this matter. 4) A guided visit to the exhibition "Cerere, da Piazzi a Dawn"; This learning unit, that has aroused interest and active participation among the students, cannot be regarded as closed, because it can be used for the discussion of other matters (for instance the search of the life on other celestial bodies).

Kuipers trims his hair in the Node 3

NASA Image and Video Library

2011-12-30

ISS030-E-033523 (30 Dec. 2011) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, trims his hair in the Tranquility node of the International Space Station. Kuipers used hair clippers fashioned with a vacuum device to garner freshly cut hair.

Kuipers trims his hair in the Node 3

NASA Image and Video Library

2011-12-30

ISS030-E-033548 (30 Dec. 2011) --- European Space Agency astronaut Andre Kuipers, Expedition 30 flight engineer, trims his hair in the Tranquility node of the International Space Station. Kuipers used hair clippers fashioned with a vacuum device to garner freshly cut hair.

The colors of cometary nuclei and other primitive bodies

NASA Astrophysics Data System (ADS)

Toth, I.; Lamy, P. L.

2005-12-01

Primitive minor objects like Kuiper-belt objects (KBOs), Centaurs, cometary nuclei and low-albedo asteroids contain a considerable amount of information regarding the formation of early solar system planetesimals and some of the primordial processes. Broadband colors by themselves offer limited insight into surface composition but correlations either between different color indices or with other (e.g., orbital) parameters can shed some light on the questions of the composition and the evolution of the minor objects. Furthermore, a systematic comparison of the color indices of various populations may provide clues on their relationships, and concur along with dynamical studies, to establish a scenario of their formation and evolution in the solar system. We present new color results on cometary nuclei obtained with the Hubble Space Telescope (HST) whose superior resolution enables us to accurately isolate the nucleus signals from the surrounding comae. By combining with scrutinized available data obtained with ground-based telescopes, we accumulated a sample of 39 cometary nuclei, 34 ecliptic comets (ECs) and 5 nearly-isotropic comets (NICs) using the nomenclature of Levison (1996). We analyze color distributions and color-color correlations as well as correlations with other physical parameters. We present our own compilation of colors of 282 objects in the outer solar system, separately considering the different dynamical populations, classical KBOs in low and high-inclination orbits, resonant KBOs (practically Plutinos), scattered-disk objects (SDOs) and Centaurs. We perform a systematic analysis of color distributions of all plausible parent-child combinations and conclude by synthesizing the implications of the colors for the origin of ecliptic comets. We acknowledge the support of the French "Programme National de Planétologie", jointly funded by CNRS and CNES, and of the bilateral French--Hungarian cooperation program. I. Toth further acknowledges the support of the Université de Provence, of the Hungarian Academy of Sciences through grant No. 9871.

RADIOLYSIS OF NITROGEN AND WATER-ICE MIXTURE BY FAST IONS: IMPLICATIONS FOR KUIPER BELT OBJECTS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barros, A. L. F. de; Silveira, E. F da; Bergantini, A.

The participation of condensed nitrogen in the surface chemistry of some objects in the outer solar system, such as Pluto and Triton, is very important. The remote observation of this species using absorption spectroscopy is a difficult task because N{sub 2} is not IR active in the gas phase. Water is also among the most abundant molecules in the surface of these objects; chemical reactions between N{sub 2} and H{sub 2}O induced by cosmic rays are therefore expected. Although pure N{sub 2} ice is hardly identified by IR spectroscopy, the species produced through the processing of the surface ice bymore » cosmic rays may give relevant clues indicating how abundant the N{sub 2} is in the outside layers of the surface of trans-Neptunian objects (TNOs). The objective of this work is to investigate the formation of nitrogenated species induced by cosmic-ray analogs in an ice mixture containing nitrogen and water. Experiments were performed in the GANIL Laboratory by bombarding N{sub 2}:H{sub 2}O (10:1) ice at 15 K with 40 MeV {sup 58}Ni{sup 11+} ions. Evolution of precursor and daughter species was monitored by Fourier transform infrared spectrometry. The main produced species are the nitrogen oxides NO{sub k} (k = 1–3), N{sub 2}O{sub j} (j = 1–5), N{sub 3}, and O{sub 3}. Among them, the N{sub 2}O and N{sub 3} are the most abundant, representing ∼61% of the total column density of the daughter molecules at 10{sup 13} ions cm{sup −2} fluence; the current results indicate that the yield of daughter species from this mixture is low, and this may be one of the reasons why N{sub i}O{sub j} molecules are not usually observed in TNOs.« less

Ice Giant Exploration

NASA Astrophysics Data System (ADS)

Rymer, A. M.; Arridge, C. S.; Masters, A.; Turtle, E. P.; Simon, A. A.; Hofstadter, M. D.; Turrini, D.; Politi, R.

2015-12-01

The Ice Giants in our solar system, Uranus and Neptune, are fundamentally different from their Gas Giant siblings Jupiter and Saturn, from the different proportions of rock and ice to the configuration of their planetary magnetic fields. Kepler space telescope discoveries of exo-planets indicate that planets of this type are among the most ubiquitous universally and therefore a future mission to explore the nature of the Ice Giants in our own solar system will provide insights into the nature of extra-solar system objects in general. Uranus has the smallest self- luminosity of all the planets, potentially related to catastrophic events early in the planet's history, which also may explain Uranus' large obliquity. Uranus' atmosphere is subject to extreme seasonal forcing making it unique in the Solar System. Neptune is also unique in a number of ways, notably its large moon Triton which is likely a captured Kuiper Belt Object and one of only two moons in the solar system with a robustly collisional atmosphere. Similar to Uranus, the angle between the solar wind and the magnetic dipole axis is subject to large-amplitude variations on both diurnal and seasonal timescales, but peculiarly it has one of the quietest magnetospheres of the solar system, at least according to Voyager 2, the only spacecraft to encounter Neptune to date. A comprehensive mission, as advocated in the Decadal Survey, would provide enormous science return but is also challenging and expensive. In this presentation we will discuss mission scenarios and suggest how collaboration between disciplines and internationally can help us to pursue a mission that includes Ice Giant exploration.

Near-infrared colors of minor planets recovered from VISTA-VHS survey (MOVIS)

NASA Astrophysics Data System (ADS)

Popescu, M.; Licandro, J.; Morate, D.; de León, J.; Nedelcu, D. A.; Rebolo, R.; McMahon, R. G.; Gonzalez-Solares, E.; Irwin, M.

2016-06-01

Context. The Sloan Digital Sky Survey (SDSS) and Wide-field Infrared Survey Explorer (WISE) provide information about the surface composition of about 100 000 minor planets. The resulting visible colors and albedos enabled us to group them in several major classes, which are a simplified view of the diversity shown by the few existing spectra. A large set of data in the 0.8-2.5 μm, where wide spectral features are expected, is required to refine and complement the global picture of these small bodies of the solar system. Aims: We aim to obtain the near-infrared colors for a large sample of solar system objects using the observations made during the VISTA-VHS survey. Methods: We performed a serendipitous search in VISTA-VHS observations using a pipeline developed to retrieve and process the data that corresponds to solar system objects (SSo). The resulting photometric data is analyzed using color-color plots and by comparison with the known spectral properties of asteroids. Results: The colors and the magnitudes of the minor planets observed by the VISTA survey are compiled into three catalogs that are available online: the detections catalog (MOVIS-D), the magnitudes catalog (MOVIS-M), and the colors catalog (MOVIS-C). They were built using the third data release of the survey (VISTA VHS-DR3). A total of 39 947 objects were detected, including 52 NEAs, 325 Mars Crossers, 515 Hungaria asteroids, 38 428 main-belt asteroids, 146 Cybele asteroids, 147 Hilda asteroids, 270 Trojans, 13 comets, 12 Kuiper Belt objects and Neptune with its four satellites. The colors found for asteroids with known spectral properties reveal well-defined patterns corresponding to different mineralogies. The distributions of MOVIS-C data in color-color plots shows clusters identified with different taxonomic types. All the diagrams that use (Y - J) color separate the spectral classes more effectively than the (J - H) and (H - Ks) plots used until now: even for large color errors (<0.1), the plots (Y - J) vs. (Y - Ks) and (Y - J) vs. (J - Ks) provide the separation between S-complex and C-complex. The end members A, D, R, and V-types occupy well-defined regions. The catalogs are only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (http://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/591/A115

Zodiac II: Debris Disk Science from a Balloon

NASA Technical Reports Server (NTRS)

Bryden, Geoffrey; Traub, Wesley; Roberts, Lewis C., Jr.; Bruno, Robin; Unwin, Stephen; Backovsky, Stan; Brugarolas, Paul; Chakrabarti, Supriya; Chen, Pin; Hillenbrand, Lynne;

Zodiac II: Debris Disk Science from a Balloon

NASA Technical Reports Server (NTRS)

Bryden, Geoffrey; Traub, Wesley; Roberts, Lewis C., Jr.; Bruno, Robin; Unwin, Stephen; Backovsky, Stan; Brugarolas, Paul; Chakrabarti, Supriya; Chen, Pin; Hillenbrand, Lynne;

How Dusty Is Alpha Centauri? Excess or Non-excess over the Infrared Photospheres of Main-sequence Stars

NASA Technical Reports Server (NTRS)

Wiegert, J.; Liseau, R.; Thebault, P.; Olofsson, G.; Mora, A.; Bryden, G.; Marshall, J. P.; Eiroa, C.; Montesinos, B.; Ardila, D.;

Triton: The Connection between Rosetta, New Horizons and a future Ice Giants Mission

NASA Astrophysics Data System (ADS)

Mandt, K.; Luspay-Kuti, A.; Mousis, O.

2017-12-01

Several planetary missions have made observations intended to evaluate the origin and evolution of volatiles in solar system atmospheres. This is an important topic that connects how planets, moons and small bodies formed to the question of past or present habitability. Comet isotope observations have been ongoing and have played a crucial role in this research. Measurements of the D/H in cometary water and 14N/15N in NH3, in particular, have been critical for evaluating the origin of water and nitrogen in the terrestrial planet atmospheres and for that of Saturn's moon Titan. We have conducted comparative studies modeling the escape, photochemistry and evolution of the atmospheres of Titan and Pluto to try to understand whether the nitrogen in these atmospheres originated as N2 or NH3 in the protosolar nebula. The origin of Titan's nitrogen has been well constrained, but uncertainties about isotope processes in Pluto's atmosphere leave the origin of Pluto's nitrogen difficult to resolve. Because of their similarities, Triton is subject to the same uncertainties and is of particular interest for understanding the origin of Triton's and Pluto's volatiles as well as of Kuiper Belt Objects in general. We will discuss how Rosetta, New Horizons and a future Ice Giants mission will each contribute to understanding the origin of nitrogen in these atmospheres and to the origin of volatiles in atmospheres throughout outer solar system.

Energetic Particles in the far and near Environment of Pluto

NASA Astrophysics Data System (ADS)

Kollmann, P.; Hill, M. E.; McNutt, R. L., Jr.; Brown, L. E.; Kusterer, M. B.; Vandegriff, J. D.; Smith, H. T.; Mitchell, D. G.; Haggerty, D. K.; Bagenal, F.; Krimigis, S. M.; Lisse, C. M.; Delamere, P. A.; Elliott, H. A.; Horanyi, M.; McComas, D. J.; Piquette, M. R.; Poppe, A. R.; Sidrow, E. J.; Strobel, D. F.; Szalay, J.; Valek, P. W.; Weidner, S.; Zirnstein, E.; Ennico Smith, K.; Olkin, C.; Weaver, H. A., Jr.; Young, L. A.; Stern, A.

2015-12-01

The New Horizons spacecraft was launched in 2006, passed Jupiter and its magnetotail, took continuous measurements in the solar wind throughout the recent years, and flew by Pluto in July 2015. The onboard PEPSSI instrument measures ion and electron intensities, masses, and energies in the keV to MeV range. The closest approach distance to Pluto was 11 Pluto radii, inside the orbit of Charon. Data taken near Pluto is downlinked throughout August. We will present analysis of this data and set it into context with previous measurements. We expect a number of interesting particle structures around Pluto. Parts of Pluto's molecular nitrogen atmosphere is escaping and will co-orbit with Pluto, potentially forming a partial gas torus. This torus can be additionally sourced by other Kuiper belt objects. The neutrals are eventually ionized and pick-up by the solar wind brings them into the PEPSSI energy range. The measured ion densities can be used to constrain the Pluto torus. Pluto is not expected to have an intrinsic magnetic field, but the energetic particle data can be used to infer its properties, if any. Pluto interacts instead with the solar wind via the pick-up of its ions and the magnetic fields created by currents in its ionosphere. The relative role of these mechanisms can be revealed by the flyby data and directly compared to data that was taken at Jupiter with identical instrumentation.

The Science and Prospects of Astrophysical Observations with New Horizons

NASA Astrophysics Data System (ADS)

Nguyen, Chi; Zemcov, Michael; Cooray, Asantha; Lisse, Carey; Poppe, Andrew

2018-01-01

Astrophysical observation from the outer solar system provides a unique and quiet vantage point from which to understand our cosmos. If properly designed, such observations enable several niche science cases that are difficult or impossible to perform near Earth. NASA's New Horizons mission includes several instruments with ~10cm telescopes that provide imaging capability from UV to near-IR wavelengths with moderate spectral resolution. A carefully designed survey can optimize the expendable propellant and limited data telemetry bandwidth to allow several unique measurements, including a detailed understanding of the cosmic extragalactic background light in the optical and near-IR, studies of the local and extragalactic UV background, measurements of the properties of dust and ice in the outer solar system, searches for moons and other faint structures around exoplanets, and determinations of the mass of planets far from their parent stars using gravitational microlensing. New Horizons is currently in an extended mission, that will conclude in 2021, designed to survey distant objects in the Kuiper Belt at high phase angles and perform a close flyby of KBO 2014 MU69. Afterwards, the astrophysics community will have a unique, generational opportunity to use this mission for astronomical observations at heliocentric distances beyond 50 AU. In this poster, we present the science case for an extended 2021 - 2026 astrophysics mission, and discuss some of the practical considerations that must be addressed to maximize the potential science return.

Producing Distant Planets by Mutual Scattering of Planetary Embryos

NASA Astrophysics Data System (ADS)

Silsbee, Kedron; Tremaine, Scott

2018-02-01

It is likely that multiple bodies with masses between those of Mars and Earth (“planetary embryos”) formed in the outer planetesimal disk of the solar system. Some of these were likely scattered by the giant planets into orbits with semimajor axes of hundreds of au. Mutual torques between these embryos may lift the perihelia of some of them beyond the orbit of Neptune, where they are no longer perturbed by the giant planets, so their semimajor axes are frozen in place. We conduct N-body simulations of this process and its effect on smaller planetesimals in the region of the giant planets and the Kuiper Belt. We find that (i) there is a significant possibility that one sub-Earth mass embryo, or possibly more, is still present in the outer solar system; (ii) the orbit of the surviving embryo(s) typically has perihelion of 40–70 au, semimajor axis less than 200 au, and inclination less than 30° (iii) it is likely that any surviving embryos could be detected by current or planned optical surveys or have a significant effect on solar system ephemerides; (iv) whether or not an embryo has survived to the present day, its dynamical influence earlier in the history of the solar system can explain the properties of the detached disk (defined in this paper as containing objects with perihelia >38 au and semimajor axes between 80 and 500 au).

The Outer Solar System Origins Survey (OSSOS): a status update

NASA Astrophysics Data System (ADS)

Kavelaars, J. J.; Bannister, Michele T.; Gladman, Brett; Petit, Jean-Marc; Gwyn, S.; Chen, Ying-Tung Charles; Alexandersen, Mike; Volk, Kat

2015-11-01

OSSOS is a 560 hour imaging survey using MegaPrime on the CFHT designed to produce a well characterized sample of Kuiper belt objects whose orbital and physical properties will provide useful constraints on the evolutionary history of the outer solar system. Started in 2013, this 4 year project has now entered the finally year of survey operation. With 1/2 (84 square degrees) of the observation fully analyzed, OSOSS has detected and tracked 219 TNOs brighter than our typical flux limit of r' ~ 24.5. This is 30% more detections than the entire Canada-France Ecliptic Plane Survey (CFEPS), a precursor project.Based on the first quarter of the survey the OSSOS project confirms the CFEPS-L7 orbital model of the orbital structure of the TNO population (Petit et al., 2011) and has provided additional evidence of complex structure in the size distribution of scatterin TNOs (Shankman et al., 2015). A number of the OSSOS science teams are presenting results at this meeting: Bannister et al., Benecchi et al., Fraser et al., Volk et al. on a variety of aspects of the orbital and physical properties the OSSOS detected samples. Here we present a summary of the current status of the survey: field locations, basic characterization, detection rates and some global detection statistics.More details on the OSSOS project are available from our web site: www.ossos-survey.org

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pan, Margaret; Wu, Yanqin, E-mail: pan@astro.utoronto.ca

Observations in 2013 and 2014 of the Centaur 10199 Chariklo and its ring system consistently indicated that the radial width of the inner, more massive ring varies with longitude. That strongly suggests that this ring has a finite eccentricity despite the fast differential precession that Chariklo’s large quadrupole moment should induce. If the inferred apse alignment is maintained by the ring’s self-gravity, as it is for the Uranian rings, we estimate a ring mass of a few times 10{sup 16} g and a typical particle size of a few meters. These values imply a collisional spreading time of ∼10{sup 5} years,more » which is somewhat shorter than the typical Centaur dynamical lifetime of a few million years and much shorter than the age of the solar system. In light of this time constraint, we evaluate previously suggested ring formation pathways including collisional ejection and satellite disruption. We also investigate in detail a contrasting formation mechanism, the lofting of dust particles off Chariklo’s surface into orbit via outflows of sublimating CO and/or N{sub 2} triggered after Chariklo was scattered inward by giant planets. This alternate scenario predicts that rings should be common among 100 km class Centaurs but rare among Kuiper Belt objects and smaller Centaurs. It also predicts that Centaurs should show seasonal variations in cometary activity with activity maxima occurring shortly after equinox.« less

KSC-05pd2528

NASA Image and Video Library

2005-11-29

KENNEDY SPACE CENTER, FLA. - In the Vertical Integration Facility on Launch Complex 41 at Cape Canaveral Air Force Station in Florida, workers maneuver the fifth and final solid rocket booster into place for mating to the Lockheed Martin Atlas V rocket. Two of the other four rockets are seen at left. The Atlas V is the launch vehicle for the Pluto-bound New Horizons spacecraft that will make the first reconnaissance of Pluto and its moon, Charon - a "double planet" and the last planet in our solar system to be visited by spacecraft. As it approaches Pluto, the spacecraft will look for ultraviolet emission from Pluto's atmosphere and make the best global maps of Pluto and Charon in green, blue, red and a special wavelength that is sensitive to methane frost on the surface. It will also take spectral maps in the near infrared, telling the science team about Pluto's and Charon’s surface compositions and locations and temperatures of these materials. When the spacecraft is closest to Pluto or its moon, it will take close-up pictures in both visible and near-infrared wavelengths. The mission will then visit one or more objects in the Kuiper Belt region beyond Neptune. New Horizons is scheduled to launch in January 2006, swing past Jupiter for a gravity boost and scientific studies in February or March 2007, and reach Pluto and Charon in July 2015.

The tumbling rotational state of 1I/`Oumuamua

NASA Astrophysics Data System (ADS)

Fraser, Wesley C.; Pravec, Petr; Fitzsimmons, Alan; Lacerda, Pedro; Bannister, Michele T.; Snodgrass, Colin; Smolić, Igor

2018-05-01

The discovery1 of 1I/2017 U1 (1I/`Oumuamua) has provided the first glimpse of a planetesimal born in another planetary system. This interloper exhibits a variable colour within a range that is broadly consistent with local small bodies, such as the P- and D-type asteroids, Jupiter Trojans and dynamically excited Kuiper belt objects2-7. 1I/`Oumuamua appears unusually elongated in shape, with an axial ratio exceeding 5:1 (refs 1,4,5,8). Rotation period estimates are inconsistent and varied, with reported values between 6.9 and 8.3 h (refs 4-6,9). Here, we analyse all the available optical photometry data reported to date. No single rotation period can explain the exhibited brightness variations. Rather, 1I/`Oumuamua appears to be in an excited rotational state undergoing non-principal axis rotation, or tumbling. A satisfactory solution has apparent lightcurve frequencies of 0.135 and 0.126 h-1 and implies a longest-to-shortest axis ratio of ≳5:1, although the available data are insufficient to uniquely constrain the true frequencies and shape. Assuming a body that responds to non-principal axis rotation in a similar manner to Solar System asteroids and comets, the timescale to damp 1I/`Oumuamua's tumbling is at least one billion years. 1I/`Oumuamua was probably set tumbling within its parent planetary system and will remain tumbling well after it has left ours.

Results from the LCOGT Near-Earth Object Follow-up Network

NASA Astrophysics Data System (ADS)

Greenstreet, Sarah; Lister, Tim; Gomez, Edward; Christensen, Eric; Larson, Steve

2015-11-01

Las Cumbres Observatory Global Telescope Network (LCOGT) has deployed a homogeneous telescope network of nine 1-meter and two 2-meter telescopes to five locations in the northern and southern hemispheres, with plans to extend to twelve 1-meter telescopes at 6 locations. The versitility and design of this network allows for rapid response to target of opportunity events as well as the long-term monitoring of slowly changing astronomical phenomena. The network's global coverage and the apertures of telescopes available make LCOGT ideal for follow-up and characterization of Solar System objects (e.g. asteroids, Kuiper Belt Objects, comets, Near-Earth Objects (NEOs)) and ultimately for the discovery of new objects.LCOGT has completed the first phase of the deployment with the installation and commissioning of the nine 1-meter telescopes at McDonald Observatory (Texas), Cerro Tololo (Chile), SAAO (South Africa) and Siding Spring Observatory (Australia). This is complimented by the two 2-meter telescopes at Haleakala (Hawaii) and Siding Spring Observatory. The telescope network has been fully operational since May 2014, and observations are being executed remotely and robotically. Future expansion to sites in the Canary Islands and Tibet are planned for 2016.The LCOGT near-Earth object group is using the network to confirm newly detected NEO candidates produced by the major sky surveys such as Catalina Sky Survey (CSS), PanSTARRS (PS1) and NEOWISE, with several hundred targets being followed per year. Follow-up astrometry and photometry of radar-targeted objects and those on the Near-Earth Object Human Space Flight Accessible Targets Study (NHATS) or Asteroid Retrieval Mission (ARM) lists are improving orbits, producing light curves and rotation periods, and better characterizing these NEOs. Recent results include the first period determinations for several of the Goldstone-targeted NEOs. In addition, we are in the process of building a NEO portal that will allow professionals, amateurs, and Citizen Scientists to plan, schedule, and analyze NEO imaging and spectroscopy observations and data using the LCOGT Network and to act as a coordination hub for the NEO follow-up efforts.

Modeling of debris disks in Single and Binary stars

NASA Astrophysics Data System (ADS)

García, L.; Gómez, M.

2016-10-01

Infrared space observatories such as Spitzer and Herschel have allowed the detection of likely analogs to the Kuiper Belt in single as well as binary systems. The aim of this work is to characterize debris disks in single and binary stars and to identify features shared by the disks in both types of systems, as well as possible differences. We compiled a sample of 25 single and 14 binary stars (ages > 100 Myr) with flux measurements at λ >100 μm and evidence of infrared excesses attributed to the presence of debris disks. Then, we constructed and modeled the observed spectral energy distributions (SEDs), and compared the parameters of the disks of both samples. Both types of disks are relatively free of dust in the inner region (< 3-5 AU) and extend beyond 100 AU. No significant differences in the mass and dust size distributions of both samples are found.

New Thematic Solar System Exploration Products for Scientists and Educators

NASA Technical Reports Server (NTRS)

Lowes, Lesile; Wessen, Alice; Davis, Phil; Lindstrom, Marilyn

2004-01-01

The next several years are an exciting time in the exploration of the solar system. NASA and its international partners have a veritable armada of spaceships heading out to the far reaches of the solar system. We'll send the first spacecraft beyond our solar system into interstellar space. We'll launch our first mission to Pluto and the Kuiper Belt and just our second to Mercury (the first in 30 years). We'll continue our intensive exploration of Mars and begin our detailed study of Saturn and its moons. We'll visit asteroids and comets and bring home pieces of the Sun and a comet. This is truly an unprecedented period of exploration and discovery! To facilitate access to information and to provide the thematic context for these missions NASA s Solar System Exploration Program and Solar System Exploration Education Forum have developed several products.

The Outer Solar System Origin Survey full data release orbit catalog and characterization.

NASA Astrophysics Data System (ADS)

Kavelaars, J. J.; Bannister, Michele T.; Gladman, Brett; Petit, Jean-Marc; Gwyn, Stephen; Alexandersen, Mike; Chen, Ying-Tung; Volk, Kathryn; OSSOS Collaboration.

2017-10-01

The Outer Solar System Origin Survey (OSSOS) completed main data acquisition in February 2017. Here we report the release of our full orbit sample, which include 836 TNOs with high precision orbit determination and classification. We combine the OSSOS orbit sample with previously release Canada-France Ecliptic Plane Survey (CFEPS) and a precursor survey to OSSOS by Alexandersen et al. to provide a sample of over 1100 TNO orbits with high precision classified orbits and precisely determined discovery and tracking circumstances (characterization). We are releasing the full sample and characterization to the world community, along with software for conducting ‘Survey Simulations’, so that this sample of orbits can be used to test models of the formation of our outer solar system against the observed sample. Here I will present the characteristics of the data set and present a parametric model for the structure of the classical Kuiper belt.

An interstellar origin for Jupiter's retrograde co-orbital asteroid

NASA Astrophysics Data System (ADS)

Namouni, F.; Morais, M. H. M.

2018-06-01

Asteroid (514107) 2015 BZ509 was discovered recently in Jupiter's co-orbital region with a retrograde motion around the Sun. The known chaotic dynamics of the outer Solar system have so far precluded the identification of its origin. Here, we perform a high-resolution statistical search for stable orbits and show that asteroid (514107) 2015 BZ509 has been in its current orbital state since the formation of the Solar system. This result indicates that (514107) 2015 BZ509 was captured from the interstellar medium 4.5 billion years in the past as planet formation models cannot produce such a primordial large-inclination orbit with the planets on nearly coplanar orbits interacting with a coplanar debris disc that must produce the low-inclination small-body reservoirs of the Solar system such as the asteroid and Kuiper belts. This result also implies that more extrasolar asteroids are currently present in the Solar system on nearly polar orbits.

The Volatile Fraction of Comets as Quantified at Infrared Wavelengths - An Emerging Taxonomy and Implications for Natal Heritage

NASA Technical Reports Server (NTRS)

Mumma, M. J.; DiSanti, M. A.; Bonev, B. P.; Villanueva, G. L.; Magee-Sauer, K.; Gibb, E. L.; Paganini, L.; Radeva, Y. L.; Charnley, S. B.

2012-01-01

It is relatively easy to identify the reservoir from which a given comet was ejected. But dynamical models demonstrate that the main cometary reservoirs (Kuiper Belt, Oort Cloud) each contain icy bodies that formed in a range of environments in the protoplanetary disk, and the Oort Cloud may even contain bodies that formed in disks of sibling stars in the Sun s birth cluster. The cometary nucleus contains clues to the formative region(s) of its individual components. The composition of ices and rocky grains reflect a range of processes experienced by material while on the journey from the natal interstellar cloud core to the cometary nucleus. For that reason, emphasis is placed on classifying comets according to their native ices and dust (rather than orbital dynamics). Mumma & Charnley [1] reviewed the current status of taxonomies for comets and relation to their natal heritage.

Formation of Sharp Eccentric Rings in Debris Disks with Gas but Without Planets

NASA Technical Reports Server (NTRS)

Lyra, W.; Kuchner, M.

2013-01-01

'Debris disks' around young stars (analogues of the Kuiper Belt in our Solar System) show a variety of non-trivial structures attributed to planetary perturbations and used to constrain the properties of those planets. However, these analyses have largely ignored the fact that some debris disks are found to contain small quantities of gas, a component that all such disks should contain at some level. Several debris disks have been measured with a dust-to-gas ratio of about unity, at which the effect of hydrodynamics on the structure of the disk cannot be ignored. Here we report linear and nonlinear modelling that shows that dust-gas interactions can produce some of the key patterns attributed to planets. We find a robust clumping instability that organizes the dust into narrow, eccentric rings, similar to the Fomalhaut debris disk. The conclusion that such disks might contain planets is not necessarily required to explain these systems.

International Workshop on First Decadal Review of the Edgeworth-Kuiper Belt: Toward new Frontiers

NASA Astrophysics Data System (ADS)

Hainaut, O.

2003-06-01

On March 11 to 14, 2003, an international conference on the Minor Bodies in the Outer Solar System was held in Antofagasta, Chile. The conference, which was organized by ESO and Universidad Catolica del Norte (UCN) of Antofagasta, gathered about 70 participants from 20 countries. Originally, it was supposed to take place on the UCN campus. However, a student strike forced us to relocate at the last minute to the Carrera Club Hotel. Thanks to the efforts of A. Lagarini, the conference secretary (and ESO/Chile Science secretary) and to the Hotel staff, this did not cause any disruption. The traditional group photo (opposite) was shot in front of the Geological Museum of UCN. This short summary highlights some of the results presented at this conference; the proceedings, which are currently being edited, will be published as a special issue of “Earth, Moon and Planets.”

Comfort and convenience specifications for safety belts : shoulder belt fit, pressure and pullout forces

DOT National Transportation Integrated Search

1980-04-30

A three-part study was conducted to further define comfort requirements for seat belt systems with respect to shoulder belt fit, shoulder belt contact pressure, and 3-point restraint system pullout forces. Objective of the belt-fit portion of the stu...

Colors and Compositional Characteristics of Kuiper Belt Objects and Centaurs

NASA Astrophysics Data System (ADS)

Lederer, S. M.; Vilas, F.; Jarvis, K. S.; French, L.

2001-11-01

We present a study designed by Painter et al. (DPS 2000) to search for evidence of aqueous alteration in the surface material of solar system objects. Using VRI broadband photometry, we will search for the presence of the 0.7 um absorption feature (indicative of Fe-bearing hydrated silicates) in KBOs and Centaurs. Vilas (Icarus 111, 1994) found a strong correlation between the presence of the 0.7-um feature in low-albedo asteroids with solar-like colors and the 3-um water of hydration feature, indicative of phyllosilicates. Recent work by Howell et al. (LPSC, 2001) confirms that the presence of the 0.7 um feature in low-albedo asteroids definitely indicates the presence of the 3.0-um water of hydration absorption feature, suggesting the action of aqueous alteration in asteroids. In addition, Feierberg et al. (Icarus 63, 1985) showed that when the U - B color difference is > 0.12 in ECAS photometry, the 3.0-um absorption feature is often present in low albedo asteroids. Therefore, if the U-B color difference is > 0.12 and the 0.7-um feature is present in UBVRI reflectance photometry, water of hydration is implied in KBOs and Centaurs. We pursue these studies based on the mixed flat or steeply reddened photometry of these objects: Water ice has been identified in near-IR dark, flat spectra of some Centaurs, providing a source for the action of aqueous alteration. The complex collisional history proposed for these objects suggests a potential source of heating that would melt water ice, providing a mechanism for aqueous alteration to occur. Finally, we will use BVR photometry to determine the B-V and V-R colors, as has been done by Tegler and Romanishin (Nature, 407). We will compare our results with colors of KBOs and Centaurs published in the literature. This research was supported by the National Research Council and the NASA Planetary Astronomy Program.

Belt conveyor apparatus

DOEpatents

Oakley, David J.; Bogart, Rex L.

1987-01-01

A belt conveyor apparatus according to this invention defines a conveyance path including a first pulley and at least a second pulley. An endless belt member is adapted for continuous travel about the pulleys and comprises a lower portion which engages the pulleys and an integral upper portion adapted to receive objects therein at a first location on said conveyance path and transport the objects to a second location for discharge. The upper belt portion includes an opposed pair of longitudinally disposed crest-like members, biased towards each other in a substantially abutting relationship. The crest-like members define therebetween a continuous, normally biased closed, channel along the upper belt portion. Means are disposed at the first and second locations and operatively associated with the belt member for urging the normally biased together crest-like members apart in order to provide access to the continuous channel whereby objects can be received into, or discharged from the channel. Motors are in communication with the conveyance path for effecting the travel of the endless belt member about the conveyance path. The conveyance path can be configured to include travel through two or more elevations and one or more directional changes in order to convey objects above, below and/or around existing structures.

The twofold debris disk around HD 113766 A. Warm and cold dust as seen with VLTI/MIDI and Herschel/PACS

NASA Astrophysics Data System (ADS)

Olofsson, J.; Henning, Th.; Nielbock, M.; Augereau, J.-C.; Juhàsz, A.; Oliveira, I.; Absil, O.; Tamanai, A.

2013-03-01

Context. Warm debris disks are a sub-sample of the large population of debris disks, and display excess emission in the mid-infrared. Around solar-type stars, very few objects (~2% of all debris disks) show emission features in mid-IR spectroscopic observations that are attributed to small, warm silicate dust grains. The origin of this warm dust could be explained either by a recent catastrophic collision between several bodies or by transport from an outer belt similar to the Kuiper belt in the solar system. Aims: We present and analyze new far-IR Herschel/PACS photometric observations, supplemented by new and archival ground-based data in the mid-IR (VLTI/MIDI and VLT/VISIR), for one of these rare systems: the 10-16 Myr old debris disk around HD 113766 A. We improve an existing model to account for these new observations. Methods: We implemented the contribution of an outer planetesimal belt in the Debra code, and successfully used it to model the spectral energy distribution (SED) as well as complementary observations, notably MIDI data. We better constrain the spatial distribution of the dust and its composition. Results: We underline the limitations of SED modeling and the need for spatially resolved observations. We improve existing models and increase our understanding of the disk around HD 113766 A. We find that the system is best described by an inner disk located within the first AU, well constrained by the MIDI data, and an outer disk located between 9-13 AU. In the inner dust belt, our previous finding of Fe-rich crystalline olivine grains still holds. We do not observe time variability of the emission features over at least an eight-year time span in an environment subjected to strong radiation pressure. Conclusions: The time stability of the emission features indicates that μm-sized dust grains are constantly replenished from the same reservoir, with a possible depletion of sub- μm-sized grains. We suggest that the emission features may arise from multi-composition aggregates. We discuss possible scenarios concerning the origin of the warm dust observed around HD 113766 A. The compactness of the innermost regions as probed by the MIDI visibilities and the dust composition suggest that we are witnessing the results of (at least) one collision between partially differentiated bodies, in an environment possibly rendered unstable by terrestrial planetary formation. Based on Herschel observations, OBSIDs: 1342227026, 1342227027, 1342237934, and 1342237935. Herschel is an ESA space observatory with science instruments provided by European-led Principal Investigator consortia and with important participation from NASA. Based on VISIR observations collected at the VLT (European Southern Observatory, Paranal, Chile) with program 089.C-0322(A).

A mission concept for a Grand Tour of Multiple Asteroid Systems

NASA Astrophysics Data System (ADS)

Marchis, F.; Dankanich, J.; Tricarico, P.; Bellerose, J.

2009-12-01

In 1993, the Galileo spacecraft imaged the first companion of asteroid, Dactyl orbiting 243 Ida, a main-belt asteroid. Since then, discoveries have been accumulated thanks to the development of high angular resolution imaging on ground-based telescopes (adaptive optics), radar observations and accurate photometric light curve measurements. To date, 180 companions of small solar system bodies (SSSBs) are known in various populations, including 100 in the asteroid main belt, 33 Near Earth Asteroids, 4 Jupiter-Trojan asteroids and 44 in the Kuiper Belt. Multiple Asteroids have been shown to be complex worlds in their own with a wide range of morphologies, dynamical histories, and structural evolution. To the exception of 243 Ida, no spacecraft has visited any of them. Investigating binary asteroid systems can verify and validate current theories on their formation and on the influence of the sun in their formation (YORP effect) and evolution (space weathering). In particular, assessing the origin of the secondary satellite, if it is of common origin or capture, can provide clue of their formation. To a larger extend, the determination of their nature, scenario formation and evolution are key to understand how planet formation occurred but also to understand i) the population and compositional structure of the SSSB today ii) how the dynamics and collisions modify this structure over time iii) what the physical properties of asteroids are (density, porosity) iv) how the surface modification processes affect our ability to determine this structure (e.g. space weathering). In addition, being able to study these properties on closeby asteroids will give a relative scale accounting for the sizes, shape, rotation periods and cratering rate of these small and young bodies. In the framework of the NASA Discovery program, we propose a mission consisting of a Grand Tour of several multiple asteroid systems, including the flyby of a near earth binary asteroid and the rendezvous with several multiple asteroid systems located in the main belt. This mission concept uses the NASA's evolutionary Xenon Thruster (NEXT), the second generation of electric propulsion with 3 times more input power than the previous generation (NSTAR) of the Dawn mission. The mission objectives for each rendezvous asteroid are i) the characterization of the surface geology by direct imaging in visible and thermal infrared spectroscopy, ii) the characterization of the shape and gravity coupling visible observations with LIDAR ranging data, iii) the determination of the thermophysical properties of the surface, and iv) the identification of the surface composition by visible and near-infrared spectroscopy. The trajectory, science package and mission operations of the mission will be described. This work is supported by the National Science Foundation 05-608, "Astronomy and Astrophysics Research Grants (AAG)" No AST-0807468

Mutual gravitational potential, force, and torque of a homogeneous polyhedron and an extended body: an application to binary asteroids

NASA Astrophysics Data System (ADS)

Shi, Yu; Wang, Yue; Xu, Shijie

2017-11-01

Binary systems are quite common within the populations of near-Earth asteroids, main-belt asteroids, and Kuiper belt asteroids. The dynamics of binary systems, which can be modeled as the full two-body problem, is a fundamental problem for their evolution and the design of relevant space missions. This paper proposes a new shape-based model for the mutual gravitational potential of binary asteroids, differing from prior approaches such as inertia integrals, spherical harmonics, or symmetric trace-free tensors. One asteroid is modeled as a homogeneous polyhedron, while the other is modeled as an extended rigid body with arbitrary mass distribution. Since the potential of the polyhedron is precisely described in a closed form, the mutual gravitational potential can be formulated as a volume integral over the extended body. By using Taylor expansion, the mutual potential is then derived in terms of inertia integrals of the extended body, derivatives of the polyhedron's potential, and the relative location and orientation between the two bodies. The gravitational forces and torques acting on the two bodies described in the body-fixed frame of the polyhedron are derived in the form of a second-order expansion. The gravitational model is then used to simulate the evolution of the binary asteroid (66391) 1999 KW4, and compared with previous results in the literature.

Probable Disastrous Consequences of Collision Between Unknown Small (100 m) Asteroids with Known (Approximately 1 km) Near Earth Orbiting (NEO) Asteroids

NASA Technical Reports Server (NTRS)

Smalley, Larry

2003-01-01

The long-term stability of the Solar System is not well understood. Ironically its stability is taken for granted even though our knowledge of all the constituents [comets, asteroids. (The Asteroid Belt between Mars and Jupiter, Trojan Asteroids, Kuiper belt, Ort Cloud), planetoids, planets, moons, etc], and its long-term dynamics cannot be easily computed. At best one might say that the solar system is chaotic, but much of the time it seems to exists near a quasi-stationary state. An asteroid that passes near the Earth regularly returns with clock-like precision. Taking into account every known detail of its path through the solar system, its orbit is calculated forward thousands of years with no untoward calamity on the horizon. And then one day, this passive visitor slams into the Earth during a sunny afternoon picnic! Can this happen? Unfortunately, this is a real possibility in the ordinary history of the solar system. In fact our knowledge of the solar system in the small is sketchy, as will be pointed out. Events, which lie outside our awareness, can precipitate disasters that we may perceive when it's too late to launch effective counter measures. In this work, one such scenario is described and the direct consequences for the Earth are calculated.