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Sample records for jupiter explains lack

  1. Jupiter's Gossamer Rings Explained.

    NASA Astrophysics Data System (ADS)

    Hamilton, D. P.

    2003-05-01

    Over the past several years, Galileo measurements and groundbased imaging have drastically improved our knowledge of Jupiter's faint ring system. We now recognize that the ring consists of four components: a main ring 7000km wide, whose inner edge blossoms into a vertically-extended halo, and a pair of more tenuous Gossamer rings, one associated with each of the small moons Thebe and Amalthea. When viewed edge on, the Gossamer rings appear as diaphanous disks whose thicknesses agree with the vertical excursions of the inclined satellites from the equatorial plane. In addition, the brightness of each Gossamer ring drops off sharply outside the satellite orbits. These correlations allowed Burns etal (1999, Science, 284, 1146) to argue convincingly that the satellites act as sources of the dusty ring material. In addition, since most material is seen inside the orbits of the source satellites, an inwardly-acting dissipative force such as Poynting-Robertson drag is implicated. The most serious problem with this simple and elegant picture is that it is unable to explain the existence of a faint swath of material that extends half a jovian radius outward from Thebe. A key constraint is that this material has the same thickness as the rest of the Thebe ring. In this work, we identify the mechanism responsible for the outward extension: it is a shadow resonance, first investigated by Horanyi and Burns (1991, JGR, 96, 19283). When a dust grain enters Jupiter's shadow, photoelectric processes shut down and the grain's electric charge becomes more negative. The electromagnetic forces associated with the varying charge cause periodic oscillations in the orbital eccentricity and semimajor axis as the orbital pericenter precesses. This results in a ring which spreads both inward and outward of its source satellite while preserving its vertical thickness - just as is observed for the Thebe ring. Predictions of the model are: i) gaps of micron-sized material interior to Thebe and

  2. Jumping Jupiter Can Explain Mercury’s Orbit

    NASA Astrophysics Data System (ADS)

    Roig, Fernando; Nesvorný, David; DeSouza, Sandro Ricardo

    2016-04-01

    The orbit of Mercury has large values of eccentricity and inclination that cannot be easily explained if this planet formed on a circular and coplanar orbit. Here, we study the evolution of Mercury’s orbit during the instability related to the migration of the giant planets in the framework of the jumping-Jupiter model. We found that some instability models are able to produce the correct values of Mercury’s eccentricity and inclination, provided that relativistic effects are included in the precession of Mercury’s perihelion. The orbital excitation is driven by the fast change of the normal oscillation modes of the system corresponding to the perihelion precession of Jupiter (for the eccentricity) and the nodal regression of Uranus (for the inclination).

  3. Jupiter

    NASA Astrophysics Data System (ADS)

    Simon, Seymour

    Describes the characteristics of the planet Jupiter and its moons as revealed by photographs sent back by two unmanned Voyager spaceships which took one-and-one half years to reach this distant giant.

  4. Jupiter

    NASA Astrophysics Data System (ADS)

    Encrenaz, T.; Murdin, P.

    2002-10-01

    At 5.2 AU from the Sun (table 1), Jupiter is the closest and the most massive of the GIANT PLANETS, which extend in the outer solar system up to heliocentric distances of 30 AU. Its mass amounts to 318 terrestrial masses, and its diameter is 11 times the terrestrial one (table 2). Like the other giant planets, Jupiter has a low density (1.31 g cm-3) which reflects its chemical composition, mostly ...

  5. Jupiter

    NASA Image and Video Library

    1998-06-04

    This processed color image of Jupiter was produced in 1990 by the U.S. Geological Survey from a Voyager image captured in 1979. Zones of light-colored, ascending clouds alternate with bands of dark, descending clouds. http://photojournal.jpl.nasa.gov/catalog/PIA00343

  6. Jupiter

    NASA Astrophysics Data System (ADS)

    Bagenal, Fran; Dowling, Timothy E.; McKinnon, William B.

    2007-03-01

    Preface; 1. Introduction F. Bagenal, T. E. Dowling and W. B. McKinnon; 2. The origin of Jupiter J. I. Lunine, A. Corandini, D. Gautier, T. C. Owen and G. Wuchterl; 3. The interior of Jupiter T. Guillot, D. J. Stevenson, W. B. Hubbard and D. Saumon; 4. The composition of the atmosphere of Jupiter F. W. Taylor, S. K. Atreya, Th. Encrenaz, D. M. Hunten, P. G. J. Irwin and T. C. Owen; 5. Jovian clouds and haze R. A. West, K. H. Baines, A. J. Friedson, D. Banfield, B. Ragent and F. W. Taylor; 6. Dynamics of Jupiter's atmosphere A. P. Ingersoll, T. E. Dowling, P. J. Gierasch, G. S. Orton, P. L. Read, A. Sánchez-Lavega, A. P. Showman, A. A. Simon-Miller and A. R. Vasavada; 7. The stratosphere of Jupiter J. I. Moses, T. Fouchet, R. V. Yelle, A. J. Friedson, G. S. Orton, B. Bézard, P. Drossart, G. R. Gladstone, T. Kostiuk and T. A. Livengood; 8. Lessons from Shoemaker-Levy 9 about Jupiter and planetary impacts J. Harrington, I. de Pater, S. H. Brecht, D. Deming, V. Meadows, K. Zahnle and P. D. Nicholson; 9. Jupiter's thermosphere and ionosphere R. V. Yelle and S. Miller; 10. Jovian dust: streams, clouds and rings H. Krüger, M. Horányi, A. V. Krivov and A. L. Graps; 11. Jupiter's ring-moon system J. A. Burns, D. P. Simonelli, M. R. Showalter, D. P. Hamilton, C. C. Porco, H. Throop and L. W. Esposito; 12. Jupiter's outer satellites and trojans D. C. Jewitt, S. Sheppard and C. Porco; 13. Interior composition, structure and dynamics of the Galilean satellites G. Schubert, J. D. Anderson, T. Spohn and W. B. McKinnon; 14. The lithosphere and surface of Io A. S. McEwen, L. P. Keszthelyi, R. Lopes, P. M. Schenk and J. R. Spencer; 15. Geology of Europa R. Greeley, C. F. Chyba, J. W. Head III, T. B. McCord, W. B. McKinnon, R. T. Pappalardo and P. Figueredo; 16. Geology of Ganymede R. T. Pappalardo, G. C. Collins, J. W. Head III, P. Helfenstein, T. B. McCord, J. M. Moore, L. M. Procktor, P. M. Shenk and J. R. Spencer; 17. Callisto J. M. Moore, C. R. Chapman. E. B. Bierhaus, R

  7. CROWDING-OUT OF GIANTS BY DWARFS: AN ORIGIN FOR THE LACK OF COMPANION PLANETS IN HOT JUPITER SYSTEMS

    SciTech Connect

    Ogihara, Masahiro; Inutsuka, Shu-ichiro; Kobayashi, Hiroshi

    2013-11-20

    We investigate the formation of close-in terrestrial planets from planetary embryos under the influence of a hot Jupiter (HJ) using gravitational N-body simulations that include gravitational interactions between the gas disk and the terrestrial planet (e.g., type I migration). Our simulations show that several terrestrial planets efficiently form outside the orbit of the HJ, making a chain of planets, and all of them gravitationally interact directly or indirectly with the HJ through resonance, which leads to inward migration of the HJ. We call this mechanism of induced migration of the HJ ''crowding-out''. The HJ is eventually lost through collision with the central star, and only several terrestrial planets remain. We also find that the efficiency of the crowding-out effect depends on the model parameters; for example, the heavier the disk is, the more efficient the crowding-out is. When planet formation occurs in a massive disk, the HJ can be lost to the central star and is never observed. On the other hand, for a less massive disk, the HJ and terrestrial planets can coexist; however, the companion planets may be below the detection limit of current observations. In both cases, systems with a HJ and terrestrial planets have little chance of detection. Therefore, our model naturally explains the lack of companion planets in HJ systems regardless of the disk mass. In effect, our model provides a theoretical prediction for future observations; additional planets can be discovered just outside the HJ, and their masses should generally be small.

  8. Lost in Jupiter's Shadow: Can Resonant Charge Variations Explain Dust Grain Sizes in the Main Ring?

    NASA Astrophysics Data System (ADS)

    Jontof-Hutter, Daniel; Hamilton, D. P.

    2012-10-01

    Interplanetary impacts onto the tiny moons Metis and Adrastea replenish Jupiter's main ring with dusty ejecta of all sizes. The equilibrium size distribution present in the rings at a given time is a function of production and loss mechanisms, both of which may be vary with particle size. Loss mechanisms include collisions and dynamical processes. Here we explore some of the latter. Grains tend to pick up negative electric charges due to motion through Jupiter's plasma environment, and positive charges from the photoelectric effect of sunlight. The periodic interruption of sunlight in Jupiter's shadow causes the equilibrium electric charge, and hence the Lorentz force, to resonate with the Kepler orbital frequency. The eccentricity increases for grains moving radially inwards during the shadow transit, and decreases when grains move outward in the shadow, hence the azimuthal location of pericenter is important. For smaller grains, the eccentricity increases monotonically until they collide with Jupiter. For much larger grains, precession due to both the Lorentz force and planetary oblateness causes the eccentricity to oscillate periodically. We explore the shadow instability in the main ring for a variety of uniform plasma density models, comparing numerical data with a semi-analytic approximation. We find that the effect of the shadow dwindles in importance for plasma that is either too sparse or too dense. In sparse plasma, the charging timescale slows, limiting the change in electric potential from sunlight to shadow. In dense plasma, charging currents from the plasma overwhelm the photoelectric effect in sunlight, also resulting in a small change in electric potential. Between these two regimes, the shadow resonance efficiently removes grains up to a particular size threshold in the main ring. This size-dependent loss mechanism may contribute to the observed flattening in the size distribution index for smaller grains.

  9. Close-in planets around giant stars. Lack of hot-Jupiters and prevalence of multiplanetary systems

    NASA Astrophysics Data System (ADS)

    Lillo-Box, J.; Barrado, D.; Correia, A. C. M.

    2016-05-01

    Extrasolar planets abound in almost any possible configuration. However, until five years ago, there was a lack of planets orbiting closer than 0.5 au to giant or subgiant stars. Since then, recent detections have started to populated this regime by confirming 13 planetary systems. We discuss the properties of these systems in terms of their formation and evolution off the main sequence. Interestingly, we find that 70.0 ± 6.6% of the planets in this regime are inner components of multiplanetary systems. This value is 4.2σ higher than for main-sequence hosts, which we find to be 42.4 ± 0.1%. The properties of the known planets seem to indicate that the closest-in planets (a< 0.06 au) to main-sequence stars are massive (i.e., hot Jupiters) and isolated and that they are subsequently engulfed by their host as it evolves to the red giant branch, leaving only the predominant population of multiplanetary systems in orbits 0.06 Jupiters.

  10. Can Sulfur Explain the Bimodal Color Distribution Observed in the Jupiter Trojans?

    NASA Astrophysics Data System (ADS)

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

    2016-10-01

    We present a series of experiments aimed at exploring the hypothesis that the presence or absence of H2S ice on the surface of primitive icy bodies in the early solar system is responsible for the bimodal color distribution of the Jupiter Trojans.Central to our proposed hypothesis is a location-dependent sublimation of ices in the primordial trans-neptunian disk which would have divided objects according to whether they retained H2S on their surfaces for sufficient time to incorporate their constituents into irradiated organic crusts. The irradiated crusts of objects with and without H2S would have different chemistry and therefore different optical properties. Dynamical instability models of the early solar system (e.g. Morbidelli et al., 2005, Nesvorny et al., 2013) predict that Trojans, formed from this primordial population, were later emplaced inward to co-orbit with Jupiter during large-scale rearrangement events. According to our hypothesis, the Trojans today would show evidence of their primordial location with respect to the H2S sublimation line in the form of a bimodal distribution in surface chemistry, and thus color.We present laboratory spectroscopy experiments in support of this hypothesis. Numerous thin ice films composed of H2O, CH3OH, NH3, were produced both with and without H2S. Subsequent processing of these icy bodies was simulated using electron irradiation and heating. Visible reflectance spectra show significant reddening when H2S is present. Mid-infrared spectra confirm the formation of non-volatile sulfur-containing molecules in the products of H2S-containing ices. The infrared spectral properties of the organic residues remaining at room temperature show that sulfur significantly changes the chemistry of these irradiation-produced organics. These experiments suggest that the presence of specific sulfur-bearing chemical species may play an important role in the colors of both the KBOs and Trojans today. This testable hypothesis could feed

  11. HST hot-Jupiter transmission spectral survey: evidence for aerosols and lack of TiO in the atmosphere of WASP-12b

    NASA Astrophysics Data System (ADS)

    Sing, D. K.; Lecavelier des Etangs, A.; Fortney, J. J.; Burrows, A. S.; Pont, F.; Wakeford, H. R.; Ballester, G. E.; Nikolov, N.; Henry, G. W.; Aigrain, S.; Deming, D.; Evans, T. M.; Gibson, N. P.; Huitson, C. M.; Knutson, H.; Showman, A. P.; Vidal-Madjar, A.; Wilson, P. A.; Williamson, M. H.; Zahnle, K.

    2013-12-01

    plausible dust aerosol. The presence of atmospheric aerosols also helps to explain the modestly bright albedo implied by Spitzer observations, as well as the near blackbody nature of the emission spectrum. Ti-bearing condensates on the cooler night-side is the most natural explanation for the overall lack of TiO signatures in WASP-12b, indicating the day/night cold trap is an important effect for very hot Jupiters. These findings indicate that aerosols can play a significant atmospheric role for the entire wide range of hot-Jupiter atmospheres, potentially affecting their overall spectrum and energy balance.

  12. The meteorology of Jupiter

    NASA Technical Reports Server (NTRS)

    Ingersoll, A. P.

    1976-01-01

    From the point of view of meteorology the most important differences between Jupiter and the earth are related to the fact that Jupiter has an appreciable internal energy source and probably lacks a solid surface. The composition and vertical structure of the Jovian atmosphere is considered along with the composition of Jovian cloud particles, turbulence in Jupiter's atmosphere, data on the horizontal structure and motions of the atmosphere, and questions related to the longevity of Jupiter's clouds. Attention is given to the barotropic characteristics of Jupiter's atmosphere, the radiation balance in the atmosphere of the earth and of Jupiter, and studies of the Great Red Spot.

  13. The Scots' Paradox: can sun exposure, or lack of it, explain major paradoxes in epidemiology?

    PubMed

    Gillie, Oliver

    2012-01-01

    Five epidemiological paradoxes that have puzzled epidemiologists for a decade or more can be explained by the UVB-vitamin D hypothesis. The Scots' Paradox is examined in detail as an example. Many subsidiary factors varying over time and place influence the amount of UVB which reaches the skin of individuals and so the amount of vitamin D synthesised, while other factors influence the amount ingested. These factors are plotted leading to a common pathway that ends in vitamin D insufficiency and consequent disease. Examples suggest that the factors interact to increase mortality in Scotland in a way consistent with causation according to the criteria of Bradford Hill. It is suggested that different degrees of vitamin D insufficiency in populations can explain important differences in the health of nations and resolve health paradoxes. The analysis also shows that vitamin D insufficiency is a consequence of industrialisation and, like other consequences of industrial growth, such as water and air pollution, needs to be corrected by public health measures. Direct intervention with use of supplements and fortification of foods with vitamin D can be expected to provide considerable health gains, but progress will be slow until there is greater recognition of the vitamin D health crisis by the public, professionals and politicians. Health professionals need to be trained and motivated to encourage use of supplements, particularly by pregnant and nursing mothers, and infants. The importance of open sunny spaces and clean air that allows full penetration of UVB needs to be recognised by city planners and politicians. New advice and new fashions are needed to encourage maximum exposure of skin to summer sun without burning. Use of sunlamps to boost vitamin D synthesis could be useful.

  14. A possible mechanism to explain the lack of binary asteroids among the Plutinos

    NASA Astrophysics Data System (ADS)

    Compère, A.; Farrelly, D.; Lemaître, A.; Hestroffer, D.

    2013-10-01

    Context. Binary asteroids are common in the solar system, including in the Kuiper belt. However, there seems to be a marked disparity between the binary populations in the classical part of the Kuiper belt and the part of the belt in the 3:2 resonance with Neptune - i.e., the region inhabited by the Plutinos. In particular, binary Plutinos are extremely rare. Aims: We study the impact of the 3:2 resonance on the formation of Kuiper belt binaries, according to the Nice model, in order to explain such phenomenon. Methods: Numerical simulations are performed within the 2 + 2 body approximation (Sun/Neptune + binary partners). The MEGNO chaos indicator is used to map out regular and chaotic regions of phase space. Residence times of test (binary) particles within the Hill sphere are compared inside and outside of the 3:2 resonance. The effect of increasing the heliocentric eccentricity of the centre of mass of the binary system is studied. This is done because mean-motion resonances between a planet and an asteroid usually have the effect of increasing the eccentricity of the asteroid. Results: The stable zones in the MEGNO maps are mainly disrupted in the resonant, eccentric case: the number of binary asteroids created in this case is significantly lower than outside the 3:2 resonance. Conclusions: In the 2 + 2 body approximation, the pumping of the eccentricity of the centre of mass of a potential binary destabilises the formation of binaries. This may be a factor in explaining the scarcity of binaries in the Plutino population.

  15. Erupted frothy xenoliths may explain lack of country-rock fragments in plutons

    PubMed Central

    Burchardt, Steffi; Troll, Valentin R.; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

    2016-01-01

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as “xenolith graveyards”, or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material. PMID:27804996

  16. Erupted frothy xenoliths may explain lack of country-rock fragments in plutons.

    PubMed

    Burchardt, Steffi; Troll, Valentin R; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

    2016-11-02

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as "xenolith graveyards", or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material.

  17. Erupted frothy xenoliths may explain lack of country-rock fragments in plutons

    NASA Astrophysics Data System (ADS)

    Burchardt, Steffi; Troll, Valentin R.; Schmeling, Harro; Koyi, Hemin; Blythe, Lara

    2016-11-01

    Magmatic stoping is discussed to be a main mechanism of magma emplacement. As a consequence of stoping, abundant country-rock fragments should occur within, and at the bottom of, magma reservoirs as “xenolith graveyards”, or become assimilated. However, the common absence of sufficient amounts of both xenoliths and crustal contamination have led to intense controversy about the efficiency of stoping. Here, we present new evidence that may explain the absence of abundant country-rock fragments in plutons. We report on vesiculated crustal xenoliths in volcanic rocks that experienced devolatilisation during heating and partial melting when entrained in magma. We hypothesise that the consequential inflation and density decrease of the xenoliths allowed them to rise and become erupted instead of being preserved in the plutonic record. Our thermomechanical simulations of this process demonstrate that early-stage xenolith sinking can be followed by the rise of a heated, partially-molten xenolith towards the top of the reservoir. There, remnants may disintegrate and mix with resident magma or erupt. Shallow-crustal plutons emplaced into hydrous country rocks may therefore not necessarily contain evidence of the true amount of magmatic stoping during their emplacement. Further studies are needed to quantify the importance of frothy xenolith in removing stoped material.

  18. Inherent directionality explains the lack of feedback loops in empirical networks

    PubMed Central

    Domínguez-García, Virginia; Pigolotti, Simone; Muñoz, Miguel A.

    2014-01-01

    We explore the hypothesis that the relative abundance of feedback loops in many empirical complex networks is severely reduced owing to the presence of an inherent global directionality. Aimed at quantifying this idea, we propose a simple probabilistic model in which a free parameter γ controls the degree of inherent directionality. Upon strengthening such directionality, the model predicts a drastic reduction in the fraction of loops which are also feedback loops. To test this prediction, we extensively enumerated loops and feedback loops in many empirical biological, ecological and socio-technological directed networks. We show that, in almost all cases, empirical networks have a much smaller fraction of feedback loops than network randomizations. Quite remarkably, this empirical finding is quantitatively reproduced, for all loop lengths, by our model by fitting its only parameter γ. Moreover, the fitted value of γ correlates quite well with another direct measurement of network directionality, performed by means of a novel algorithm. We conclude that the existence of an inherent network directionality provides a parsimonious quantitative explanation for the observed lack of feedback loops in empirical networks. PMID:25531727

  19. Inherent directionality explains the lack of feedback loops in empirical networks.

    PubMed

    Domínguez-García, Virginia; Pigolotti, Simone; Muñoz, Miguel A

    2014-12-22

    We explore the hypothesis that the relative abundance of feedback loops in many empirical complex networks is severely reduced owing to the presence of an inherent global directionality. Aimed at quantifying this idea, we propose a simple probabilistic model in which a free parameter γ controls the degree of inherent directionality. Upon strengthening such directionality, the model predicts a drastic reduction in the fraction of loops which are also feedback loops. To test this prediction, we extensively enumerated loops and feedback loops in many empirical biological, ecological and socio-technological directed networks. We show that, in almost all cases, empirical networks have a much smaller fraction of feedback loops than network randomizations. Quite remarkably, this empirical finding is quantitatively reproduced, for all loop lengths, by our model by fitting its only parameter γ. Moreover, the fitted value of γ correlates quite well with another direct measurement of network directionality, performed by means of a novel algorithm. We conclude that the existence of an inherent network directionality provides a parsimonious quantitative explanation for the observed lack of feedback loops in empirical networks.

  20. Age associated low mitochondrial biogenesis may be explained by lack of response of PGC-1α to exercise training.

    PubMed

    Derbré, Frederic; Gomez-Cabrera, Mari Carmen; Nascimento, Ana Lucia; Sanchis-Gomar, Fabian; Martinez-Bello, Vladimir Essau; Tresguerres, Jesus A F; Fuentes, Teresa; Gratas-Delamarche, Arlette; Monsalve, Maria; Viña, Jose

    2012-06-01

    Low mitochondriogenesis is critical to explain loss of muscle function in aging and in the development of frailty. The aim of this work was to explain the mechanism by which mitochondriogenesis is decreased in aging and to determine to which extent it may be prevented by exercise training. We used aged rats and compared them with peroxisome proliferator-activated receptor-γ coactivator-1α deleted mice (PGC-1α KO). PGC-1α KO mice showed a significant decrease in the mitochondriogenic pathway in muscle. In aged rats, we found a loss of exercise-induced expression of PGC-1α, nuclear respiratory factor-1 (NRF-1), and of cytochrome C. Thus muscle mitochondriogenesis, which is activated by exercise training in young animals, is not in aged or PGC-1α KO ones. Other stimuli to increase PGC-1α synthesis apart from exercise training, namely cold induction or thyroid hormone treatment, were effective in young rats but not in aged ones. To sum up, the low mitochondrial biogenesis associated with aging may be due to the lack of response of PGC-1α to different stimuli. Aged rats behave as PGC-1α KO mice. Results reported here highlight the role of PGC-1α in the loss of mitochondriogenesis associated with aging and point to this important transcriptional coactivator as a target for pharmacological interventions to prevent age-associated sarcopenia.

  1. Jupiter Eruptions

    NASA Image and Video Library

    2008-01-25

    NASA Hubble Space Telescope shows detailed analysis of two continent-sized storms that erupted in Jupiter atmosphere in March 2007 shows that Jupiter internal heat plays a significant role in generating atmospheric disturbances .

  2. Jupiter Wallpaper

    NASA Image and Video Library

    2017-03-08

    When team members from NASA's Juno mission invited the public to process JunoCam images, they did not anticipate that they would receive back such beautiful, creative expressions of art. The oranges and grayed-out regions of blue-green in this tiled and color-enhanced image resemble a color scheme much like Romantic era paintings, but more abstract. The lack of discreet objects to focus on allows the mind to seek familiar Earthly shapes, and the brightest spots seem to draw the eye. Citizen scientist Eric Jorgensen created this Jovian artwork with a JunoCam image taken when the spacecraft was at an altitude of 11,100 miles (17,800 kilometers) above Jupiter's cloudtops on Dec. 11, 2016 at 9:22 a.m. PT (12:22 p.m. ET). http://photojournal.jpl.nasa.gov/catalog/PIA21385

  3. Verbal/social autopsy study helps explain the lack of decrease in neonatal mortality in Niger, 2007–2010

    PubMed Central

    Kalter, Henry D; Yaroh, Asma Gali; Maina, Abdou; Koffi, Alain K; Bensaïd, Khaled; Amouzou, Agbessi; Black, Robert E

    2016-01-01

    Background This study was one of a set of verbal/social autopsy (VASA) investigations undertaken by the WHO/UNICEF–supported Child Health Epidemiology Reference Group to estimate the causes and determinants of neonatal and child deaths in high priority countries. The study objective was to help explain the lack of decrease in neonatal mortality in Niger from 2007 to 2010, a period during which child mortality was decreasing. Methods VASA interviews were conducted of a random sample of 453 neonatal deaths identified by the 2010 Niger National Mortality Survey (NNMS). Causes of death were determined by expert algorithm analysis, and the prevalence of household, community and health system determinants were examined along the continuum of maternal and newborn care, the Pathway to Survival for newborn illnesses, and an extended pathway for maternal complications. The social autopsy findings were compared to available data for survivors from the same cohort collected by the NNMS and the 2012 Niger Demographic and Health Survey. Findings Severe neonatal infection and birth asphyxia were the leading causes of early neonatal death in the community and facilities. Death in the community after delayed careseeking for severe infection predominated during the late neonatal period. The levels of nearly all demographic, antenatal and delivery care factors were in the direction of risk for the VASA study decedents. They more often resided rurally (P < 0.001) and their mothers were less educated (P = 0.03) and gave birth when younger (P = 0.03) than survivors’ mothers. Their mothers also were less likely to receive quality antenatal care (P < 0.001), skilled attendance at birth (P = 0.03) or to deliver in an institution (P < 0.001). Nearly half suffered an obstetric complication, with more maternal infection (17.9% vs 0.2%), antepartum hemorrhage (12.5% vs 0.5%) and eclampsia/preeclampsia (9.5% vs 1.6%) than for all births in Niger. Their mothers also

  4. A lack of functional NK1 receptors explains most, but not all, abnormal behaviours of NK1R-/- mice1

    PubMed Central

    Porter, A J; Pillidge, K; Tsai, Y C; Dudley, J A; Hunt, S P; Peirson, S N; Brown, L A; Stanford, S C

    2015-01-01

    Mice lacking functional neurokinin-1 receptors (NK1R-/-) display abnormal behaviours seen in Attention Deficit Hyperactivity Disorder (hyperactivity, impulsivity and inattentiveness). These abnormalities were evident when comparing the behaviour of separate (inbred: ‘Hom’) wildtype and NK1R-/- mouse strains. Here, we investigated whether the inbreeding protocol could influence their phenotype by comparing the behaviour of these mice with that of wildtype (NK1R+/+) and NK1R-/- progeny of heterozygous parents (‘Het’, derived from the same inbred strains). First, we recorded the spontaneous motor activity of the two colonies/genotypes, over 7 days. This continuous monitoring also enabled us to investigate whether the diurnal rhythm in motor activity differs in the two colonies/genotypes. NK1R-/- mice from both colonies were hyperactive compared with their wildtypes and their diurnal rhythm was also disrupted. Next, we evaluated the performance of the four groups of mice in the 5-Choice Serial Reaction-Time Task (5-CSRTT). During training, NK1R-/- mice from both colonies expressed more impulsive and perseverative behaviour than their wildtypes. During testing, only NK1R-/- mice from the Hom colony were more impulsive than their wildtypes, but NK1R-/- mice from both colonies were more perseverative. There were no colony differences in inattentiveness. Moreover, a genotype difference in this measure depended on time of day. We conclude that the hyperactivity, perseveration and, possibly, inattentiveness of NK1R-/- mice is a direct consequence of a lack of functional NK1R. However, the greater impulsivity of NK1R-/- mice depended on an interaction between a functional deficit of NK1R and other (possibly environmental and/or epigenetic) factors. PMID:25558794

  5. Jupiter Eruptions

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover

    Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers.

    This visible-light image is from NASA's Hubble Space Telescope taken on May 11, 2007. It shows the turbulent pattern generated by the two plumes on the upper left part of Jupiter.

    Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena.

    According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vi gorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  6. Jupiter Eruptions

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover

    Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers.

    This visible-light image is from NASA's Hubble Space Telescope taken on May 11, 2007. It shows the turbulent pattern generated by the two plumes on the upper left part of Jupiter.

    Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena.

    According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vi gorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  7. Jupiter Wave

    NASA Image and Video Library

    2015-10-13

    Scientists spotted a rare wave in Jupiter North Equatorial Belt that had been seen there only once before in this false-color close-up from NASA Hubble Telescope. In Jupiter's North Equatorial Belt, scientists spotted a rare wave that had been seen there only once before. It is similar to a wave that sometimes occurs in Earth's atmosphere when cyclones are forming. This false-color close-up of Jupiter shows cyclones (arrows) and the wave (vertical lines). http://photojournal.jpl.nasa.gov/catalog/PIA19659

  8. Explaining linkages (and lack of) between riparian vegetation biodiversity and geomorphic complexity in restored streams of northern Sweden

    NASA Astrophysics Data System (ADS)

    Polvi, Lina; Maher Hasselquist, Eliza; Nilsson, Christer

    2014-05-01

    plots at three elevations above the low water stage (0, 40, and 80 cm) along five transects; additionally, we determined which species were present within the entire riparian zone (60 m long reach, up to 80 cm elevation). Three metrics of biodiversity were calculated on the plot level (richness, Shannon's diversity index, and evenness); only richness could be examined at the reach scale. There are significant relationships between riparian vegetation biodiversity and the overall complexity gradient at the medium elevation and, based on some metrics, at the low elevation. However, these relationships are not fully explanatory or always linear, explaining up to ~40% of the variability and often being logarithmic. We conclude that reach-scale restoration of increasing complexity in a catchment without significant land-use impacts can have positive effects on biodiversity. However, there are several limiting factors in addition to channel complexity that affect the recovery of riparian zones after restoration: the potential complexity of a reach based on large-scale controls, time since restoration—which is a disturbance in itself, buffer distance to timber harvesting, distance and connectivity to colonist sources, and upland species (e.g., spruce trees) that have managed to colonize when the riparian zone was separated from the channel.

  9. Jupiter Temperatures

    NASA Image and Video Library

    1997-09-29

    This is one of the highest resolution images ever recorded of Jupiter temperature field. It was obtained by NASA Galileo mission. This map, shown in the lower panel, indicates the forces powering Jovian winds.

  10. Jupiter's Magnetotail

    NASA Astrophysics Data System (ADS)

    Krupp, Norbert; Kronberg, Elena; Radioti, Aikaterini

    2015-01-01

    The spacecraft exploration of Jupiter and its environment has a history of approximately 40 years. Jupiter's magnetotail is highly dynamic and changes in the overall particles and field parameters occur on time scales of minutes up to several days. Jupiter is rotationally driven and the solar wind does not play the major role as at Earth. This chapter summarizes the current knowledge about particle and field observations from Jupiter's outer magnetodisc and magnetotail. The observed "energetic events" measured in energetic particles, plasma and radio waves, magnetic field north-south component, and auroral emissions occur throughout the magnetotail. They are most likely related to reconnection in the tail and appear quasi-periodically every few days, especially in the predawn sector of the magnetosphere.

  11. Approaching Jupiter

    NASA Image and Video Library

    2017-05-05

    This enhanced color view of Jupiter's south pole was created by citizen scientist Gabriel Fiset using data from the JunoCam instrument on NASA's Juno spacecraft. Oval storms dot the cloudscape. Approaching the pole, the organized turbulence of Jupiter's belts and zones transitions into clusters of unorganized filamentary structures, streams of air that resemble giant tangled strings. The image was taken on Dec. 11, 2016 at 9:44 a.m. PST (12:44 p.m. EST), from an altitude of about 32,400 miles (52,200 kilometers) above the planet's beautiful cloud tops. https://photojournal.jpl.nasa.gov/catalog/PIA21390

  12. Sharpening Up Jupiter

    NASA Astrophysics Data System (ADS)

    2008-10-01

    , MAD project manager Enrico Marchetti and Sébastien Tordo from the MAD team tracked two of Jupiter's largest moons, Europa and Io - one on each side of the planet - to provide a good correction across the full disc of the planet. "It was the most challenging observation we performed with MAD, because we had to track with high accuracy two moons moving at different speeds, while simultaneously chasing Jupiter," says Marchetti. With this unique series of images, the team found a major alteration in the brightness of the equatorial haze, which lies in a 16 000-kilometre wide belt over Jupiter's equator [2]. More sunlight reflecting off upper atmospheric haze means that the amount of haze has increased, or that it has moved up to higher altitudes. "The brightest portion had shifted south by more than 6000 kilometres," explains team member Mike Wong. This conclusion came after comparison with images taken in 2005 by Wong and colleague Imke de Pater using the Hubble Space Telescope. The Hubble images, taken at infrared wavelengths very close to those used for the VLT study, show more haze in the northern half of the bright Equatorial Zone, while the 2008 VLT images show a clear shift to the south. "The change we see in the haze could be related to big changes in cloud patterns associated with last year's planet-wide upheaval, but we need to look at more data to narrow down precisely when the changes occurred," declares Wong.

  13. Jupiter's Grand Attack

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin

    2017-06-01

    The statistics of extrasolar planetary systems indicate that the default mode of planetary formation generates planets with orbital periods shorter than 100 days, and masses substantially exceeding that of the Earth. When viewed in this context, the Solar System, which contains no planets interior to Mercury's 88-day orbit, is unusual. Extra-solar planetary detection surveys also suggest that planets with masses and periods broadly similar to Jupiter's are somewhat uncommon, with occurrence fraction of less than ~ 10%. In this talk, I will present calculations which show that a popular formation scenario for Jupiter and Saturn, in which Jupiter migrates inward from a > 5AU to a ˜ 1.5 AU and then reverses direction, can explain the low overall mass of the Solar System's terrestrial planets, as well as the absence of planets with a < 0.4 AU. Jupiter's inward migration entrained s > 10 - 100 km planetesimals into low- order mean-motion resonances, shepherding of order 10 Earth masses of this material into the a ˜ 1 AU region while exciting substantial orbital eccentricity (e ˜ 0.2 - 0.4). We argue that under these conditions, a collisional cascade will ensue, generating a planetesimal disk that would have flushed any preexisting short-period super-Earth-like planets into the Sun. In this scenario, the Solar System's terrestrial planets formed from gas-starved mass-depleted debris that remained after the primary period of dynamical evolution.

  14. Jupiter's snowball

    NASA Astrophysics Data System (ADS)

    Friebele, Elaine

    Recent observations from NASA's Galileo spacecraft reveal that Callisto, one of Jupiter's sixteen moons, is like an undifferentiated “dirty snowball” that has no internal magnetic field or magnetosphere. The outermost of the four large moons discovered by Galileo may be enshrouded by a tenuous atmosphere, however. The new findings, reported in the latest issue of Nature, are surprising because earlier data from Galileo indicates that two of Jupiter's other Galilean moons—Ganymede and Io—have magnetic fields. John D. Anderson of the Jet Propulsion Laboratory in Pasadena, Calif., and colleagues presented gravimetric data showing that Callisto is composed of 40% compressed ice and 60% rock mixed with metal. The undifferentiated composition is consistent with the absence of a magnetic field, which was confirmed by Krishan Khurana of the University of California and his colleagues.

  15. Jupiter's radiation belts.

    NASA Technical Reports Server (NTRS)

    Brice, N.; Mcdonough, T. R.

    1973-01-01

    A model for the production and loss of energetic electrons in Jupiter's radiation belt is presented. It is postulated that the electrons originate in the solar wind and are diffused in toward the planet by perturbations which violate the particles' third adiabatic invariant. At large distances, magnetic perturbations, electric fields associated with magnetospheric convection, or interchange instabilities driven by thermal plasma gradients may drive the diffusion. Inside about 10 Jupiter radii, the diffusion is probably driven by electric fields associated with the upper atmosphere dynamo which is driven by neutral winds in the ionosphere. The diurnal component of the dynamo wind fields produces a dawn-dusk asymmetry in the decimetric radiation from the electrons in the belts, and the lack of obvious measured asymmetries in the decimetric radiation measurements provides estimates of upper limits for these Jovian ionospheric neutral winds.

  16. Lack of skeletal effect of soy isoflavones in intact growing, female rats may be explained by constant serum estrogenic activity despite reduced serum estradiol.

    PubMed

    Peterson, Catherine A; Kubas, Karen L; Hartman, Stephanie J; Rottinghaus, George E; Taylor, Julia A; Welshons, Wade V

    2008-01-01

    Scarce data exist on the effects of soy isoflavones (IF) on bone during peripuberty, a known 'window of opportunity' for bone consolidation. Our aim was to determine the skeletal, reproductive, and serum estradiol (E(2))/estrogenic activity response of consuming naturally-occurring soy protein-associated IF during peripuberty. Weanling (approximately 3 weeks old), female rats were placed on one of four nutritionally-complete dietary regimens in which protein (200 g/kg diet) was provided as casein or soy protein isolates containing either 0.11 (Low IF), 2.16 (Med IF), or 3.95 (High IF) mg total aglycone isoflavones/g protein for 8 weeks, during which body weights and estrus cycling were recorded. Bone growth and density were unaffected by soy intake while the reproductive tissues showed a slight response (greater uterine weights of the Med and High IF groups). Despite suppression of E(2) concentrations in the High IF group, total circulating estrogenic activity was unaltered. Moreover, in the High IF group, E(2) was significantly depressed compared with bioassayable estrogenic activity, suggesting negative feedback inhibition of E(2) by the elevated circulating levels of IF. This suppression in E(2) with maintenance of total serum estrogenicity in the High IF group may explain the lack of effect observed in the skeletal tissues. (c) 2008 S. Karger AG, Basel.

  17. UV Studies of Jupiter's Aerosols and Hydrocarbons

    NASA Technical Reports Server (NTRS)

    Pryor, Wayne

    2004-01-01

    This project funded research related to our involvement in the Galileo Ultraviolet Spectrometer experiment. Pryor was a Co-I on that experiment, which recently ended when Galileo crashed into Jupiter's atmosphere. It also funded related research on HST observations of Jupiter's atmosphere, and Cassini observations of Jupiter's atmosphere, and ground-based studies of Jupiter's atmosphere using the facilities of McDonald Observatory. Specific activities related to this grant include study of UV spectra returned by Galileo UVS and Cassini UVIS, development of simple models to explain these spectra, participation in archiving activities for these data sets, travel to conferences, and publication of scientific papers. Highlights of our Jupiter research efforts include: 1.) evidence for heavy hydrocarbons in Jupiter's atmosphere (from HST) (Clarke et al. poster), that may be the source of Jupiter's stratospheric aerosols, 2.) detection of auroral flares in Jupiter's atmosphere from Galileo (Pryor et al., 2001). 3.) establishing a connection between coronal mass ejections and auroral outbursts (Gurnett et al., 2002), and 4) establishing a connection between short-term variations in Jupiter's auroral emissions and radio emissions (Pryor et al. presented at AGU in 2002, paper in preparation).

  18. Jupiter's Decametric Radio Emission and the Radiation Belts of Its Galilean Satellites.

    PubMed

    Burns, J A

    1968-03-01

    Many of the observed properties of Jupiter's decametric radiation may be explained by postulation that the inner Galilean satellites of Jupiter have magnetic properties that strongly distort Jupiter's magnetic field in the region of each satellite. Charged particles from Jupiter's radiation belts are trapped by these distorted fields and emit synchrotron radiation.

  19. Surfing Jupiter

    NASA Image and Video Library

    2017-05-25

    Waves of clouds at 37.8 degrees latitude dominate this three-dimensional Jovian cloudscape, courtesy of NASA's Juno spacecraft. JunoCam obtained this enhanced-color picture on May 19, 2017, at 5:50 UTC from an altitude of 5,500 miles (8,900 kilometers). Details as small as 4 miles (6 kilometers) across can be identified in this image. The small bright high clouds are about 16 miles (25 kilometers) across and in some areas appear to form "squall lines" (a narrow band of high winds and storms associated with a cold front). On Jupiter, clouds this high are almost certainly composed of water and/or ammonia ice. https://photojournal.jpl.nasa.gov/catalog/PIA21646

  20. Galileo's Telescopy and Jupiter's Tablet

    NASA Astrophysics Data System (ADS)

    Usher, P. D.

    2003-12-01

    A previous paper (BAAS 33:4, 1363, 2001) reported on the dramatic scene in Shakespeare's Cymbeline that features the descent of the deity Jupiter. The paper suggested that the four ghosts circling the sleeping Posthumus denote the four Galilean moons of Jupiter. The god Jupiter commands the ghosts to lay a tablet upon the prone Posthumus, but says that its value should not be overestimated. When Posthumus wakens he notices the tablet, which he calls a "book." Not only has the deity's "tablet" become the earthling's "book," but it appears that the book has covers which Posthumus evidently recognizes because without even opening the book he ascribes two further properties to it: rarity, and the very property that Jupiter had earlier attributed, viz. that one must not read too much into it. The mystery deepens when the Jovian gift undergoes a second metamorphosis, to "label." With the help of the OED, the potentially disparate terms "tablet," "book," and "label," may be explained by terms appropriate either to supernatural or worldly beings. "Tablet" may recognize the Mosaic artifact, whereas "book" and "label" are probably mundane references to Galileo's Sidereus Nuncius which appeared shortly before Cymbeline. The message of the Olympian god indicates therefore that the book is unique even as its contents have limited value. The first property celebrates the fact that Galileo's book is the first of its kind, and the second advises that all results except the discovery of Jupiter's moons have been reported earlier, in Hamlet.

  1. Can social capital help explain enrolment (or lack thereof) in community-based health insurance? Results of an exploratory mixed methods study from Senegal.

    PubMed

    Mladovsky, Philipa; Soors, Werner; Ndiaye, Pascal; Ndiaye, Alfred; Criel, Bart

    2014-01-01

    CBHI has achieved low population coverage in West Africa and elsewhere. Studies which seek to explain this point to inequitable enrolment, adverse selection, lack of trust in scheme management and information and low quality of health care. Interventions to address these problems have been proposed yet enrolment rates remain low. This exploratory study proposes that an under-researched determinant of CBHI enrolment is social capital. Fieldwork comprising a household survey and qualitative interviews was conducted in Senegal in 2009. Levels of bonding and bridging social capital among 720 members and non-members of CBHI across three case study schemes are compared. The results of the logistic regression suggest that, controlling for age and gender, in all three case studies members were significantly more likely than non-members to be enrolled in another community association, to have borrowed money from sources other than friends and relatives and to report having control over all community decisions affecting daily life. In two case studies, having privileged social relationships was also positively correlated with enrolment. After controlling for additional socioeconomic and health variables, the results for borrowing money remained significant. Additionally, in two case studies, reporting having control over community decisions and believing that the community would cooperate in an emergency were significantly positively correlated with enrolment. The results suggest that CBHI members had greater bridging social capital which provided them with solidarity, risk pooling, financial protection and financial credit. Qualitative interviews with 109 individuals selected from the household survey confirm this interpretation. The results ostensibly suggest that CBHI schemes should build on bridging social capital to increase coverage, for example by enrolling households through community associations. However, this may be unadvisable from an equity perspective. It is

  2. Cylindrical Projection of Jupiter

    NASA Image and Video Library

    1996-01-29

    This computer generated map of Jupiter was made from 10 color images of Jupiter taken Feb. 1, 1979, by NASA Voyager 1, during a single, 10 hour rotation of the planet. http://photojournal.jpl.nasa.gov/catalog/PIA00011

  3. Jupiter Eye to Io

    NASA Image and Video Library

    2000-12-12

    This image taken by NASA Cassini spacecraft on Dec. 1, 2000, shows details of Jupiter Great Red Spot and other features that were not visible in images taken earlier, when Cassini was farther from Jupiter.

  4. Ulysses at Jupiter

    NASA Image and Video Library

    2004-02-05

    An artist impression of Ulysses spacecraft at Jupiter. Ulysses used Jupiter powerful gravity to hurl it out of the Plane of the Ecliptic where most planets and satellites orbit so it could study the polar regions of the Sun.

  5. Voyager 2 Jupiter encounter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    A NASA News Release is presented which contains the following: (1) general release; (2) two views of Voyager 2 flight past Jupiter; (3) Voyager mission summary; (4) Voyager 1 science results; (5) Jupiter science objectives; (6) Jupiter the planet and its satellites; (7) Voyager experiments; (8) planet comparison; (9) a list of Voyager science investigators and (10) the Voyager team.

  6. Explaining Academic-Track Boys' Underachievement in Language Grades: Not a Lack of Aptitude but Students' Motivational Beliefs and Parents' Perceptions?

    ERIC Educational Resources Information Center

    Heyder, Anke; Kessels, Ursula; Steinmayr, Ricarda

    2017-01-01

    Background: Boys earn lower grades in languages than girls. The expectancy-value model by Eccles" et al." (1983, "A series of books in psychology. Achievement and achievement motives. Psychological and sociological approaches," W.H. Freeman, San Francisco, CA, 76) is a comprehensive theoretical model for explaining gender…

  7. Explaining the Modality Effect in Multimedia Learning: Is It Due to a Lack of Temporal Contiguity with Written Text and Pictures?

    ERIC Educational Resources Information Center

    Schuler, Anne; Scheiter, Katharina; Rummer, Ralf; Gerjets, Peter

    2012-01-01

    The study examined whether the modality effect is caused by either high visuo-spatial load or a lack of temporal contiguity when processing written text and pictures. Students (N = 147) viewed pictures on the development of tornados, which were accompanied by either spoken or written explanations presented simultaneously with, before, or after the…

  8. Explaining the Modality Effect in Multimedia Learning: Is It Due to a Lack of Temporal Contiguity with Written Text and Pictures?

    ERIC Educational Resources Information Center

    Schuler, Anne; Scheiter, Katharina; Rummer, Ralf; Gerjets, Peter

    2012-01-01

    The study examined whether the modality effect is caused by either high visuo-spatial load or a lack of temporal contiguity when processing written text and pictures. Students (N = 147) viewed pictures on the development of tornados, which were accompanied by either spoken or written explanations presented simultaneously with, before, or after the…

  9. Hot Jupiter Radii: A Turbulent History

    NASA Astrophysics Data System (ADS)

    Youdin, Andrew N.; Komacek, Thaddeus D.

    2014-11-01

    Many hot Jupiters, i.e. giant exoplanets with short orbital periods, are bloated, with radii that greatly exceed those of colder gas giants. In models that neglect atmospheric motion, the enhanced irradiation of hot Jupiters is insufficient to explain their large radii. However uneven surface irradiation drives atmospheric circulation. These atmospheric motions deposit heat at deeper layers than irradiation alone, and can explain their large radii. The specific dissipation mechanism for atmospheric circulation can involve a turbulent cascade and/or the driving of electric currents that undergo Ohmic dissipation. The “Mechanical Greenhouse” model (Youdin & Mitchell, 2010) showed that turbulence in hot Jupiter atmospheres does mechanical work against the stable stratification of upper radiative zones, thereby driving a heat flux deeper into the interior. This poster will describe the first efforts to include this turbulent heat flux in planetary structure models. The goal is to understand the effects of turbulent mixing on hot Jupiter radius evolution. To perform these calculations we modify the publicly available stellar structure code MESA. We show how the effects of turbulence can be included in MESA — and understood physically — as an effective dissipation profile. We compare the radius evolution of hot Jupiters for different dissipation prescriptions, including our turbulent mixing model and others from the literature. We find that turbulent mixing is an energetically efficient way to explain the bloated radii of hot Jupiters.

  10. Explaining academic-track boys' underachievement in language grades: Not a lack of aptitude but students' motivational beliefs and parents' perceptions?

    PubMed

    Heyder, Anke; Kessels, Ursula; Steinmayr, Ricarda

    2017-06-01

    Boys earn lower grades in languages than girls. The expectancy-value model by Eccles et al. (, A series of books in psychology. Achievement and achievement motives. Psychological and sociological approaches, W.H. Freeman, San Francisco, CA, 76) is a comprehensive theoretical model for explaining gender differences in educational outcomes. In the past, most studies have focused on girls' disadvantage in math and science and on the role of the students' motivational beliefs. We aimed to explain boys' lower language grades by applying the expectancy-value model while taking into account students' motivational beliefs as well as their aptitude, prior achievement, and socializers' beliefs. In addition, we aimed at exploring the incremental contribution of each potential mediator. Five hundred and twenty German students (age M = 17 years; 58% female) and 374 parents (age M = 47 years). Student-reported ability self-concept (ASC) and task values, parents' perceptions of students' ability, students' prior achievement as reported by schools, and students' verbal intelligence test scores were all tested as mediators of the effect of gender on grades in German while controlling for parents' socioeconomic status. Single-mediator models and a multiple-mediator model were estimated using structural equation modelling. All variables proved to be relevant for explaining boys' underachievement in language grades. Whereas students' ASC, task values, prior achievement, and parents' perceptions mediated the gender effect, verbal intelligence was identified as a suppressor variable increasing the gender effect. Our results challenge the stereotypic belief that boys' lower grades are due to lower verbal aptitude. Rather, students' motivational beliefs and parents' perceptions seem critical factors. Implications for both future research and practice are discussed. © 2017 The British Psychological Society.

  11. Allocation of limited reserves to a clutch: A model explaining the lack of a relationship between clutch size and egg size

    USGS Publications Warehouse

    Flint, Paul L.; Grand, James B.; Sedinger, James S.

    1996-01-01

    Lack (1967, 1968) proposed that clutch size in waterfowl is limited by the nutrients available to females when producing eggs. He suggested that if nutrients available for clutch formation are limited, then species producing small eggs would, on average, lay more eggs than species with large eggs. Rohwer (1988) argues that this model should also apply within species. Thus, the nutrition-limitation hypothesis predicts a tradeoff among females between clutch size and egg size (Rohwer 1988). Field studies of single species consistently have failed to detect a negative relationship between clutch size and egg size (Rohwer 1988, Lessells et al. 1992, Rohwer and Eisenhauer 1989, Flint and Sedinger 1992, Flint and Grand 1996). The absence of such a relationship within species has been regarded as evidence against the hypothesis that nutrient availability limits clutch size (Rohwer 1988, 1991, 1992; Rohwer and Eisenhauer 1989).

  12. Puzzling Lack of Temperature Dependence of the PuO2 Magnetic Susceptibility Explained According to Ab Initio Wave Function Calculations.

    PubMed

    Gendron, Frédéric; Autschbach, Jochen

    2017-02-02

    The electronic structure and the magnetic properties of solid PuO2 are investigated by wave function theory calculations, using a relativistic complete active space (CAS) approach including spin-orbit coupling. The experimental magnetic susceptibility is well reproduced by calculations for an embedded PuO8(12-) cluster model. The calculations indicate that the surprising lack of temperature dependence of the magnetic susceptibility χ of solid PuO2 can be rationalized based on the properties of a single Pu(4+) ion in the cubic ligand field of the surrounding oxygen ions. Below ∼300 K, the only populated state is the nonmagnetic ground state, leading to standard temperature-independent paramagnetism (TIP). Above 300 K, there is an almost perfect cancellation of temperature-dependent contributions to χ that depends delicately on the mixing of ion levels in the electronic states, their relative energies, and the magnetic coupling between them.

  13. Far infrared spectrophotometry of Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Erickson, E. F.; Goorvitch, D.; Simpson, J. P.; Strecker, D. W.

    1978-01-01

    Infrared spectral measurements of Mars, Jupiter, and Saturn were obtained from 100 to 470 kaysers and, by taking Mars as a calibration source, brightness temperatures of Jupiter and Saturn were determined with approximately 5 kayser resolution. Internal luminosities were determined from the data and are reported to be approximately 8 times 10 to the minus tenth power of the sun's luminosity for Jupiter and approximately 3.6 times 10 to the minus tenth power of the sun's luminosity for Saturn. Comparison of data with spectra predicted by models suggests the need for an opacity source in addition to gaseous hydrogen and ammonia to help explain Jupiter's observed spectrum in the vicinity of 250 kaysers.

  14. Ionosphere-Thermosphere Coupling in Jupiter's Low Latitudes

    NASA Astrophysics Data System (ADS)

    Stallard, T.; Melin, H.; Johnson, R.; O'Donoghue, J.; Moore, L.; Miller, S.; Tao, C.; Achilleos, N. A.; Smith, C.; Ray, L. C.; Yates, J. N.

    2015-12-01

    One of the leading problems in our understanding of Jupiter's atmosphere, known colloquially as the 'energy crisis', is that the upper atmosphere has global temperatures far in excess of that predicted by solar heating. Unlike the Earth, solar heating has only a small effect on the thermosphere, varying little in temperature with local time, and with equatorial neutrals co-rotating with the planet due to meridional advection. Within the auroral region, ionosphere-thermosphere coupling produces strong flows and results in huge Joule Heating from auroral currents. In this region, the temperature excess can be explained, but Jupiter's fast rotation means that Coriolis forces prevent energy in the poles from transferring equatorward, so there remains no explanation of why low latitudes are overheated by a factor of 3-5 over that predicted by solar heating alone.Despite this anomaly, although the past twenty years has seen a wealth of new data and results in Jupiter's auroral region, studies of the equatorial region have been somewhat limited. This lack of investigation comes partly from the apparent uniform nature of the equatorial region, and partly from the difficulty in observing this region. It is only in the past three years that observers begun to re-examine this region, revealing evidence of complex interactions between the thermosphere and ionosphere, including what appears to be thermospheric weather patterns at a fixed planetary longitudes, stable over two decades; perhaps caused by continuous flows from the auroral region. Here, we introduce our recent research, in order to compare and contrast what has been observed at Jupiter with the more well understood interactions between Earth's ionosphere and thermosphere. We hope that this will open a discussion between the communities that will improve our understanding of the underlying physical processes, as they occur at both planets.

  15. Polar Lightning on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Images taken by the New Horizons Long-Range Reconnaissance Imager (LORRI) of Jupiter's night side showed lightning strikes. Each 'strike' is probably the cumulative brightness of multiple strikes. This is the first lightning seen at high latitudes on Jupiter; it demonstrates that convection is not confined to lower latitudes, implying an internal driving heat source. Their power is consistent with previous lightning measurements at Jupiter's lower latitudes, equivalent to extremely bright terrestrial 'super bolts.'

  16. Ammonia Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Ammonia Ice Clouds on Jupiter

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds (appearing as bright blue areas) as they form and disperse over five successive Jupiter 'days.' Scientists noted how the larger cloud travels along with a small, local deep hole.

  17. Ammonia Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of Ammonia Ice Clouds on Jupiter

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds (appearing as bright blue areas) as they form and disperse over five successive Jupiter 'days.' Scientists noted how the larger cloud travels along with a small, local deep hole.

  18. The formation of Jupiter's faint rings

    PubMed

    Burns; Showalter; Hamilton; Nicholson; de Pater I; Ockert-Bell; Thomas

    1999-05-14

    Observations by the Galileo spacecraft and the Keck telescope showed that Jupiter's outermost (gossamer) ring is actually two rings circumscribed by the orbits of the small satellites Amalthea and Thebe. The gossamer rings' unique morphology-especially the rectangular end profiles at the satellite's orbit and the enhanced intensities along the top and bottom edges of the rings-can be explained by collisional ejecta lost from the inclined satellites. The ejecta evolves inward under Poynting-Robertson drag. This mechanism may also explain the origin of Jupiter's main ring and suggests that faint rings may accompany all small inner satellites of the other jovian planets.

  19. Jupiter System Observer

    NASA Technical Reports Server (NTRS)

    Senske, Dave; Kwok, Johnny

    2008-01-01

    This slide presentation reviews the proposed mission for the Jupiter System Observer. The presentation also includes overviews of the mission timeline, science goals, and spacecraftspecifications for the satellite.

  20. Jupiter Rocket Engine

    NASA Technical Reports Server (NTRS)

    2004-01-01

    Engine for the Jupiter rocket. The Jupiter vehicle was a direct derivative of the Redstone. The Army Ballistic Missile Agency (ABMA) at Redstone Arsenal, Alabama, continued Jupiter development into a successful intermediate ballistic missile, even though the Department of Defense directed its operational development to the Air Force. ABMA maintained a role in Jupiter RD, including high-altitude launches that added to ABMA's understanding of rocket vehicle operations in the near-Earth space environment. It was knowledge that paid handsome dividends later.

  1. Warm Jupiters from Secular Planet-Planet Interactions

    NASA Astrophysics Data System (ADS)

    Petrovich, Cristobal; Tremaine, Scott

    2016-10-01

    Most warm Jupiters (gas-giant planets with 0.1 {{au}}≲ a≲ 1 au) have pericenter distances that are too large for significant orbital migration by tidal friction. We study the possibility that the warm Jupiters are undergoing secular eccentricity oscillations excited by an outer companion (a planet or star) in an eccentric and/or mutually inclined orbit. In this model, the warm Jupiters migrate periodically, in the high-eccentricity phase of the oscillation, but are typically observed at lower eccentricities. We show that in this model the steady-state eccentricity distribution of the warm Jupiters is approximately flat, which is consistent with the observed distribution if we restrict the sample to warm Jupiters with detected outer planetary companions. The eccentricity distribution of warm Jupiters without companions exhibits a peak at e≲ 0.2 that must be explained by a different formation mechanism. Based on a population synthesis study, we find that high-eccentricity migration excited by an outer planetary companion (1) can account for ˜ 20 % of the warm Jupiters and most of the warm Jupiters with e≳ 0.4; and (2) can produce most of the observed population of hot Jupiters, with a semimajor axis distribution that matches the observations, but fails to account adequately for ˜ 60 % of hot Jupiters with projected obliquities ≲ 20^\\circ . Thus ˜ 20 % of the warm Jupiters and ˜ 60 % of the hot Jupiters can be produced by high-eccentricity migration. We also provide predictions for the expected mutual inclinations and spin-orbit angles of the planetary systems with hot and warm Jupiters produced by high-eccentricity migration.

  2. Voyage to Jupiter.

    ERIC Educational Resources Information Center

    Morrison, David; Samz, Jane

    This publication illustrates the features of Jupiter and its family of satellites pictured by the Pioneer and the Voyager missions. Chapters included are: (1) "The Jovian System" (describing the history of astronomy); (2) "Pioneers to Jupiter" (outlining the Pioneer Mission); (3) "The Voyager Mission"; (4)…

  3. Speeding Towards Jupiter Pole

    NASA Image and Video Library

    2016-08-27

    Jupiter north polar region is coming into view as NASA Juno spacecraft approaches the giant planet. This view of Jupiter was taken on August 27, when Juno was 437,000 miles 703,000 kilometers away. http://photojournal.jpl.nasa.gov/catalog/PIA20895

  4. Jupiter Great Red Spot

    NASA Image and Video Library

    1997-09-07

    This view of Jupiter Great Red Spot is a mosaic of two images taken by NASA Galileo spacecraft. The Great Red Spot is a storm in Jupiter atmosphere and is at least 300 years-old. The image was taken on June 26, 1996. http://photojournal.jpl.nasa.gov/catalog/PIA00296

  5. Jupiter System Observer

    NASA Technical Reports Server (NTRS)

    Senske, Dave; Prockter, Louise

    2008-01-01

    This slide presentation reviews the scientific philosophy that is guiding the planning behind the Jupiter System Observer (JSO). The JSO would be a long-term platform for studying Jupiter and the complete Jovian system. The goal is to advance the understanding of the fundamental processes of planetary systems, their formation and evolution.

  6. Jupiter System Observer

    NASA Technical Reports Server (NTRS)

    Senske, Dave; Prockter, Louise

    2008-01-01

    This slide presentation reviews the scientific philosophy that is guiding the planning behind the Jupiter System Observer (JSO). The JSO would be a long-term platform for studying Jupiter and the complete Jovian system. The goal is to advance the understanding of the fundamental processes of planetary systems, their formation and evolution.

  7. Radiation belts of jupiter.

    PubMed

    Fillius, R W; McIlwain, C E

    1974-01-25

    Pioneer 10 counted relativistic electrons throughout the magnetosphere of Jupiter, with the greatest fluxes being inside 20 Jupiter radii. The peak flux of electrons with energy greater than 50 million electron volts was 1.3 x 10(7) per square centimeter per second at the innermost penetration of the radiation belts.

  8. Jupiter: its captured satellites.

    PubMed

    Bailey, J M

    1971-08-27

    Because of the small size and irregular orbits of the seven outer satellites of Jupiter, it is often assumed that they were derived by capture. The conditions whereby Jupiter can capture satellites have therefore been examined. Relationships derived on the basis of the three-body problem for planets in elliptical orbits enable the dimensions of the capture orbits around Jupiter to be calculated. It is found that Jupiter may capture satellites through the inner Lagrangian point when at perihelion or at aphelion. Captures at perihelion should give rise to satellites in direct orbits of 11.48 x 10(6) kilometers and capture at aphelion to retrograde orbits of 21.7 x 10(6) kilometers. The correspondence with the seven outer satellites suggests that Jupiter VI, VIl, and X in direct orbits at 11.47, 11.74, and 11.85 x 10(6) kilometers were captured at Jupiter perihelion, whereas Jupiter VIII, IX, XI, and XII in retrograde orbits of 23.5, 23.7, 22.5, and 21.2 x 10(6) kilometers were captured when Jupiter was at aphelion. Examination of the precapture orbits indicates that the seven outer satellites were derived from the asteroid belt.

  9. Juno on Jupiter Doorstep

    NASA Image and Video Library

    2016-06-24

    NASA's Juno spacecraft obtained this color view on June 21, 2016, at a distance of 6.8 million miles (10.9 million kilometers) from Jupiter. As Juno makes its initial approach, the giant planet's four largest moons -- Io, Europa, Ganymede and Callisto -- are visible, and the alternating light and dark bands of the planet's clouds are just beginning to come into view. Juno is approaching over Jupiter's north pole, affording the spacecraft a unique perspective on the Jupiter system. Previous missions that imaged Jupiter on approach saw the system from much lower latitudes, closer to the planet's equator. The scene was captured by the mission's imaging camera, called JunoCam, which is designed to acquire high resolution views of features in Jupiter's atmosphere from very close to the planet. http://photojournal.jpl.nasa.gov/catalog/PIA20701

  10. Jupiter's Hot, Mushy Moon

    NASA Technical Reports Server (NTRS)

    Taylor, G. Jeffrey

    2003-01-01

    Jupiter's moon Io is the most volcanically active body in the Solar System. Observations by instruments on the Galileo spacecraft and on telescopes atop Mauna Kea in Hawai'i indicate that lava flows on Io are surprisingly hot, over 1200 oC and possibly as much as 1300 oC; a few areas might have lava flows as hot as 1500 oC. Such high temperatures imply that the lava flows are composed of rock that formed by a very large amount of melting of Io's mantle. This has led Laszlo Keszthelyi and Alfred S. McEwen of the University of Arizona and me to reawaken an old hypothesis that suggests that the interior of Io is a partially-molten mush of crystals and magma. The idea, which had fallen out of favor for a decade or two, explains high-temperature hot spots, mountains, calderas, and volcanic plains on Io. If correct, Io gives us an opportunity to study processes that operate in huge, global magma systems, which scientists believe were important during the early history of the Moon and Earth, and possibly other planetary bodies as well. Though far from proven, the idea that Io has a ocean of mushy magma beneath its crust can be tested with measurements by future spacecraft.

  11. The Capture of Jupiter Trojans

    NASA Astrophysics Data System (ADS)

    Morbidelli, A.; Nesvorny, D.; Vokrouhlicky, D.

    2013-09-01

    The origin of Jupiter Trojans remained mysterious for decades. Particularly, it was difficult to explain the excitation of the inclinations of the Trojan population [1]. In 2005, Morbidelli et al. [2] proposed a scenario of capture from the trans-Neptunian disk, in the framework of the so-called "Nice model" [3,4]. This scenario explained in a natural way the observed orbital distribution of Trojans. The Nice model, however, evolved in the years, in order to satisfy an increasingly large number of constraints. It now appears that the dynamical evolution of the giant planets was different from that envisioned in [2]. Here, we assess again the process of capture of Trojans within this new evolution. We show that (6-8)×10 - 7 of the original trans-Neptunian planetesimals are captured in the Trojan region, with an orbital distribution consistent with the one observed. Relative to [2], the new capture mechanism has the potential of explaining the asymmetry between the L4 and L5 populations. Moreover, the resulting population of Trojans is consistent with that of the Irregular Satellites of Jupiter, which are captured in the same process; a few bodies from the main asteroid belt could also be captured in the Trojan cloud.

  12. Planetary geometry handbook: Jupiter positional data, 1985 - 2020, volume 4

    NASA Technical Reports Server (NTRS)

    Sergeyevsky, A. B.; Snyder, G. C.; Paulson, B. L.; Cunniff, R. A.

    1983-01-01

    Graphical data necessary for the analysis of planetary exploration missions to Jupiter are presented. Positional and geometric information spanning the time period from 1985 through 2020 is provided. The data and their usage are explained.

  13. The Edge of Jupiter

    NASA Image and Video Library

    2017-04-19

    This enhanced color Jupiter image, taken by the JunoCam imager on NASA's Juno spacecraft, showcases several interesting features on the apparent edge (limb) of the planet. Prior to Juno's fifth flyby over Jupiter's mysterious cloud tops, members of the public voted on which targets JunoCam should image. This picture captures not only a fascinating variety of textures in Jupiter's atmosphere, it also features three specific points of interest: "String of Pearls," "Between the Pearls," and "An Interesting Band Point." Also visible is what's known as the STB Spectre, a feature in Jupiter's South Temperate Belt where multiple atmospheric conditions appear to collide. JunoCam images of Jupiter sometimes appear to have an odd shape. This is because the Juno spacecraft is so close to Jupiter that it cannot capture the entire illuminated area in one image -- the sides get cut off. Juno acquired this image on March 27, 2017, at 2:12 a.m. PDT (5:12 a.m. EDT), as the spacecraft performed a close flyby of Jupiter. When the image was taken, the spacecraft was about 12,400 miles (20,000 kilometers) from the planet. This enhanced color image was created by citizen scientist Bjorn Jonsson. https://photojournal.jpl.nasa.gov/catalog/PIA21389

  14. Jupiter's Northern Lights

    NASA Image and Video Library

    2017-09-06

    This is a reconstructed view of Jupiter's northern lights through the filters of Juno's Ultraviolet Imaging Spectrometer (UVS) instrument on Dec. 11, 2016, as the Juno spacecraft approached Jupiter, passed over its poles, and plunged towards the equator. Such measurements present a real challenge for the spacecraft's science instruments: Juno flies over Jupiter's poles at 30 miles (50 kilometers) per second -- more than 100,000 miles per hour -- speeding past auroral forms in a matter of seconds. https://photojournal.jpl.nasa.gov/catalog/PIA21938

  15. Jupiter Environment Tool

    NASA Technical Reports Server (NTRS)

    Sturm, Erick J.; Monahue, Kenneth M.; Biehl, James P.; Kokorowski, Michael; Ngalande, Cedrick,; Boedeker, Jordan

    2012-01-01

    The Jupiter Environment Tool (JET) is a custom UI plug-in for STK that provides an interface to Jupiter environment models for visualization and analysis. Users can visualize the different magnetic field models of Jupiter through various rendering methods, which are fully integrated within STK s 3D Window. This allows users to take snapshots and make animations of their scenarios with magnetic field visualizations. Analytical data can be accessed in the form of custom vectors. Given these custom vectors, users have access to magnetic field data in custom reports, graphs, access constraints, coverage analysis, and anywhere else vectors are used within STK.

  16. Moons around Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons Long Range Reconnaissance Imager (LORRI) took this photo of Jupiter at 20:42:01 UTC on January 9, 2007, when the spacecraft was 80 million kilometers (49.6 million miles) from the giant planet. The volcanic moon Io is to the left of the planet; the shadow of the icy moon Ganymede moves across Jupiter's northern hemisphere.

    Ganymede's average orbit distance from Jupiter is about 1 million kilometers (620,000 miles); Io's is 422,000 kilometers (262,000 miles). Both Io and Ganymede are larger than Earth's moon; Ganymede is larger than the planet Mercury.

  17. What Determines the Presence of a Thermal Inversion in Hot Jupiters?

    NASA Astrophysics Data System (ADS)

    Beatty, Thomas G.; Madhusudhan, Nikku; Pogge, Richard W.; Tsiaras, Angelos; Gaudi, B. Scott; Chung, Sun Mi

    2017-01-01

    Stratospheric temperature inversions in the atmospheres of giant exoplanets, once expected to be fairly common in hot Jupiters, have proven to be extremely elusive. Even though many planets have day side temperatures above the TiO/VO condensation point, TiO/VO-driven thermal inversions seem to be rare. Recent observations, however, have given some of the first clear detections of thermal inversions in two very hot giant exoplanets' atmospheres. We report on observations of two additional systems in the same temperature range, which again suggest that the presence of an inversion is not solely driven by atmospheric temperature. Our hypothesis for why this is so would explain the lack of an inversion in our two targets, as well as in cooler hot Jupiters, and would support some theoretical predictions for the processes governing TiO/VO inversions.

  18. Jupiter with Io Crossing

    NASA Image and Video Library

    1996-09-26

    million kilometers). The satellite's shadow can be seen falling on the face of Jupiter at left. Io is traveling from left to right in its one-and-three-quarter-day orbit around Jupiter. Even from this great distance the image of Io shows dark poles and a bright equatorial region. Voyager will make its closest approach to Jupiter -- 174,000 miles (280,000 kilometer) -- on March 5. It will then continue to Saturn in November 1980, Meanwhile Voyager 2, a sister spacecraft, will fly past Jupiter July 9, 1979, and reach Saturn in August 1981. This color image was taken through orange, green and blue filters. http://photojournal.jpl.nasa.gov/catalog/PIA00455

  19. Jupiter Stratospheric Haze Comparison

    NASA Image and Video Library

    1997-12-18

    These two views of Jupiter obtained by NASA Galileo spacecraft show evidence of strikingly different stratospheric hazes between the polar regions and low or mid latitudes. The Great Red Spot shows in one mosaic taken on June 26, 1996.

  20. Juno: Launching to Jupiter

    NASA Image and Video Library

    The Juno spacecraft will look deep beneath Jupiter's swirling curtains of clouds to decipher the planet's structure and history during a mission that will begin with a 5-year flight through deep sp...

  1. Jupiter Ring, With Orion

    NASA Image and Video Library

    2017-05-25

    As NASA's Juno spacecraft flew through the narrow gap between Jupiter's radiation belts and the planet during its first science flyby, Perijove 1, on August 27, 2016, the Stellar Reference Unit (SRU-1) star camera collected the first image of Jupiter's ring taken from the inside looking out. The bright bands in the center of the image are the main ring of Jupiter's ring system. While taking the ring image, the SRU was viewing the constellation Orion. The bright star above the main ring is Betelgeuse, and Orion's belt can be seen in the lower right. Juno's Radiation Monitoring Investigation actively retrieves and analyzes the noise signatures from penetrating radiation in the images of the spacecraft's star cameras and science instruments at Jupiter. https://photojournal.jpl.nasa.gov/catalog/PIA21644

  2. Jupiter Shakes it Off

    NASA Image and Video Library

    2012-10-17

    Jupiter has been suffering more impacts over the last four years than ever previously observed, including this meteoroid impact on Sept. 10, 2012. Right-hand image is an infrared image NASA Infrared Telescope Facility on Mauna Kea, Hawaii.

  3. Jupiter Scar in Infrared

    NASA Image and Video Library

    2011-01-26

    These infrared images obtained from NASA Infrared Telescope Facility in Mauna Kea, Hawaii, show before and aftereffects from particle debris in Jupiter atmosphere after an object hurtled into the atmosphere on July 19, 2009.

  4. Ammonia Clouds on Jupiter

    NASA Image and Video Library

    2007-10-09

    In this movie, put together from false-color images taken by the New Horizons Ralph instrument as the spacecraft flew past Jupiter in early 2007, show ammonia clouds appearing as bright blue areas as they form and disperse.

  5. Aurora Borealis on Jupiter

    NASA Image and Video Library

    1997-12-18

    This image, taken by NASA Galileo spacecraft, shows the darkside of Jupiter, the part not illuminated by sunlight. The curved line crossing from the lower left to the upper right is the auroral arc on the horizon.

  6. Acetylene around Jupiter Poles

    NASA Image and Video Library

    2010-12-29

    This graphic shows the distribution of the organic molecule acetylene at the north and south poles of Jupiter, based on data obtained by NASA Cassini spacecraft in early January 2001. Movie is available at the Photojournal.

  7. The Jupiter program

    SciTech Connect

    Ramirez, J.J.

    1995-08-01

    Jupiter is a Sandia initiative to develop the next generation of fast Z-pinch drivers for applications to high energy density physics, inertial confinement fusion, and radiation effects simulation. Jupiter will also provide unique capabilities for science research in a broad spectrum of areas involving ultra high magnetic fields, hot/dense plasmas, x-ray physics, intense neutron sources, etc. The program is based on the premise that a single facility using magnetically driven implosions can meet the needs in these multiple program areas. Jupiter requires a 450-500 TW, 8-10 MV, {approx} 100 ns pulsed power generator to impart - 15 MJ kinetic energy to an imploding plasma load. The baseline concept uses a highly modular, robust architecture with demonstrated performance reliability. The design also has the flexibility to drive longer implosion times. This paper describes the Jupiter accelerator concept, and the research underway to establish the technological readiness to proceed with construction of the facility.

  8. Cassini Jupiter Portrait

    NASA Image and Video Library

    2003-11-13

    This true color mosaic of Jupiter was constructed from images taken by the narrow angle camera onboard NASA Cassini spacecraft, during its closest approach to the giant planet and is its most detailed portrait.

  9. 95 Minutes Over Jupiter

    NASA Image and Video Library

    2017-09-28

    This sequence of color-enhanced images shows how quickly the viewing geometry changes for NASA's Juno spacecraft as it swoops by Jupiter. The images were obtained by JunoCam. Once every 53 days, Juno swings close to Jupiter, speeding over its clouds. In just two hours, the spacecraft travels from a perch over Jupiter's north pole through its closest approach (perijove), then passes over the south pole on its way back out. This sequence shows 11 color-enhanced images from Perijove 8 (Sept. 1, 2017) with the south pole on the left (11th image in the sequence) and the north pole on the right (first image in the sequence). The first image on the right shows a half-lit globe of Jupiter, with the north pole approximately at the upper center of the image close to the terminator -- the dividing line between night and day. As the spacecraft gets closer to Jupiter, the horizon moves in and the range of visible latitudes shrinks. The second and third images in this sequence show the north polar region rotating away from the spacecraft's field of view while the first of Jupiter's lighter-colored bands comes into view. The fourth through the eighth images display a blue-colored vortex in the mid-southern latitudes near Points of Interest "Collision of Colours," "Sharp Edge," "Caltech, by Halka," and "Structure01." The Points of Interest are locations in Jupiter's atmosphere that were identified and named by members of the general public. Additionally, a darker, dynamic band can be seen just south of the vortex. In the ninth and tenth images, the south polar region rotates into view. The final image on the left displays Jupiter's south pole in the center. From the start of this sequence of images to the end, roughly 1 hour and 35 minutes elapsed. https://photojournal.jpl.nasa.gov/catalog/PIA21967

  10. Jupiter Eye to Io

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This image taken by NASA's Cassini spacecraft on Dec. 1, 2000, shows details of Jupiter's Great Red Spot and other features that were not visible in images taken earlier, when Cassini was farther from Jupiter.

    The picture is a color composite, with enhanced contrast, taken from a distance of 28.6 million kilometers (17.8 million miles). It has a resolution of 170 kilometers (106 miles) per pixel. Jupiter's closest large moon, Io, is visible at left.

    The edges of the Red Spot are cloudier with ammonia haze than the spot's center is. The filamentary structure in the center appears to spiral outward toward the edge. NASA's Galileo spacecraft has previously observed the outer edges of the Red Spot to be rotating rapidly counterclockwise, while the inner portion was rotating weakly in the opposite direction. Whether the same is true now will be answered as Cassini gets closer to Jupiter and interior cloud features become sharper. Cassini will make its closest approach to Jupiter, at a distance of about 10 million kilometers (6 million miles), on Dec. 30, 2000.

    The Red Spot region has changed in one notable way over the years: In images from NASA's Voyager and Galileo spacecraft, the area surrounding the Red Spot is dark, indicating relatively cloud-free conditions. Now, some bright white ammonia clouds have filled in the clearings. This appears to be part of a general brightening of Jupiter's cloud features during the past two decades.

    Jupiter has four large moons and an array of tiny ones. In this picture, Io is visible. The white and reddish colors on Io's surface are due to the presence of different sulfurous materials while the black areas are due to silicate rocks. Like the other large moons, Io always keeps the same hemisphere facing Jupiter, called the sub-Jupiter hemisphere. The opposite side, much of which we see here, is the anti-Jupiter hemisphere. Io has more than 100 active volcanoes spewing very hot lava and giant plumes of gas and dust. Its

  11. Jupiter internal structure: the effect of different equations of state

    NASA Astrophysics Data System (ADS)

    Miguel, Y.; Guillot, T.; Fayon, L.

    2016-12-01

    Context. Heavy elements, even though they are a smaller constituent, are crucial to understand the formation history of Jupiter. Interior models are used to determine the amount of heavy elements in the interior of Jupiter, but this range is still subject to degeneracies because of the uncertainties in the equations of state. Aims: Before Juno mission data arrive, we present optimized calculations for Jupiter that explore the effect of different model parameters on the determination of the core and the mass of heavy elements of Jupiter. We compare recently published equations of state. Methods: The interior model of Jupiter was calculated from the equations of hydrostatic equilibrium, mass, and energy conservation, and energy transport. The mass of the core and heavy elements was adjusted to match the observed radius and gravitational moments of Jupiter. Results: We show that the determination of the interior structure of Jupiter is tied to the estimation of its gravitational moments and the accuracy of equations of state of hydrogen, helium, and heavy elements. Locating the region where helium rain occurs and defining its timescale is important to determine the distribution of heavy elements and helium in the interior of Jupiter. We show that the differences found when modeling the interior of Jupiter with recent EOS are more likely due to differences in the internal energy and entropy calculation. The consequent changes in the thermal profile lead to different estimates of the mass of the core and heavy elements, which explains differences in recently published interior models of Jupiter. Conclusions: Our results help clarify the reasons for the differences found in interior models of Jupiter and will help interpreting upcoming Juno data. Full appendix tables 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/596/A114

  12. Hot Jupiters and Super-Earths

    NASA Astrophysics Data System (ADS)

    Mustill, A. J.; Davies, M. B.; Johansen, A.

    2015-10-01

    We explore the role of dynamics in shaping planetary system multiplicities, focussing on two particular problems. (1) We propose that the lack of close-in super-Earths in hot Jupiter systems is a signature of the migration history of the hot Jupiters and helps to discriminate between different mechanisms of migration. We present N-body simulations of dynamical migration scenarios where proto-hot Jupiters are excited to high eccentricities prior to tidal circularisation and orbital decay. We show that in this scenario, the eccentric giant planet typically destroys planets in the inner system, in agreement with the observed lack of close super-Earth companions to hot Jupiters. (2) We explore the role of the dynamics of outer systems in affecting the multiplicities of close-in systems such as those discovered by Kepler. We consider specifically the effects of planet-planet scattering and Kozai perturbations on an exterior giant planet on the architecture of the inner system, and evaluate the ability of such scenarios to reduce the inner system's multiplicity and contribute to the observed excess of single Kepler planets.

  13. News conference on Voyager-2-Jupiter encounter

    NASA Technical Reports Server (NTRS)

    1978-01-01

    The proceedings of a news conference on the Voyager 2 Jupiter project are presented. Topics include the instrumentation on the Voyager 2, Jupiter's atmosphere and magnetic field, the Jupiter moons, and the observations of lightning on Jupiter.

  14. TOWARD CHEMICAL CONSTRAINTS ON HOT JUPITER MIGRATION

    SciTech Connect

    Madhusudhan, Nikku; Amin, Mustafa A.; Kennedy, Grant M.

    2014-10-10

    The origin of hot Jupiters—gas giant exoplanets orbiting very close to their host stars—is a long-standing puzzle. Planet formation theories suggest that such planets are unlikely to have formed in situ but instead may have formed at large orbital separations beyond the snow line and migrated inward to their present orbits. Two competing hypotheses suggest that the planets migrated either through interaction with the protoplanetary disk during their formation, or by disk-free mechanisms such as gravitational interactions with a third body. Observations of eccentricities and spin-orbit misalignments of hot Jupiter systems have been unable to differentiate between the two hypotheses. In the present work, we suggest that chemical depletions in hot Jupiter atmospheres might be able to constrain their migration mechanisms. We find that sub-solar carbon and oxygen abundances in Jovian-mass hot Jupiters around Sun-like stars are hard to explain by disk migration. Instead, such abundances are more readily explained by giant planets forming at large orbital separations, either by core accretion or gravitational instability, and migrating to close-in orbits via disk-free mechanisms involving dynamical encounters. Such planets also contain solar or super-solar C/O ratios. On the contrary, hot Jupiters with super-solar O and C abundances can be explained by a variety of formation-migration pathways which, however, lead to solar or sub-solar C/O ratios. Current estimates of low oxygen abundances in hot Jupiter atmospheres may be indicative of disk-free migration mechanisms. We discuss open questions in this area which future studies will need to investigate.

  15. Full Jupiter Mosaic

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This image of Jupiter is produced from a 2x2 mosaic of photos taken by the New Horizons Long Range Reconnaissance Imager (LORRI), and assembled by the LORRI team at the Johns Hopkins University Applied Physics Laboratory. The telescopic camera snapped the images during a 3-minute, 35-second span on February 10, when the spacecraft was 29 million kilometers (18 million miles) from Jupiter. At this distance, Jupiter's diameter was 1,015 LORRI pixels -- nearly filling the imager's entire (1,024-by-1,024 pixel) field of view. Features as small as 290 kilometers (180 miles) are visible.

    Both the Great Red Spot and Little Red Spot are visible in the image, on the left and lower right, respectively. The apparent 'storm' on the planet's right limb is a section of the south tropical zone that has been detached from the region to its west (or left) by a 'disturbance' that scientists and amateur astronomers are watching closely.

    At the time LORRI took these images, New Horizons was 820 million kilometers (510 million miles) from home -- nearly 51/2 times the distance between the Sun and Earth. This is the last full-disk image of Jupiter LORRI will produce, since Jupiter is appearing larger as New Horizons draws closer, and the imager will start to focus on specific areas of the planet for higher-resolution studies.

  16. 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

  17. Physics of Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Hamilton, Douglas P.; Krueger, H.

    2007-10-01

    Thebe's gossamer ring, the outermost and faintest of Jupiter's rings, has an outward extension that we have previously argued is due to a shadow resonance (Hamilton 2003, DPS meeting #35, #11.09). A shadow resonance arises from the abrupt shutoff of photoelectric charging when a dust particle enters Jupiter's shadow which, in turn, affects the strength of the electromagnetic perturbation from the planet's intense magnetic field. The result is a coupled oscillation between a particle's orbital eccentricity and its semimajor axis. Ring material spreads outward from Thebe while maintaining its vertical thickness just as observed by Galileo imaging. In addition to cameras, the Galileo spacecraft was also equipped with dust and plasma detectors. The spacecraft made two passes through the ring and its dust detector found that 1) dust fluxes drop immediately interior to Thebe's orbit, 2) some grains have inclinations in excess of 20 degrees and 3) submicron particles are present in the Amalthea ring in much greater numbers than in the Thebe ring. These findings can all be explained in the context of our shadow resonance model: the inner boundary is a direct consequence of the conservation of the Electromagnetic Jacobi Constant, the high inclinations are forced by a vertical resonance, and the excess submicron particles are a consequence of the weakening of electromagnetic forces in the vicinity of synchronous orbit. In this talk, we will present the data sets as well as detailed numerical simulations that back up these claims.

  18. Jupiter Temperatures--Broad Latitude

    NASA Image and Video Library

    1997-09-23

    This is one of the highest resolution images ever recorded of Jupiter temperature field. It was obtained by NASA Galileo mission, with its Photopolarimeter-Radiometer PPR experiment, during the seventh of its 10 orbits around Jupiter to date.

  19. Polar Atmospheric Dynamics of Jupiter

    NASA Astrophysics Data System (ADS)

    Sayanagi, Kunio M.; Mitchell, J. L.; Heavens, N. G.

    2012-10-01

    We investigate the transition in Jupiter's atmospheric dynamic regime between mid-latitudes to polar regions. Spacecraft observations of Jupiter have identified three distinct dynamical regimes in the cloud-top winds. In the equatorial region, a fast, broad jetstream blows eastward where no vortices are found. In the mid-latitudes, many vortices exist between the numerous jetstreams that alternate in wind direction between eastward and westward. On Jupiter, vortices become increasingly prevalent with latitude; poleward of 65 degree N/S latitudes, the banded structure that characterizes the lower latitudes becomes indiscernible, and the flow acquires an increasingly turbulent appearance with little zonal organization - we identify this regime as polar turbulence. Saturn also has a very similarly organized atmosphere, except that it maintains zonally organized cloud bands up to the poles and lacks polar turbulence. The zonal structure of Saturn culminates in the southern hemisphere with a hurricane-like cyclonic vortex residing precisely at south pole. Here, we focus on the transition from the mixed jet-vortex regime in the mid-latitudes to the vortex-dominated polar-regime of Jupiter. Using an idealized shallow-water model in a beta-plane channel, we test the stability of various scenarios that range between a jet-dominated flow and vortical turbulence. Since we are simulating a zone on the sphere rather than the full circulation, we test the sensitivity of the dynamics to latitude by varying the model’s beta-plane parameters, namely, the background Coriolis parameter f0 and its gradient beta. In addition, as we employ a 1 1/2-layer shallow-water model, we also vary the layer thickness and the bottom-layer topography to mimic a steeply varying thermal stratification (i.e., a potential vorticity front) by exploiting the topographic beta effects. We use the EPIC model (Dowling et al. 1998) to perform our numerical experiments. Our study is supported by a NASA Outer

  20. Under Jupiter's Cloud Tops

    NASA Image and Video Library

    2017-05-25

    NASA's Juno spacecraft carries an instrument called the Microwave Radiometer, which examines Jupiter's atmosphere beneath the planet's cloud tops. This image shows the instrument's view of the outer part of Jupiter's atmosphere. Before Juno began using this instrument, scientists expected the atmosphere to be uniform at depths greater than 60 miles (100 kilometers). But with the Microwave Radiometer, scientists have discovered that the atmosphere has variations down to at least 220 miles (350 kilometers), as deep as the instrument can see. In the cut-out image to the right, orange signifies high ammonia abundance and blue signifies low ammonia abundance. Jupiter appears to have a band around its equator high in ammonia abundance, with a column shown in orange. This is contrary to scientists' expectations that ammonia would be uniformly mixed. https://photojournal.jpl.nasa.gov/catalog/PIA21642

  1. A PRELIMINARY JUPITER MODEL

    SciTech Connect

    Hubbard, W. B.; Militzer, B.

    2016-03-20

    In anticipation of new observational results for Jupiter's axial moment of inertia and gravitational zonal harmonic coefficients from the forthcoming Juno orbiter, we present a number of preliminary Jupiter interior models. We combine results from ab initio computer simulations of hydrogen–helium mixtures, including immiscibility calculations, with a new nonperturbative calculation of Jupiter's zonal harmonic coefficients, to derive a self-consistent model for the planet's external gravity and moment of inertia. We assume helium rain modified the interior temperature and composition profiles. Our calculation predicts zonal harmonic values to which measurements can be compared. Although some models fit the observed (pre-Juno) second- and fourth-order zonal harmonics to within their error bars, our preferred reference model predicts a fourth-order zonal harmonic whose absolute value lies above the pre-Juno error bars. This model has a dense core of about 12 Earth masses and a hydrogen–helium-rich envelope with approximately three times solar metallicity.

  2. Jupiter Swirling Pearl Storm

    NASA Image and Video Library

    2017-03-30

    This image, taken by the JunoCam imager on NASA's Juno spacecraft, highlights a swirling storm just south of one of the white oval storms on Jupiter. The image was taken on March 27, 2017, at 2:12 a.m. PDT (5:12 a.m. EDT), as the Juno spacecraft performed a close flyby of Jupiter. At the time the image was taken, the spacecraft was about 12,400 miles (20,000 kilometers) from the planet. Citizen scientist Jason Major enhanced the color and contrast in this image, turning the picture into a Jovian work of art. He then cropped it to focus our attention on this beautiful example of Jupiter's spinning storms. https://photojournal.jpl.nasa.gov/catalog/PIA21387

  3. Jupiter's Rings: Sharpest View

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons spacecraft took the best images of Jupiter's charcoal-black rings as it approached and then looked back at Jupiter. The top image was taken on approach, showing three well-defined lanes of gravel- to boulder-sized material composing the bulk of the rings, as well as lesser amounts of material between the rings. New Horizons snapped the lower image after it had passed Jupiter on February 28, 2007, and looked back in a direction toward the sun. The image is sharply focused, though it appears fuzzy due to the cloud of dust-sized particles enveloping the rings. The dust is brightly illuminated in the same way the dust on a dirty windshield lights up when you drive toward a 'low' sun. The narrow rings are confined in their orbits by small 'shepherding' moons.

  4. Jupiter - friend or foe?

    NASA Astrophysics Data System (ADS)

    Horner, J.; Jones, B. W.

    2007-08-01

    Throughout both popular science and academia, there is a pervasive belief that Jupiter has acted as a celestial shield, reducing the impact rate on the Earth, and making the planet a significantly more conducive site for the evolution and survival of life. This old idea has, however, undergone little detailed scrutiny. In the first of a series of studies aimed at a better understanding of this idea, we examine the variation in the impact rate on the Earth which results from bodies moving inwards from the Edgeworth- Kuiper belt as a function of the mass of a giant planet in Jupiter's orbit. The results are not entirely what would be expected under the "Jupiter Shield" paradigm.

  5. Jupiter's Bands of Clouds

    NASA Image and Video Library

    2017-06-22

    This enhanced-color image of Jupiter's bands of light and dark clouds was created by citizen scientists Gerald Eichstädt and Seán Doran using data from the JunoCam imager on NASA's Juno spacecraft. Three of the white oval storms known as the "String of Pearls" are visible near the top of the image. Each of the alternating light and dark atmospheric bands in this image is wider than Earth, and each rages around Jupiter at hundreds of miles (kilometers) per hour. The lighter areas are regions where gas is rising, and the darker bands are regions where gas is sinking. Juno acquired the image on May 19, 2017, at 11:30 a.m. PST (2:30 p.m. EST) from an altitude of about 20,800 miles (33,400 kilometers) above Jupiter's cloud tops. https://photojournal.jpl.nasa.gov/catalog/PIA21393

  6. Jupiter Polar Winds Movie

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Bands of eastward and westward winds on Jupiter appear as concentric rotating circles in this movie composed of Cassini spacecraft images that have been re-projected as if the viewer were looking down at Jupiter's north pole and the planet were flattened.

    The sequence covers 70 days, from October 1 to December 9, 2000. Cassini's narrow-angle camera captured the images of Jupiter's atmosphere in the near-infrared region of the spectrum.

    What is surprising in this view is the coherent nature of the high-latitude flows, despite the very chaotic, mottled and non-banded appearance of the planet's polar regions. This is the first extended movie sequence to show the coherence and longevity of winds near the pole and the features blown around the planet by them.

    There are thousands of spots, each an active storm similar to the size to the largest of storms on Earth. Large terrestrial storms usually last only a week before they dissolve and are replaced by other storms. But many of the Jovian storms seen here, while occasionally changing latitude or merging with each other, persist for the entire 70 days. Until now, the lifetime of the high-latitude features was unknown. Their longevity is a mystery of Jovian weather.

    Cassini collected images of Jupiter for months before and after it passed the planet on December 30, 2000. Six or more images of the planet in each of several spectral filters were taken at evenly spaced intervals over the course of Jupiter's 10-hour rotation period. The entire sequence was repeated generally every other Jupiter rotation, yielding views of every sector of the planet at least once every 20 hours.

    The images used for the movie shown here were taken every 20 hours through a filter centered at a wavelength of 756 nanometers, where there are almost no absorptions in the planet's atmosphere. The images covering each rotation were mosaiced together to form a cylindrical map extending from 75 degrees north to 75 degrees south in

  7. Jupiter's outer atmosphere.

    NASA Technical Reports Server (NTRS)

    Brice, N. M.

    1973-01-01

    The current state of the theory of Jupiter's outer atmosphere is briefly reviewed. The similarities and dissimilarities between the terrestrial and Jovian upper atmospheres are discussed, including the interaction of the solar wind with the planetary magnetic fields. Estimates of Jovian parameters are given, including magnetosphere and auroral zone sizes, ionospheric conductivity, energy inputs, and solar wind parameters at Jupiter. The influence of the large centrifugal force on the cold plasma distribution is considered. The Jovian Van Allen belt is attributed to solar wind particles diffused in toward the planet by dynamo electric fields from ionospheric neutral winds, and the consequences of this theory are indicated.

  8. The planet Jupiter (1970)

    NASA Technical Reports Server (NTRS)

    Divine, N.

    1971-01-01

    Data obtained through 1970, some materials published during the first half of 1971, and conclusions of the Jupiter Radiation Belt Workshop held in July 1971 are presented. All the information on Jupiter was derived from data obtained at angular and spectral resolutions possible with Earth-based instrumentation or with sensors on aircraft, rockets, and balloons. The observations were made primarily in the visible, near visible, infrared, and radio portions of the electromagnetic spectrum. The information was assessed for the potential effects of the Jovian environment on spacecraft performance. The assessment was done independently for the three types of missions under consideration and formulated for overall spacecraft as well as for subsystem design.

  9. Jupiter's Auroras Acceleration Processes

    NASA Image and Video Library

    2017-09-06

    This image, created with data from Juno's Ultraviolet Imaging Spectrometer (UVS), marks the path of Juno's readings of Jupiter's auroras, highlighting the electron measurements that show the discovery of the so-called discrete auroral acceleration processes indicated by the "inverted Vs" in the lower panel (Figure 1). This signature points to powerful magnetic-field-aligned electric potentials that accelerate electrons toward the atmosphere to energies that are far greater than what drive the most intense aurora at Earth. Scientists are looking into why the same processes are not the main factor in Jupiter's most powerful auroras. https://photojournal.jpl.nasa.gov/catalog/PIA21937

  10. Voyager 1 examines Jupiter

    NASA Technical Reports Server (NTRS)

    1979-01-01

    An overview of the Voyager mission to Jupiter, Saturn, and possibly Uranus is presented. Scientific instruments onboard the spacecraft are described as well as methods used for their calibration and evaluation during the cruise phase of the mission. Experiments to be performed cover the following areas: imaging science, radio science, cosmic rays, ultraviolet spectroscopy, photopolarimetry, planetary radio astronomy, magnetic fields, low-energy charged particles, plasma science, and infrared radiometry and spectroscopy. A list of the satellites of Jupiter and their diameters, distances, and periods is included.

  11. Jupiter's Big Bang.

    ERIC Educational Resources Information Center

    McDonald, Kim A.

    1994-01-01

    Collision of a comet with Jupiter beginning July 16, 1994 will be observed by astronomers worldwide, with computerized information relayed to a center at the University of Maryland, financed by the National Aeronautics and Space Administration and National Science Foundation. Geologists and paleontologists also hope to learn more about earth's…

  12. Jupiter's Southern Lights

    NASA Image and Video Library

    2017-05-25

    The complexity and richness of Jupiter's "southern lights" (also known as auroras) are on display in this animation of false-color maps from NASA's Juno spacecraft. Auroras result when energetic electrons from the magnetosphere crash into the molecular hydrogen in the Jovian upper atmosphere. The data for this animation were obtained by Juno's Ultraviolet Spectrograph. The images are centered on the south pole and extend to latitudes of 50 degrees south. Each frame of the animation includes data from 30 consecutive Juno spins (about 15 minutes), just after the spacecraft's fifth close approach to Jupiter on February 2, 2017. The eight frames of the animation cover the period from 13:40 to 15:40 UTC at Juno. During that time, the spacecraft was receding from 35,000 miles to 153,900 miles (56,300 kilometers to 247,600 kilometers) above the aurora; this large change in distance accounts for the increasing fuzziness of the features. Jupiter's prime meridian is toward the bottom, and longitudes increase counterclockwise from there. The sun was located near the bottom at the start of the animation, but was off to the right by the end of the two-hour period. The red coloring of some of the features indicates that those emissions came from deeper in Jupiter's atmosphere; green and white indicate emissions from higher up in the atmosphere. Animations are available at https://photojournal.jpl.nasa.gov/catalog/PIA21643

  13. Jupiter Great Red Spot

    NASA Image and Video Library

    1996-02-01

    This dramatic view of Jupiter Great Red Spot and its surroundings was obtained by NASA Voyager 1 on Feb. 25, 1979. The colorful, wavy cloud pattern to the left of the Red Spot is a region of extraordinarily complex end variable wave motion. http://photojournal.jpl.nasa.gov/catalog/PIA00014

  14. Jupiter Great Red Spot

    NASA Image and Video Library

    1998-12-05

    This view of Jupiter was taken by Voyager 1. This image was taken through color filters and recombined to produce the color image. This photo was assembled from three black and white negatives by the Image Processing Lab at Jet Propulsion Laboratory. http://photojournal.jpl.nasa.gov/catalog/PIA01384

  15. A Transiting Jupiter Analog

    NASA Astrophysics Data System (ADS)

    Kipping, D. M.; Torres, G.; Henze, C.; Teachey, A.; Isaacson, H.; Petigura, E.; Marcy, G. W.; Buchhave, L. A.; Chen, J.; Bryson, S. T.; Sandford, E.

    2016-04-01

    Decadal-long radial velocity surveys have recently started to discover analogs to the most influential planet of our solar system, Jupiter. Detecting and characterizing these worlds is expected to shape our understanding of our uniqueness in the cosmos. Despite the great successes of recent transit surveys, Jupiter analogs represent a terra incognita, owing to the strong intrinsic bias of this method against long orbital periods. We here report on the first validated transiting Jupiter analog, Kepler-167e (KOI-490.02), discovered using Kepler archival photometry orbiting the K4-dwarf KIC-3239945. With a radius of (0.91+/- 0.02) {R}{{J}}, a low orbital eccentricity ({0.06}-0.04+0.10), and an equilibrium temperature of (131+/- 3) K, Kepler-167e bears many of the basic hallmarks of Jupiter. Kepler-167e is accompanied by three Super-Earths on compact orbits, which we also validate, leaving a large cavity of transiting worlds around the habitable-zone. With two transits and continuous photometric coverage, we are able to uniquely and precisely measure the orbital period of this post snow-line planet (1071.2323 ± 0.0006d), paving the way for follow-up of this K = 11.8 mag target.

  16. Jupiter's Big Bang.

    ERIC Educational Resources Information Center

    McDonald, Kim A.

    1994-01-01

    Collision of a comet with Jupiter beginning July 16, 1994 will be observed by astronomers worldwide, with computerized information relayed to a center at the University of Maryland, financed by the National Aeronautics and Space Administration and National Science Foundation. Geologists and paleontologists also hope to learn more about earth's…

  17. Radiation belts of jupiter.

    PubMed

    Stansberry, K G; White, R S

    1973-12-07

    Predictions of Jupiter's electron and proton radiation belts are based mainly on decimeter observations of 1966 and 1968. Extensive calculations modeling radial diffusion of particles inward from the solar wind and electron synchrotron radiation are used to relate the predictions and observations.

  18. Ammonia photolysis on Jupiter.

    NASA Technical Reports Server (NTRS)

    Nicodem, D. E.; Ferris, J. P.

    1973-01-01

    Ammonia photolysis under simulated Jovian conditions indicates that the photochemical reaction would rapidly convert all the ammonia of Jupiter to nitrogen even in a large excess of hydrogen. It is suggested that ammonia is observed because the planet's atmosphere is deep and hot and/or because electrical discharge phenomena are important.

  19. Thunderheads on Jupiter

    NASA Image and Video Library

    1997-09-08

    Scientists have spotted what appear to be thunderheads on Jupiter bright white cumulus clouds similar to those that bring thunderstorms on Earth - at the outer edges of Jupiter's Great Red Spot. Images from NASA's Galileo spacecraft now in orbit around Jupiter are providing new evidence that thunderstorms may be an important source of energy for Jupiter's winds that blow at more than 500 kilometers per hour (about 300 miles per hour). The photos were taken by Galileo's solid state imager camera on June 26, 1996 at a range of about 1.4 million kilometers (about 860,000 miles). The image at top is a mosaic of multiple images taken through near-infrared filters. False coloring in the image reveals cloud-top heights. High, thick clouds are white and high, thin clouds are pink. Low-altitude clouds are blue. The two black-and-white images at bottom are enlargements of the boxed area; the one on the right was taken 70 minutes after the image on the left. The arrows show where clouds have formed or dissipated in the short time between the images. The smallest clouds are tens of kilometers across. On Earth, moist convection in thunderstorms is a pathway through which solar energy, deposited at the surface, is transported and delivered to the atmosphere. Scientists at the California Institute of Technology analyzing data from Galileo believe that water, the most likely candidate for what composes these clouds on Jupiter, may be more abundant at the site seen here than at the Galileo Probe entry site, which was found to be unexpectedly dry. http://photojournal.jpl.nasa.gov/catalog/PIA00506

  20. Astronomy Explained

    NASA Astrophysics Data System (ADS)

    North, Gerald

    Every year large numbers of people take up the study of astronomy, mostly at amateur level. There are plenty of elementary books on the market, full of colourful photographs, but lacking in proper explanations of how and why things are as they are. Many people eventually wish to go beyond the 'coffee-table book' stage and study this fascinating subject in greater depth. This book is written for them. In addition, many people sit for public examinations in this subject each year and this book is also intended to be of use to them. All the topics from the GCSE syllabus are covered here, with sample questions at the end of each chapter. Astronomy Explained provides a comprehensive treatment of the subject in more depth than is usually found in elementary works, and will be of interest to both amateur astronomers and students of astronomy.

  1. Effects of the trinucleotide preceding the self-cleavage site on eggplant latent viroid hammerheads: differences in co- and post-transcriptional self-cleavage may explain the lack of trinucleotide AUC in most natural hammerheads

    PubMed Central

    Carbonell, Alberto; De la Peña, Marcos; Flores, Ricardo; Gago, Selma

    2006-01-01

    Eggplant latent viroid (ELVd) can form stable hammerhead structures in its (+) and (−) strands. These ribozymes have the longest helices I reported in natural hammerheads, with that of the ELVd (+) hammerhead being particularly stable (5/7 bp are G-C). Moreover, the trinucleotide preceding the self-cleavage site of this hammerhead is AUA, which together with GUA also found in some natural hammerheads, deviate from the GUC present in most natural hammerheads including the ELVd (−) hammerhead. When the AUA trinucleotide preceding the self-cleavage site of the ELVd (+) hammerhead was substituted by GUA and GUC, as well as by AUC (essentially absent in natural hammerheads), the values of the self-cleavage rate constants at low magnesium of the purified hammerheads were: ELVd-(+)-AUC≈ELVd-(+)-GUC>ELVd-(+)-GUA> ELVd-(+)-AUA. However, the ELVd-(+)-AUC hammerhead was the catalytically less efficient during in vitro transcription, most likely because of the transient adoption of catalytically-inactive metastable structures. These results suggest that natural hammerheads have been evolutionary selected to function co-transcriptionally, and provide a model explaining the lack of trinucleotide AUC preceding the self-cleavage site of most natural hammerheads. Comparisons with other natural hammerheads showed that the ELVd-(+)-GUC and ELVd-(+)-AUC hammerheads are the catalytically most active in a post-transcriptional context with low magnesium. PMID:17028097

  2. Chandra Probes High-Voltage Auroras on Jupiter

    NASA Astrophysics Data System (ADS)

    2005-03-01

    Scientists have obtained new insight into the unique power source for many of Jupiter's auroras, the most spectacular and active auroras in the Solar System. Extended monitoring of the giant planet with NASA's Chandra X-ray Observatory detected the presence of highly charged particles crashing into the atmosphere above its poles. X-ray spectra measured by Chandra showed that the auroral activity was produced by ions of oxygen and other elements that were stripped of most of their electrons. This implies that these particles were accelerated to high energies in a multimillion-volt environment above the planet's poles. The presence of these energetic ions indicates that the cause of many of Jupiter's auroras is different from auroras produced on Earth or Saturn. Chandra X-ray Image of Jupiter Chandra X-ray Image of Jupiter "Spacecraft have not explored the region above the poles of Jupiter, so X-ray observations provide one of the few ways to probe that environment," said Ron Elsner of the NASA Marshall Space Flight Center in Huntsville, Alabama, and lead author on a recently published paper describing these results in the Journal for Geophysical Research. "These results will help scientists to understand the mechanism for the power output from Jupiter's auroras, which are a thousand times more powerful than those on Earth." Electric voltages of about 10 million volts, and currents of 10 million amps - a hundred times greater than the most powerful lightning bolts - are required to explain the X-ray observations. These voltages would also explain the radio emission from energetic electrons observed near Jupiter by the Ulysses spacecraft. Schematic of Jupiter's Auroral Activity Production Schematic of Jupiter's Auroral Activity Production On Earth, auroras are triggered by solar storms of energetic particles, which disturb Earth's magnetic field. Gusts of particles from the Sun can also produce auroras on Jupiter, but unlike Earth, Jupiter has another way of producing

  3. Jupiter's Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow.

    A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest

  4. Jupiter's Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow.

    A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest

  5. Jupiter Ring Halo

    NASA Image and Video Library

    1998-03-26

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (km) per picture element (pixel) along the rings; however, because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow peering back toward the Sun; the ring was approximately 2,300,000 kilometers (km) away. The arc on the far right of the image is produced by sunlight scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age. Jupiter's ring system is composed of three parts -- a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, which lies exterior to the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the far left side of the figure. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. A faint mist of particles can be seen above and below the main rings; this vertically extended, toroidal "halo" is unusual in planetary rings, and is probably caused by electromagnetic forces which can push small grains out of the ring plane. Halo material is present across this entire image, implying that it reaches more than 27,000 km above the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. In order to accentuate faint features in the image, different brightnesses are shown through color, with the brightest being

  6. Jupiter: As a planet. [its physical characteristics and radio waves emitted from Jupiter

    NASA Technical Reports Server (NTRS)

    1975-01-01

    The planet Jupiter, its planetary mass and atmosphere, radio waves emitted from Jupiter, thermal radiation, internal structure of Jupiter, and the possibility of life on Jupiter are discussed. Educational study projects are included.

  7. Magnetospheres of earth and Jupiter after Pioneer 10

    NASA Technical Reports Server (NTRS)

    Prakash, A.; Brice, N.

    1975-01-01

    Possible reasons are discussed for the marked differences observed between the magnetospheres of earth and Jupiter, and a model of Jupiter's magnetosphere is proposed which can explain the observations of the Pioneer 10 mission. It is shown that the corotating plasma in Jupiter's plasmasphere is in the form of a flattened disk due to inertial forces and that Jupiter's magnetosphere is, in part, a rigidly rotating warped skew 'magnetodisk'. According to the proposed model, the inner part of the magnetosphere consists of a warped magnetodisk, the dipole field lines are modified by a ring current, and the equatorial plasma density increases with distance in the region beyond the synchronous orbit radius. Considerable attention is given to the effects resulting from spiraling of the magnetic-field lines, the tilt in the magnetic dipole, and the strong viscous interaction of the solar wind on the dawn side of the magnetosphere.

  8. Jupiter - Solid or Gaseous? Ask Juno

    NASA Astrophysics Data System (ADS)

    Ackerman, J. A., Jr.

    2015-12-01

    Data from Cassini, Galileo, S-L 9 and Ulysses suggest Jupiter and Saturn are solid, frozen, Methane Gas Hydrate (MGH) planets. The bulk of these giants formed slow and cold by the natural accretion of snowflakes at their current orbital radii in the presence of methane, forming rigid incompressible bodies. MGH, (CH4)8(H2O)46 (d=0.9), is consistent with the abundances of the elements comprising the Earth (H>O>C). Their combined MGH comprises >250 earth-masses of H2O. Jupiter (d=1.33) incorporated most of the heavy elements in the nascent solar system, exemplified by an enormously enhanced D/H. The temperature excess of Jupiter's atmosphere is the result of an impact ~6,000 years BP, triggering an incredibly energetic fusion explosion which ejected the masses of the proto-Galilean moons. It also initiated a continuing fusion furnace in the crater producing a jet of hot gases extending >2x106 km, beyond Callisto. The jet has slowly diminished over 6,000 years, resulting in the differences in the four Galilean Moons. The mass ejection (ang. mom.) slowed Jupiter's rotation until ~1930, currently interpreted as a drift of the Great Red Spot. A diminishing fusion reaction (D + p → 3He + γ) continues to this day, producing Jupiter's atmospheric 'temperature excess'. Jupiter's rapid rotation deflects the rising vortex of hot gases from the fusion reaction horizontally, driving multiple zonal vortices, constrained by the frozen MGH surface <1000 km below the cloud tops. It appears as the tilted Great Red Spot (GRS), ~30,000 km to the west of the crater at 22 o S Lat., which has remained unchanged in the last 350 years - impossible due to the enormous Coliolis effect. Streams of 3He produced in the fusion reaction exiting Jupiter through the center of the GRS have been detected by the Galileo probe and orbiter, Ulysses, and Cassini. The fusion releases methane, also heavy elements which oxidize as they rise, producing the cloud-top colors. The MGH hypothesis explains the

  9. Polarized Light from Jupiter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These images taken through the wide angle camera near closest approach in the deep near-infrared methane band, combined with filters which sense electromagnetic radiation of orthogonal polarization, show that the light from the poles is polarized. That is, the poles appear bright in one image, and dark in the other. Polarized light is most readily scattered by aerosols. These images indicate that the aerosol particles at Jupiter's poles are small and likely consist of aggregates of even smaller particles, whereas the particles at the equator and covering the Great Red Spot are larger. Images like these will allow scientists to ascertain the distribution, size and shape of aerosols, and consequently, the distribution of heat, in Jupiter's atmosphere.

  10. Stormy Day at Jupiter

    NASA Image and Video Library

    2017-05-25

    Small bright clouds dot Jupiter's entire south tropical zone in this image acquired by JunoCam on NASA's Juno spacecraft on May 19, 2017, at an altitude of 7,990 miles (12,858 kilometers). Although the bright clouds appear tiny in this vast Jovian cloudscape, they actually are cloud towers roughly 30 miles (50 kilometers) wide and 30 miles (50 kilometers) high that cast shadows on the clouds below. On Jupiter, clouds this high are almost certainly composed of water and/or ammonia ice, and they may be sources of lightning. This is the first time so many cloud towers have been visible, possibly because the late-afternoon lighting is particularly good at this geometry. https://photojournal.jpl.nasa.gov/catalog/PIA21647

  11. Jupiter Red 'Monet'

    NASA Image and Video Library

    2017-08-30

    Citizen scientist David Englund created this avant-garde Jovian artwork using data from the JunoCam imager on NASA's Juno spacecraft. The unique interpretation of Jupiter's Great Red Spot was done in a style that pays tribute to French Impressionist painter Claude Monet. The original image was taken on July 10, 2017 at 7:12 p.m. PDT (10:12 p.m. EDT), as the Juno spacecraft performed its 7th close flyby of Jupiter. At the time the image was taken, the spacecraft was 10,274 miles (16,535 kilometers) from the tops of the clouds of the planet, at a latitude of -36.9 degrees. https://photojournal.jpl.nasa.gov/catalog/PIA21779

  12. Closing in on Jupiter

    NASA Image and Video Library

    2016-06-16

    On June 16, NASA discussed the status of its Juno mission to Jupiter during a news briefing at the agency’s headquarters, in Washington DC. This Fourth of July, the solar-powered Juno spacecraft will arrive at our solar system’s most massive planet after an almost five-year journey. Once in Jupiter’s orbit, the spacecraft will circle the Jovian world 37 times during 20 months, skimming to within 3,100 miles (5,000 kilometers) above the cloud tops. This is the first time a spacecraft will orbit the poles of Jupiter, providing new answers to ongoing mysteries about the planet’s core, composition and magnetic fields.

  13. Jupiter 7th Pearl

    NASA Image and Video Library

    2016-12-14

    This image, taken by the JunoCam imager on NASA's Juno spacecraft, highlights the seventh of eight features forming a 'string of pearls' on Jupiter -- massive counterclockwise rotating storms that appear as white ovals in the gas giant's southern hemisphere. Since 1986, these white ovals have varied in number from six to nine. There are currently eight white ovals visible. Since 1986, these white ovals have varied in number from six to nine. There are currently eight white ovals visible. The image was taken on Dec. 11, 2016, at 9:27 a.m. PST (12:27 EST) as the Juno spacecraft performed its third close flyby of the planet. At the time the image was taken, the spacecraft was about 15,300 miles (24,600 kilometers) from Jupiter. http://photojournal.jpl.nasa.gov/catalog/PIA21219

  14. Jupiter's Water Worlds

    NASA Technical Reports Server (NTRS)

    Pappalardo, R. T.

    2004-01-01

    When the twin Voyager spacecraft cruised past Jupiter in 1979, they did more than rewrite the textbooks on the giant planet. Their cameras also unveiled the astounding diversity of the four planet-size moons of ice and stone known as the Galilean satellites. The Voyagers revealed the cratered countenance of Callisto, the valleys and ridges of Ganymede, the cracked face of Europa, and the spewing volcanoes of Io. But it would take a spacecraft named for Italian scientist Galileo, who discovered the moons in 1610, to reveal the true complexity of these worlds and to begin to divulge their interior secrets. Incredibly, the Galileo data strongly suggest that Jupiter's three large icy moons (all but rocky Io) hide interior oceans.

  15. Jupiter Down Under

    NASA Image and Video Library

    2016-09-02

    This image from NASA's Juno spacecraft provides a never-before-seen perspective on Jupiter's south pole. The JunoCam instrument acquired the view on August 27, 2016, when the spacecraft was about 58,700 miles (94,500 kilometers) above the polar region. At this point, the spacecraft was about an hour past its closest approach, and fine detail in the south polar region is clearly resolved. Unlike the equatorial region's familiar structure of belts and zones, the poles are mottled by clockwise and counterclockwise rotating storms of various sizes, similar to giant versions of terrestrial hurricanes. The south pole has never been seen from this viewpoint, although the Cassini spacecraft was able to observe most of the polar region at highly oblique angles as it flew past Jupiter on its way to Saturn in 2000. http://photojournal.jpl.nasa.gov/catalog/PIA21032

  16. Jupiter-Io Montage

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This is a montage of New Horizons images of Jupiter and its volcanic moon Io, taken during the spacecraft's Jupiter flyby in early 2007. The Jupiter image is an infrared color composite taken by the spacecraft's near-infrared imaging spectrometer, the Linear Etalon Imaging Spectral Array (LEISA) at 1:40 UT on Feb. 28, 2007. The infrared wavelengths used (red: 1.59 um, green: 1.94 um, blue: 1.85 um) highlight variations in the altitude of the Jovian cloud tops, with blue denoting high-altitude clouds and hazes, and red indicating deeper clouds. The prominent bluish-white oval is the Great Red Spot. The observation was made at a solar phase angle of 75 degrees but has been projected onto a crescent to remove distortion caused by Jupiter's rotation during the scan. The Io image, taken at 00:25 UT on March 1st 2007, is an approximately true-color composite taken by the panchromatic Long-Range Reconnaissance Imager (LORRI), with color information provided by the 0.5 um ('blue') and 0.9 um ('methane') channels of the Multispectral Visible Imaging Camera (MVIC). The image shows a major eruption in progress on Io's night side, at the northern volcano Tvashtar. Incandescent lava glows red beneath a 330-kilometer high volcanic plume, whose uppermost portions are illuminated by sunlight. The plume appears blue due to scattering of light by small particles in the plume

    This montage appears on the cover of the Oct. 12, 2007, issue of Science magazine.

  17. The atmosphere of Jupiter

    NASA Technical Reports Server (NTRS)

    Ingersoll, A. P.

    1976-01-01

    Current information on the neutral atmosphere of Jupiter is reviewed, with approximately equal emphasis on composition and thermal structure on one hand, and markings and dynamics on the other. Studies based on Pioneer 10 and 11 data are used to refine the atmospheric model. Data on the interior are reviewed for the information they provide on the deep atmosphere. The markings and dynamics are discussed with emphasis on qualitative relationships and analogies with phenomena in earth's atmosphere.

  18. Rubble around Jupiter

    NASA Astrophysics Data System (ADS)

    Showstack, Randy

    NASA's Jet Propulsion Laboratory has announced that Amalthea, a 270-km-long, potato-shaped inner moon of Jupiter, "apparently is a loosely packed pile of rubble," with empty space where the rubble does not fit well together.This is among the new findings about the moon announced by JPL astronomer John Anderson and his colleagues on 9 December at the AGU Fall Meeting in San Francisco.

  19. Jupiter-Io Montage

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This is a montage of New Horizons images of Jupiter and its volcanic moon Io, taken during the spacecraft's Jupiter flyby in early 2007. The Jupiter image is an infrared color composite taken by the spacecraft's near-infrared imaging spectrometer, the Linear Etalon Imaging Spectral Array (LEISA) at 1:40 UT on Feb. 28, 2007. The infrared wavelengths used (red: 1.59 um, green: 1.94 um, blue: 1.85 um) highlight variations in the altitude of the Jovian cloud tops, with blue denoting high-altitude clouds and hazes, and red indicating deeper clouds. The prominent bluish-white oval is the Great Red Spot. The observation was made at a solar phase angle of 75 degrees but has been projected onto a crescent to remove distortion caused by Jupiter's rotation during the scan. The Io image, taken at 00:25 UT on March 1st 2007, is an approximately true-color composite taken by the panchromatic Long-Range Reconnaissance Imager (LORRI), with color information provided by the 0.5 um ('blue') and 0.9 um ('methane') channels of the Multispectral Visible Imaging Camera (MVIC). The image shows a major eruption in progress on Io's night side, at the northern volcano Tvashtar. Incandescent lava glows red beneath a 330-kilometer high volcanic plume, whose uppermost portions are illuminated by sunlight. The plume appears blue due to scattering of light by small particles in the plume

    This montage appears on the cover of the Oct. 12, 2007, issue of Science magazine.

  20. Physics of Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Hamilton, Douglas P.; Krueger, H.

    2008-05-01

    Thebe's gossamer ring, the outermost and faintest of Jupiter's rings, extends outward by at least half a jovian radius from its source satellite while maintaining a constant vertical thickness. This structure is created by an electromagnetic perturbation known as a shadow resonance (Hamilton 2003, DPS meeting #35, #11.09). A shadow resonance arises from the abrupt shutoff of photoelectric charging when a dust particle enters Jupiter's shadow which, in turn, affects the strength of the electromagnetic perturbation from the planet's intense magnetic field. The result is a coupled oscillation between a particle's orbital eccentricity and its semimajor axis. Ring material spreads outward from Thebe while maintaining its vertical thickness just as observed by Galileo imaging. In addition to cameras, the Galileo spacecraft was also equipped with dust and plasma detectors. The spacecraft made two passes through the ring and its dust detector found that 1) dust fluxes drop immediately interior to Thebe's orbit, 2) some grains have inclinations in excess of 20 degrees and 3) submicron particles are present in the Amalthea ring in much greater numbers than in the Thebe ring. These findings can all be explained in the context of our shadow resonance model: the inner boundary is a direct consequence of the conservation of the Electromagnetic Jacobi Constant, the high inclinations are forced by a vertical version of the shadow resonance, and the excess submicron particles are a consequence of the weakening of electromagnetic forces in the vicinity of synchronous orbit. In this talk, we will present the data sets as well as detailed numerical simulations that back up these claims.

  1. Voyager picture of Jupiter

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA's Voyager 1 took this picture of the planet Jupiter on Saturday, Jan. 6, the first in its three-month-long, close-up investigation of the largest planet. The spacecraft, flying toward a March 5 closest approach, was 35.8 million miles (57.6 million kilometers) from Jupiter and 371.7 million miles (598.2 million kilometers) from Earth when the picture was taken. As the Voyager cameras begin their meteorological surveillance of Jupiter, they reveal a dynamic atmosphere with more convective structure than had previously been thought. While the smallest atmospheric features seen in this picture are still as large as 600 miles (1,000 kilometers) across, Voyager will be able to detect individual storm systems as small as 3 miles (5 kilometers) at closest approach. The Great Red Spot can be seen near the limb at the far right. Most of the other features are too small to be seen in terrestrial telescopes. This picture was transmitted to the Jet Propulsion Laboratory through the Deep Space Network's tracking station at Madrid, Spain. The Voyager Project is managed for NASA by Caltech's Jet Propulsion Laboratory.

  2. Jupiter Equatorial Region

    NASA Image and Video Library

    1998-03-06

    This photographic mosaic of images from NASA's Galileo spacecraft covers an area of 34,000 kilometers by 22,000 kilometers (about 21,100 by 13,600 miles) in Jupiter's equatorial region. The dark region near the center of the mosaic is an equatorial "hotspot" similar to the site where the Galileo Probe parachuted into Jupiter's atmosphere in December 1995. These features are holes in the bright, reflective, equatorial cloud layer where heat from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright oval in the upper right of the mosaic as well as the other smaller bright features are examples of upwelling of moist air and condensation. These images were taken on December 17, 1996, at a range of 1.5 million kilometers (about 930,000 miles) by the Solid State Imaging camera system aboard Galileo. North is at the top. The mosaic covers latitudes 1 to 19 degrees and is centered at longitude 336 degrees west. The smallest resolved features are tens of kilometers in size. http://photojournal.jpl.nasa.gov/catalog/PIA00604

  3. Understanding Jupiter's interior

    NASA Astrophysics Data System (ADS)

    Militzer, Burkhard; Soubiran, François; Wahl, Sean M.; Hubbard, William

    2016-09-01

    This article provides an overview of how models of giant planet interiors are constructed. We review measurements from past space missions that provided constraints for the interior structure of Jupiter. We discuss typical three-layer interior models that consist of a dense central core and an inner metallic and an outer molecular hydrogen-helium layer. These models rely heavily on experiments, analytical theory, and first-principles computer simulations of hydrogen and helium to understand their behavior up to the extreme pressures ˜10 Mbar and temperatures ˜10,000 K. We review the various equations of state used in Jupiter models and compare them with shock wave experiments. We discuss the possibility that helium rain, core erosion, and double diffusive convection have affected the structure and evolution of giant planets. In July 2016 the Juno spacecraft entered orbit around Jupiter, promising high-precision measurements of the gravitational field that will allow us to test our understanding of gas giant interiors better than ever before.

  4. Voyager 2 Jupiter Eruption Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This movie records an eruptive event in the southern hemisphere of Jupiter over a period of 8 Jupiter days. Prior to the event, an undistinguished oval cloud mass cruised through the turbulent atmosphere. The eruption occurs over avery short time at the very center of the cloud. The white eruptive material is swirled about by the internal wind patterns of the cloud. As a result of the eruption, the cloud then becomes a type of feature seen elsewhere on Jupiter known as 'spaghetti bowls'.

    As Voyager 2 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 8 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Violet filter around May 6, 1979. The spacecraft was about 50 million kilometers from Jupiter at that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  5. Thunderheads on Jupiter

    NASA Technical Reports Server (NTRS)

    1996-01-01

    Scientists have spotted what appear to be thunderheads on Jupiter bright white cumulus clouds similar to those that bring thunderstorms on Earth - at the outer edges of Jupiter's Great Red Spot. Images from NASA's Galileo spacecraft now in orbit around Jupiter are providing new evidence that thunderstorms may be an important source of energy for Jupiter's winds that blow at more than 500 kilometers per hour (about 300 miles per hour). The photos were taken by Galileo's solid state imager camera on June 26, 1996 at a range of about 1.4 million kilometers (about 860,000 miles).

    The image at top is a mosaic of multiple images taken through near-infrared filters. False coloring in the image reveals cloud-top heights. High, thick clouds are white and high, thin clouds are pink. Low-altitude clouds are blue. The two black-and-white images at bottom are enlargements of the boxed area; the one on the right was taken 70 minutes after the image on the left. The arrows show where clouds have formed or dissipated in the short time between the images. The smallest clouds are tens of kilometers across.

    On Earth, moist convection in thunderstorms is a pathway through which solar energy, deposited at the surface, is transported and delivered to the atmosphere. Scientists at the California Institute of Technology analyzing data from Galileo believe that water, the most likely candidate for what composes these clouds on Jupiter, may be more abundant at the site seen here than at the Galileo Probe entry site, which was found to be unexpectedly dry.

    The Galileo mission is managed by the Jet Propulsion Laboratory for NASA's Office of Space Science, Washington, D.C. .

    This image and other images and data received from Galileo are posted on the Galileo mission home page on the World Wide Web at http://galileo.jpl.nasa.gov. Background information and educational context for the images can be found at http://www.jpl.nasa.gov/galileo/sepo

  6. Jupiter small satellite montage

    NASA Technical Reports Server (NTRS)

    2000-01-01

    A montage of images of the small inner moons of Jupiter from the camera onboard NASA's Galileo spacecraft shows the best views obtained of these moons during Galileo's 11th orbit around the giant planet in November 1997. At that point, Galileo was completing its first two years in Jupiter orbit--known as the Galileo 'prime mission'--and was about to embark on a successful two-year extension, called the Galileo Europa Mission.

    The top two images show the moon Thebe. Thebe rotates by approximately 50 degrees between the time these two images were taken, so that the same prominent impact crater is seen in both views; this crater, which has been given the provisional name Zethus, is near the point on Thebe that faces permanently away from Jupiter.

    The next two images show the moon Amalthea; they were taken with the Sun directly behind the observer, an alignment that emphasizes patterns of intrinsically bright or dark surface material. The third image from the top is a view of Amalthea's leading side, the side of the moon that 'leads' as Amalthea moves in its orbit around Jupiter. This image looks 'noisy' because it was obtained serendipitously during an observation of the Jovian satellite Io (Amalthea and Io shared the same camera frame but the image was exposed for bright Io rather than for the much darker Amalthea). The fourth image from the top emphasizes prominent 'spots' of relatively bright material that are located near the point on Amalthea that faces permanently away from Jupiter. The bottom image is a view of the tiny moon Metis.

    In all the images, north is approximately up, and the moons are shown in their correct relative sizes. The images are, from top to bottom: Thebe taken on November 7, 1997 at a range of 504,000 kilometers (about 313,000 miles); Thebe on November 7, 1997 at a range of 548,000 kilometers (about 340,000 miles); Amalthea on November 6, 1997 at a range of about 650,000 kilometers (about 404,000 miles); Amalthea on November

  7. Too Little, Too Late: How the Tidal Evolution of Hot Jupiters Affects Transit Surveys of Clusters

    NASA Technical Reports Server (NTRS)

    Debes, John H.; Jackson, Brian

    2010-01-01

    The tidal evolution of hot Jupiters may change the efficiency of transit surveys of stellar clusters. The orbital decay that hot Jupiters suffer may result in their destruction, leaving fewer transiting planets in older clusters. We calculate the impact tidal evolution has for different assumed stellar populations, including that of 47 Tuc, a globular cluster that was the focus of an intense HST search for transits. We find that in older clusters one expects to detect fewer transiting planets by a factor of two for surveys sensitive to Jupiter-like planets in orbits out to 0.5 AU, and up to a factor of 25 for surveys sensitive to Jupiter-like planets in orbits out to 0.08 AU. Additionally, tidal evolution affects the distribution of transiting planets as a function of semi-major axis, producing larger orbital period gaps for transiting planets as the age of the cluster increases. Tidal evolution can explain the lack of detected exoplanets in 47 Tuc without invoking other mechanisms. Four open clusters residing within the Kepler fields of view have ages that span 0.4-8 Gyr-if Kepler can observe a significant number of planets in these clusters, it will provide key tests for our tidal evolution hypothesis. Finally, our results suggest that observers wishing to discover transiting planets in clusters must have sufficient accuracy to detect lower mass planets, search larger numbers of cluster members, or have longer observation windows to be confident that a significant number of transits will occur for a population of stars.

  8. TOO LITTLE, TOO LATE: HOW THE TIDAL EVOLUTION OF HOT JUPITERS AFFECTS TRANSIT SURVEYS OF CLUSTERS

    SciTech Connect

    Debes, John H.; Jackson, Brian

    2010-11-10

    The tidal evolution of hot Jupiters may change the efficiency of transit surveys of stellar clusters. The orbital decay that hot Jupiters suffer may result in their destruction, leaving fewer transiting planets in older clusters. We calculate the impact tidal evolution has for different assumed stellar populations, including that of 47 Tuc, a globular cluster that was the focus of an intense Hubble Space Telescope search for transits. We find that in older clusters, one expects to detect fewer transiting planets by a factor of 2 for surveys sensitive to Jupiter-like planets in orbits out to 0.5 AU, and up to a factor of 25 for surveys sensitive to Jupiter-like planets in orbits out to 0.08 AU. Additionally, tidal evolution affects the distribution of transiting planets as a function of the semimajor axis, producing larger orbital period gaps for transiting planets as the age of the cluster increases. Tidal evolution can explain the lack of detected exoplanets in 47 Tuc without invoking other mechanisms. Four open clusters residing within the Kepler fields of view have ages that span 0.4-8 Gyr-if Kepler can observe a significant number of planets in these clusters, it will provide key tests for our tidal evolution hypothesis. Finally, our results suggest that observers wishing to discover transiting planets in clusters must have sufficient accuracy to detect lower mass planets, search larger numbers of cluster members, or have longer observation windows to be confident that a significant number of transits will occur for a population of stars.

  9. High Resolution Globe of Jupiter

    NASA Image and Video Library

    2001-01-30

    This true-color simulated view of Jupiter is composed of 4 images taken by NASA's Cassini spacecraft on December 7, 2000. To illustrate what Jupiter would have looked like if the cameras had a field-of-view large enough to capture the entire planet, the cylindrical map was projected onto a globe. The resolution is about 144 kilometers (89 miles) per pixel. Jupiter's moon Europa is casting the shadow on the planet. https://photojournal.jpl.nasa.gov/catalog/PIA02873

  10. A Day on Jupiter (Animation)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This 'movie' strings 11 images of Jupiter captured by the New Horizons Long Range Reconnaissance Imager (LORRI) on January 9, 2007, when the spacecraft was about 80 million kilometers (49.6 million miles) from the giant planet. The sequence covers a full 10-hour rotation of Jupiter, during which the moons Ganymede and Io -- as well as the shadows they cast on Jupiter -- move across the camera's field of view.

  11. A historical interpretation of the study of the visible cloud morphology on the planet Jupiter: 1610-1878

    NASA Astrophysics Data System (ADS)

    Hockey, Thomas Arnold

    The majority of the literature discussing the perceived physical appearance of Jupiter published prior to 1878 was examined in order to determine to what extent observations were biased by technical limitations and preconceptions of their day and, in lieu of these, how useful this body of work is in characterizing the behavior of the Jovian upper atmosphere over the last three hundred years. The biographies of the historical observers; their instrumentation, available viewing conditions, and observational techniques; their means of communication with their fellows; and the primary interpretive references available to their libraries were investigated in order to attempt to explain discrepancies and agreement between what was reported in pre-photographic times and what is presently seen. It was found that nearly all of the prominent feature-types found on Jupiter today existed during the nineteenth century and, in some cases, earlier. The longevity and frequency of the appearance of features can not be accurately determined from the time before objective surveys of the planet were organized. This is because, during each apparition of Jupiter, nonprofessional part-time observers, working independently chose to use their finite time and resources to follow the progress of specific discoveries on its disk to the exclusion of the rest of the planet. Interpretation of Jovian features were subject to three major impediments: the belief in and search for a solid surface of Jupiter at moderate depth below the clouds; a lack of appreciation for the two or more orders of magnitude differences of scale between the dimensions of Jupiter's area, mass, and properties of its atmosphere compared to those of the Earth; and an inability to differentiate between real and phantom features watched through seeing-limited telescopes.

  12. Aurora Borealis on Jupiter

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This image, taken by NASA's Galileo spacecraft, shows the darkside of Jupiter, the part not illuminated by sunlight. The curved line crossing from the lower left to the upper right is the auroral arc on the horizon. With north at the top of the image, the central part of the auroral arc has a latitude of 57 degrees north. When this same region was imaged 30 seconds later, the central part had changed. The left and right boxes below show a magnified view of the central region at the earlier and later times, respectively. The aurora is dynamic on Jupiter, just as it is here on Earth. The eerie, glowing light is created when molecules in the upper atmosphere are struck by charge particles from the space around Jupiter. Fluctuations in the charged particle flow cause variations in the auroral emission.

    This image was part of a multi-instrument set of observations made as Galileo flew through a region of space rich in charged particles. The particles follow the magnetic field and, in this case, the spacecraft was flying through the particular field line that was imaged. With these observations, scientists hope to learn more about the particles and their interaction with the molecules in the atmosphere. This image provides a severe test of the camera optics. The overexposed region at the lower right is the illuminated part of the planet, which is much brighter than the aurora. When light from this region is scattered into the telescope, it creates a diffuse background. The long exposure subjects the detector to more cosmic rays than usual. These create spikes, the bright dots that are sprinkled throughout the image. These images were taken in the clear filter of the solid state imaging (CCD) system aboard the Galileo spacecraft on Nov. 5, 1996. Each pixel subtends a square about 30 kilometers (18.5 miles) throughout the image. The range is 1.433 million kilometers (0.89 million miles).

    Launched in October 1989, Galileo entered orbit around Jupiter on Dec. 7, 1995

  13. The 'Face' of Jupiter

    NASA Image and Video Library

    2017-06-29

    JunoCam images aren't just for art and science -- sometimes they are processed to bring a chuckle. This image, processed by citizen scientist Jason Major, is titled "Jovey McJupiterface." By rotating the image 180 degrees and orienting it from south up, two white oval storms turn into eyeballs, and the "face" of Jupiter is revealed. The original image was acquired by JunoCam on NASA's Juno spacecraft on May 19, 2017 at 11:20 a.m. PT (2: 20 p.m. ET) from an altitude of 12,075 miles (19,433 kilometers). https://photojournal.jpl.nasa.gov/catalog/PIA21394

  14. Colors on Jupiter

    NASA Technical Reports Server (NTRS)

    Owen, T.; Terrile, R. J.

    1981-01-01

    The colors present in the clouds of Jupiter at the time of the Voyager encounters are described as they appear in high resolution images. It is shown that latitude, altitude and dwelltime are all critical factors in determining which colors appear where, although the identities of the responsible chromophores remain unestablished. Simultaneous ground-based 5 micron observations are used to determine the relative altitudes of the cloud systems which are characterized as white clouds, tawny clouds, dark brown cloud belts, and blue-grey hot spots in equatorial regions. Correlations between cloud color and certain latitudes have been maintained for decades, which suggests the importance of the internal energy source.

  15. Colors on Jupiter

    NASA Technical Reports Server (NTRS)

    Owen, T.; Terrile, R. J.

    1981-01-01

    The colors present in the clouds of Jupiter at the time of the Voyager encounters are described as they appear in high resolution images. It is shown that latitude, altitude and dwelltime are all critical factors in determining which colors appear where, although the identities of the responsible chromophores remain unestablished. Simultaneous ground-based 5 micron observations are used to determine the relative altitudes of the cloud systems which are characterized as white clouds, tawny clouds, dark brown cloud belts, and blue-grey hot spots in equatorial regions. Correlations between cloud color and certain latitudes have been maintained for decades, which suggests the importance of the internal energy source.

  16. Jupiter and Three Galilean Satellites

    NASA Image and Video Library

    1999-03-06

    Jupiter, its Great Red Spot and three of its four largest satellites are visible in this photo taken Feb. 5, 1979, by Voyager 1. Io, Europa, and Callisto are seen against Jupiter disk. http://photojournal.jpl.nasa.gov/catalog/PIA00358

  17. Jupiter: Lord of the Planets.

    ERIC Educational Resources Information Center

    Kaufmann, William

    1984-01-01

    Presents a chapter from an introductory college-level astronomy textbook in which full-color photographs and numerous diagrams highlight an extensive description of the planet Jupiter. Topics include Jupiter's geology, rotation, magnetic field, atmosphere (including clouds and winds), and the Great Red Spot. (DH)

  18. Jupiter: Lord of the Planets.

    ERIC Educational Resources Information Center

    Kaufmann, William

    1984-01-01

    Presents a chapter from an introductory college-level astronomy textbook in which full-color photographs and numerous diagrams highlight an extensive description of the planet Jupiter. Topics include Jupiter's geology, rotation, magnetic field, atmosphere (including clouds and winds), and the Great Red Spot. (DH)

  19. Pioneer 11 Encounter. [with Jupiter

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Pioneer 11's encounter with Jupiter is discussed in detail. The scientific experiments carried out on the probe are described along with the instruments used. Tables are included which provide data on the times of experiments, encounters, and the distances from Jupiter. Educational study projects are also given.

  20. CAPTURE OF TROJANS BY JUMPING JUPITER

    SciTech Connect

    Nesvorny, David; Vokrouhlicky, David; Morbidelli, Alessandro

    2013-05-01

    Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to {approx}5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) Multiplication-Sign 10{sup -7} for each particle in the original transplanetary disk, implying that the disk contained (3-4) Multiplication-Sign 10{sup 7} planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M{sub disk} {approx} 14-28 M{sub Earth}, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

  1. Capture of irregular satellites at Jupiter

    SciTech Connect

    Nesvorný, David; Vokrouhlický, David; Deienno, Rogerio

    2014-03-20

    The irregular satellites of outer planets are thought to have been captured from heliocentric orbits. The exact nature of the capture process, however, remains uncertain. We examine the possibility that irregular satellites were captured from the planetesimal disk during the early solar system instability when encounters between the outer planets occurred. Nesvorný et al. already showed that the irregular satellites of Saturn, Uranus, and Neptune were plausibly captured during planetary encounters. Here we find that the current instability models present favorable conditions for capture of irregular satellites at Jupiter as well, mainly because Jupiter undergoes a phase of close encounters with an ice giant. We show that the orbital distribution of bodies captured during planetary encounters provides a good match to the observed distribution of irregular satellites at Jupiter. The capture efficiency for each particle in the original transplanetary disk is found to be (1.3-3.6) × 10{sup –8}. This is roughly enough to explain the observed population of jovian irregular moons. We also confirm Nesvorný et al.'s results for the irregular satellites of Saturn, Uranus, and Neptune.

  2. Capture of Trojans by Jumping Jupiter

    NASA Astrophysics Data System (ADS)

    Nesvorný, David; Vokrouhlický, David; Morbidelli, Alessandro

    2013-05-01

    Jupiter Trojans are thought to be survivors of a much larger population of planetesimals that existed in the planetary region when planets formed. They can provide important constraints on the mass and properties of the planetesimal disk, and its dispersal during planet migration. Here, we tested a possibility that the Trojans were captured during the early dynamical instability among the outer planets (aka the Nice model), when the semimajor axis of Jupiter was changing as a result of scattering encounters with an ice giant. The capture occurs in this model when Jupiter's orbit and its Lagrange points become radially displaced in a scattering event and fall into a region populated by planetesimals (that previously evolved from their natal transplanetary disk to ~5 AU during the instability). Our numerical simulations of the new capture model, hereafter jump capture, satisfactorily reproduce the orbital distribution of the Trojans and their total mass. The jump capture is potentially capable of explaining the observed asymmetry in the number of leading and trailing Trojans. We find that the capture probability is (6-8) × 10-7 for each particle in the original transplanetary disk, implying that the disk contained (3-4) × 107 planetesimals with absolute magnitude H < 9 (corresponding to diameter D = 80 km for a 7% albedo). The disk mass inferred from this work, M disk ~ 14-28 M Earth, is consistent with the mass deduced from recent dynamical simulations of the planetary instability.

  3. Small Friends of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Nunez, Luis Ernesto; Johnson, John A.

    2017-01-01

    Hot Jupiters are Jupiter-sized gas giant exoplanets that closely orbit their host star in periods of about 10 days or less. Early models hypothesized that these exoplanets formed away from the star, then over time drifted to their characteristically closer locations. However, new theories predict that Hot Jupiters form at their close proximity during the process of core accretion (Batygin et al. 2015). In fact, a super-Earth and a Neptune-sized exoplanet have already been detected in the Hot Jupiter-hosting star WASP-47 (Becker et al. 2015). We will present our analysis of radial velocity time series plots to determine whether low-mass, short-period planets have been previously overlooked in systems of stars which host Hot Jupiters.The SAO REU program is funded in part by the National Science Foundation REU and Department of Defense ASSURE programs under NSF Grant no. 1262851.

  4. Hubble Views Ancient Storm in the Atmosphere of Jupiter - Montage

    NASA Technical Reports Server (NTRS)

    1999-01-01

    When 17th-century astronomers first turned their telescopes to Jupiter, they noted a conspicuous reddish spot on the giant planet. This Great Red Spot is still present in Jupiter's atmosphere, more than 300 years later. It is now known that it is a vast storm, spinning like a cyclone. Unlike a low-pressure hurricane in the Caribbean Sea, however, the Red Spot rotates in a counterclockwise direction in the southern hemisphere, showing that it is a high-pressure system. Winds inside this Jovian storm reach speeds of about 270 mph.

    The Red Spot is the largest known storm in the Solar System. With a diameter of 15,400 miles, it is almost twice the size of the entire Earth and one-sixth the diameter of Jupiter itself.

    The long lifetime of the Red Spot may be due to the fact that Jupiter is mainly a gaseous planet. It possibly has liquid layers, but lacks a solid surface, which would dissipate the storm's energy, much as happens when a hurricane makes landfall on the Earth. However, the Red Spot does change its shape, size, and color, sometimes dramatically. Such changes are demonstrated in high-resolution Wide Field and Planetary Cameras 1 & 2 images of Jupiter obtained by NASA's Hubble Space Telescope, and presented here by the Hubble Heritage Project team. The mosaic presents a series of pictures of the Red Spot obtained by Hubble between 1992 and 1999 (see PIA01594 thru PIA01599 and PIA02400 thru PIA02402 for individual images).

    Astronomers study weather phenomena on other planets in order to gain a greater understanding of our own Earth's climate. Lacking a solid surface, Jupiter provides us with a laboratory experiment for observing weather phenomena under very different conditions than those prevailing on Earth. This knowledge can also be applied to places in the Earth's atmosphere that are over deep oceans, making them more similar to Jupiter's deep atmosphere.

  5. Hubble Views Ancient Storm in the Atmosphere of Jupiter - Montage

    NASA Technical Reports Server (NTRS)

    1999-01-01

    When 17th-century astronomers first turned their telescopes to Jupiter, they noted a conspicuous reddish spot on the giant planet. This Great Red Spot is still present in Jupiter's atmosphere, more than 300 years later. It is now known that it is a vast storm, spinning like a cyclone. Unlike a low-pressure hurricane in the Caribbean Sea, however, the Red Spot rotates in a counterclockwise direction in the southern hemisphere, showing that it is a high-pressure system. Winds inside this Jovian storm reach speeds of about 270 mph.

    The Red Spot is the largest known storm in the Solar System. With a diameter of 15,400 miles, it is almost twice the size of the entire Earth and one-sixth the diameter of Jupiter itself.

    The long lifetime of the Red Spot may be due to the fact that Jupiter is mainly a gaseous planet. It possibly has liquid layers, but lacks a solid surface, which would dissipate the storm's energy, much as happens when a hurricane makes landfall on the Earth. However, the Red Spot does change its shape, size, and color, sometimes dramatically. Such changes are demonstrated in high-resolution Wide Field and Planetary Cameras 1 & 2 images of Jupiter obtained by NASA's Hubble Space Telescope, and presented here by the Hubble Heritage Project team. The mosaic presents a series of pictures of the Red Spot obtained by Hubble between 1992 and 1999 (see PIA01594 thru PIA01599 and PIA02400 thru PIA02402 for individual images).

    Astronomers study weather phenomena on other planets in order to gain a greater understanding of our own Earth's climate. Lacking a solid surface, Jupiter provides us with a laboratory experiment for observing weather phenomena under very different conditions than those prevailing on Earth. This knowledge can also be applied to places in the Earth's atmosphere that are over deep oceans, making them more similar to Jupiter's deep atmosphere.

  6. Jupiter Fractal Art

    NASA Image and Video Library

    2017-08-10

    See Jupiter's Great Red Spot as you've never seen it before in this new Jovian work of art. Artist Mik Petter created this unique, digital artwork using data from the JunoCam imager on NASA's Juno spacecraft. The art form, known as fractals, uses mathematical formulas to create art with an infinite variety of form, detail, color and light. The tumultuous atmospheric zones in and around the Great Red Spot are highlighted by the author's use of colorful fractals. Vibrant colors of various tints and hues, combined with the almost organic-seeming shapes, make this image seem to be a colorized and crowded petri dish of microorganisms, or a close-up view of microscopic and wildly-painted seashells. The original JunoCam image was taken on July 10, 2017 at 7:10 p.m. PDT (10:10 p.m. EDT), as the Juno spacecraft performed its seventh close flyby of Jupiter. The spacecraft captured the image from about 8,648 miles (13,917 kilometers) above the tops of the clouds of the planet at a latitude of -32.6 degrees. https://photojournal.jpl.nasa.gov/catalog/PIA21777

  7. Jupiter G Impact Evolution

    NASA Technical Reports Server (NTRS)

    1995-01-01

    This mosaic of WFPC-2 images shows the evolution of the Shoemaker-Levy 9 G impact site on Jupiter. The images from lower left to upper right show: the impact plume at 07/18/94 07:38 UT (about 5 minutes after the impact); the fresh impact site at 07/18/94 at 09:19 UT (1.5 hours after impact); the impact site after evolution by the winds of Jupiter (left), along with the L impact (right), taken on 07/21/94 at 6:22 UT (3 days after the G impact and 1.3 days after the L impact); and further evolution of the G and L sites due to winds and an additional impact (S) in the G vicinity, taken on 07/23/94 at 08:08 UT (5 days after the G impact).

    This image and other images and data received from the Hubble Space Telescope are posted on the World Wide Web on the Space Telescope Science Institute home page at URL http://oposite.stsci.edu/pubinfo/

  8. Loops of Jupiter

    NASA Astrophysics Data System (ADS)

    Opolski, Antoni

    2014-12-01

    Professor Antoni Opolski was actively interested in astronomy after his retirement in 1983. He especially liked to study the works of the famous astronomer Copernicus getting inspiration for his own work. Opolski started his work on planetary loops in 2011 continuing it to the end of 2012 . During this period calculations, drawings, tables, and basic descriptions of all the planets of the Solar System were created with the use of a piece of paper and a pencil only. In 2011 Antoni Opolski asked us to help him in editing the manuscript and preparing it for publication. We have been honored having the opportunity to work on articles on planetary loops with Antoni Opolski in his house for several months. In the middle of 2012 the detailed material on Jupiter was ready. However, professor Opolski improved the article by smoothing the text and preparing new, better drawings. Finally the article ''Loops of Jupiter'', written by the 99- year old astronomer, was published in the year of his 100th birthday.

  9. Secular orbital evolution of Jupiter family comets

    NASA Astrophysics Data System (ADS)

    Rickman, H.; Gabryszewski, R.; Wajer, P.; Wiśniowski, T.; Wójcikowski, K.; Szutowicz, S.; Valsecchi, G. B.; Morbidelli, A.

    2017-02-01

    Context. The issue of the long term dynamics of Jupiter family comets (JFCs) involves uncertain assumptions about the physical evolution and lifetimes of these comets. Contrary to what is often assumed, real effects of secular dynamics cannot be excluded and therefore merit investigation. Aims: We use a random sample of late heavy bombardment cometary projectiles to study the long-term dynamics of JFCs by a Monte Carlo approach. In a steady-state picture of the Jupiter family, we investigate the orbital distribution of JFCs, including rarely visited domains like retrograde orbits or orbits within the outer parts of the asteroid main belt. Methods: We integrate 100 000 objects over a maximum of 100 000 orbital revolutions including the Sun, a comet, and four giant planets. Considering the steady-state number of JFCs to be proportional to the total time spent in the respective orbital domain, we derive the capture rate based on observed JFCs with small perihelia and large nuclei. We consider a purely dynamical model and one where the nuclei are eroded by ice sublimation. Results: The JFC inclination distribution is incompatible with our erosional model. This may imply that a new type of comet evolution model is necessary. Considering that comets may live for a long time, we show that JFCs can evolve into retrograde orbits as well as asteroidal orbits in the outer main belt or Cybele regions. The steady-state capture rate into the Jupiter family is consistent with 1 × 109 scattered disk objects with diameters D > 2 km. Conclusions: Our excited scattered disk makes it difficult to explain the JFC inclination distribution, unless the physical evolution of JFCs is more intricate than assumed in standard, erosional models. Independent of this, the population size of the Jupiter family is consistent with a relatively low-mass scattered disk.

  10. Long slit spectropolarimetry of Jupiter and Saturn

    NASA Astrophysics Data System (ADS)

    Schmid, H. M.; Joos, F.; Buenzli, E.; Gisler, D.

    2011-04-01

    We present ground-based limb polarization measurements of Jupiter and Saturn consisting of full disk imaging polarimetry for the wavelength 7300 Å and spatially resolved (long-slit) spectropolarimetry covering the wavelength range 5200-9350 Å. For the polar region of Jupiter we find for λ = 6000 Å a very strong radial (perpendicular to the limb) fractional polarization with a seeing corrected maximum of about +11.5% in the South and +10.0% in the North. This indicates that the polarizing haze layer is thicker at the South pole. The polar haze layers extend down to 58° in latitude. The derived polarization values are much higher than reported in previous studies because of the better spatial resolution of our data and an appropriate consideration of the atmospheric seeing. Model calculations demonstrate that the high limb polarization can be explained by strongly polarizing ( p ≈ 1.0), high albedo ( ω ≈ 0.98) haze particles with a scattering asymmetry parameter of g ≈ 0.6 as expected for aggregate particles of the type described by West and Smith (West, R.A., Smith, P.H. [1991]. Icarus 90, 330-333). The deduced particle parameters are distinctively different when compared to lower latitude regions. The spectropolarimetry of Jupiter shows a decrease in the polar limb polarization towards longer wavelengths and a significantly enhanced polarization in strong methane bands when compared to the adjacent continuum. This is a natural outcome for a highly polarizing haze layer above an atmosphere where multiple scatterings are suppressed in absorption bands. For lower latitudes the fractional polarization is small, negative, and it depends only little on wavelength except for the strong CH 4-band at 8870 Å. The South pole of Saturn shows a lower polarization ( p ≈ 1.0-1.5%) than the poles of Jupiter. The spectropolarimetric signal for Saturn decrease rapidly with wavelength and shows no significant enhancements in the fractional polarization in the

  11. Jupiter's Moons: Family Portrait

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This montage shows the best views of Jupiter's four large and diverse 'Galilean' satellites as seen by the Long Range Reconnaissance Imager (LORRI) on the New Horizons spacecraft during its flyby of Jupiter in late February 2007. The four moons are, from left to right: Io, Europa, Ganymede and Callisto. The images have been scaled to represent the true relative sizes of the four moons and are arranged in their order from Jupiter.

    Io, 3,640 kilometers (2,260 miles) in diameter, was imaged at 03:50 Universal Time on February 28 from a range of 2.7 million kilometers (1.7 million miles). The original image scale was 13 kilometers per pixel, and the image is centered at Io coordinates 6 degrees south, 22 degrees west. Io is notable for its active volcanism, which New Horizons has studied extensively.

    Europa, 3,120 kilometers (1,938 miles) in diameter, was imaged at 01:28 Universal Time on February 28 from a range of 3 million kilometers (1.8 million miles). The original image scale was 15 kilometers per pixel, and the image is centered at Europa coordinates 6 degrees south, 347 degrees west. Europa's smooth, icy surface likely conceals an ocean of liquid water. New Horizons obtained data on Europa's surface composition and imaged subtle surface features, and analysis of these data may provide new information about the ocean and the icy shell that covers it.

    New Horizons spied Ganymede, 5,262 kilometers (3,268 miles) in diameter, at 10:01 Universal Time on February 27 from 3.5 million kilometers (2.2 million miles) away. The original scale was 17 kilometers per pixel, and the image is centered at Ganymede coordinates 6 degrees south, 38 degrees west. Ganymede, the largest moon in the solar system, has a dirty ice surface cut by fractures and peppered by impact craters. New Horizons' infrared observations may provide insight into the composition of the moon's surface and interior.

    Callisto, 4,820 kilometers (2,995 miles) in diameter, was imaged

  12. Jupiter Stratospheric Haze Comparison

    NASA Technical Reports Server (NTRS)

    1996-01-01

    These two views of Jupiter obtained by the imaging system aboard the Galileo spacecraft show evidence of strikingly different stratospheric hazes between the polar regions and low or mid latitudes. The Great Red Spot shows in one mosaic, centered at about 20 degrees South latitude and taken on June 26, 1996 at a range of 1.46 million kilometers. The other mosaic is centered near 50 degrees North latitude, and was taken on November 4, 1996 at a range of 1.60 million kilometers.

    North is at the top in both images. In the Red Spot image, the edge of the planet (limb) runs in a single arc from lower left to upper right, with dark space at lower right. In the polar image, the limb runs in two segments across the top right corner, with dark space at top right. Both images are mosaics; the offset of the individual frames of the mosaic produces the jagged border and the break in the polar limb.

    These are false color images, constructed specifically to reveal cloud elevation differences. Three color channels are used. The red channel is an image taken at a near infrared wavelength where methane in Jupiter's atmosphere is strongly absorbing, and therefore gives no information about deep clouds but reveals high clouds. The green channel is a weaker methane band, and the blue channel is assigned to a wavelength where Jupiter's atmosphere is transparent. Thus red features indicate high hazes. A view near the edge of the planet accentuates the high hazes because of the slanting path of the line of sight.

    The pronounced reddening near the edge of the planet in polar regions indicates a high stratospheric haze. Comparison with the Great Red Spot shows that such a high haze is absent at that latitude. Detailed analysis shows that a stratospheric haze exists at both latitudes but is approximately 50 km higher near the poles. It is likely that the high polar haze is produced by magnetospheric particles, which travel along magnetic field lines and bombard the upper atmosphere

  13. SECULAR CHAOS AND THE PRODUCTION OF HOT JUPITERS

    SciTech Connect

    Wu Yanqin; Lithwick, Yoram

    2011-07-10

    In a planetary system with two or more well-spaced, eccentric, inclined planets, secular interactions may lead to chaos. The innermost planet may gradually become very eccentric and/or inclined as a result of the secular degrees of freedom drifting toward equipartition of angular momentum deficit. Secular chaos is known to be responsible for the eventual destabilization of Mercury in our own solar system. Here we focus on systems with three giant planets. We characterize the secular chaos and demonstrate the criterion for it to occur, but leave a detailed understanding of secular chaos to a companion paper. After an extended period of eccentricity diffusion, the inner planet's pericenter can approach the star to within a few stellar radii. Strong tidal interactions and ensuing tidal dissipation extract orbital energy from the planet and pull it inward, creating a hot Jupiter. In contrast to other proposed channels for the production of hot Jupiters, such a scenario (which we term 'secular migration') explains a range of observations: the pile-up of hot Jupiters at 3 day orbital periods, the fact that hot Jupiters are in general less massive than other radial velocity planets, that they may have misaligned inclinations with respect to stellar spin, and that they have few easily detectable companions (but may have giant companions in distant orbits). Secular migration can also explain close-in planets as low in mass as Neptune; and an aborted secular migration can explain the 'warm Jupiters' at intermediate distances. In addition, the frequency of hot Jupiters formed via secular migration increases with stellar age. We further suggest that secular chaos may be responsible for the observed eccentricities of giant planets at larger distances and that these planets could exhibit significant spin-orbit misalignment.

  14. Secular Chaos and the Production of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Wu, Yanqin; Lithwick, Yoram

    2011-07-01

    In a planetary system with two or more well-spaced, eccentric, inclined planets, secular interactions may lead to chaos. The innermost planet may gradually become very eccentric and/or inclined as a result of the secular degrees of freedom drifting toward equipartition of angular momentum deficit. Secular chaos is known to be responsible for the eventual destabilization of Mercury in our own solar system. Here we focus on systems with three giant planets. We characterize the secular chaos and demonstrate the criterion for it to occur, but leave a detailed understanding of secular chaos to a companion paper. After an extended period of eccentricity diffusion, the inner planet's pericenter can approach the star to within a few stellar radii. Strong tidal interactions and ensuing tidal dissipation extract orbital energy from the planet and pull it inward, creating a hot Jupiter. In contrast to other proposed channels for the production of hot Jupiters, such a scenario (which we term "secular migration") explains a range of observations: the pile-up of hot Jupiters at 3 day orbital periods, the fact that hot Jupiters are in general less massive than other radial velocity planets, that they may have misaligned inclinations with respect to stellar spin, and that they have few easily detectable companions (but may have giant companions in distant orbits). Secular migration can also explain close-in planets as low in mass as Neptune; and an aborted secular migration can explain the "warm Jupiters" at intermediate distances. In addition, the frequency of hot Jupiters formed via secular migration increases with stellar age. We further suggest that secular chaos may be responsible for the observed eccentricities of giant planets at larger distances and that these planets could exhibit significant spin-orbit misalignment.

  15. Soaring Over Jupiter

    NASA Image and Video Library

    2017-09-21

    This striking image of Jupiter was captured by NASA's Juno spacecraft as it performed its eighth flyby of the gas giant planet. The image was taken on Sept. 1, 2017 at 2:58 p.m. PDT (5:58 p.m. EDT). At the time the image was taken, the spacecraft was 4,707 miles (7,576 kilometers) from the tops of the clouds of the planet at a latitude of about -17.4 degrees. Citizen scientist Gerald Eichstädt processed this image using data from the JunoCam imager. Points of interest are "Whale's Tail" and "Dan's Spot." https://photojournal.jpl.nasa.gov/catalog/PIA21966

  16. Lightning activity on Jupiter

    NASA Technical Reports Server (NTRS)

    Borucki, W. J.; Bar-Nun, A.; Scarf, F. L.; Look, A. F.; Hunt, G. E.

    1982-01-01

    Photographic observations of the nightside of Jupiter by the Voyager 1 spacecraft show the presence of extensive lightning activity. Detection of whistlers by the plasma wave analyzer confirms the optical observations and implies that many flashes were not recorded by the Voyager camera because the intensity of the flashes was below the threshold sensitivity of the camera. Measurements of the optical energy radiated per flash indicate that the observed flashes had energies similar to that for terrestrial superbolts. The best estimate of the lightning energy dissipation rate of 0.0004 W/sq m was derived from a consideration of the optical and radiofrequency measurements. The ratio of the energy dissipated by lightning compared to the convective energy flux is estimated to be between 0.000027 and 0.00005. The terrestrial value is 0.0001.

  17. Northern Belt of Jupiter

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    A four-panel frame shows a section of Jupiter's north equatorial belt viewed by NASA's Cassini spacecraft at four different wavelengths, and a separate reference frame shows the location of the belt on the planet.

    A fascinating aspect of the images in the four-panel frame is the small bright spot in the center of each. The images come from different layers of the atmosphere, so the spot appears to be a storm penetrating upward through several layers. This may in fact be a 'monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. These images were taken on Nov. 27, 2000, at a resolution of 192 kilometers (119 miles) per pixel. They have been contrast-enhanced to highlight features in the atmosphere.

    The top panel of the four-panel frame is an image taken in a near-infrared wavelength at which the gases in Jupiter's atmosphere are relatively non-absorbing. Sunlight can penetrate deeply into the atmosphere at this wavelength and be reflected back out, providing a view of an underlying region of the atmosphere, the lower troposphere.

    The second panel was taken in the blue portion of wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the top panel.

    The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. Dark places are regions without high-level clouds and consequently large amounts of methane accessible to sunlight. Bright regions are locations with high clouds in the upper troposphere shielding the methane below.

    The bottom panel was taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and hazes in the stratosphere, above the troposphere

  18. Northern Belt of Jupiter

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site]

    A four-panel frame shows a section of Jupiter's north equatorial belt viewed by NASA's Cassini spacecraft at four different wavelengths, and a separate reference frame shows the location of the belt on the planet.

    A fascinating aspect of the images in the four-panel frame is the small bright spot in the center of each. The images come from different layers of the atmosphere, so the spot appears to be a storm penetrating upward through several layers. This may in fact be a 'monster' thunderstorm, penetrating all the way into the stratosphere, as do some summer thunderstorms in the midwestern United States. These images were taken on Nov. 27, 2000, at a resolution of 192 kilometers (119 miles) per pixel. They have been contrast-enhanced to highlight features in the atmosphere.

    The top panel of the four-panel frame is an image taken in a near-infrared wavelength at which the gases in Jupiter's atmosphere are relatively non-absorbing. Sunlight can penetrate deeply into the atmosphere at this wavelength and be reflected back out, providing a view of an underlying region of the atmosphere, the lower troposphere.

    The second panel was taken in the blue portion of wavelengths detected by the human eye. At these wavelengths, gases in the atmosphere scatter a modest amount of sunlight, so the clouds we see tend to be at somewhat higher altitudes than in the top panel.

    The third panel shows near-infrared reflected sunlight at a wavelength where the gas methane, an important constituent of Jupiter's atmosphere, absorbs strongly. Dark places are regions without high-level clouds and consequently large amounts of methane accessible to sunlight. Bright regions are locations with high clouds in the upper troposphere shielding the methane below.

    The bottom panel was taken in the ultraviolet. At these very short wavelengths, the clear atmosphere scatters sunlight, and hazes in the stratosphere, above the troposphere

  19. Jupiter and the Voyager mission

    USGS Publications Warehouse

    Soderblom, L.; Spall, Henry

    1980-01-01

    In 1977, the United States launched two unmanned Voyager spacecraft that were to take part in an extensive reconnaissance of the outer planets over a 12-year period visiting the environs of Jupiter, Saturn, Uranus, and Neptune. Their first encounter was with the complex Jupiter planetary system 400 million miles away. Sweeping by Jupiter and its five moons in 1979, the two spacecraft have sent back to Earth an enormous amount of data that will prove to be vital in understanding our solar system. Voyager 1 is scheduled to fly past Saturn on November 13 of this year; Voyager 2, in August of the following year. 

  20. Jupiter Clouds in Depth

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nm

    Images from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.

    Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.

    The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.

    The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter

  1. Constraining Planetary Migration Mechanisms with Highly Eccentric Hot Jupiter Progenitors

    NASA Astrophysics Data System (ADS)

    Dawson, Rebekah I.; Johnson, J. A.; Murray-Clay, R.; Morton, T.; Crepp, J. R.; Fabrycky, D. C.; Howard, A.

    2013-01-01

    Abstract: Hot Jupiters --- Jupiter-mass planets orbiting within 0.1 AU of their host stars --- are unlikely to have formed in situ and thus serve as evidence for the prevalence of planetary migration. However, it is debated whether the typical hot Jupiter migrated smoothly inward through the protoplanetary disk or was perturbed onto an eccentric orbit, which tidal dissipation subsequently shrank and circularized during close passages to the star. In the latter class of model, the perturber may be a stellar or planetary companion, which causes the Jupiter to undergo a temporary epoch with high eccentricity (e> 0.9). Socrates and et al. (2012) predicted that these super-eccentric hot Jupiter progenitors should be readily discoverable through the transit method by the Kepler Mission. However, eccentricities of individual transiting planets primarily come from Doppler measurements, which are unfortunately precluded by the faintness of most Kepler targets. To solve this problem, we developed a Bayesian method (the “photoeccentric effect”) for measuring an individual planet's eccentricity solely from its Kepler light curve, allowing for a tight measurement of large eccentricities. We applied this new approach to the Kepler giant planet candidates and identified KOI-1474.01 as an eccentric planet (e = 0.81+0.10/-0.07) with an average orbital period of 69.7340 days, varying by approximately 1 hour due to perturbations by a massive outer companion, which is possibly the culprit responsible for KOI-1474.01’s highly eccentric orbit. KOI-1474.01 is likely a failed hot Jupiter, too far from its host star to be tidally transformed into a hot Jupiter. We found a significant lack of super-eccentric proto-hot Jupiters compared to the number expected, allowing us to place a strong upper limit on the fraction of hot Jupiters created by stellar binaries. Our results are consistent with disks or planetary companions being the primary channel for hot Jupiter creation. Supported by

  2. Juno Listens to Jupiters Auroras

    NASA Image and Video Library

    2016-09-01

    During Juno's close flyby of Jupiter on August 27, 2016, the Waves instrument received radio signals associated with the giant planet's intense auroras. Animation and audio display the signals after they have been shifted into the audio frequency range.

  3. Dark Matter Hairs Around Jupiter

    NASA Image and Video Library

    2015-11-23

    This illustration shows Jupiter surrounded by filaments of dark matter called "hairs," which are proposed in a study in the Astrophysical Journal by Gary Prézeau of NASA's Jet Propulsion Laboratory, Pasadena, California. A hair is created when a stream of dark matter particles goes through the planet. According to simulations, the hair is densest at a point called the "root." When particles of a dark matter stream pass through the core of Jupiter, they form a hair whose root has a particle density about a trillion times greater than average. The size of Jupiter relative to the distance between Jupiter and the hair roots is to scale. http://photojournal.jpl.nasa.gov/catalog/PIA20178

  4. Inertial mode oscillations of Jupiter

    NASA Technical Reports Server (NTRS)

    Lee, Umin; Strohmayer, Tod E.; Van Horn, H. M.

    1992-01-01

    The properties of the inertial modes of Jupiter are investigated using several different models for that planet. The inertial modes are rotationally induced oscillation modes for which the kinetic energy generally dominates the potential energy of oscillation. The frequency spectrum of the inertial modes mainly depends on the density stratification of Jupiter and sensitively reflects the existence or nonexistence of density discontinuities in the interior. A particularly interesting consequence of the calculations is that observations of the inertial oscillations of Jupiter may enable us to determine whether or not the dense hydrogen in the envelope of this planet undergoes the plasma phase transition (PPT). This may provide an astrophysical test of current theories of the thermodynamic properties of dense hydrogen. It is also found that the discontinuity modes associated with the PPT have observable amplitdues at the surface. These modes may provide an independent test of the interior structure of Jupiter.

  5. Jupiter Clouds in Depth

    NASA Technical Reports Server (NTRS)

    2000-01-01

    [figure removed for brevity, see original site] 619 nm [figure removed for brevity, see original site] 727 nm [figure removed for brevity, see original site] 890 nm

    Images from NASA's Cassini spacecraft using three different filters reveal cloud structures and movements at different depths in the atmosphere around Jupiter's south pole.

    Cassini's cameras come equipped with filters that sample three wavelengths where methane gas absorbs light. These are in the red at 619 nanometer (nm) wavelength and in the near-infrared at 727 nm and 890 nm. Absorption in the 619 nm filter is weak. It is stronger in the 727 nm band and very strong in the 890 nm band where 90 percent of the light is absorbed by methane gas. Light in the weakest band can penetrate the deepest into Jupiter's atmosphere. It is sensitive to the amount of cloud and haze down to the pressure of the water cloud, which lies at a depth where pressure is about 6 times the atmospheric pressure at sea level on the Earth). Light in the strongest methane band is absorbed at high altitude and is sensitive only to the ammonia cloud level and higher (pressures less than about one-half of Earth's atmospheric pressure) and the middle methane band is sensitive to the ammonia and ammonium hydrosulfide cloud layers as deep as two times Earth's atmospheric pressure.

    The images shown here demonstrate the power of these filters in studies of cloud stratigraphy. The images cover latitudes from about 15 degrees north at the top down to the southern polar region at the bottom. The left and middle images are ratios, the image in the methane filter divided by the image at a nearby wavelength outside the methane band. Using ratios emphasizes where contrast is due to methane absorption and not to other factors, such as the absorptive properties of the cloud particles, which influence contrast at all wavelengths.

    The most prominent feature seen in all three filters is the polar stratospheric haze that makes Jupiter

  6. Juno First Slice of Jupiter

    NASA Image and Video Library

    2016-10-19

    This composite image depicts Jupiter's cloud formations as seen through the eyes of Juno's Microwave Radiometer (MWR) instrument as compared to the top layer, a Cassini Imaging Science Subsystem image of the planet. The MWR can see a couple of hundred miles (kilometers) into Jupiter's atmosphere with its largest antenna. The belts and bands visible on the surface are also visible in modified form in each layer below. http://photojournal.jpl.nasa.gov/catalog/PIA21107

  7. The Juno Mission to Jupiter

    NASA Technical Reports Server (NTRS)

    Grammier, Richard S.

    2006-01-01

    Origin: Determine O/H ratio (water abundance) and constrain core mass to decide among alternative theories of origin. Interior: Understand Jupiter's interior structure and dynamical properties by mapping its gravitational and magnetic fields Atmosphere: Map variations in atmospheric composition, temperature, cloud opacity and dynamics to depths greater than 100 bars at all latitudes. Magnetosphere: Characterize and explore the three-dimensional structure of Jupiter's polar magnetosphere and auroras.

  8. Transitions in the Cloud Composition of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Parmentier, Vivien; Fortney, Jonathan J.; Showman, Adam P.; Morley, Caroline; Marley, Mark S.

    2016-09-01

    Over a large range of equilibrium temperatures, clouds shape the transmission spectrum of hot Jupiter atmospheres, yet their composition remains unknown. Recent observations show that the Kepler light curves of some hot Jupiters are asymmetric: for the hottest planets, the light curve peaks before secondary eclipse, whereas for planets cooler than ˜1900 K, it peaks after secondary eclipse. We use the thermal structure from 3D global circulation models to determine the expected cloud distribution and Kepler light curves of hot Jupiters. We demonstrate that the change from an optical light curve dominated by thermal emission to one dominated by scattering (reflection) naturally explains the observed trend from negative to positive offset. For the cool planets the presence of an asymmetry in the Kepler light curve is a telltale sign of the cloud composition, because each cloud species can produce an offset only over a narrow range of effective temperatures. By comparing our models and the observations, we show that the cloud composition of hot Jupiters likely varies with equilibrium temperature. We suggest that a transition occurs between silicate and manganese sulfide clouds at a temperature near 1600 K, analogous to the L/T transition on brown dwarfs. The cold trapping of cloud species below the photosphere naturally produces such a transition and predicts similar transitions for other condensates, including TiO. We predict that most hot Jupiters should have cloudy nightsides, that partial cloudiness should be common at the limb, and that the dayside hot spot should often be cloud-free.

  9. Transitions in the cloud composition of hot Jupiters

    NASA Astrophysics Data System (ADS)

    Parmentier, Vivien; Fortney, Jonathan J.; Showman, Adam; Morley, Caroline; Marley, Mark S.

    2016-10-01

    Over a large range of equilibrium temperatures, clouds shape the transmission spectrum of hot Jupiter atmospheres, yet their composition remains unknown. Recent observations show that the Kepler lightcurves of some hot Jupiters are asymmetric: for the hottest planets, the lightcurve peaks before secondary eclipse, whereas for planets cooler than 1900K, it peaks after secondary eclipse. We use the thermal structure from 3D global circulation models to determine the expected cloud distribution and Kepler lightcurves of hot Jupiters. We demonstrate that the change from an optical lightcurve dominated by thermal emission to one dominated by scattering (reflection) naturally explains the observed trend from negative to positive offset. For the cool planets the presence of an asymmetry in the Kepler lightcurve is a telltale sign of the cloud composition, because each cloud species can produce an offset only over a narrow range of effective temperatures. By comparing our models and the observations, we show that the cloud composition of hot Jupiters likely varies with equilibrium temperature. We suggest that a transition occurs between silicate and manganese sulfide clouds at a temperature near 1600K, analogous to the L/T transition on brown dwarfs. The cold trapping of cloud species below the photosphere naturally produces such a transition and predicts similar transitions for other condensates, including TiO. We predict that most hot Jupiters should have cloudy nightsides, that partial cloudiness should be common at the limb and that the dayside hot spot should often be cloud-free.

  10. XMM-Newton X-Ray Observation of Jupiter

    NASA Technical Reports Server (NTRS)

    Waite, J. Hunter

    2005-01-01

    Soft X-ray emission has been observed from the disk of both Jupiter and Saturn as well as from the auroral regions of these planets. The low-latitude disk emission as observed by ROSAT, the Chandra X-Ray Observatory, and XMM-Newton appears to be uniformly distributed across the disk and to be correlated with solar activity. These characteristics suggest that the disk x-rays are produced by: (1) the elastic scattering of solar X-rays by atmospheric neutrals and (2) the absorption of solar X-rays in the carbon K-shell followed by fluorescent emission. The carbon atoms are found in methane molecules located below the homopause. In this paper we present the results of calculations of the scattering albedo for soft x-rays. We also show the calculated x-ray intensity for a range of atmospheric abundances for Jupiter and Saturn and for a number of solar irradiance spectra. The model calculations are compared with recent x-ray observations of Jupiter and Saturn. We conclude that the emission of soft x-rays from the disks of Jupiter and Saturn can be largely explained by the scattering and fluorescence of soft x-rays. We suggest that measured x-ray intensities from the disk regions of Jupiter

  11. Jupiter Eruptions Captured in Infrared

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover

    Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers.

    This infrared image shows two bright plume eruptions obtained by the NASA Infrared Telescope Facility on April 5, 2007.

    Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena.

    According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vigorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  12. Jupiter Eruptions Captured in Infrared

    NASA Technical Reports Server (NTRS)

    2008-01-01

    [figure removed for brevity, see original site] Click on the image for high resolution image of Nature Cover

    Detailed analysis of two continent-sized storms that erupted in Jupiter's atmosphere in March 2007 shows that Jupiter's internal heat plays a significant role in generating atmospheric disturbances. Understanding these outbreaks could be the key to unlock the mysteries buried in the deep Jovian atmosphere, say astronomers.

    This infrared image shows two bright plume eruptions obtained by the NASA Infrared Telescope Facility on April 5, 2007.

    Understanding these phenomena is important for Earth's meteorology where storms are present everywhere and jet streams dominate the atmospheric circulation. Jupiter is a natural laboratory where atmospheric scientists study the nature and interplay of the intense jets and severe atmospheric phenomena.

    According to the analysis, the bright plumes were storm systems triggered in Jupiter's deep water clouds that moved upward in the atmosphere vigorously and injected a fresh mixture of ammonia ice and water about 20 miles (30 kilometers) above the visible clouds. The storms moved in the peak of a jet stream in Jupiter's atmosphere at 375 miles per hour (600 kilometers per hour). Models of the disturbance indicate that the jet stream extends deep in the buried atmosphere of Jupiter, more than 60 miles (approximately100 kilometers) below the cloud tops where most sunlight is absorbed.

  13. Ulysses dust measurements near Jupiter.

    PubMed

    Grün, E; Zook, H A; Baguhl, M; Fechtig, H; Hanner, M S; Kissel, J; Lindblad, B A; Linkert, D; Linkert, G; Mann, I B

    1992-09-11

    Submicrometer- to micrometer-sized particles were recorded by the Ulysses dust detector within 40 days of the Jupiter flyby. Nine impacts were recorded within 50 Jupiter radii with most of them recorded after closest approach. Three of these impacts are consistent with particles on prograde orbits around Jupiter and the rest are believed to have resulted from gravitationally focused interplanetary dust. From the ratio of the impact rate before the Jupiter flyby to the impact rate after the Jupiter flyby it is concluded that interplanetary dust particles at the distance of Jupiter move on mostly retrograde orbits. On 10 March 1992, Ulysses passed through an intense dust stream. The dust detector recorded 126 impacts within 26 hours. The stream particles were moving on highly inclined and apparently hyperbolic orbits with perihelion distances of >5 astronomical units. Interplanetary dust is lost rather quickly from the solar system through collisions and other mechanisms and must be almost continuously replenished to maintain observed abundances. Dust flux measurements, therefore, give evidence of the recent rates of production from sources such as comets, asteroids, and moons, as well as the possible presence of interstellar grains.

  14. Ulysses dust measurements near Jupiter

    NASA Technical Reports Server (NTRS)

    Gruen, Eberhard; Zook, Herbert A.; Baguhl, Michael; Fechtig, Hugo; Hanner, Martha S.; Kissel, Jochen; Lindblad, Bertil A.; Linkert, Dietmar; Linkert, Gudrun; Mann, Ingrid B.

    1992-01-01

    Submicrometer- to micrometer-sized particles were recorded by the Ulysses dust detector within 40 days of the Jupiter flyby. Nine impacts were recorded within 50 Jupiter radii with most of them recorded after closest approach. Three of these impacts are consistent with particles on prograde orbits around Jupiter and the rest are believed to have resulted from gravitationally focused interplanetary dust. From the ratio of the impact rate before the Jupiter flyby to the impact rate after the Jupiter flyby it is concluded that interplanetary dust particles at the distance of Jupiter move on mostly retrograde orbits. On 10 March 1992, Ulysses passed through an intense dust stream. The dust detector recorded 126 impacts within 26 hours. The stream particles were moving on highly inclined and apparently hyperbolic orbits with perihelion distances of greater than 5 astronomical units. Interplanetary dust is lost rather quickly from the solar system through collisions and other mechanisms and must be almost continuously replenished to maintain observed abundances. Dust flux measurements, therefore, give evidence of the recent rates of production from sources such as comets, asteroids, and moons, as well as the possible presence of interstellar grains.

  15. Japanese mission plan for Jupiter system: The Jupiter magnetospheric orbiter and the Trojan asteroid explorer

    NASA Astrophysics Data System (ADS)

    Sasaki, S.; Fujimoto, M.; Yano, H.; Takashima, T.; Kasaba, Y.; Takahashi, Y.; Kimura, J.; Funase, R.; Mori, O.; Tsuda, Y.; Campagnola, S.; Kawakatsu, Y.

    2011-10-01

    In the future Jupiter system study, Coordinated observation of Jovian magnetosphere is one of the important targets of the mission in addition to icy satellites, atmosphere, and interior of Jupiter. JAXA will take a role on the magnetosphere spinner JMO (Jupiter Magnetospheric Orbiter), in addition to JGO (Jupiter Ganymede Orbiter) by ESA and JEO (Jupiter Europa Orbiter) by NASA. We will combine JMO with a proposed solar sail mission of JAXA for Jupiter and one of Trojan asteroids. Since Trojan asteroids could be representing raw solid materials of Jupiter or at least outer solar system bodies, involvement of Trojan observation should enhance the quality of Jupiter system exploration.

  16. Jupiter's Great Red Spot and other vortices

    NASA Technical Reports Server (NTRS)

    Marcus, Philip S.

    1993-01-01

    A theoretical explanation of Jupiter's Great Red Spot (GRS) as the self-organization of vorticity in turbulence is presented. A number of properties of the GRS and other Jovian vortices that are unambiguous from the data are listed. The simplest possible model that explains these properties one at a time rather than in a difficult all-encompassing planetary global circulation model is presented. It is shown that Jovian vortices reflect the behavior of quasi-geostrophic (QG) vortices embedded in an east-west wind with bands of uniform potential vorticity. It is argued that most of the properties of the Jovian vortices can be easily explained and understood with QG theory. Many of the signatures of QG vortices are apparent on Voyager images. In numerical and laboratory experiments, QG vortices relax to approximately steady states like the Jovian vortices, rather than oscillating or rotating Kida ellipses.

  17. The dusty ballerina skirt of Jupiter

    NASA Astrophysics Data System (ADS)

    Horanyi, M.; Morfill, G.; Gruen, E.

    1993-12-01

    We suggest a model to explain the unexpected recurrent dust events that were observed during the Jupiter encounter by the dust detector on board the Ulysses spacecraft. This model is based dust-magnetosphere interactions. Dust particles inside the Jovian magnetosphere collect electrostatic charges and their interaction with the magnetic and electric fields can lead to energization and subsequent ejection. We discuss the dusty regions (ring/halo, `gossamer' ring) and also Io as potential sources for the Ulysses events. This model favors Io as a source. The mass and velocity range of the escaping particles are compatible with the observations, and we also suggest internal periodicities to explain the recurrent nature of the Ulysses dust events.

  18. The dusty ballerina skirt of Jupiter

    NASA Technical Reports Server (NTRS)

    Horanyi, M.; Morfill, G.; Gruen, E.

    1993-01-01

    We suggest a model to explain the unexpected recurrent dust events that were observed during the Jupiter encounter by the dust detector on board the Ulysses spacecraft. This model is based dust-magnetosphere interactions. Dust particles inside the Jovian magnetosphere collect electrostatic charges and their interaction with the magnetic and electric fields can lead to energization and subsequent ejection. We discuss the dusty regions (ring/halo, `gossamer' ring) and also Io as potential sources for the Ulysses events. This model favors Io as a source. The mass and velocity range of the escaping particles are compatible with the observations, and we also suggest internal periodicities to explain the recurrent nature of the Ulysses dust events.

  19. Jupiter's moon Io

    NASA Technical Reports Server (NTRS)

    1979-01-01

    This picture shows a special color reconstruction of one of the erupting volcanos on Io discovered by Voyager 1 during its encounter with Jupiter on the 4th and 5th of March. The picture was taken March 4 about 5:00 p.m. from a range of about half a million kilometers showing an eruption region on the horizon. This method of color analysis allows scientists to combine data from four pictures, taken in ultraviolet, blue, green and orange light. In this picture one can see the strong change in color of the erupting plume. The region that is brighter in ultraviolet light (blue in this image) is much more extensive than the denser, bright yellow region near the center of the eruption. Scientists will use data of this type to study the amount of gas and dust in the eruption and the size of dust particles. Preliminary analysis suggests that the bright ultraviolet part of the cloud may be due to scattered light from very fine particles (the same effect which makes smoke appear bluish).

  20. Jupiter Infrared Glow

    NASA Image and Video Library

    2015-07-07

    This still from an animation of four images shows Jupiter in infrared light as seen by NASA InfraRed Telescope Facility, or IRTF, on May 16, 2015. The observations were obtained in support of NASA's Juno mission by a team headed by Juno scientist Glenn Orton. Observations like these are helping to provide spatial and temporal context for what the science instruments on board Juno will see once the spacecraft arrives at the giant planet in mid-2016. Juno will pass very close to the planet -- coming within just a few thousand miles (or kilometers) of the cloud tops every two weeks. That up-close vantage point will be balanced by distant views of the planet that show how different features move and change over time in relation to each other. The IRTF is a three-meter telescope, optimized for infrared observations, and located at the summit of Mauna Kea, Hawaii. The observatory is operated and managed for NASA by the University of Hawaii Institute for Astronomy, Honolulu. http://photojournal.jpl.nasa.gov/catalog/PIA19640

  1. Zonal Flow and Vortices in Anelastic Deep Convection Models of Jupiter and Saturn With Shallow Stable Stratification

    NASA Astrophysics Data System (ADS)

    Heimpel, M. H.; Wicht, J.; Gastine, T.

    2015-12-01

    Planetary jet streams and vortices have been studied for over 350 years, yet their origin and dynamics are still vigorously debated. On both Jupiter and Saturn zonal flow consists of equatorial superrotation and alternating East-West jets at higher latitude. On Jupiter, numerous vortices, the vast majority anticyclones, occur with various sizes and lifetimes, interacting strongly with the zonal flow. Saturn's vortices and jets are also clearly coupled, and its North and South polar vortices are cyclonic. Models of giant planet atmospheres have generally been of two classes. Shallow flow models produce jets and vortices from 2D turbulence in a very thin spherical layer, but require special conditions to reproduce observed equatorial superrotation. In contrast, deep convection models generically reproduce equatorial superrotation, but typically lack coherent vortices, which do not survive the formation of jets. Here, we combine elements of both approaches using a 3D spherical shell compressible fluid numerical model, driven by convection at depth, but grading to a stably stratified shallow layer. In typical model simulations convective plumes rising from the deep interior impinge on the stably stratified layer, diverge near the outer spherical surface, and efficiently create the dominant anticyclones, which are shielded by downwelling cyclonic rings and filaments. These results may explain the dominance of anticyclones and the flow structure of small and medium sized anticyclonic ovals on Jupiter. The largest of our model vortices form in westward anticyclonic shear nearest the equatorial jet, similar to Saturn's "storm alley" and Jupiter's Great Red Spot. We also explore conditions under which cyclones, including polar cyclones like those on Saturn, may form.

  2. Time Series of Jupiter Aurora

    NASA Image and Video Library

    1998-06-10

    These mosaics of Jupiter's night side show the Jovian aurora at approximately 45 minute intervals as the auroral ring rotated with the planet below the spacecraft. The images were obtained by the Solid State Imaging (SSI) system on NASA's Galileo spacecraft. during its eleventh orbit of Jupiter. The auroral ring is offset from Jupiter's pole of rotation and reaches the lowest latitude near 165 degrees west longitude. The aurora is hundreds of kilometers wide, and when it crosses the edge of Jupiter, it is about 250 kilometers above the planet. As on Earth, the auroral emission is caused by electrically charged particles striking atoms in the upper atmosphere from above. The particles travel along Jupiter's magnetic field lines, but their origin is not fully understood. The field lines where the aurora is most intense cross the Jovian equator at large distances (many Jovian radii) from the planet. The faint background throughout the image is scattered light in the camera. This stray light comes from the sunlit portion of Jupiter, which is out of the image. In multispectral observations the aurora appears red, consistent with how atomic hydrogen in Jupiter's atmosphere would glow. Galileo's unique perspective allows it to view the night side of the planet at short range, revealing details that cannot be seen from Earth. These detailed features are time dependent, and can be followed in this sequence of Galileo images. In the first mosaic, the auroral ring is directly over Jupiter's limb and is seen "edge on." In the fifth mosaic, the auroral emission is coming from several distinct bands. This mosaic also shows the footprint of the Io flux tube. Volcanic eruptions on Jupiter's moon, Io, spew forth particles that become ionized and are pulled into Jupiter's magnetic field to form an invisible tube, the Io flux tube, between Jupiter and Io. The bright circular feature towards the lower right may mark the location where these energetic particles impact Jupiter. Stars

  3. Hubble Images Reveal Jupiter's Auroras

    NASA Technical Reports Server (NTRS)

    1996-01-01

    These images, taken by the Hubble Space Telescope, reveal changes in Jupiter's auroral emissions and how small auroral spots just outside the emission rings are linked to the planet's volcanic moon, Io. The images represent the most sensitive and sharply-detailed views ever taken of Jovian auroras.

    The top panel pinpoints the effects of emissions from Io, which is about the size of Earth's moon. The black-and-white image on the left, taken in visible light, shows how Io and Jupiter are linked by an invisible electrical current of charged particles called a 'flux tube.' The particles - ejected from Io (the bright spot on Jupiter's right) by volcanic eruptions - flow along Jupiter's magnetic field lines, which thread through Io, to the planet's north and south magnetic poles. This image also shows the belts of clouds surrounding Jupiter as well as the Great Red Spot.

    The black-and-white image on the right, taken in ultraviolet light about 15 minutes later, shows Jupiter's auroral emissions at the north and south poles. Just outside these emissions are the auroral spots. Called 'footprints,' the spots are created when the particles in Io's 'flux tube' reach Jupiter's upper atmosphere and interact with hydrogen gas, making it fluoresce. In this image, Io is not observable because it is faint in the ultraviolet.

    The two ultraviolet images at the bottom of the picture show how the auroral emissions change in brightness and structure as Jupiter rotates. These false-color images also reveal how the magnetic field is offset from Jupiter's spin axis by 10 to 15 degrees. In the right image, the north auroral emission is rising over the left limb; the south auroral oval is beginning to set. The image on the left, obtained on a different date, shows a full view of the north aurora, with a strong emission inside the main auroral oval.

    The images were taken by the telescope's Wide Field and Planetary Camera 2 between May 1994 and September 1995.

    This image and

  4. On Approach: Jupiter and Io

    NASA Technical Reports Server (NTRS)

    2007-01-01

    [figure removed for brevity, see original site] Click on the image for movie of On Approach: Jupiter and Io

    This sequence of images was taken on Jan. 8, 2007, with the New Horizons Long Range Reconnaissance Imager (LORRI), while the spacecraft was about 81 million kilometers (about 50 million miles) from Jupiter. Jupiter's volcanic moon Io is to the right; the planet's Great Red Spot is also visible. The image was one of 11 taken during the Jan. 8 approach sequence, which signaled the opening of the New Horizons Jupiter encounter.

    Even in these early approach images, Jupiter shows different face than what previous visiting spacecraft -- such as Voyager 1, Galileo and Cassini -- have seen. Regions around the equator and in the southern tropical latitudes seem remarkably calm, even in the typically turbulent 'wake' behind the Great Red Spot.

    The New Horizons science team will scrutinize these major meteorological features -- including the unexpectedly calm regions -- to understand the diverse variety of dynamical processes on the solar system's largest planet. These include the newly formed Little Red Spot, the Great Red Spot and a variety of zonal features.

  5. An auroral flare at Jupiter.

    PubMed

    Waite, J H; Gladstone, G R; Lewis, W S; Goldstein, R; McComas, D J; Riley, P; Walker, R J; Robertson, P; Desai, S; Clarke, J T; Young, D T

    2001-04-12

    Jupiter's aurora is the most powerful in the Solar System. It is powered largely by energy extracted from planetary rotation, although there seems also to be a contribution from the solar wind. This contrasts with Earth's aurora, which is generated through the interaction of the solar wind with the magnetosphere. The major features of Jupiter's aurora (based on far-ultraviolet, near-infrared and visible-wavelength observations) include a main oval that generally corotates with the planet and a region of patchy, diffuse emission inside the oval on Jupiter's dusk side. Here we report the discovery of a rapidly evolving, very bright and localized emission poleward of the northern main oval, in a region connected magnetically to Jupiter's outer magnetosphere. The intensity of the emission increased by a factor of 30 within 70 s, and then decreased on a similar timescale, all captured during a single four-minute exposure. This type of flaring emission has not previously been reported for Jupiter (similar, but smaller, transient events have been observed at Earth), and it may be related directly to changes in the solar wind.

  6. Types of Hot Jupiter Atmospheres

    NASA Astrophysics Data System (ADS)

    Bisikalo, Dmitry V.; Kaygorodov, Pavel V.; Ionov, Dmitry E.; Shematovich, Valery I.

    Hot Jupiters, i.e. exoplanet gas giants, having masses comparable to the mass of Jupiter and semimajor axes shorter than 0.1 AU, are a unique class of objects. Since they are so close to the host stars, their atmospheres form and evolve under the action of very active gas dynamical processes caused by the gravitational field and irradiation of the host star. As a matter of fact, the atmospheres of several of these planets fill their Roche lobes , which results in a powerful outflow of material from the planet towards the host star. The energy budget of this process is so important that it almost solely governs the evolution of hot Jupiters gaseous envelopes. Based on the years of experience in the simulations of gas dynamics in mass-exchanging close binary stars, we have investigated specific features of hot Jupiters atmospheres. The analytical estimates and results of 3D numerical simulations, discussed in this Chapter, show that the gaseous envelopes around hot Jupiters may be significantly non-spherical and, at the same time, stationary and long-lived. These results are of fundamental importance for the interpretation of observational data.

  7. Host to Hot Jupiter

    NASA Image and Video Library

    2009-04-16

    This image zooms into a small portion of NASA Kepler full field of view -- an expansive, 100-square-degree patch of sky in our Milky Way galaxy. At the center of the field is a star with a known "hot Jupiter" planet, named "TrES-2," zipping closely around it every 2.5 days. Kepler will observe TrES-2 and other known planets as a test to demonstrate that it is working properly, and to obtain new information about those planets. The area pictured is one-thousandth of Kepler's full field of view, and shows hundreds of stars at the very edge of the constellation Cygnus. The image has been color-coded so that brighter stars appear white, and fainter stars, red. It is a 60-second exposure, taken on April 8, 2009, one day after the spacecraft's dust cover was jettisoned. Kepler was designed to hunt for planets like Earth. The mission will spend the next three-and-a-half years staring at the same stars, looking for periodic dips in brightness. Such dips occur when planets cross in front of their stars from our point of view in the galaxy, partially blocking the starlight. To achieve the level of precision needed to spot planets as small as Earth, Kepler's images are intentionally blurred slightly. This minimizes the number of saturated stars. Saturation, or "blooming," occurs when the brightest stars overload the individual pixels in the detectors, causing the signal to spill out into nearby pixels. http://photojournal.jpl.nasa.gov/catalog/PIA11985

  8. ECCENTRIC JUPITERS VIA DISK–PLANET INTERACTIONS

    SciTech Connect

    Duffell, Paul C.; Chiang, Eugene E-mail: echiang@astro.berkeley.edu

    2015-10-20

    Numerical hydrodynamics calculations are performed to determine the conditions under which giant planet eccentricities can be excited by parent gas disks. Unlike in other studies, Jupiter-mass planets are found to have their eccentricities amplified—provided their orbits start off as eccentric. We disentangle the web of co-rotation, co-orbital, and external resonances to show that this finite-amplitude instability is consistent with that predicted analytically. Ellipticities can grow until they reach of order of the disk's aspect ratio, beyond which the external Lindblad resonances that excite eccentricity are weakened by the planet's increasingly supersonic epicyclic motion. Forcing the planet to still larger eccentricities causes catastrophic eccentricity damping as the planet collides into gap walls. For standard parameters, the range of eccentricities for instability is modest; the threshold eccentricity for growth (∼0.04) is not much smaller than the final eccentricity to which orbits grow (∼0.07). If this threshold eccentricity can be lowered (perhaps by non-barotropic effects), and if the eccentricity driving documented here survives in 3D, it may robustly explain the low-to-moderate eccentricities ≲0.1 exhibited by many giant planets (including Jupiter and Saturn), especially those without planetary or stellar companions.

  9. Jupiter's unearthly jets: a new idealised model

    NASA Astrophysics Data System (ADS)

    Thomson, S. I.; McIntyre, M. E.

    2013-09-01

    A longstanding mystery about Jupiter has been the straightness of real Jovian jets, quite unlike terrestrial strong jets with their characteristic long-wavelength meandering. The problem is addressed in two steps. The first is to take seriously the classic Ingersoll-Cuong [4], Dowling-Ingersoll [1] and Stamp-Dowling [12] scenarios, with deep zonal jets in the convection layer underlying the weather layer, recognising moreover the relevance of Arnol'd's second shear-stability criterion ('A2 stability') and hence the possibility of stable upper jets even with reversed upper potential-vorticity (PV) gradients (e.g. [12, 2, 3]). The second step is to improve the realism of the small-scale forcing used to represent the effects of Jupiter's moist convection in physical space, albeit within an idealised, 1½-layer setting. The real moist convection is likely to generate cyclonic as well as anticyclonic PV anomalies but with unequal strengths ('PV-biased forcing'), and to occur preferentially where the interface to the deep flow is coldest (e.g. [5]). The resulting model appears to have promise as a way of explaining the jet straightness and of constraining possible values of the Rossby deformation length LD for the real planet, as well as suggesting new guidelines for general circulation model studies.

  10. Scientists Revise Thinking on Comets, Planet Jupiter

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1974

    1974-01-01

    Discusses scientific information obtained from Pioneer 10's Jupiter flyby and the comet Kohoutek's first trip around the sun, including the high hydrogen emission of Jupiter's principal moon, Io. (CC)

  11. Jupiter Great Red Spot and White Ovals

    NASA Image and Video Library

    1999-03-06

    This photo of Jupiter was taken by NASA Voyager 1 on March 1, 1979. The photo shows Jupiter Great Red Spot upper right and the turbulent region immediately to the west. http://photojournal.jpl.nasa.gov/catalog/PIA00359

  12. Scientists Revise Thinking on Comets, Planet Jupiter

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1974

    1974-01-01

    Discusses scientific information obtained from Pioneer 10's Jupiter flyby and the comet Kohoutek's first trip around the sun, including the high hydrogen emission of Jupiter's principal moon, Io. (CC)

  13. Thirteenth satellite of Jupiter. [orbit determination

    NASA Technical Reports Server (NTRS)

    Kowal, C. T.; Aksnes, K.; Marsden, B. G.; Roemer, E.

    1975-01-01

    The discovery, observations, and attempts to determine the orbit of Jupiter XIII are described. It is found that the orbit is very similar to the orbits of Jupiter VI, VII, and X. An ephemeris is provided for the 1975 opposition.

  14. Gravitational energy sources in Jupiter

    NASA Technical Reports Server (NTRS)

    Flasar, F. M.

    1973-01-01

    Gravitational sources of the intrinsic luminosity of Jupiter are examined in the context of current hydrogen-helium models. When no gravitational separation of matter occurs, the amount of heat which can be released over the remaining lifetime of the planet is necessarily limited by the size of its existing reservoir of thermal energy. This conclusion rests only on the assumption that its interior is relatively cold and degenerate. If gravitational unmixing occurs, the size of the thermal reservoir does not necessarily limit the heat output. If core formation occurs, for example, then the size of the core formed will be a limiting factor. The energy released with the formation of a helium core is computed for Jupiter. A core growth rate, averaged over several billion years, of 20 trillionths of Jupiter's mass per year is required if gravitational separation is to play a significant role in the thermal evolution.

  15. Models for Jupiter's decametric arcs

    NASA Technical Reports Server (NTRS)

    Warwick, J. W.

    1981-01-01

    Arc-shaped structures that dominate Jupiter's decametric emission are discussed in terms of a magnetic fine structure. The sequence of arcs manifest the occurence of widespread fine structures similar to the white ovals on Jupiter's visible surface. An arc concave toward increasing time occurs at the east limb passage, and an arc convex occurs at the west limb passage, which is consistent with the early source producing vertex early arcs, and the late source producing vertex late arcs. Due to the geometry of the Io plasma torus (IPT) which is arranged so that Io skims the northern surface of the IPT, for any connection between Io and Jupiter's surface that involves Alfven waves, the propagation time, the refraction and the directional defocusing of these waves must be strongly influenced by the amount of Alfven wave path length between the instantaneous position of Io and the surface of the IPT.

  16. Arsine in Saturn and Jupiter

    NASA Technical Reports Server (NTRS)

    Noll, Keith S.; Geballe, T. R.; Knacke, R. F.

    1989-01-01

    New spectra of Saturn and Jupiter are reported that show a prominent, heretofore unidentified absorption near 2126/cm. The observation is interpreted as unambiguous evidence for the presence of arsine, AsH3. The abundance of AsH3 appears to be almost a factor of two higher in Saturn than in Jupiter. The observed enrichments are consistent with the core instability model for the formation of giant planets. Models of arsenic chemistry that predict strong depletions of AsH3 at temperatures below 370 K are not consistent with the observations, suggesting that vertical convection or perhaps some other mechanism inhibits depletion. Arsenic is the first new element identified in a planetary atmosphere since germanium was found in Jupiter a decade ago.

  17. Arsine in Saturn and Jupiter

    NASA Technical Reports Server (NTRS)

    Noll, Keith S.; Geballe, T. R.; Knacke, R. F.

    1989-01-01

    New spectra of Saturn and Jupiter are reported that show a prominent, heretofore unidentified absorption near 2126/cm. The observation is interpreted as unambiguous evidence for the presence of arsine, AsH3. The abundance of AsH3 appears to be almost a factor of two higher in Saturn than in Jupiter. The observed enrichments are consistent with the core instability model for the formation of giant planets. Models of arsenic chemistry that predict strong depletions of AsH3 at temperatures below 370 K are not consistent with the observations, suggesting that vertical convection or perhaps some other mechanism inhibits depletion. Arsenic is the first new element identified in a planetary atmosphere since germanium was found in Jupiter a decade ago.

  18. Io's volcanism influences Jupiter's magnetosphere

    NASA Astrophysics Data System (ADS)

    Balcerak, Ernie

    2012-02-01

    Volcanic emissions from Jupiter's moon Io supply plasma to the planet's magnetosphere and lead to its main auroral emissions. New observations show that the main auroral oval expanded and outer emissions brightened in spring 2007. Some studies have suggested that magnetospheric changes such as these could be caused by changes in the incoming solar wind. Bonfond et al. present several lines of evidence—including images from the Hubble Space Telescope and observations of a volcanic plume on Io from the New Horizons probe along with measurements of increased emissions from Jupiter's sodium cloud—that indicate that Io's volcanism controls changes in Jupiter's magnetosphere. (Geophysical Research Letters, doi:10.1029/2011GL050253, 2012)

  19. High Resolution Globe of Jupiter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This true-color simulated view of Jupiter is composed of 4 images taken by NASA's Cassini spacecraft on December 7, 2000. To illustrate what Jupiter would have looked like if the cameras had a field-of-view large enough to capture the entire planet, the cylindrical map was projected onto a globe. The resolution is about 144 kilometers (89 miles) per pixel. Jupiter's moon Europa is casting the shadow on the planet.

    Cassini is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages Cassini for NASA's Office of Space Science, Washington, D.C.

  20. High Resolution Globe of Jupiter

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This true-color simulated view of Jupiter is composed of 4 images taken by NASA's Cassini spacecraft on December 7, 2000. To illustrate what Jupiter would have looked like if the cameras had a field-of-view large enough to capture the entire planet, the cylindrical map was projected onto a globe. The resolution is about 144 kilometers (89 miles) per pixel. Jupiter's moon Europa is casting the shadow on the planet.

    Cassini is a cooperative mission of NASA, the European Space Agency and the Italian Space Agency. JPL, a division of the California Institute of Technology in Pasadena, manages Cassini for NASA's Office of Space Science, Washington, D.C.

  1. Jupiter's Great Red Spot Revealed

    NASA Image and Video Library

    2017-07-12

    This enhanced-color image of Jupiter's Great Red Spot was created by citizen scientist Kevin Gill using data from the JunoCam imager on NASA's Juno spacecraft. The image was taken on July 10, 2017 at 07:07 p.m. PDT (10:07 p.m. EDT), as the Juno spacecraft performed its 7th close flyby of Jupiter. At the time the image was taken, the spacecraft was about 6,130 miles (9,866 kilometers) from the tops of the clouds of the planet. https://photojournal.jpl.nasa.gov/catalog/PIA21395

  2. Jupiter From Below (Enhanced Color)

    NASA Image and Video Library

    2017-02-08

    This enhanced-color image of Jupiter's south pole and its swirling atmosphere was created by citizen scientist Roman Tkachenko using data from the JunoCam imager on NASA's Juno spacecraft. Juno acquired the image, looking directly at the Jovian south pole, on February 2, 2017, at 6:06 a.m. PST (9:06 a.m. EST) from an altitude of about 63,400 miles (102,100 kilometers) above Jupiter's cloud tops. Cyclones swirl around the south pole, and white oval storms can be seen near the limb -- the apparent edge of the planet. http://photojournal.jpl.nasa.gov/catalog/PIA21381

  3. Jupiter with Satellites Io and Europa

    NASA Image and Video Library

    1996-01-29

    NASA's Voyager 1 took this photo of Jupiter and two of its satellites Io, left, and Europa on Feb. 13, 1979. Io is above Jupiter Great Red Spot; Europa is above Jupiter clouds. The poles are dark and reddish. http://photojournal.jpl.nasa.gov/catalog/PIA00144

  4. Jupiter - First stop on Voyager's grand tour

    NASA Astrophysics Data System (ADS)

    Morrison, D.

    1989-08-01

    The findings concerning Jupiter that were made by the Voyager missions are briefly reviewed. The ring and three new moons around Jupiter, the live volcanoes on Io, and atmospheric phenomena on Jupiter which were observed by Voyager 1 are described. The discoveries regarding Callisto and Europa made by Voyager 2 are briefly summarized.

  5. The Europa Jupiter system mission

    NASA Astrophysics Data System (ADS)

    Clark, K.; Stankov, A.; Pappalardo, R. T.; Greeley, R.; Blanc, M.; Lebreton, J.-P.; van Houten, T.

    2009-04-01

    Europa Jupiter System Mission (EJSM)— would be an international mission that would achieve Decadal Survey and Cosmic Vision goals. NASA and ESA have concluded a joint study of a mission to Europa, Ganymede and the Jupiter system with orbiters developed by NASA and ESA; contributions by JAXA are also possible. The baseline EJSM architecture consists of two primary elements operating in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System be-fore settling into orbit around Europa and Ganymede, respectively. JEO and JGO would carry eleven and ten complementary instruments, respectively, to monitor dynamic phenomena (such as Io's volcanoes and Jupi-ter's atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and charac-terize water oceans beneath the ice shells of Europa and Ganymede. EJSM would fully addresses high priority science objectives identified by the National Research Coun-cil's (NRC's) Decadal Survey and ESA's Cosmic Vi-sion for exploration of the outer solar system. The De-cadal Survey recommended a Europa Orbiter as the highest priority outer planet flagship mission and also identified Ganymede as a highly desirable mission tar-get. EJSM would uniquely addresse several of the cen-tral themes of ESA's Cosmic Vision Programme, through its in-depth exploration of the Jupiter system and its evolution from origin to habitability. EJSM would investigate the potential habitability of the active ocean-bearing moons Europa and Gany-mede, detailing the geophysical, compositional, geo-logical, and external processes that affect these icy worlds. EJSM would also explore Io and Callisto, Jupi-ter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant plan-ets and their satellites would be

  6. The Europa Jupiter System Mission

    NASA Astrophysics Data System (ADS)

    Hendrix, A. R.; Clark, K.; Erd, C.; Pappalardo, R.; Greeley, R. R.; Blanc, M.; Lebreton, J.; van Houten, T.

    2009-05-01

    Europa Jupiter System Mission (EJSM) will be an international mission that will achieve Decadal Survey and Cosmic Vision goals. NASA and ESA have concluded a joint study of a mission to Europa, Ganymede and the Jupiter system with orbiters developed by NASA and ESA; contributions by JAXA are also possible. The baseline EJSM architecture consists of two primary elements operating in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). The JEO mission has been selected by NASA as the next Flagship mission to the out solar system. JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. JEO and JGO would carry eleven and ten complementary instruments, respectively, to monitor dynamic phenomena (such as Io's volcanoes and Jupiter's atmosphere), map the Jovian magnetosphere and its interactions with the Galilean satellites, and characterize water oceans beneath the ice shells of Europa and Ganymede. EJSM will fully addresses high priority science objectives identified by the National Research Council's (NRC's) Decadal Survey and ESA's Cosmic Vision for exploration of the outer solar system. The Decadal Survey recommended a Europa Orbiter as the highest priority outer planet flagship mission and also identified Ganymede as a highly desirable mission target. EJSM would uniquely address several of the central themes of ESA's Cosmic Vision Programme, through its in-depth exploration of the Jupiter system and its evolution from origin to habitability. EJSM will investigate the potential habitability of the active ocean-bearing moons Europa and Ganymede, detailing the geophysical, compositional, geological and external processes that affect these icy worlds. EJSM would also explore Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the

  7. Evidence for Two Hot-Jupiter Formation Paths

    NASA Astrophysics Data System (ADS)

    Nelson, Benjamin E.; Ford, Eric B.; Rasio, Frederic A.

    2017-09-01

    Disk migration and high-eccentricity migration are two well-studied theories to explain the formation of hot Jupiters. The former predicts that these planets can migrate up until the planet-star Roche separation ({a}{Roche}) and the latter predicts they will tidally circularize at a minimum distance of 2 {a}{Roche}. Considering long-running radial velocity and transit surveys have identified a couple hundred hot Jupiters to date, we can revisit the classic question of hot-Jupiter formation in a data-driven manner. We approach this problem using data from several exoplanet surveys (radial velocity, Kepler, HAT, and WASP) allowing for either a single population or a mixture of populations associated with these formation channels, and applying a hierarchical Bayesian mixture model of truncated power laws of the form {x}γ -1 to constrain the population-level parameters of interest (e.g., location of inner edges, γ, mixture fractions). Within the limitations of our chosen models, we find that the current radial velocity and Kepler sample of hot Jupiters can be well explained with a single truncated power-law distribution with a lower cutoff near 2 {a}{Roche}, a result that still holds after a decade, and γ =-0.51{+/- }0.200.19. However, the HAT and WASP data show evidence for multiple populations (Bayes factor ≈ {10}21). We find that 15{+/- }69 % reside in a component consistent with disk migration (γ =-0.04{+/- }1.270.53) and 85{+/- }96 % in one consistent with high-eccentricity migration (γ =-1.38{+/- }0.470.32). We find no immediately strong connections with some observed host star properties and speculate on how future exoplanet surveys could improve upon hot-Jupiter population inference.

  8. Forming Different Planetary Architectures. I. The Formation Efficiency of Hot Jupiters from High-eccentricity Mechanisms

    NASA Astrophysics Data System (ADS)

    Wang, Ying; Zhou, Ji-lin; hui-gen, Liu; Meng, Zeyang

    2017-10-01

    Exoplanets discovered over the past decades have provided a new sample of giant exoplanets: hot Jupiters. For lack of enough materials in the current locations of hot Jupiters, they are perceived to form outside the snowline. Then, they migrate to the locations observed through interactions with gas disks or high-eccentricity mechanisms. We examined the efficiencies of different high-eccentricity mechanisms for forming hot Jupiters in near-coplanar multi-planet systems. These mechanisms include planet–planet scattering, the Kozai–Lidov mechanism, coplanar high-eccentricity migration, and secular chaos, as well as other two new mechanisms that we present in this work, which can produce hot Jupiters with high inclinations even in retrograde. We find that the Kozai–Lidov mechanism plays the most important role in producing hot Jupiters among these mechanisms. Secular chaos is not the usual channel for the formation of hot Jupiters due to the lack of an angular momentum deficit within {10}7{T}{in} (periods of the inner orbit). According to comparisons between the observations and simulations, we speculate that there are at least two populations of hot Jupiters. One population migrates into the boundary of tidal effects due to interactions with the gas disk, such as ups And b, WASP-47 b, and HIP 14810 b. These systems usually have at least two planets with lower eccentricities, and remain dynamically stable in compact orbital configurations. Another population forms through high-eccentricity mechanisms after the excitation of eccentricity due to dynamical instability. These kinds of hot Jupiters usually have Jupiter-like companions in distant orbits with moderate or high eccentricities.

  9. Energetic electrons in Jupiter's dawn magnetodisc

    NASA Technical Reports Server (NTRS)

    Van Allen, J. A.

    1979-01-01

    The paper presents and analyzes absolute energy density data on electrons from the University of Iowa instrument on Pioneer 10 for one example of a plasma sheet traversal in Jupiter's dawn magnetodisk on 6-7 December 1973. The absolute integral omnidirectional intensity spectrum of electrons is based on a full and accurate reduction of the counting rate data. The main finding is that electrons of energy greater than 0.060 MeV provide only about 3% of the charged particle pressure required to explain the observed depression in the magnetic field at the center of the plasma sheet, in spite of the fact that the intensity of such electrons is well correlated with the depression of the magnetic pressure throughout the sheet.

  10. Jupiter's decametric radio emission - A nice problem of optics

    NASA Astrophysics Data System (ADS)

    Lecacheux, A.; Meyer-Vernet, N.; Daigne, G.

    1981-02-01

    We show that the spectral and temporal 'nested arcs' pattern of the Jovian decametric radio-dynamic spectrum can be interpreted as due solely to the diffraction of a radio-source by a phase changing plasma structure, located permanently in Jupiter's magnetosphere and rotating with the planet. This entirely new approach of the phenomenon explains in a simple way many observational features not understood so far. It allows to reinterpret the observations, thus yielding new constraints on the physics of the emission.

  11. The Voyager Spacecraft. [Jupiter-Saturn mission investigations

    NASA Technical Reports Server (NTRS)

    1979-01-01

    The configuration of the Voyager spacecraft is described as well as the subsystems for power, temperature control, attitude control, and propulsion. Major features of Jupiter and Saturn including their atmospheres, surfaces, and natural satellites are discussed. The 13 onboard experiments and their scientific objectives are explained. Other aspects covered include tracking, data acquisition, and the mission control and computing center. Members of the Voyager team and subcontractors are listed.

  12. HUBBLE VIEWS ANCIENT STORM IN THE ATMOSPHERE OF JUPITER

    NASA Technical Reports Server (NTRS)

    2002-01-01

    When 17th-century astronomers first turned their telescopes to Jupiter, they noted a conspicuous reddish spot on the giant planet. This Great Red Spot is still present in Jupiter's atmosphere, more than 300 years later. It is now known that it is a vast storm, spinning like a cyclone. Unlike a low-pressure hurricane in the Caribbean Sea, however, the Red Spot rotates in a counterclockwise direction in the southern hemisphere, showing that it is a high-pressure system. Winds inside this Jovian storm reach speeds of about 270 mph. The Red Spot is the largest known storm in the Solar System. With a diameter of 15,400 miles, it is almost twice the size of the entire Earth and one-sixth the diameter of Jupiter itself. The long lifetime of the Red Spot may be due to the fact that Jupiter is mainly a gaseous planet. It possibly has liquid layers, but lacks a solid surface, which would dissipate the storm's energy, much as happens when a hurricane makes landfall on the Earth. However, the Red Spot does change its shape, size, and color, sometimes dramatically. Such changes are demonstrated in high-resolution Wide Field and Planetary Cameras 1 and 2 images of Jupiter obtained by NASA's Hubble Space Telescope, and presented here by the Hubble Heritage Project team. The mosaic presents a series of pictures of the Red Spot obtained by Hubble between 1992 and 1999. Astronomers study weather phenomena on other planets in order to gain a greater understanding of our own Earth's climate. Lacking a solid surface, Jupiter provides us with a laboratory experiment for observing weather phenomena under very different conditions than those prevailing on Earth. This knowledge can also be applied to places in the Earth's atmosphere that are over deep oceans, making them more similar to Jupiter's deep atmosphere. The Hubble images were originally collected by Amy Simon (Cornell U.), Reta Beebe (NMSU), Heidi Hammel (Space Science Institute, MIT), and their collaborators, and have been

  13. HUBBLE VIEWS ANCIENT STORM IN THE ATMOSPHERE OF JUPITER

    NASA Technical Reports Server (NTRS)

    2002-01-01

    When 17th-century astronomers first turned their telescopes to Jupiter, they noted a conspicuous reddish spot on the giant planet. This Great Red Spot is still present in Jupiter's atmosphere, more than 300 years later. It is now known that it is a vast storm, spinning like a cyclone. Unlike a low-pressure hurricane in the Caribbean Sea, however, the Red Spot rotates in a counterclockwise direction in the southern hemisphere, showing that it is a high-pressure system. Winds inside this Jovian storm reach speeds of about 270 mph. The Red Spot is the largest known storm in the Solar System. With a diameter of 15,400 miles, it is almost twice the size of the entire Earth and one-sixth the diameter of Jupiter itself. The long lifetime of the Red Spot may be due to the fact that Jupiter is mainly a gaseous planet. It possibly has liquid layers, but lacks a solid surface, which would dissipate the storm's energy, much as happens when a hurricane makes landfall on the Earth. However, the Red Spot does change its shape, size, and color, sometimes dramatically. Such changes are demonstrated in high-resolution Wide Field and Planetary Cameras 1 and 2 images of Jupiter obtained by NASA's Hubble Space Telescope, and presented here by the Hubble Heritage Project team. The mosaic presents a series of pictures of the Red Spot obtained by Hubble between 1992 and 1999. Astronomers study weather phenomena on other planets in order to gain a greater understanding of our own Earth's climate. Lacking a solid surface, Jupiter provides us with a laboratory experiment for observing weather phenomena under very different conditions than those prevailing on Earth. This knowledge can also be applied to places in the Earth's atmosphere that are over deep oceans, making them more similar to Jupiter's deep atmosphere. The Hubble images were originally collected by Amy Simon (Cornell U.), Reta Beebe (NMSU), Heidi Hammel (Space Science Institute, MIT), and their collaborators, and have been

  14. Heavy ions in Jupiter's environment

    NASA Technical Reports Server (NTRS)

    Brown, R. A.

    1980-01-01

    The extended atmosphere of the Jupiter system consists of atoms and ions of heavy elements. This material originates on the satellite Io. Energy is lost from the thermal plasma in collisionally excited optical and ultraviolet emission. The juxtaposition of Earth and spacecraft measurements provide insight concerning the underlying processes of particle transport and energy supply.

  15. Origins of Hot Jupiters, Revisited

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin; Bodenheimer, Peter; Laughlin, Greg

    2015-12-01

    Hot Jupiters, giant extrasolar planets with orbital periods less than ~10 days, have long been thought to form at large radial distances (a > 2AU) in protostellar disks, only to subsequently experience large-scale inward migration to the small orbital radii at which they are observed. Here, we propose that a substantial fraction of the hot Jupiter population forms in situ, with the Galactically prevalent short-period super-Earths acting as the source population. Our calculations suggest that under conditions appropriate to the inner regions of protostellar disks, rapid gas accretion can be initiated for solid cores of 10-20 Earth masses, in line with the conventional picture of core-nucleated accretion. This formation scenario leads to testable consequences, including the expectation that hot Jupiters should frequently be accompanied by additional planets, reminiscent of those observed in large numbers by NASA’s Kepler Mission and Doppler velocity surveys. However, dynamical interactions during the early stages of planetary systems' evolutionary lifetimes tend to increase the mutual inclinations of exterior, low-mass companions to hot Jupiters, making transits rare. High-precision radial velocity monitoring provides the best prospect for their detection.

  16. Origins of Hot Jupiters, Revisited

    NASA Astrophysics Data System (ADS)

    Batygin, Konstantin; Bodenheimer, Peter; Laughlin, Greg

    2016-05-01

    Hot Jupiters, giant extrasolar planets with orbital periods less than ~10 days, have long been thought to form at large radial distances (a > 2AU) in protoplanetary disks, only to subsequently experience large-scale inward migration to the small orbital radii at which they are observed. Here, we propose that a substantial fraction of the hot Jupiter population forms in situ, with the Galactically prevalent short-period super-Earths acting as the source population. Our calculations suggest that under conditions appropriate to the inner regions of protoplanetary disks, rapid gas accretion can be initiated for solid cores of 10-20 Earth masses, in line with the conventional picture of core-nucleated accretion. The planetary conglomeration process, coupled with subsequent gravitational contraction and spin down of the host star, drives sweeping secular resonances through the system, increasing the mutual inclinations of exterior, low-mass companions to hot Jupiters. Accordingly, this formation scenario leads to testable consequences, including the expectation that hot Jupiters should frequently be accompanied by additional non-transiting planets, reminiscent of those observed in large numbers by NASA’s Kepler Mission and Doppler velocity surveys. High-precision radial velocity monitoring provides the best prospect for their detection.

  17. Jupiter Great Red Spot Region

    NASA Image and Video Library

    1996-09-26

    This mosaic of Jupiter Great Red Spot taken by NASA Voyager 1, shows the area around the northern boundary where a white cloud is seen which extends to east of the region. http://photojournal.jpl.nasa.gov/catalog/PIA00065

  18. Massive Gas Cloud Around Jupiter

    NASA Technical Reports Server (NTRS)

    2003-01-01

    An innovative instrument on NASA's Cassini spacecraft makes the space environment around Jupiter visible, revealing a donut-shaped gas cloud encircling the planet.

    The image was taken with the energetic neutral atom imaging technique by the Magnetospheric Imaging Instrument on Cassini as the spacecraft flew past Jupiter in early 2001 at a distance of about 10 million kilometers (6 million miles). This technique provides information about a source by detecting neutral atoms emitted by the source, comparable to how a camera reveals information about an object by detecting photons coming from the object.

    The central object in this image represents energetic neutral atom emissions from Jupiter itself. The outer two objects represent emissions from a donut-shaped cloud, or torus, that shares an orbit with Jupiter's moon Europa. The cloud's emissions appear dot-like because of the viewing angle. The torus is viewed edge-on, and the image is brightest at the line-of-sight angles that pass through the greatest volume of it.

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages Cassini for NASA's Office of Space Science, Washington, D.C.

  19. Peering Deep into Jupiter Atmosphere

    NASA Image and Video Library

    2013-03-14

    The dark hot spot in this false-color image from NASA Cassini spacecraft is a window deep into Jupiter atmosphere. All around it are layers of higher clouds, with colors indicating which layer of the atmosphere the clouds are in.

  20. Mesoscale Waves in Jupiter Atmosphere

    NASA Image and Video Library

    1997-09-07

    These two images of Jupiter atmosphere were taken with the violet filter of the Solid State Imaging CCD system aboard NASA Galileo spacecraft. Mesoscale waves can be seen in the center of the upper image. The images were obtained on June 26, 1996.

  1. Voyager to Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    1977-01-01

    The NASA Voyager mission to explore planets of the outer solar system is summarized. The mission schedule and profiles for encounters with Jupiter and Saturn, and possibly with Uranus and Pluto are included along with a description of the spacecraft and its trajectories. Scientific investigations to be made and the instruments carried are also discussed.

  2. Heat Map of Jupiter Impact

    NASA Image and Video Library

    2011-01-26

    This infrared image, showing thermal radiation at a wavelength of 9.7 microns, was obtained by the Gemini North Telescope in Hawaii. The bright white and yellow features at bottom are the aftermath of an impactor hitting Jupiter on July 19, 2009.

  3. Galileo: Challenges enroute to Jupiter

    NASA Astrophysics Data System (ADS)

    O'Neil, William J.

    The Galileo spacecraft is now on its three-year direct Earth-to-Jupiter transfer trajectory. Jupiter arrived (Probe entry) is scheduled for 2:05 pm PST, December 7, 1995. The Galileo Probe will be the first human-made object to enter the atmosphere of an outer planet, while the Orbiter will be the first artificial satellite of an outer planet. A two-year Jupiter orbital mission is planned. Following launch on October 18, 1989, Galileo spent just over three years executing its Venus-Earth-Earth Gravity Assist (VEEGA) mission phase to achieve the heliocentric energy necessary to reach Jupiter. Midway through its Earth-to-Earth leg, on October 29, 1991, Galileo became the first spacecraft to encounter an asteroid. Six months earlier in April 1991, the spacecraft's high-gain antenna (HGA) failed to deploy properly. The special guidance, navigation, and control (GN&C) problems associated with a 20-month campaign of maneuvers to free the stuck antenna and successfully perform the asteroid encounter without it are described. The overall mission and spacecraft status are also reported.

  4. Water vapor in Jupiter's atmosphere

    NASA Technical Reports Server (NTRS)

    Bjoraker, G. L.; Larson, H. P.; Kunde, V. G.

    1986-01-01

    High spectral resolution observations of Jupiter at 2.7 and 5 microns acquired from the Kuiper Airborne Observatory were used to infer the vertical distribution of H2O between 0.7 and 6 bars. The H2O mole fraction, qH2O, is saturated for P<2 bars, qH2O = 4x.000001 in the 2 to 4 bar range and it increases to 3x.00001 at 6 bars where T = 288 K. The base of the 5 micron line formation region is determined by pressure-induced H2 opacity. At this deepest accessible level, the O/H ratio in Jupiter is depleted by a factor of 50 with respect to the solar atmosphere. High spatial resolution Voyager IRIS spectra of Jupiter's North Tropical Zone, Equatorial Zone, and Hot Spots in the North and South Equatorial Belt were analyzed to determine the spatial variation of H2O across the planet. The column abundance of H2O above the 4 bar level is the same in the zones as in the SEB Hot Spots, about 20 cm-amgt. A cloud model for Jupiter's belts and zones was developed in order to fit the IRIS 5 micron spectra. An absorbing cloud located at 2 bars whose 5 micron optical thickness varies between 1 in the Hot Spots and 4 in the coldest zones satisfactorily matches the IRIS data.

  5. Alice Views Jupiter and Io

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This graphic illustrates the pointing and shows the data from one of many observations made by the New Horizons Alice ultraviolet spectrometer (UVS) instrument during the Pluto-bound spacecraft's recent encounter with Jupiter. The red lines in the graphic show the scale, orientation, and position of the combined 'box and slot' field of view of the Alice UVS during this observation.

    The positions of Jupiter's volcanic moon, Io, the torus of ionized gas from Io, and Jupiter are shown relative to the Alice field of view. Like a prism, the spectrometer separates light from these targets into its constituent wavelengths.

    Io's volcanoes produce an extremely tenuous atmosphere made up primarily of sulfur dioxide gas, which, in the harsh plasma environment at Io, breaks down into its component sulfur and oxygen atoms. Alice observed the auroral glow from these atoms in Io's atmosphere and their ionized counterparts in the Io torus.

    Io's dayside is deliberately overexposed to bring out faint details in the plumes and on the moon's night side. The continuing eruption of the volcano Tvashtar, at the 1 o'clock position, produces an enormous plume roughly 330 kilometers (200 miles) high, which is illuminated both by sunlight and 'Jupiter light.'

  6. Jupiter. [internal structure and atmosphere

    NASA Technical Reports Server (NTRS)

    Wolfe, J. H.

    1975-01-01

    The physical structure of Jupiter is discussed on the basis of data obtained by Pioneers 10 and 11. It is argued that the elemental composition of Jupiter is similar to that of the sun, and it is shown that this argument is supported by measurements of the planet's density and H/He ratio. Jupiter's shape and gravitational field are described, and a model of the planet is proposed in which there are a small iron-silicate core at the center, a very thick liquid-hydrogen stratum divided into metallic (inner) and molecular (outer) layers, and a gaseous atmosphere. According to this model, the excess heat radiated by Jupiter is simply a remnant of the heat generated when the planet coalesced from the solar nebula. The appearance of the planetary disk is described together with the Jovian magnetic field, and the Great Red Spot is shown to be a cyclonic disturbance similar to a hurricane. Effects of the Galilean satellites on the magnetic field are considered.

  7. Massive Gas Cloud Around Jupiter

    NASA Technical Reports Server (NTRS)

    2003-01-01

    An innovative instrument on NASA's Cassini spacecraft makes the space environment around Jupiter visible, revealing a donut-shaped gas cloud encircling the planet.

    The image was taken with the energetic neutral atom imaging technique by the Magnetospheric Imaging Instrument on Cassini as the spacecraft flew past Jupiter in early 2001 at a distance of about 10 million kilometers (6 million miles). This technique provides information about a source by detecting neutral atoms emitted by the source, comparable to how a camera reveals information about an object by detecting photons coming from the object.

    The central object in this image represents energetic neutral atom emissions from Jupiter itself. The outer two objects represent emissions from a donut-shaped cloud, or torus, that shares an orbit with Jupiter's moon Europa. The cloud's emissions appear dot-like because of the viewing angle. The torus is viewed edge-on, and the image is brightest at the line-of-sight angles that pass through the greatest volume of it.

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages Cassini for NASA's Office of Space Science, Washington, D.C.

  8. SUPER-ECCENTRIC MIGRATING JUPITERS

    SciTech Connect

    Socrates, Aristotle; Katz, Boaz; Dong Subo; Tremaine, Scott

    2012-05-10

    An important class of formation theories for hot Jupiters involves the excitation of extreme orbital eccentricity (e = 0.99 or even larger) followed by tidal dissipation at periastron passage that eventually circularizes the planetary orbit at a period less than 10 days. In a steady state, this mechanism requires the existence of a significant population of super-eccentric (e > 0.9) migrating Jupiters with long orbital periods and periastron distances of only a few stellar radii. For these super-eccentric planets, the periastron is fixed due to conservation of orbital angular momentum and the energy dissipated per orbit is constant, implying that the rate of change in semi-major axis a is a-dot {proportional_to}a{sup 1/2} and consequently the number distribution satisfies dN/d log a{proportional_to}a{sup 1/2}. If this formation process produces most hot Jupiters, Kepler should detect several super-eccentric migrating progenitors of hot Jupiters, allowing for a test of high-eccentricity migration scenarios.

  9. Hot Jupiters Aren't As Lonely As We Thought

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2016-01-01

    The Friends of Hot Jupiters (FOHJ) project is a systematic search for planetary- and stellar-mass companions in systems that have known hot Jupiters short-period, gas-giant planets. This survey has discovered that many more hot Jupiters may have companions than originally believed.Missing FriendsFOHJ was begun with the goal of better understanding the systems that host hot Jupiters, in order to settle several longstanding issues.The first problem was one of observational statistics. We know that roughly half of the Sun-like stars nearby are in binary systems, yet weve only discovered a handful of hot Jupiters around binaries. Are binary systems less likely to host hot Jupiters? Or have we just missed the binary companions in the hot-Jupiter-hosting systems weve seen so far?An additional issue relates to formation mechanisms. Hot Jupiters probably migrated inward from where they formed out beyond the ice lines in protoplanetary disks but how?This median-stacked image, obtained with adaptive optics, shows one of the newly-discovered stellar companions to a star hosting a hot Jupiter. The projected separation is ~180 AU. [Ngo et al. 2015]Observations reveal two populations of hot Jupiters: those with circular orbits aligned with their hosts spins, and those with eccentric, misaligned orbits. The former population support a migration model dominated by local planet-disk interactions, whereas the latter population suggest the hot Jupiters migrated through dynamical interactions with distant companions. A careful determination of the companion rate in hot-Jupiter-hosting systems could help establish the ability of these two models to explain the observed populations.Search for CompanionsThe FOHJ project began in 2012 and studied 51 systems hosting known, transiting hot Jupiters with roughly half on circular, aligned orbits and half on eccentric, misaligned orbits. The survey consisted of three different, complementary components:Study 1Lead author: Heather Knutson

  10. Improved mapping of Jupiter's auroral features to magnetospheric sources

    NASA Astrophysics Data System (ADS)

    Vogt, Marissa F.; Kivelson, Margaret G.; Khurana, Krishan K.; Walker, Raymond J.; Bonfond, Bertrand; Grodent, Denis; Radioti, Aikaterini

    2011-03-01

    The magnetospheric mapping of Jupiter's polar auroral emissions is highly uncertain because global Jovian field models are known to be inaccurate beyond ˜30 RJ. Furthermore, the boundary between open and closed flux in the ionosphere is not well defined because, unlike the Earth, the main auroral oval emissions at Jupiter are likely associated with the breakdown of plasma corotation and not the open/closed flux boundary in the polar cap. We have mapped contours of constant radial distance from the magnetic equator to the ionosphere in order to understand how auroral features relate to magnetospheric sources. Instead of following model field lines, we map equatorial regions to the ionosphere by requiring that the magnetic flux in some specified region at the equator equals the magnetic flux in the area to which it maps in the ionosphere. Equating the fluxes in this way allows us to link a given position in the magnetosphere to a position in the ionosphere. We find that the polar auroral active region maps to field lines beyond the dayside magnetopause that can be interpreted as Jupiter's polar cusp; the swirl region maps to lobe field lines on the night side and can be interpreted as Jupiter's polar cap; the dark region spans both open and closed field lines and must be explained by multiple processes. Additionally, we conclude that the flux through most of the area inside the main oval matches the magnetic flux contained in the magnetotail lobes and is probably open to the solar wind.

  11. Ultra-relativistic electrons in Jupiter's radiation belts.

    PubMed

    Bolton, S J; Janssen, M; Thorne, R; Levin, S; Klein, M; Gulkis, S; Bastian, T; Sault, R; Elachi, C; Hofstadter, M; Bunker, A; Dulk, G; Gudim, E; Hamilton, G; Johnson, W T K; Leblanc, Y; Liepack, O; McLeod, R; Roller, J; Roth, L; West, R

    2002-02-28

    Ground-based observations have shown that Jupiter is a two-component source of microwave radio emission: thermal atmospheric emission and synchrotron emission from energetic electrons spiralling in Jupiter's magnetic field. Later in situ measurements confirmed the existence of Jupiter's high-energy electron-radiation belts, with evidence for electrons at energies up to 20[?]MeV. Although most radiation belt models predict electrons at higher energies, adiabatic diffusion theory can account only for energies up to around 20[?]MeV. Unambiguous evidence for more energetic electrons is lacking. Here we report observations of 13.8[?]GHz synchrotron emission that confirm the presence of electrons with energies up to 50[?]MeV; the data were collected during the Cassini fly-by of Jupiter. These energetic electrons may be repeatedly accelerated through an interaction with plasma waves, which can transfer energy into the electrons. Preliminary comparison of our data with model results suggests that electrons with energies of less than 20[?]MeV are more numerous than previously believed.

  12. Jupiter's High-Altitude Clouds

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons Multispectral Visible Imaging Camera (MVIC) snapped this incredibly detailed picture of Jupiter's high-altitude clouds starting at 06:00 Universal Time on February 28, 2007, when the spacecraft was only 2.3 million kilometers (1.4 million miles) from the solar system's largest planet. Features as small as 50 kilometers (30 miles) are visible. The image was taken through a narrow filter centered on a methane absorption band near 890 nanometers, a considerably redder wavelength than what the eye can see. Images taken through this filter preferentially pick out clouds that are relatively high in the sky of this gas giant planet because sunlight at the wavelengths transmitted by the filter is completely absorbed by the methane gas that permeates Jupiter's atmosphere before it can reach the lower clouds.

    The image reveals a range of diverse features. The south pole is capped with a haze of small particles probably created by the precipitation of charged particles into the polar regions during auroral activity. Just north of the cap is a well-formed anticyclonic vortex with rising white thunderheads at its core. Slightly north of the vortex are the tendrils of some rather disorganized storms and more pinpoint-like thunderheads. The dark 'measles' that appear a bit farther north are actually cloud-free regions where light is completely absorbed by the methane gas and essentially disappears from view. The wind action considerably picks up in the equatorial regions where giant plumes are stretched into a long wave pattern. Proceeding north of the equator, cirrus-like clouds are shredded by winds reaching speeds of up to 400 miles per hour, and more pinpoint-like thunderheads are visible. Although some of the famous belt and zone structure of Jupiter's atmosphere is washed out when viewed at this wavelength, the relatively thin North Temperate Belt shows up quite nicely, as does a series of waves just north of the belt. The north polar region of

  13. Jupiter: Cosmic Jekyll and Hyde.

    PubMed

    Grazier, Kevin R

    2016-01-01

    It has been widely reported that Jupiter has a profound role in shielding the terrestrial planets from comet impacts in the Solar System, and that a jovian planet is a requirement for the evolution of life on Earth. To evaluate whether jovians, in fact, shield habitable planets from impacts (a phenomenon often referred to as the "Jupiter as shield" concept), this study simulated the evolution of 10,000 particles in each of the jovian inter-planet gaps for the cases of full-mass and embryo planets for up to 100 My. The results of these simulations predict a number of phenomena that not only discount the "Jupiter as shield" concept, they also predict that in a Solar System like ours, large gas giants like Saturn and Jupiter had a different, and potentially even more important, role in the evolution of life on our planet by delivering the volatile-laden material required for the formation of life. The simulations illustrate that, although all particles occupied "non-life threatening" orbits at their onset of the simulations, a significant fraction of the 30,000 particles evolved into Earth-crossing orbits. A comparison of multiple runs with different planetary configurations revealed that Jupiter was responsible for the vast majority of the encounters that "kicked" outer planet material into the terrestrial planet region, and that Saturn assisted in the process far more than has previously been acknowledged. Jupiter also tends to "fix" the aphelion of planetesimals at its orbit irrespective of their initial starting zones, which has the effect of slowing their passages through the inner Solar System, and thus potentially improving the odds of accretion of cometary material by terrestrial planets. As expected, the simulations indicate that the full-mass planets perturb many objects into the deep outer Solar System, or eject them entirely; however, planetary embryos also did this with surprising efficiency. Finally, the simulations predict that Jupiter's capacity to

  14. Jupiter's High-Altitude Clouds

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The New Horizons Multispectral Visible Imaging Camera (MVIC) snapped this incredibly detailed picture of Jupiter's high-altitude clouds starting at 06:00 Universal Time on February 28, 2007, when the spacecraft was only 2.3 million kilometers (1.4 million miles) from the solar system's largest planet. Features as small as 50 kilometers (30 miles) are visible. The image was taken through a narrow filter centered on a methane absorption band near 890 nanometers, a considerably redder wavelength than what the eye can see. Images taken through this filter preferentially pick out clouds that are relatively high in the sky of this gas giant planet because sunlight at the wavelengths transmitted by the filter is completely absorbed by the methane gas that permeates Jupiter's atmosphere before it can reach the lower clouds.

    The image reveals a range of diverse features. The south pole is capped with a haze of small particles probably created by the precipitation of charged particles into the polar regions during auroral activity. Just north of the cap is a well-formed anticyclonic vortex with rising white thunderheads at its core. Slightly north of the vortex are the tendrils of some rather disorganized storms and more pinpoint-like thunderheads. The dark 'measles' that appear a bit farther north are actually cloud-free regions where light is completely absorbed by the methane gas and essentially disappears from view. The wind action considerably picks up in the equatorial regions where giant plumes are stretched into a long wave pattern. Proceeding north of the equator, cirrus-like clouds are shredded by winds reaching speeds of up to 400 miles per hour, and more pinpoint-like thunderheads are visible. Although some of the famous belt and zone structure of Jupiter's atmosphere is washed out when viewed at this wavelength, the relatively thin North Temperate Belt shows up quite nicely, as does a series of waves just north of the belt. The north polar region of

  15. Io in Front of Jupiter

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Jupiter's four largest satellites, including Io, the golden ornament in front of Jupiter in this image from NASA's Cassini spacecraft, have fascinated Earthlings ever since Galileo Galilei discovered them in 1610 in one of his first astronomical uses of the telescope.

    Images from Cassini that will be released over the next several days capture each of the four Galilean satellites in their orbits around the giant planet.

    This true-color composite frame, made from narrow angle images taken on Dec. 12, 2000, captures Io and its shadow in transit against the disk of Jupiter. The distance of the spacecraft from Jupiter was 19.5 million kilometers (12.1 million miles). The image scale is 117 kilometers (73 miles) per pixel.

    The entire body of Io, about the size of Earth's Moon, is periodically flexed as it speeds around Jupiter and feels, as a result of its non-circular orbit, the periodically changing gravitational pull of the planet. The heat arising in Io's interior from this continual flexure makes it the most volcanically active body in the solar system, with more than 100 active volcanoes. The white and reddish colors on its surface are due to the presence of different sulfurous materials. The black areas are silicate rocks.

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of Space Science, Washington, D.C.

  16. Nine Frames as Jupiter Turns

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This sequence of nine true-color, narrow-angle images shows the varying appearance of Jupiter as it rotated through more than a complete 360-degree turn. The smallest features seen in this sequence are no bigger than about 380 kilometers (about 236 miles). Rotating more than twice as fast as Earth, Jupiter completes one rotation in about 10 hours. These images were taken on Oct. 22 and 23, 2000. From image to image (proceeding left to right across each row and then down to the next row), cloud features on Jupiter move from left to right before disappearing over the edge onto the nightside of the planet. The most obvious Jovian feature is the Great Red Spot, which can be seen moving onto the dayside in the third frame (below and to the left of the center of the planet). In the fourth frame, taken about 1 hour and 40 minutes later, the Great Red Spot has been carried by the planet's rotation to the east and does not appear again until the final frame, which was taken one complete rotation after the third frame.

    Unlike weather systems on Earth, which change markedly from day to day, large cloud systems in Jupiter's colder, thicker atmosphere are long-lived, so the two frames taken one rotation apart have a very similar appearance. However, when this sequence of images is eventually animated, strong winds blowing eastward at some latitudes and westward at other latitudes will be readily apparent. The results of such differential motions can be seen even in the still frames shown here. For example, the clouds of the Great Red Spot rotate counterclockwise. The strong westward winds northeast of the Great Red Spot are deflected around the spot and form a wake of turbulent clouds downstream (visible in the fourth image), just as a rock in a rapidly flowing river deflects the fluid around it.

    The equatorial zone on Jupiter is currently bright white, indicating the presence of clouds much like cirrus clouds on Earth, but made of ammonia instead of water ice. This

  17. Nine Frames as Jupiter Turns

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This sequence of nine true-color, narrow-angle images shows the varying appearance of Jupiter as it rotated through more than a complete 360-degree turn. The smallest features seen in this sequence are no bigger than about 380 kilometers (about 236 miles). Rotating more than twice as fast as Earth, Jupiter completes one rotation in about 10 hours. These images were taken on Oct. 22 and 23, 2000. From image to image (proceeding left to right across each row and then down to the next row), cloud features on Jupiter move from left to right before disappearing over the edge onto the nightside of the planet. The most obvious Jovian feature is the Great Red Spot, which can be seen moving onto the dayside in the third frame (below and to the left of the center of the planet). In the fourth frame, taken about 1 hour and 40 minutes later, the Great Red Spot has been carried by the planet's rotation to the east and does not appear again until the final frame, which was taken one complete rotation after the third frame.

    Unlike weather systems on Earth, which change markedly from day to day, large cloud systems in Jupiter's colder, thicker atmosphere are long-lived, so the two frames taken one rotation apart have a very similar appearance. However, when this sequence of images is eventually animated, strong winds blowing eastward at some latitudes and westward at other latitudes will be readily apparent. The results of such differential motions can be seen even in the still frames shown here. For example, the clouds of the Great Red Spot rotate counterclockwise. The strong westward winds northeast of the Great Red Spot are deflected around the spot and form a wake of turbulent clouds downstream (visible in the fourth image), just as a rock in a rapidly flowing river deflects the fluid around it.

    The equatorial zone on Jupiter is currently bright white, indicating the presence of clouds much like cirrus clouds on Earth, but made of ammonia instead of water ice. This

  18. Jupiter Polar Winds Movie Blowup

    NASA Technical Reports Server (NTRS)

    2001-01-01

    Persistent polar storms and zonal winds on Jupiter can be seen in this magnified quadrant from a movie projecting images from NASA's Cassini spacecraft as if the viewer were looking down at Jupiter's north pole and the planet were flattened.

    The sequence covers 70 days, from October 1 to December 9, 2000. Cassini's narrow-angle camera captured the images of Jupiter's atmosphere in the near-infrared region of the spectrum.

    Like the accompanying full-circle movie of polar winds, this zoomed-inversion shows that the polar region has coherent flows, despite its chaotic, mottled appearance. There are thousands of spots, each an active storm similar in size to the largest storms on Earth. The spots occasionally change latitude or merge with each other, but usually they last for the entire 70 days. Until now, the lifetime of those storms was unknown.

    The mystery of Jupiter's weather is why the storms last so long. Storms on Earth last for a week before they break up and are replaced by other storms. This movie heightens the mystery because it shows long-lived storms at the highest latitudes, where the weather patterns are more disorganized than at low latitudes.

    Cassini collected images of Jupiter for months before and after it passed the planet on December 30, 2000. Six images or more of the planet in each of several spectral filters were taken at evenly spaced intervals over the course of Jupiter's 10-hour rotation period. The entire sequence was repeated generally every other Jupiter rotation, yielding views of every sector of the planet at least once every 20 hours.

    The images used for the movie shown here were taken every 20 hours through a filter centered at a wavelength of 756 nanometers, where there are almost no absorptions in the planet's atmosphere. Images from each rotation were assembled first into a cylindrical map. The 84 resulting cylindrical maps, spanning 70 Earth days or 168 Jupiter rotations, were transformed to polar stereographic

  19. Structure and Evolution of Internally Heated Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Youdin, Andrew N.

    2017-08-01

    Hot Jupiters receive strong stellar irradiation, producing equilibrium temperatures of 1000{--}2500 {{K}}. Incoming irradiation directly heats just their thin outer layer, down to pressures of ∼0.1 bars. In standard irradiated evolution models of hot Jupiters, predicted transit radii are too small. Previous studies have shown that deeper heating—at a small fraction of the heating rate from irradiation—can explain observed radii. Here we present a suite of evolution models for HD 209458b, where we systematically vary both the depth and intensity of internal heating, without specifying the uncertain heating mechanism(s). Our models start with a hot, high-entropy planet whose radius decreases as the convective interior cools. The applied heating suppresses this cooling. We find that very shallow heating—at pressures of 1{--}10 {bars}—does not significantly suppress cooling, unless the total heating rate is ≳ 10 % of the incident stellar power. Deeper heating, at 100 bars, requires heating at only 1% of the stellar irradiation to explain the observed transit radius of 1.4{R}{Jup} after 5 Gyr of cooling. In general, more intense and deeper heating results in larger hot-Jupiter radii. Surprisingly, we find that heat deposited at {10}4 {bars}—which is exterior to ≈ 99 % of the planet’s mass—suppresses planetary cooling as effectively as heating at the center. In summary, we find that relatively shallow heating is required to explain the radii of most hot Jupiters, provided that this heat is applied early and persists throughout their evolution.

  20. What do the compositions of the regular satellites of Jupiter and Saturn tell us?

    NASA Astrophysics Data System (ADS)

    Mosqueira, I.; Podolak, M.

    2012-12-01

    Models for the formation of the regular satellites of Jupiter and Saturn are hampered by our lack of understanding of the turbulent state of the subnebula and the gas-inflow rate [1]. Fortunately, it is possible to construct regular satellite formation models that are not dependent on specific choices for these parameters [2,3]. These two approaches treat planetesimal dynamics explicitly (which is a model requirement [1]), and also account for the angular momentum budget of the regular satellites. The inner satellites of Jupiter, Io and Europa, are depleted of volatiles either due to the temperature gradient in the subnebula [4,5], collisional processes involving differentiated objects [6], and/or the Laplace resonance. The observed densities of the Saturnian regular satellites are not compatible with solar compositions [7]. The inner satellites of Saturn (inside of Titan) include a stochastic compositional component (e.g., Tethys vs. Enceladus) due to collisional processes deep in the kronian gravitational-potential well; however, such an argument can not be applied to faraway and isolated Iapetus. ([8] consider a collisional scattering origin for Iapetus, but we favor the model we present here.) The bulk compositional and size similarities between Ganymede, Callisto and Titan argue strongly in favor of non-stochastic processes for these satellites. Therefore, the non-stochastic masses and densities of the large, outer regular satellites of Jupiter and Saturn (Ganymede, Callisto, Titan and Iapetus) provide the most directly useful constraints for satellite formation models. Observations indicate that Kuiper Belt Objects (KBOs) are of different composition than the regular satellites of Jupiter and Saturn. The simplest explanation of the observations is that the subnebulae of these giant planets are enriched in water-ice compared to the outer solar nebula [7]. The contrast between icy Iapetus and rocky Phoebe reinforces the interpretation of Phoebe as a moon

  1. 70 Days of Jupiter Winds

    NASA Technical Reports Server (NTRS)

    2001-01-01

    This global movie of 70 days of Jupiter's cloud movements photographed by NASA's Cassini spacecraft shows that zones of eastward and westward winds cover the planet virtually from pole to pole.

    Cassini's narrow-angle camera captured the images of Jupiter's atmosphere from October 1 to December 9, 2000, in the near-infrared region of the spectrum. The view here is a cylindrical projection centered in the planet's equator.

    The movie allows tracking of individual storms' movements in the familiar zonal bands of the lower latitudes, in the swirling turbulence around the Great Red Spot and in the high latitudes where still images show chaotic mottling instead of stripes.

    Cassini collected images of Jupiter for months before and after it passed the planet on December 30, 2000. Six or more images of the planet in each of several spectral filters were taken at evenly spaced intervals over the course of Jupiter's 10-hour rotation period. The entire sequence was repeated generally every other Jupiter rotation, yielding views of every sector of the planet at least once every 20 hours.

    The images used for the movie shown here were taken every 20 hours through a filter centered at a wavelength of 756 nanometers, where there are almost no absorptions in the planet's atmosphere. Six images covering each rotation were mosaiced together to form a cylindrical map extending from 75 degrees north to 75 degrees south in latitude and covering 360 degrees in longitude. The movie consists of 84 such maps, spanning 70Earth days in time or 168 Jupiter rotations.

    For more information, see the Cassini Project home page, http://www.jpl.nasa.gov/cassini/ and the Cassini Imaging Team home page, http://ciclops.lpl.arizona.edu/ciclops/ .

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, manages the Cassini mission for NASA's Office of

  2. Jupiter in Color, by Cassini

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This color image of Jupiter was taken by the camera onboard NASA's Cassini spacecraft when it was 81.3 million kilometers (50.5 million miles) from the planet. It is composed of images taken in the blue, green, and red regions of the spectrum and is therefore close to the true color of Jupiter that one would see through an Earth-based telescope.

    The image is remarkably similar to images taken by NASA's Voyager 1 and 2 spacecraft more than 21 years ago, illustrating the stability of Jupiter's weather patterns. The parallel dark and bright bands and many other large-scale features are quasi-permanent structures that survive despite the intense small-scale activity ongoing in the atmosphere. The longevity of the large-scale features is an intrinsic property of the atmospheric flows on a gaseous planet such as Jupiter, with no solid surface. Smaller features, such as those in the dark bands north and south of the equator, are observed to form and disappear in a few days.

    Everything visible on the planet is a cloud. Unlike Earth, where only water condenses to form clouds, Jupiter has several cloud-forming substances in its atmosphere. The updrafts and downdrafts bring different mixtures of these substances up from below, leading to clouds of different colors. The bluish features just north of the equator are regions of reduced cloud cover, similar to the place where the Galileo atmospheric probe entered in 1995. They are called 'hot spots' because the reduced cloud cover allows heat to escape from warmer, deeper levels in the atmosphere.

    Jupiter's moon Europa is seen at the right, casting a shadow on the planet. Scientists believe Europa holds promise of a liquid ocean beneath its surface.

    Cassini is a cooperative project of NASA, the European Space Agency and the Italian Space Agency. The Jet Propulsion Laboratory, a division of the California Institute of Technology in Pasadena, Calif., manages the Cassini mission for NASA's Office of Space Science

  3. High Latitude Mottling on Jupiter

    NASA Technical Reports Server (NTRS)

    2000-01-01

    The familiar banded appearance of Jupiter at low and middle latitudes gradually gives way to a more mottled appearance at high latitudes in this striking true color image taken Dec. 13, 2000, by NASA's Cassini spacecraft.

    The intricate structures seen in the polar region are clouds of different chemical composition, height and thickness. Clouds are organized by winds, and the mottled appearance in the polar regions suggests more vortex-type motion and winds of less vigor at higher latitudes.

    The cause of this difference is not understood. One possible contributor is that the horizontal component of the Coriolis force, which arises from the planet's rotation and is responsible for curving the trajectories of ocean currents and winds on Earth, has its greatest effect at high latitudes and vanishes at the equator. This tends to create small, intense vortices at high latitudes on Jupiter. Another possibility may lie in that fact that Jupiter overall emits nearly as much of its own heat as it absorbs from the Sun, and this internal heat flux is very likely greater at the poles. This condition could lead to enhanced convection at the poles and more vortex-type structures. Further analysis of Cassini images, including analysis of sequences taken over a span of time, should help us understand the cause of equator-to-pole differences in cloud organization and evolution.

    By the time this picture was taken, Cassini had reached close enough to Jupiter to allow the spacecraft to return images with more detail than what's possible with the planetary camera on NASA's Earth-orbiting Hubble Space Telescope. The resolution here is 114 kilometers (71 miles) per pixel. This contrast-enhanced, edge-sharpened frame was composited from images take at different wavelengths with Cassini's narrow-angle camera, from a distance of 19 million kilometers (11.8 million miles). The spacecraft was in almost a direct line between the Sun and Jupiter, so the solar illumination on

  4. Jupiter - Io In Front of Jupiter Turbulent Clouds

    NASA Image and Video Library

    1996-11-13

    This photograph of the southern hemisphere of Jupiter was obtained by Voyager 2 on June 25, 1979, at a distance of 12 million kilometers (8 million miles). The Voyager spacecraft is rapidly nearing the giant planet, with closest approach to occur at 4:23 pm PDT on July 9. Seen in front of the turbulent clouds of the planet is Io, the innermost of the large Galilean satellites of Jupiter. Io is the size of our moon. Voyager discovered in early March that Io is the most volcanically active planetary body known in the solar system, with continuous eruptions much larger than any that take place on the Earth. The red, orange, and yellow colors of Io are thought to be deposits of sulfur and sulfur compounds produced in these eruptions. The smallest features in either Jupiter or Io that can be distinguished in this picture are about 200 kilometers (125 miles) across; this resolution, it is not yet possible to identify individual volcanic eruptions. Monitoring of the erupture activity of Io by Voyager 2 will begin about July 5 and will extend past the encounter July 9. http://photojournal.jpl.nasa.gov/catalog/PIA00371

  5. Hot Jupiters with companions: results of the long-term CORALIE survey

    NASA Astrophysics Data System (ADS)

    Neveu Van Malle, Marion; Queloz, Didier; Triaud, Amaury H. M. J.; Segransan, Damien; Udry, Stéphane; Pepe, Francesco

    2015-12-01

    For twenty years hot Jupiters have been challenging planet formation theories. While in-situ formation has rapidly been rejected, the giant planets migration mechanisms are still not well understood. Disc migration is probably the dominant scenario but it cannot explain the observed population of hot Jupiters. Dynamical models involving the influence of an additional planetary or stellar companion through scattering or Kozai-Lidov mechanisms could also explain planetary migration. Their role needs to be characterised.High eccentricity migration mechanisms are triggered by the presence of an additional object. Knutson et al. (2014) searched for planetary companions to hot Jupiters and deduced that half of them had a giant planetary companion.We have performed our own independent search for companions of hot Jupiters. Since 2007, we have monitored the Southern WASP confirmed planets with the high-resolution echelle spectrograph CORALIE. Our sample includes more than 100 targets, including 90 that have been followed for more than three years. Our results slightly differ from those of Knutson et al. (2014).I will present the results of this survey regarding the statistics of companions of hot Jupiters. I will compare our detections with the planetary occurrence rates as well as with the binary stars occurrence rates. I will describe the correlations between the presence of a companion and the properties of the hot Jupiter.

  6. On the two tales of Warm Jupiters

    NASA Astrophysics Data System (ADS)

    Huang, Chelsea; Wu, Yanqin

    2017-06-01

    Warm Jupiters often refer to giant planets with intermediate orbit periods between 10-200 days. Their period range corresponds to the so-called "period valley", the observed dip in occupation in-between the hot Jupiters and cold Jupiters. Observational evidences suggest that they are a distinct population from the hot Jupiters and are likely to be formed from at least two different channels themselves. Earlier radial velocity surveys show that at least a fraction of the warm Jupiters have modest to high eccentricities, supporting these planets migrate to their current location through either secular perturbations or planet-planet scatterings. On the other hand, transiting warm Jupiters found in Kepler are likely to have close-by transiting low mass companions interior/exterior to the warm Jupiter orbits. The existence of the companions indicating the system needs to be near coplanar, and near circular, unlike their radial velocity counter parts. In this talk, I will review observational properties to date of the warm Jupiters, as well as recent advances in the theory of the warm Jupiter formation. I will then discuss how new discoveries from TESS can help with understanding the transition between the hot and warm Jupiter population, and distinguish the contribution from different formation channels.

  7. MULTIPLE-PLANET SCATTERING AND THE ORIGIN OF HOT JUPITERS

    SciTech Connect

    Beauge, C.; Nesvorny, D.

    2012-06-01

    Doppler and transit observations of exoplanets show a pile-up of Jupiter-size planets in orbits with a 3 day period. A fraction of these hot Jupiters have retrograde orbits with respect to the parent star's rotation, as evidenced by the measurements of the Rossiter-McLaughlin effect. To explain these observations we performed a series of numerical integrations of planet scattering followed by the tidal circularization and migration of planets that evolved into highly eccentric orbits. We considered planetary systems having three and four planets initially placed in successive mean-motion resonances, although the angles were taken randomly to ensure orbital instability in short timescales. The simulations included the tidal and relativistic effects, and precession due to stellar oblateness. Our results show the formation of two distinct populations of hot Jupiters. The inner population (Population I) is characterized by semimajor axis a < 0.03 AU and mainly formed in the systems where no planetary ejections occurred. Our follow-up integrations showed that this population was transient, with most planets falling inside the Roche radius of the star in <1 Gyr. The outer population of hot Jupiters (Population II) formed in systems where at least one planet was ejected into interstellar space. This population survives the effects of tides over >1 Gyr and fits nicely the observed 3 day pile-up. A comparison between our three-planet and four-planet runs shows that the formation of hot Jupiters is more likely in systems with more initial planets. Due to the large-scale chaoticity that dominates the evolution, high eccentricities and/or high inclinations are generated mainly by close encounters between the planets and not by secular perturbations (Kozai or otherwise). The relative proportion of retrograde planets seems of be dependent on the stellar age. Both the distribution of almost aligned systems and the simulated 3 day pile-up also fit observations better in our four

  8. K2 Warm Jupiters with the LCOGT TECH team

    NASA Astrophysics Data System (ADS)

    Shporer, Avi; Bayliss, Daniel; Bento, Joao; Cochran, William D.; Colon, Knicole D.; Dragomir, Diana; Endl, Michael; Fulton, Benjamin James; Isaacson, Howard T.; Palle, Enric; Siverd, Robert; Vanderburg, Andrew; Zhou, George; LCOGT TECH Team

    2017-01-01

    Many if not most transiting gas giant planets on short orbital periods (so called hot Jupiters) have larger radii than theoretically expected. Although several explanations have been proposed, none have completely solved this puzzle. As the number of known transiting planets grew a correlation was identified between gas giant radius and the stellar incident flux. Still, it is not clear whether this correlation is causation. Several questions remain and answering them will characterize in more detail this observed correlation and in turn the process responsible for the inflated radii, such as: Is the lack of inflated gas giants at longer periods a robust feature? What is the incident flux below which there are no inflated gas giants? How low in incident flux does this correlation stretch? These questions arise since there are only a small number of transiting gas giants with low incident flux, below about 108 erg/s/cm2, corresponding to orbital periods beyond 10 days around a Sun-like host star. We refer to such gas giant planets as warm Jupiters. Discovering and confirming more transiting warm Jupiters is the goal of this project, undertaken by the LCOGT Transiting Exoplanet CHaracterization (TECH) team. We are using K2 as our main source of transiting warm Jupiter candidates, with a few candidates discovered in each K2 campaign. LCOGT telescopes are being used for obtaining additional ground-based transit light curves, which are critical for confirming and refining the K2 transit ephemeris as outliers during ingress or egress of the few transit events observed by K2 can bias the measured ephemeris. Further ground-based follow-up data, including spectroscopy, radial velocities, and high angular resolution imaging, are obtained by facilities directly accessible by LCOGT TECH team members. In addition, LCOGT’s Network of Robotic Echelle Spectrographs (NRES) will be deployed during 2017 and will allow obtaining spectroscopy and radial velocities with LCOGT

  9. K2 Warm Jupiters with the LCOGT TECH collaboration

    NASA Astrophysics Data System (ADS)

    Shporer, Avi; Bayliss, Daniel; Cochran, William D.; Colón, Knicole D.; Dragomir, Diana; Palle, Enric; Potter, Stephen; Siverd, Robert; LCOGT TECH Collaboration

    2016-06-01

    Many transiting gas giant planets on short orbital periods (so called hot Jupiters) have larger radii than theoretically expected. Although several explanations have been proposed, none have completely solved this puzzle. As the number of known transiting planets grew a correlation was identified between gas giant radius and the stellar incident flux. Still, it is not clear whether this correlation is causation. Several questions remain and answering them will characterize in more detail this observed correlation and in turn the process responsible for the inflated radii, such as: Is the lack of inflated warm Jupiters a robust feature? What is the incident flux below which there are no inflated gas giants? How low in incident flux does this correlation stretch? These questions arise since there are only a small number of transiting gas giants with low incident flux, below about 108 erg/s/cm2, corresponding to orbital periods of about 10 days and longer for a Sun-like host star. Discovering and confirming more transiting warm Jupiters is the goal of this project, undertaken by the LCOGT Transiting Exoplanet CHaracterization (TECH) team. We are using K2 as our main source of transiting warm Jupiter candidates, with a few candidates discovered in each K2 campaign. LCOGT telescopes are being used for obtaining additional ground-based transit light curves, which are critical for confirming and refining the K2 transit ephemeris as outliers during ingress or egress of the few transit events observed by K2 can bias the measured ephemeris. Further ground-based follow-up data, including spectroscopy, radial velocities, and high angular resolution imaging, are obtained by facilities directly accessible by LCOGT TECH team members. In addition, once LCOGT’s Network of Robotic Echelle Spectrographs (NRES) are deployed in the near future they will allow obtaining spectroscopy and radial velocities with LCOGT facilities. On top of studying the inflated hot Jupiter conundrum

  10. Jupiter's Clouds of Many Colors

    NASA Image and Video Library

    2017-06-15

    NASA's Juno spacecraft was racing away from Jupiter following its seventh close pass of the planet when JunoCam snapped this image on May 19, 2017, from about 29,100 miles (46,900 kilometers) above the cloud tops. The spacecraft was over 65.9 degrees south latitude, with a lovely view of the south polar region of the planet. This image was processed to enhance color differences, showing the amazing variety in Jupiter's stormy atmosphere. The result is a surreal world of vibrant color, clarity and contrast. Four of the white oval storms known as the "String of Pearls" are visible near the top of the image. Interestingly, one orange-colored storm can be seen at the belt-zone boundary, while other storms are more of a cream color. https://photojournal.jpl.nasa.gov/catalog/PIA21392

  11. Cold Hole Over Jupiter's Pole

    NASA Technical Reports Server (NTRS)

    2002-01-01

    Observations with two NASA telescopes show that Jupiter has an arctic polar vortex similar to a vortex over Earth's Antarctica that enables depletion of Earth's stratospheric ozone.

    These composite images of Jupiter's north polar region from the Hubble Space Telescope (right) and the Infrared Telescope Facility (left) show a quasi-hexagonal shape that extends vertically from the stratosphere down into the top of the troposphere. A sharp temperature drop, compared to surrounding air masses, creates an eastward wind that tends to keep the polar atmosphere, including the stratospheric haze, isolated from the rest of the atmosphere.

    The linear striations in the composite projections are artifacts of the image processing. The area closest to the pole has been omitted because it was too close to the edge of the planet in the original images to represent the planet reliably.

    The composite on the right combines images from the Wide Field and Planetary Camera 2 of the Hubble Space Telescope taken at a wavelength of 890 nanometers, which shows stratospheric haze particles.

    The sharp boundary and wave-like structure of the haze layer suggest a polar vortex and a similarity to Earth's stratospheric polar clouds. Images of Jupiter's thermal radiation clinch that identification. The composite on the left, for example, is made from images taken with Jet Propulsion Laboratory's Mid-Infrared Large-Well Imager at NASA's Infrared Telescope Facility at a wavelength of 17 microns. It shows polar air mass that is 5 to 6 degrees Celsius (9 to 10 degrees Fahrenheit) colder than its surroundings, with the same border as the stratospheric haze. Similar observations at other infrared wavelengths show the cold air mass extends at least as high as the middle stratosphere down to the top of the troposphere.

    These images were taken Aug. 11 through Aug. 13, 1999, near a time when Jupiter's north pole was most visible from Earth. Other Infrared Telescope Facility images at

  12. Jupiter's magnetic tail: Voyager 1

    NASA Technical Reports Server (NTRS)

    Ness, N. F.; Acuna, M. H.; Lepping, R. P.; Behannon, K. W.; Burlaga, L. F.; Neubauer, F. M.

    1979-01-01

    Magnetic field observations by the Voyager 1 spacecraft during the outbound traversal of the Jovian magnetosphere in March 1979 suggest the detection of an extended magnetic tail, which has been formed by the solar wind interaction with the planetary field. The apparent diameter of the tail is 300-400 times the radius of Jupiter but its length is not measured. When combined with the GSFC O4 model of the planetary field, this magnetosphere topology leads to polar cap auroral zones approximately 20 deg in diameter, considerably smaller than earth's. The northern zone is found to be highly eccentric, encircling neither the rotational pole nor the magnetic pole of Jupiter, and limited to System III (1965) longitudes approximately 133 deg to 190 deg and latitudes approximately 62 deg to 82 deg.

  13. Clouds on Hot Jupiters Illustration

    NASA Image and Video Library

    2016-10-18

    Hot Jupiters are exoplanets that orbit their stars so tightly that their temperatures are extremely high, reaching over 2,400 degrees Fahrenheit (1600 Kelvin). They are also tidally locked, so one side of the planet always faces the sun and the other is in permanent darkness. Research suggests that the "dayside" is largely free of clouds, while the "nightside" is heavily clouded. This illustration represents how hot Jupiters of different temperatures and different cloud compositions might appear to a person flying over the dayside of these planets on a spaceship, based on computer modeling. Cooler planets are entirely cloudy, whereas hotter planets have morning clouds only. Clouds of different composition have different colors, whereas the clear sky is bluer than on Earth. For the hottest planets, the atmosphere is hot enough on the evening side to glow like a charcoal. Figure 1 shows an approximation of what various hot Jupiters might look like based on a combination of computer modeling and data from NASA's Kepler Space Telescope. From left to right it shows: sodium sulfide clouds (1000 to 1200 Kelvin), manganese sulfide clouds (1200 to 1600 Kelvin), magnesium silicate clouds (1600 to 1800 Kelvin), magnesium silicate and aluminum oxide clouds (1800 Kelvin) and clouds composed of magnesium silicate, aluminum oxide, iron and calcium titanate (1900 to 2200 Kelvin). http://photojournal.jpl.nasa.gov/catalog/PIA21074

  14. Ammonia Ice Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The top cloud layer on Jupiter is thought to consist of ammonia ice, but most of that ammonia 'hides' from spectrometers. It does not absorb light in the same way ammonia does. To many scientists, this implies that ammonia churned up from lower layers of the atmosphere 'ages' in some way after it condenses, possibly by being covered with a photochemically generated hydrocarbon mixture. The New Horizons Linear Etalon Imaging Spectral Array (LEISA), the half of the Ralph instrument that is able to 'see' in infrared wavelengths that are absorbed by ammonia ice, spotted these clouds and watched them evolve over five Jupiter days (about 40 Earth hours). In these images, spectroscopically identified fresh ammonia clouds are shown in bright blue. The largest cloud appeared as a localized source on day 1, intensified and broadened on day 2, became more diffuse on days 3 and 4, and disappeared on day 5. The diffusion seemed to follow the movement of a dark spot along the boundary of the oval region. Because the source of this ammonia lies deeper than the cloud, images like these can tell scientists much about the dynamics and heat conduction in Jupiter's lower atmosphere.

  15. Ammonia Ice Clouds on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The top cloud layer on Jupiter is thought to consist of ammonia ice, but most of that ammonia 'hides' from spectrometers. It does not absorb light in the same way ammonia does. To many scientists, this implies that ammonia churned up from lower layers of the atmosphere 'ages' in some way after it condenses, possibly by being covered with a photochemically generated hydrocarbon mixture. The New Horizons Linear Etalon Imaging Spectral Array (LEISA), the half of the Ralph instrument that is able to 'see' in infrared wavelengths that are absorbed by ammonia ice, spotted these clouds and watched them evolve over five Jupiter days (about 40 Earth hours). In these images, spectroscopically identified fresh ammonia clouds are shown in bright blue. The largest cloud appeared as a localized source on day 1, intensified and broadened on day 2, became more diffuse on days 3 and 4, and disappeared on day 5. The diffusion seemed to follow the movement of a dark spot along the boundary of the oval region. Because the source of this ammonia lies deeper than the cloud, images like these can tell scientists much about the dynamics and heat conduction in Jupiter's lower atmosphere.

  16. Pressure anisotropy in Jupiter's magnetodisc

    NASA Astrophysics Data System (ADS)

    Nichols, J. D.; Achilleos, N.; Cowley, S. W. H.

    2013-09-01

    The magnetosphere-ionosphere coupling current system at Jupiter has been studied by a number of authors over the last decade. Until recently, however, the various modelling studies treated the magnetic field as an empirically-based input derived from Voyager observations. This limitation was removed by Nichols (2011), who employed a self-consistent field model calculated using force-balance between the outward plasma pressure gradients plus the centrifugal force of the rotating iogenic plasma, and the inward JxB force arising from the azimuthal current sheet. However, the above study, which incorporated the magnetic field model of Caudal (1983), employed isotropic plasma pressure, whereas it is known that anisotropic plasma pressure plays a key role in the stress balance at Jupiter (e.g. Paranicas et al., 1991). In this paper we generalise the computation to include anisotropic pressure, and compute the magnetic field by summing over elliptical integrals. We then calculate the magnetosphere-ionosphere coupling currents assuming an equatorial parallel-to-perpendicular pressure ratio of 1.14, the value determined by Paranicas et al. (1991), and we also consider the effect on the system of solar wind-induced compression events. We find that the anisotropy current dominates the current sheet in the middle magnetosphere between 20-40RJ, and that Jupiter's magnetosphere is susceptible to the firehose instability.

  17. D-D Fusion in the Interior of Jupiter?

    NASA Astrophysics Data System (ADS)

    Ouyed, Rachid; Fundamenski, Wojciech R.; Cripps, Gregory R.; Sutherland, Peter G.

    1998-07-01

    One of the still uncertain and debated questions about Jupiter is the origin of its excess heat. Understanding the source of such heat will certainly shed some light on the physics of the interior of the planet and on scenarios of its formation. Recent measurements of sound velocities in Jupiter show substantial disagreement with the existing models for the Jovian interior. Analysis of these measurements suggests that helium (He) sedimentation (through H-He phase separation) is plausible in the planet's interior, contrary to what is believed from numerical calculations of H-He mixture at conditions prevailing in Jupiter's deep interior. This signals the need for a revision of the existing models of Jupiter and allows for new models to be explored. While He sedimentation might help shift the calculated sound velocities toward the observed ones, we find that it cannot explain the excess heat. Here, we analyze the consequences of deuterium (D) sedimentation on Jupiter's excess heat and discuss its effects on the sound profiles. Such a sedimentation is assumed to have occurred in the early stages of planet formation (here the core-instability model) through planetesimal vaporization in the deeper parts of the envelope. Our interest in investigating D sedimentation resulted from the recent extrapolations of D-D, D-T, D-3He, and p-D fusion to electron volt temperatures, which indicate that D-D fusion largely dominates the other reactions under conditions thought to prevail in the interior of early Jupiter. We find that with a modest degree of interior stratification of D (5%-15% of the total D of the planet), D-D burning naturally explains the excess heat given off by the planet. For our model to operate, we find that D sedimentation must occur during the early stages of planet formation (core-instability scenario) when interior temperatures of 16-18 eV where available. Our model is applied to the family of the Jovian planets as a whole.

  18. First look at Jupiter's synchrotron emission from Juno's perspective

    NASA Astrophysics Data System (ADS)

    Santos-Costa, D.; Adumitroaie, V.; Ingersoll, A.; Gulkis, S.; Janssen, M. A.; Levin, S. M.; Oyafuso, F.; Brown, S.; Williamson, R.; Bolton, S. J.; Connerney, J. E. P.

    2017-09-01

    Since August 2016, measurements of Jupiter's microwave emissions at six wavelengths ranging from 1.3 cm to 50 cm have been made with the Juno Microwave Radiometer. In this paper, we introduce the first systematic set of in situ observations of synchrotron radiation in a polar plane while describing the modeling approach we use to analyze this data (collected 27 August 2016). Time series of brightness profiles at all six frequencies present similarities that are explained by the presence of known regions of intense synchrotron radiation. Our model predictions, though limited for now to the total intensity of the radiation, reproduce (qualitatively) the observation of temporal variations and allow to disentangle the synchrotron emission from the atmospheric emission. The discrepancies seen between the data and simulations confirm that physical conditions close to Jupiter affecting synchrotron emission (electron energy spectra, pitch angle distributions, and the magnetic environment) are different than we anticipated.

  19. Solar wind collimation of the Jupiter high velocity dust streams

    NASA Astrophysics Data System (ADS)

    Flandes, A.; Krueger, H.

    2006-12-01

    The dust bursts discovered by the Ulysses dust sensor when approaching Jupiter in 1992 were later confirmed as collimated streams of high velocity (~200 km/s) charged (~5V) dust grains escaping from Jupiter and dominated by the interplanetary Magnetic field (IMF). With Cassini, a similar phenomenon was observed in Saturn. It was demonstrated that the Jovian dust streams are closely related to the solar wind compressed regions, either Corotating interaction regions (CIRs) or Coronal mass ejections (CMEs) ¨Cto a minor extent-. Actually the dust streams seem ultimately to be generated by such events. This can be explained considering that dust grains are accelerated as they gain substantial energy while compressed at the forward and reverse shocks that bound or precede these solar wind regions.

  20. HOT STARS WITH HOT JUPITERS HAVE HIGH OBLIQUITIES

    SciTech Connect

    Winn, Joshua N.; Albrecht, Simon; Fabrycky, Daniel; Johnson, John Asher

    2010-08-01

    We show that stars with transiting planets for which the stellar obliquity is large are preferentially hot (T{sub eff} > 6250 K). This could explain why small obliquities were observed in the earliest measurements, which focused on relatively cool stars drawn from Doppler surveys, as opposed to hotter stars that emerged more recently from transit surveys. The observed trend could be due to differences in planet formation and migration around stars of varying mass. Alternatively, we speculate that hot-Jupiter systems begin with a wide range of obliquities, but the photospheres of cool stars realign with the orbits due to tidal dissipation in their convective zones, while hot stars cannot realign because of their thinner convective zones. This in turn would suggest that hot Jupiters originate from few-body gravitational dynamics and that disk migration plays at most a supporting role.

  1. Variability of Jupiter's IR H3+ aurorae during Juno approach

    NASA Astrophysics Data System (ADS)

    Moore, L.; O'Donoghue, J.; Melin, H.; Stallard, T.; Tao, C.; Zieger, B.; Clarke, J.; Vogt, M. F.; Bhakyapaibul, T.; Opher, M.; Tóth, G.; Connerney, J. E. P.; Levin, S.; Bolton, S.

    2017-05-01

    We present ground-based observations of Jupiter's H3+ aurorae over four nights in April 2016 while the Juno spacecraft was monitoring the upstream interplanetary magnetic field. High-precision maps of auroral H3+ densities, temperatures, and radiances reveal significant variabilities in those parameters, with regions of enhanced density and emission accompanied by reduced temperature. Juno magnetometer data, combined with solar wind propagation models, suggest that a shock may have impacted Jupiter in the days preceding the observation interval but that the solar wind was quiescent thereafter. Auroral H3+ temperatures reveal a downward temporal trend, consistent with a slowly cooling upper atmosphere, such as might follow a period of shock recovery. The brightest H3+ emissions are from the end of the period, 23 April. A lack of definitive signatures in the upstream interplanetary magnetic field lends supporting evidence to the possibility that this brightening event may have been driven by internal magnetospheric processes.

  2. Artist: Ken Hodges Composite image explaining Objective and Motivation for Galileo Probe Heat Loads:

    NASA Technical Reports Server (NTRS)

    1981-01-01

    Artist: Ken Hodges Composite image explaining Objective and Motivation for Galileo Probe Heat Loads: Galileo Probe descending into Jupiters Atmosphere shows heat shield separation with parachute deployed. (Ref. JPL P-19180)

  3. VLA Will Receive Galileo Probe Signals To Measure Jupiter's Winds

    NASA Astrophysics Data System (ADS)

    1995-11-01

    Socorro, NM -- When the Galileo Probe becomes the first spacecraft to enter the atmosphere of Jupiter on Dec. 7, a New Mexico radio telescope will be watching. In a technical feat thought impossible when Galileo was launched in 1989, the National Science Foundation's Very Large Array (VLA) will record the faint radio signal from the probe to help scientists measure the giant planet's winds. The VLA observations will dramatically improve estimates of Jupiter's wind speeds and complement other measurements studying the climate of Jupiter. The Galileo probe will transmit information to the main spacecraft as it descends toward a searing death under tremendous heat in Jupiter's lower atmosphere. The main spacecraft will later relay the probe's data to Earth. No Earth-based reception of the probe's radio signals was planned originally. The probe's antenna will be pointed at the main spacecraft, not the Earth. However, in 1991, Robert Preston and William Folkner of NASA's Jet Propulsion Laboratory (JPL) in Pasadena, CA, were discussing Earth-based reception of data from a similar probe under design for a planned mission to Saturn. "I thought, why not do this for Galileo," Folkner said. "They were planning to build this capability into the spacecraft for Saturn," Folkner explained, "and they thought it couldn't be done with the Galileo spacecraft already enroute to Jupiter. I didn't know it couldn't be done, so I worked it out and found that we could do it." According to Preston and Folkner's calculations, the direct reception of the probe's signals by the VLA and a similar radio telescope in Australia will make the measurement of Jupiter's winds ten times more precise as long as the probe radio signal can be detected. In addition, the direct reception also greatly improves scientists' knowledge of the probe's position as it enters the Jovian atmosphere. This will allow more effective use of the measurements of the probe radio signal by the main spacecraft to determine

  4. Considerations on the Outward Migration of Jupiter and Saturn

    NASA Astrophysics Data System (ADS)

    D'Angelo, G.; Marzari, F.

    2011-12-01

    It has been proposed that the outward orbital migration of Jupiter and Saturn, driven by a gas-dominated protosolar disk, may help explain why they did not move much closer to the Sun. It has also been suggested that some properties of the inner Solar System may be interpreted by invoking an inward migration of Jupiter and Saturn followed by outward migration, once they get caught in the 2:3 mean motion resonance. Hydrodynamical calculations indicate that outward migration of a compact Jupiter-Saturn system may arise from an imbalance between positive and negative Lindblad torques exerted on Jupiter by the disk. The torque density distribution acting on Jupiter extends over ~3 Hill radii on either side of the planet's orbit. The negative part of the distribution samples outer disk portions, partially depleted by the tidal perturbations of both planets. The positive part of the distribution samples inner disk portions, depleted only by the action of Jupiter. The net result may be a positive torque exerted on Jupiter. Saturn, trapped in resonance with Jupiter, migrates outward as well. This mechanism requires the exterior planet's mass not to exceed the interior planet's mass. Thus, it is assumed that neither planet accretes gas from the disk. Yet, models of giant planet formation indicate that these planets would accrete gas at whatever rate the disk provides (Lissauer et al., 2009, Icarus, 199, 338). We performed 2D and 3D hydrodynamical calculations of a Jupiter-Saturn system tidally interacting with a protoplanetary disk and investigated how gas accretion affects their migration history. We assumed initial conditions shown to result in the outward migration of non-accreting planets and recovered such scenario. We then allowed the planets to accrete gas at a disk-limited rate. In agreement with estimates derived for single planets, the assumed disk conditions lead to a mass-doubling time scale of the exterior planet that is 6-9 times as short as that of interior

  5. Jupiter C/Explorer 1 in Gantry

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Explorer 1 atop a Jupiter-C in gantry. Jupiter-C carrying the first American satellite, Explorer 1, was successfully launched on January 31, 1958. The Jupiter-C launch vehicle consisted of a modified version of the Redstone rocket's first stage and two upper stages of clustered Baby Sergeant rockets developed by the Jet Propulsion Laboratory and later designated as Juno boosters for space launches

  6. Jupiter C/Explorer 1 in Gantry

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Explorer 1 atop a Jupiter-C in gantry. Jupiter-C carrying the first American satellite, Explorer 1, was successfully launched on January 31, 1958. The Jupiter-C launch vehicle consisted of a modified version of the Redstone rocket's first stage and two upper stages of clustered Baby Sergeant rockets developed by the Jet Propulsion Laboratory and later designated as Juno boosters for space launches

  7. RE-INFLATED WARM JUPITERS AROUND RED GIANTS

    SciTech Connect

    Lopez, Eric D.; Fortney, Jonathan J.

    2016-02-10

    Since the discovery of the first transiting hot Jupiters, models have sought to explain the anomalously large radii of highly irradiated gas giants. We now know that the size of hot Jupiter radius anomalies scales strongly with a planet's level of irradiation and numerous models like tidal heating, ohmic dissipation, and thermal tides have since been developed to help explain these inflated radii. In general, however, these models can be grouped into two broad categories: models that directly inflate planetary radii by depositing a fraction of the incident irradiation into the interior and models that simply slow a planet's radiative cooling, allowing it to retain more heat from formation and thereby delay contraction. Here we present a new test to distinguish between these two classes of models. Gas giants orbiting at moderate orbital periods around post-main-sequence stars will experience enormous increases to their irradiation as their host stars move up the sub-giant and red-giant branches. If hot Jupiter inflation works by depositing irradiation into the planet's deep interiors then planetary radii should increase in response to the increased irradiation. This means that otherwise non-inflated gas giants at moderate orbital periods of >10 days can re-inflate as their host stars evolve. Here we explore the circumstances that can lead to the creation of these “re-inflated” gas giants and examine how the existence or absence of such planets can be used to place unique constraints on the physics of the hot Jupiter inflation mechanism. Finally, we explore the prospects for detecting this potentially important undiscovered population of planets.

  8. Two Moons Meet over Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This beautiful image of the crescents of volcanic Io and more sedate Europa was snapped by New Horizons' color Multispectral Visual Imaging Camera (MVIC) at 10:34 UT on March 2, 2007, about two days after New Horizons made its closest approach to Jupiter.

    The picture was one of a handful of the Jupiter system that New Horizons took primarily for their artistic, rather than scientific value. This particular scene was suggested by space enthusiast Richard Hendricks of Austin, Texas, in response to an Internet request by New Horizons scientists for evocative, artistic imaging opportunities at Jupiter.

    This image was taken from a range of 4.6 million kilometers (2.8 million miles) from Io and 3.8 million kilometers (2.4 million miles) from Europa. Although the moons appear close in this view, a gulf of 790,000 kilometers (490,000 miles) separates them. The night side of Io is illuminated here by light reflected from Jupiter, which is out of the frame to the right. Europa's night side is completely dark, in contrast to Io, because that side of Europa faces away from Jupiter.

    Here, Io steals the show with its beautiful display of volcanic activity. Three volcanic plumes are visible. Most conspicuous is the enormous 300-kilometer (190-mile) -high plume from the Tvashtar volcano at the 11 o'clock position on Io's disk. Two much smaller plumes are barely visible: one from the volcano Prometheus, at the 9 o'clock position on the edge of Io's disk, and one from the volcano Amirani, seen between Prometheus and Tvashtar along Io's terminator (the line dividing day and night). The plumes appear blue because of the scattering of light by tiny dust particles ejected by the volcanoes, similar to the blue appearance of smoke. In addition, the contrasting red glow of hot lava can be seen at the source of the Tvashtar plume.

    The images are centered at 1 degree north, 60 degrees west on Io, and 0 degrees north, 149 degrees west on Europa. The color in this

  9. Two Moons Meet over Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    This beautiful image of the crescents of volcanic Io and more sedate Europa was snapped by New Horizons' color Multispectral Visual Imaging Camera (MVIC) at 10:34 UT on March 2, 2007, about two days after New Horizons made its closest approach to Jupiter.

    The picture was one of a handful of the Jupiter system that New Horizons took primarily for their artistic, rather than scientific value. This particular scene was suggested by space enthusiast Richard Hendricks of Austin, Texas, in response to an Internet request by New Horizons scientists for evocative, artistic imaging opportunities at Jupiter.

    This image was taken from a range of 4.6 million kilometers (2.8 million miles) from Io and 3.8 million kilometers (2.4 million miles) from Europa. Although the moons appear close in this view, a gulf of 790,000 kilometers (490,000 miles) separates them. The night side of Io is illuminated here by light reflected from Jupiter, which is out of the frame to the right. Europa's night side is completely dark, in contrast to Io, because that side of Europa faces away from Jupiter.

    Here, Io steals the show with its beautiful display of volcanic activity. Three volcanic plumes are visible. Most conspicuous is the enormous 300-kilometer (190-mile) -high plume from the Tvashtar volcano at the 11 o'clock position on Io's disk. Two much smaller plumes are barely visible: one from the volcano Prometheus, at the 9 o'clock position on the edge of Io's disk, and one from the volcano Amirani, seen between Prometheus and Tvashtar along Io's terminator (the line dividing day and night). The plumes appear blue because of the scattering of light by tiny dust particles ejected by the volcanoes, similar to the blue appearance of smoke. In addition, the contrasting red glow of hot lava can be seen at the source of the Tvashtar plume.

    The images are centered at 1 degree north, 60 degrees west on Io, and 0 degrees north, 149 degrees west on Europa. The color in this

  10. Probing Storm Activity on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Scientists assume Jupiter's clouds are composed primarily of ammonia, but only about 1% of the cloud area displays the characteristic spectral fingerprint of ammonia. This composite of infrared images taken by the New Horizons Linear Etalon Infrared Spectral Imager (LEISA) captures several eruptions of this relatively rare breed of ammonia cloud and follows the evolution of the clouds over two Jovian days. (One day on Jupiter is approximately 10 hours, which is how long it takes Jupiter to make one complete rotation about its axis.)

    The New Horizons spacecraft was still closing in on the giant planet when it made these observations: Jupiter was 3.4 million kilometers (2.1 million miles) from the New Horizons spacecraft for the LEISA image taken at 19:35 Universal Time on February 26, 2007, and the distance decreased to 2.5 million kilometers (1.6 million miles) for the last image shown. LEISA's spatial resolution scale varied from approximately 210 kilometers (130 miles) for the first image to 160 kilometers (100 miles) for the last one.

    New Horizons scientists originally targeted the region slightly northwest (up and to the left) of the Great Red Spot to search for these special ammonia clouds because that's where they were most easily seen during infrared spectral observations made by the Galileo spacecraft. But unlike the churning, turbulent cloud structures seen near the Great Red Spot during the Galileo era, this region has been quieting down during the past several months and was unusually tranquil when New Horizons passed by. Nevertheless, LEISA managed to find other regions of fresh, upwelling ammonia clouds, and the temporal evolution of one such region is displayed in this figure. In the first image, a fresh ammonia cloud (the blue region) sprouts from between white clouds and a dark elongated region. This blue cloud subsequently stretches along the white-dark border in the next two images.

    These fresh ammonia clouds trace the strong

  11. Probing Storm Activity on Jupiter

    NASA Technical Reports Server (NTRS)

    2007-01-01

    Scientists assume Jupiter's clouds are composed primarily of ammonia, but only about 1% of the cloud area displays the characteristic spectral fingerprint of ammonia. This composite of infrared images taken by the New Horizons Linear Etalon Infrared Spectral Imager (LEISA) captures several eruptions of this relatively rare breed of ammonia cloud and follows the evolution of the clouds over two Jovian days. (One day on Jupiter is approximately 10 hours, which is how long it takes Jupiter to make one complete rotation about its axis.)

    The New Horizons spacecraft was still closing in on the giant planet when it made these observations: Jupiter was 3.4 million kilometers (2.1 million miles) from the New Horizons spacecraft for the LEISA image taken at 19:35 Universal Time on February 26, 2007, and the distance decreased to 2.5 million kilometers (1.6 million miles) for the last image shown. LEISA's spatial resolution scale varied from approximately 210 kilometers (130 miles) for the first image to 160 kilometers (100 miles) for the last one.

    New Horizons scientists originally targeted the region slightly northwest (up and to the left) of the Great Red Spot to search for these special ammonia clouds because that's where they were most easily seen during infrared spectral observations made by the Galileo spacecraft. But unlike the churning, turbulent cloud structures seen near the Great Red Spot during the Galileo era, this region has been quieting down during the past several months and was unusually tranquil when New Horizons passed by. Nevertheless, LEISA managed to find other regions of fresh, upwelling ammonia clouds, and the temporal evolution of one such region is displayed in this figure. In the first image, a fresh ammonia cloud (the blue region) sprouts from between white clouds and a dark elongated region. This blue cloud subsequently stretches along the white-dark border in the next two images.

    These fresh ammonia clouds trace the strong

  12. On limits to Jupiter's magnetospheric diffusion rates.

    NASA Technical Reports Server (NTRS)

    Mihalov, J. D.

    1973-01-01

    X-ray fluxes at earth estimated from hypothetical fluxes and spectra of energetic particles trapped in Jupiter's magnetic field are found to be 1/170000 times the upper limit X-ray flux from Jupiter based on published results from a rocket experiment. Detection of the calculated X-ray flux from Jupiter does not necessarily provide information on an energetic trapped proton component because the X-ray flux due to the hypothetical trapped energetic proton fluxes alone is comparable in magnitude to that due alone to trapped energetic electron fluxes as Jupiter.

  13. On limits to Jupiter's magnetospheric diffusion rates.

    NASA Technical Reports Server (NTRS)

    Mihalov, J. D.

    1973-01-01

    X-ray fluxes at earth estimated from hypothetical fluxes and spectra of energetic particles trapped in Jupiter's magnetic field are found to be 1/170000 times the upper limit X-ray flux from Jupiter based on published results from a rocket experiment. Detection of the calculated X-ray flux from Jupiter does not necessarily provide information on an energetic trapped proton component because the X-ray flux due to the hypothetical trapped energetic proton fluxes alone is comparable in magnitude to that due alone to trapped energetic electron fluxes as Jupiter.

  14. Juno at Jupiter: Mission and Science

    NASA Astrophysics Data System (ADS)

    Bolton, Scott

    2016-07-01

    The Juno mission is the second mission in NASA's New Frontiers program. Launched in August 2011, Juno arrives at Jupiter in July 2016. Juno science goals include the study of Jupiter's origin, interior structure, deep atmosphere, aurora and magnetosphere. Jupiter's formation is fundamental to the evolution of our solar system and to the distribution of volatiles early in the solar system's history. Juno's measurements of the abundance of Oxygen and Nitrogen in Jupiter's atmosphere, and the detailed maps of Jupiter's gravity and magnetic field structure will constrain theories of early planetary development. Juno's orbit around Jupiter is a polar elliptical orbit with perijove approximately 5000 km above the visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, electric and magnetic field radio and plasma wave experiment, ultraviolet imaging spectrograph, infrared imager and a visible camera. The Juno design enables the first detailed investigation of Jupiter's interior structure, and deep atmosphere as well as the first in depth exploration of Jupiter's polar magnetosphere. The Juno mission design, science goals, and measurements related to the atmosphere of Jupiter will be presented.

  15. A Model of Jupiter's Decametric Radio Emissions as a Searchlight Beam

    NASA Astrophysics Data System (ADS)

    Imai, K.; Garcia, L.; Reyes, F.; Imai, M.; Thieman, J. R.

    It has long been recognized that there is a marked long-term periodic variation in Jupiter's integrated radio occurrence probability. The period of the variation is on the order of a decade. Carr et al. [1970] showed that such variations are closely correlated with Jovicentric declination of the Earth (DE). The range of the smoothed variation of DE is from approximately +3.3 to -3.3 degrees. This DE effect was extensively studied and confirmed by Garcia [1996]. It shows that the occurrence probability of the non-Io-A source is clearly controlled by DE at 18, 20, and 22 MHz during the 1957-1994 apparitions. We propose a new model to explain the DE effect. This new model shows that the beam structure of Jupiter radio emissions, which has been thought of like a hollow-cone, has a narrow beam like a searchlight, which can be explained by assuming that the three dimensional shape of the radio source expands along the line of the magnetic field. If we consider the sizes of the radio coherent region are 1000 m along Jupiter's magnetic field line and 200 m along the latitudinal direction, the equivalent beam pattern is 1 degree wide along Jupiter's magnetic field line and 5 degrees in latitude. As the searchlight beam is fixed with Jupiter's magnetic field, the pure geometrical effect of DE can be explained by this searchlight beam model.

  16. Structure and Evolution of Internally Heated Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Youdin, Andrew N.

    2015-11-01

    The transit radii of many close-in extrasolar giant planets, or "hot Jupiters," are systematically larger than those expected from models considering only cooling from an initial high-entropy state. Though these planets receive strong irradiation, with equilibrium temperatures of 1000-2500 Kelvin, the absorption of stellar incident flux in the upper atmosphere alone cannot explain these anomalous radii. More promising mechanisms involve irradiation-driven meteorological activity, which penetrates much deeper into the planet than direct stellar heating. This circulation can lead to large-scale mixing and downward transport of kinetic energy, both processes whereby a fraction of the stellar incident power is transported downwards to the interior of the planet. Here we consider how deposition of heat at different pressure levels or structural locations within a planet affects the resulting evolution. To do so, we run global gas giant evolutionary models with with the stellar structure code MESA including additional energy dissipation. We find that relatively shallow atmospheric heating alone can explain the transit radii of the hot Jupiter sample, but heating in the convective zone is an order of magnitude more efficient regardless of exact location. Additionally, a small difference in atmospheric heating location can have a significant effect on radius evolution, especially near the radiative-convective boundary. The most efficient location to heat the planet is at the radiative-convective boundary or deeper. We expect that shear instabilities at this interface may naturally explain energy dissipation at the radiative-convective boundary, which typically lies at a pressure of ~1 kilobar after 5 Gyr for a planet with the mass and incident stellar flux of HD 209458b. Hence, atmospheric processes are most efficient at explaining the bloated radii of hot Jupiters if they can transport incident stellar power downwards to the top of the inner convective zone.

  17. The EJSM Jupiter-Ganymede Orbiter

    NASA Astrophysics Data System (ADS)

    Blanc, M.; Lebreton, J.-P.; Stankov, A.; Greeley, R.; Pappalardo, R. T.; Fujimoto, M.

    2008-09-01

    The Europa-Jupiter System Mission (EJSM), currently subject of a joint study by NASA, ESA and JAXA, would combine a fleet of three satellites in order to investigate in depth many questions related to the Jupiter System. These investigations are essential for our understanding of the emergence and evolution of habitable worlds, not only within the Solar System, but also for extrasolar planet investigations. Scientific targets of EJSM focus on Europa and Ganymede as a key pair of Galilean satellites, to address the questions on their habitability, formation, and internal structure, as well as the coupling with the whole Jovian system: Jupiter's atmosphere and interior, magnetosphere and magnetodisk.. In combination with a Jupiter Europa Orbiter (JEO that would be provided by NASA) and a Jupiter Magnetospheric Orbiter (JMO that would be provided by JAXA), ESA is studying a Jupiter Ganymede Orbiter (JGO). The mission scenario includes a launch in 2020 with a transfer time to Jupiter of ~6 years. After the orbit insertion around Jupiter, a first phase (~2 years) will be devoted to Jupiter system and Callisto studies, with multiple flybys of Callisto planned at low altitude (~200 km), followed by a Ganymede orbit insertion and extensive study of Ganymede (~1 year). In depth comparative study of inner (Io and Europe) and outer (Ganymede and Callisto) satellites with combined payload of JEO and JGO will address the question of the geologic relative evolution of the satellites. On JGO, the transport phenomena in the magnetosphere of Jupiter will be studied in combination with JMO, and the Ganymede magnetosphere will be observed in situ. Jupiter atmosphere investigations on JGO will focus on coupling phenomena between troposphere, stratosphere and mesosphere, the stratospheric composition and the question of thermospheric heating.

  18. Radial diffusion models of energetic electrons and Jupiter's synchrotron radiation. 2: Time variability

    NASA Astrophysics Data System (ADS)

    de Pater, I.

    1994-02-01

    We used a radial diffusion code for energetic electrons in Jupiter's magnetosphere to investigate variations in Jupiter's radio emission due to changes in the electron phase space density at L shells between 6 and 50, and due to changes in the radial diffusion parameters. We suggest that the observed variations in Jupiter's radio emission are likely caused by changes in the electron phase space density at some boundary L1 is greater than 6, if the primary mode of transport of energetic electrons is radial diffusion driven by fluctuating electric and/or magnetic fields induced by upper atmospheric turbulence. We noticed an excellent empirical correlation, both in phase and relative amplitude, between changes in the solar wind ram pressure and Jupiter's synchrotron radiation if the electron phase space density at the boundary L1 (L1 is approximately equal to 20-50) varies linearly with the square root of the solar wind ram pressure, f is approximately (Nsnu2s)1/2. The calculations were carried out with a diffusion coefficient DLL = DnLn with n = 3. The diffusion coefficient which best fit the observed variations in Jupiter's synchrotron radiation D3 = 1.3 +/- 0.2 x 10-9/s is approximately 0.041/yr, which corresponds to a lagtime of approximately 2 years. We further show that the observed short term (days-weeks) variations in Jupiter's radio emission cannot be explained adequately when radial diffusion is taken into account.

  19. Warm Jupiters Are Less Lonely than Hot Jupiters: Close Neighbors

    NASA Astrophysics Data System (ADS)

    Huang, Chelsea; Wu, Yanqin; Triaud, Amaury H. M. J.

    2016-07-01

    Exploiting the Kepler transit data, we uncover a dramatic distinction in the prevalence of sub-Jovian companions between systems that contain hot Jupiters (HJs) (periods inward of 10 days) and those that host warm Jupiters (WJs) (periods between 10 and 200 days). HJs, with the singular exception of WASP-47b, do not have any detectable inner or outer planetary companions (with periods inward of 50 days and sizes down to 2 R Earth). Restricting ourselves to inner companions, our limits reach down to 1 R Earth. In stark contrast, half of the WJs are closely flanked by small companions. Statistically, the companion fractions for hot and WJs are mutually exclusive, particularly in regard to inner companions. The high companion fraction of WJs also yields clues to their formation. The WJs that have close-by siblings should have low orbital eccentricities and low mutual inclinations. The orbital configurations of these systems are reminiscent of those of the low-mass close-in planetary systems abundantly discovered by the Kepler mission. This, and other arguments, lead us to propose that these WJs are formed in situ. There are indications that there may be a second population of WJs with different characteristics. In this picture, WASP-47b could be regarded as the extending tail of the in situ WJs into the HJ region and does not represent the generic formation route for HJs.

  20. Interplanetary mission design handbook. Volume 1, part 3: Earth to Jupiter ballistic mission opportunities, 1985-2005

    NASA Technical Reports Server (NTRS)

    Sergeyevsky, A. B.; Snyder, G. C.

    1982-01-01

    Graphical data necessary for the preliminary design of ballistic missions to Jupiter are provided. Contours of launch energy requirements, as well as many other launch and Jupiter arrival parameters, are presented in launch date/arrival date space for all launch opportunities from 1985 through 2005. In addition, an extensive text is included which explains mission design methods, from launch window development to Jupiter probe and orbiter arrival design, utilizing the graphical data in this volume as well as numerous equations relating various parameters.

  1. Jupiter's Temperatures--Broad Latitude

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is one of the highest resolution images ever recorded of Jupiter's temperature field. It was obtained by NASA's Galileo mission, with its Photopolarimeter-Radiometer (PPR) experiment, during the seventh of its 10 orbits around Jupiter to date. This map, shown in the left panel, indicates the forces powering Jovian winds, and differentiates between areas of strongest upwelling and downwelling winds in the upper part of the atmosphere. A Hubble Space Telescope Planetary Camera color composite of this same region, taken within 10 hours of the PPR map, is shown in the right panel for the same region, as a reference to the visual clouds. An outline of the region mapped by the PPR is also shown.

    This atmospheric observation covered a broad latitude region, and it shows that the visually dark regions generally have warmer temperatures than the visually light ones, indicating that they are regions of downwelling, dry air which clear out cloud condensate particles. The 'little red spot' at the northernmost part of this image is colder than its surroundings, consistent with it being a region of upwelling and cooling gas. The smaller spots to its southeast (lower right) and other lighter spots in the HST image are all colder than their surroundings, consistent with regions of upwelling and cooling gas. The northern half of the brightest band in the map is brighter than the southern half, and it reveals some detailed structure, down to the 1900- kilometer (1200-mile) resolution of the PPR, which is not always readily correlated with variations of the visual cloud field.

    One surprise of this temperature map involved temperatures near the dark blue-gray feature in the map, an area like the one into which the Probe descended. While large regions of downwelling wind heat the local area elsewhere in Jupiter, this region of vigorous downwelling appears close to being thermally neutral. The drying, downwelling winds may be deeper in the atmosphere than sensed by the PPR

  2. The inner satellites of Jupiter

    NASA Technical Reports Server (NTRS)

    Veverka, J.; Thomas, P.; Synott, S.

    1981-01-01

    The Jupiter moon Amalthea and the smaller satellites J1, J2, and J3, discovered by Voyagers 1 and 2, are discussed under the collective appellation of 'inner satellites', which distinguishes them from the Galilean satellites and the outer satellites, J6-J13. Amalthea is a dark, irregular body on which two large craters are visible, with an estimated surface gravity of 5-7 cm/sec-squared. It is speculated that Amalthea's unique color/reflectance characteristics are due to prolonged charged particle and high-velocity micrometeoroid exposure. Dimensional data are presented for J1-3.

  3. Jupiter's Temperatures--Broad Latitude

    NASA Technical Reports Server (NTRS)

    1997-01-01

    This is one of the highest resolution images ever recorded of Jupiter's temperature field. It was obtained by NASA's Galileo mission, with its Photopolarimeter-Radiometer (PPR) experiment, during the seventh of its 10 orbits around Jupiter to date. This map, shown in the left panel, indicates the forces powering Jovian winds, and differentiates between areas of strongest upwelling and downwelling winds in the upper part of the atmosphere. A Hubble Space Telescope Planetary Camera color composite of this same region, taken within 10 hours of the PPR map, is shown in the right panel for the same region, as a reference to the visual clouds. An outline of the region mapped by the PPR is also shown.

    This atmospheric observation covered a broad latitude region, and it shows that the visually dark regions generally have warmer temperatures than the visually light ones, indicating that they are regions of downwelling, dry air which clear out cloud condensate particles. The 'little red spot' at the northernmost part of this image is colder than its surroundings, consistent with it being a region of upwelling and cooling gas. The smaller spots to its southeast (lower right) and other lighter spots in the HST image are all colder than their surroundings, consistent with regions of upwelling and cooling gas. The northern half of the brightest band in the map is brighter than the southern half, and it reveals some detailed structure, down to the 1900- kilometer (1200-mile) resolution of the PPR, which is not always readily correlated with variations of the visual cloud field.

    One surprise of this temperature map involved temperatures near the dark blue-gray feature in the map, an area like the one into which the Probe descended. While large regions of downwelling wind heat the local area elsewhere in Jupiter, this region of vigorous downwelling appears close to being thermally neutral. The drying, downwelling winds may be deeper in the atmosphere than sensed by the PPR

  4. Models of Jupiter's Growth Incorporating Thermal and Hydrodynamics Constraints

    NASA Astrophysics Data System (ADS)

    D'Angelo, G.; Lissauer, J. J.; Hubickyj, O.; Bodenheimer, P.

    2008-12-01

    We have modeled the growth of Jupiter incorporating both thermal and hydrodynamical constraints on its accretion of gas from the circumsolar disk. We have used a planetary formation code, based on a Henyey- type stellar evolution code, to compute the planet's internal structure and a three-dimensional hydrodynamics code to calculate the planet's interactions with the protoplanetary disk. Our principal results are: (1) Three dimensional hydrodynamics calculations show that the flow of gas in the circumsolar disk limits the region occupied by the planet's tenuous gaseous envelope to within about 0.25 Rh (Hill sphere radii) of the planet's center, which is much smaller than the value of ~ 1 Rh that was assumed in previous studies. (2) This smaller size of the planet's envelope increases the planet's accretion time, but only by 5-- 10%. In general, in agreement with previous results of Hubickyj et al. [Hubickyj, O., Bodenheimer, P., Lissauer, J.J., 2005. Icarus, 179, 415-431], Jupiter formation times are in the range 2.5--3 Myr, assuming a protoplanetary disk with solid surface density of 10 g/cm2 and dust opacity in the protoplanet's envelope equal to 2% that of interstellar material. Thermal pressure limits the rate at which a planet less than a few dozen times as massive as Earth can accumulate gas from the protoplanetary disk, whereas hydrodynamics regulates the growth rate for more massive planets. (3) In a protoplanetary disk whose alpha-viscosity parameter is ~ 0.004, giant planets will grow to several times the mass of Jupiter unless the disk has a small local surface density when the planet begins to accrete gas hydrodynamically, or the disk is dispersed very soon thereafter. The large number of planets known with masses near Jupiter's compared with the smaller number of substantially more massive planets is more naturally explained by planetary growth within circumstellar disks whose alpha-viscosity parameter is ~ 0.0004. (4) Capture of Jupiter's irregular

  5. Galileo In-Situ Dust Measurements in Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Krueger, H.; Hamilton, D. P.; Gruen, E.

    Thebe's and Amalthea's orbit. This structure as well as the Thebe ring extension may be explained by variable photoelectric grain charging on the day- and night-sides of Jupiter and the resulting variable susceptibility of the grains to electromagnetic forces. The Galileo measurements in Jupiter's gossamer ring pave the way towards the in-situ investigation of Saturn's E ring with Cassini beginning in July 2004.

  6. The current sheet in Jupiter's magnetosphere

    NASA Technical Reports Server (NTRS)

    Goertz, C. K.

    1975-01-01

    A theoretical model is presented for the plasma in the Jovian magnetosphere whose pressure is comparable to the corotational energy density. The model predicts a thin current sheet of 1 Jupiter radius to 2 Jupiter radii half-thickness. The current sheet lies almost precisely in the magnetic equatorial plane and is not appreciably warped as suggested previously.

  7. Encounter with Jupiter. [Pioneer 10 space probe

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Pioneer 10 space probe's encounter with the Jupiter is discussed in detail. Tables are presented which include data on the distances during the encounter, times of crossing satellite orbits, important events in the flight near Jupiter, and time of experiments. Educational study projects are also included.

  8. Dynamical timescales in the Jupiter family

    NASA Technical Reports Server (NTRS)

    Lindgren, Mats

    1992-01-01

    Numerically integrated fictitious comets starting in orbits perihelion tangent to Jupiter have been used to estimate the duration of a typical visit to the observable Jupiter family of comets. The results show values of 3 to 6 thousand years, narrowing the previously estimated interval of 10(exp 3) to 10(exp 4) years.

  9. Hot Jupiters from secular planet-planet interactions.

    PubMed

    Naoz, Smadar; Farr, Will M; Lithwick, Yoram; Rasio, Frederic A; Teyssandier, Jean

    2011-05-12

    About 25 per cent of 'hot Jupiters' (extrasolar Jovian-mass planets with close-in orbits) are actually orbiting counter to the spin direction of the star. Perturbations from a distant binary star companion can produce high inclinations, but cannot explain orbits that are retrograde with respect to the total angular momentum of the system. Such orbits in a stellar context can be produced through secular (that is, long term) perturbations in hierarchical triple-star systems. Here we report a similar analysis of planetary bodies, including both octupole-order effects and tidal friction, and find that we can produce hot Jupiters in orbits that are retrograde with respect to the total angular momentum. With distant stellar mass perturbers, such an outcome is not possible. With planetary perturbers, the inner orbit's angular momentum component parallel to the total angular momentum need not be constant. In fact, as we show here, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter.

  10. Jupiter's decisive role in the inner Solar System's early evolution.

    PubMed

    Batygin, Konstantin; Laughlin, Greg

    2015-04-07

    The statistics of extrasolar planetary systems indicate that the default mode of planet formation generates planets with orbital periods shorter than 100 days and masses substantially exceeding that of the Earth. When viewed in this context, the Solar System is unusual. Here, we present simulations which show that a popular formation scenario for Jupiter and Saturn, in which Jupiter migrates inward from a > 5 astronomical units (AU) to a ≈ 1.5 AU before reversing direction, can explain the low overall mass of the Solar System's terrestrial planets, as well as the absence of planets with a < 0.4 AU. Jupiter's inward migration entrained s ≳ 10-100 km planetesimals into low-order mean motion resonances, shepherding and exciting their orbits. The resulting collisional cascade generated a planetesimal disk that, evolving under gas drag, would have driven any preexisting short-period planets into the Sun. In this scenario, the Solar System's terrestrial planets formed from gas-starved mass-depleted debris that remained after the primary period of dynamical evolution.

  11. Tour of Jupiter Galilean moons: Winning solution of GTOC6

    NASA Astrophysics Data System (ADS)

    Colasurdo, Guido; Zavoli, Alessandro; Longo, Alessandro; Casalino, Lorenzo; Simeoni, Francesco

    2014-09-01

    The paper presents the trajectory designed by the Italian joint team Politecnico di Torino & Sapienza Università di Roma (Team5), winner of the 6th edition of the Global Trajectory Optimization Competition (GTOC6). In the short time available in these competitions, Team5 resorted to basic knowledge, simple tools and a powerful indirect optimization procedure. The mission concerns a 4-year tour of the Jupiter Galilean moons. The paper explains the strategy that was preliminarily devised and eventually implemented by looking for a viable trajectory. The first phase is a capture that moves the spacecraft from the arrival hyperbola to a low-energy orbit around Jupiter. Six series of flybys follow; in each one the spacecraft orbits Jupiter in resonance with a single moon; criteria to construct efficient chains of resonant flybys are presented. Transfer legs move the spacecraft from resonance with a moon to another one; precise phasing of the relevant moons is required; mission opportunities in a 11-year launch window are found by assuming ballistic trajectories and coplanar circular orbits for the Jovian satellites. The actual trajectory is found by using an indirect technique.

  12. Voyager 1 Jupiter Southern Hemisphere Movie

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This movie shows a portion of Jupiter in the southern hemisphere over 17Jupiter days. Above the white belt, notice the series of atmospheric vortices headed west. Even these early approach frames show wild dynamics in the roiling environment south of the white belt. Notice the small tumbling white cloud near the center.

    As Voyager 1 approached Jupiter in 1979, it took images of the planet at regular intervals. This sequence is made from 17 images taken once every Jupiter rotation period (about 10 hours). These images were acquired in the Blue filter around Feb. 1, 1979. The spacecraft was about 37 million kilometers from Jupiter at that time.

    This time-lapse movie was produced at JPL by the Image Processing Laboratory in 1979.

  13. THE PHOTOECCENTRIC EFFECT AND PROTO-HOT JUPITERS. III. A PAUCITY OF PROTO-HOT JUPITERS ON SUPER-ECCENTRIC ORBITS

    SciTech Connect

    Dawson, Rebekah I.; Murray-Clay, Ruth A.; Johnson, John Asher

    2015-01-10

    Gas giant planets orbiting within 0.1 AU of their host stars are unlikely to have formed in situ and are evidence for planetary migration. It is debated whether the typical hot Jupiter smoothly migrated inward from its formation location through the proto-planetary disk, or was perturbed by another body onto a highly eccentric orbit, which tidal dissipation subsequently shrank and circularized during close stellar passages. Socrates and collaborators predicted that the latter model should produce a population of super-eccentric proto-hot Jupiters readily observable by Kepler. We find a paucity of such planets in the Kepler sample, which is inconsistent with the theoretical prediction with 96.9% confidence. Observational effects are unlikely to explain this discrepancy. We find that the fraction of hot Jupiters with an orbital period P > 3 days produced by the star-planet Kozai mechanism does not exceed (at two-sigma) 44%. Our results may indicate that disk migration is the dominant channel for producing hot Jupiters with P > 3 days. Alternatively, the typical hot Jupiter may have been perturbed to a high eccentricity by interactions with a planetary rather than stellar companion, and began tidal circularization much interior to 1 AU after multiple scatterings. A final alternative is that early in the tidal circularization process at high eccentricities tidal circularization occurs much more rapidly than later in the process at low eccentricities, although this is contrary to current tidal theories.

  14. The Photoeccentric Effect and Proto-hot Jupiters. III. A Paucity of Proto-hot Jupiters on Super-eccentric Orbits

    NASA Astrophysics Data System (ADS)

    Dawson, Rebekah I.; Murray-Clay, Ruth A.; Johnson, John Asher

    2015-01-01

    Gas giant planets orbiting within 0.1 AU of their host stars are unlikely to have formed in situ and are evidence for planetary migration. It is debated whether the typical hot Jupiter smoothly migrated inward from its formation location through the proto-planetary disk, or was perturbed by another body onto a highly eccentric orbit, which tidal dissipation subsequently shrank and circularized during close stellar passages. Socrates and collaborators predicted that the latter model should produce a population of super-eccentric proto-hot Jupiters readily observable by Kepler. We find a paucity of such planets in the Kepler sample, which is inconsistent with the theoretical prediction with 96.9% confidence. Observational effects are unlikely to explain this discrepancy. We find that the fraction of hot Jupiters with an orbital period P > 3 days produced by the star-planet Kozai mechanism does not exceed (at two-sigma) 44%. Our results may indicate that disk migration is the dominant channel for producing hot Jupiters with P > 3 days. Alternatively, the typical hot Jupiter may have been perturbed to a high eccentricity by interactions with a planetary rather than stellar companion, and began tidal circularization much interior to 1 AU after multiple scatterings. A final alternative is that early in the tidal circularization process at high eccentricities tidal circularization occurs much more rapidly than later in the process at low eccentricities, although this is contrary to current tidal theories.

  15. Hot-Jupiter Breakfasts Realign Stars

    NASA Astrophysics Data System (ADS)

    Kohler, Susanna

    2015-08-01

    Two researchers at the University of Chicago have recently developed a new theory to explain an apparent dichotomy in the orbits of planets around cool vs. hot stars. Their model proposes that the spins of cool stars are affected when they ingest hot Jupiters (HJs) early in their stellar lifetimes. A Puzzling Dichotomy: In exoplanet studies, there is a puzzling difference observed between planet orbits around cool and hot (those with Teff ≥ 6250 K) stars: the orbital planes of planets around cool stars are primarily aligned with the host star's spin, whereas the orbital planes of planets around hot stars seem to be randomly distributed. Previous attempts to explain this dichotomy have focused on tidal interactions between the host star and the planets observed in the system. Now Titos Matsakos and Arieh Königl have taken these models a step further — by including in their calculations not only the effects of observed planets, but also those of HJs that may have been swallowed by the star long before we observed the systems. Modeling Meals: Plots of the distribution of the obliquity λ for hot Jupiters around cool hosts (upper plot) and hot hosts (lower plot). The dashed line shows the initial distribution, the bins show the model prediction for the final distribution after the systems evolve, and the black dots show the current observational data. [Matsakos & Königl, 2015]" class="size-thumbnail wp-image-223" height="386" src="http://aasnova.org/wp-content/uploads/2015/08/fig22-260x386.png" width="260" /> Plots of the distribution of the obliquity λ for hot Jupiters around cool hosts (upper plot) and hot hosts (lower plot). The dashed line shows the initial distribution, the bins show the model prediction for the final distribution after the systems evolve, and the black dots show the current observational data. [Matsakos & Königl, 2015] The authors' model assumes that as HJs are formed and migrate inward through the protoplanetary disk, they stall out near

  16. Longitudinal Variations in Jupiter's Winds

    NASA Technical Reports Server (NTRS)

    Simon-Miller, Amy A.; Gierasch, P. J.; Tierney, G.

    2010-01-01

    Long-term studies of Jupiter's zonal wind field revealed temporal variations on the order of 20 to 40 m/s at many latitudes, greater than the typical data uncertainties of 1 to 10 m/s. No definitive periodicities were evident, however, though some latitudinally-confined signals did appear at periods relevant to the Quasi- Quadrennial Oscillation (Simon-Miller & Gierasch, Icarus, in press). As the QQO appears, from vertical temperature profiles, to propagate downward, it is unclear why a signal is not more obvious, unless other processes dominate over possibly weaker forcing from the QQO. An additional complication is that zonal wind profiles represent an average over some particular set of longitudes for an image pair and most data sets do not offer global wind coverage. Lien avoiding known features, such as the large anticyclonic vortices especially prevalent in the south, there can be distinct variations in longitude. We present results on the full wind field from Voyager and Cassini data, showing apparent longitudinal variations of up to 60 m/s or more. These are particularly obvious near disruptions such as the South Equatorial Disturbance, even when the feature itself is not clearly visible. These two dates represent very different states of the planet for comparison: Voyagers 1 & 2 flew by Jupiter shortly after a global upheaval, while many regions were in a disturbed state, while the Cassini view is typical of a more quiescent period present during much of the 1990s and early 2000s.

  17. Jupiter's magnetosphere and radiation belts

    NASA Technical Reports Server (NTRS)

    Kennel, C. F.; Coroniti, F. V.

    1979-01-01

    Radioastronomy and Pioneer data reveal the Jovian magnetosphere as a rotating magnetized source of relativistic particles and radio emission, comparable to astrophysical cosmic ray and radio sources, such as pulsars. According to Pioneer data, the magnetic field in the outer magnetosphere is radially extended into a highly time variable disk-shaped configuration which differs fundamentally from the earth's magnetosphere. The outer disk region, and the energetic particles confined in it, are modulated by Jupiter's 10 hr rotation period. The entire outer magnetosphere appears to change drastically on time scales of a few days to a week. In addition to its known modulation of the Jovian decametric radio bursts, Io was found to absorb some radiation belt particles and to accelerate others, and most importantly, to be a source of neutral atoms, and by inference, a heavy ion plasma which may significantly affect the hydrodynamic flow in the magnetosphere. Another important Pioneer finding is that the Jovian outer magnetosphere generates, or permits to escape, fluxes of relativistic electrons of such intensities that Jupiter may be regarded as the dominant source of 1 to 30 MeV cosmic ray electrons in the heliosphere.

  18. Engineering a Solution to Jupiter Exploration

    NASA Technical Reports Server (NTRS)

    Clark, Karla; Magner, Thomas; Lisano, Michael; Pappalardo, Robert

    2010-01-01

    The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) explore Europa to investigate its habitability, (2) characterize Ganymede as a planetary object including its potential habitability and (3) explore the Jupiter system as an archetype for gas giants. NASA and ESA have concluded a detailed joint study of a mission to Europa, Ganymede, and the Jupiter system with conceptual orbiters developed by NASA and ESA. The baseline EJSM architecture consists of two primary elements operating simultaneously in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. EJSM would directly address themes concerning the origin and evolution of satellite systems and water-rich environments in icy satellites. The potential habitability of the ocean-bearing moons Europa and Ganymede would be investigated, by characterizing the geophysical, compositional, geological, and external processes that affect these icy worlds. EJSM would also investigate Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant planets and their satellites would be better known. Most importantly, EJSM would shed new light on the potential for the emergence of life in the celestial neighborhood and beyond. The EJSM baseline architecture would provide opportunities for coordinated synergistic observations by JEO and JGO of the Jupiter and Ganymede magnetospheres, the volcanoes and torus of Io, the atmosphere of Jupiter, and comparative planetology of icy satellites. Each spacecraft would conduct both synergistic dual-spacecraft investigations and stand

  19. Engineering a Solution to Jupiter Exploration

    NASA Technical Reports Server (NTRS)

    Clark, Karla; Magner, Thomas; Lisano, Michael; Pappalardo, Robert

    2010-01-01

    The Europa Jupiter System Mission (EJSM) would be an international mission with the overall theme of investigating the emergence of habitable worlds around gas giants. Its goals are to (1) explore Europa to investigate its habitability, (2) characterize Ganymede as a planetary object including its potential habitability and (3) explore the Jupiter system as an archetype for gas giants. NASA and ESA have concluded a detailed joint study of a mission to Europa, Ganymede, and the Jupiter system with conceptual orbiters developed by NASA and ESA. The baseline EJSM architecture consists of two primary elements operating simultaneously in the Jovian system: the NASA-led Jupiter Europa Orbiter (JEO), and the ESA-led Jupiter Ganymede Orbiter (JGO). JEO and JGO would execute an intricately choreographed exploration of the Jupiter System before settling into orbit around Europa and Ganymede, respectively. EJSM would directly address themes concerning the origin and evolution of satellite systems and water-rich environments in icy satellites. The potential habitability of the ocean-bearing moons Europa and Ganymede would be investigated, by characterizing the geophysical, compositional, geological, and external processes that affect these icy worlds. EJSM would also investigate Io and Callisto, Jupiter's atmosphere, and the Jovian magnetosphere. By understanding the Jupiter system and unraveling its history, the formation and evolution of gas giant planets and their satellites would be better known. Most importantly, EJSM would shed new light on the potential for the emergence of life in the celestial neighborhood and beyond. The EJSM baseline architecture would provide opportunities for coordinated synergistic observations by JEO and JGO of the Jupiter and Ganymede magnetospheres, the volcanoes and torus of Io, the atmosphere of Jupiter, and comparative planetology of icy satellites. Each spacecraft would conduct both synergistic dual-spacecraft investigations and stand

  20. ATMOSPHERIC CIRCULATION OF HOT JUPITERS: DAYSIDE–NIGHTSIDE TEMPERATURE DIFFERENCES

    SciTech Connect

    Komacek, Thaddeus D.; Showman, Adam P.

    2016-04-10

    The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing dayside-to-nightside brightness temperature difference with increasing equilibrium temperature. Here, we present a three-dimensional model that explains this relationship, in order to provide insight into the processes that control heat redistribution in tidally locked planetary atmospheres. This three-dimensional model combines predictive analytic theory for the atmospheric circulation and dayside–nightside temperature differences over a range of equilibrium temperatures, atmospheric compositions, and potential frictional drag strengths with numerical solutions of the circulation that verify this analytic theory. The theory shows that the longitudinal propagation of waves mediates dayside–nightside temperature differences in hot Jupiter atmospheres, analogous to the wave adjustment mechanism that regulates the thermal structure in Earth’s tropics. These waves can be damped in hot Jupiter atmospheres by either radiative cooling or potential frictional drag. This frictional drag would likely be caused by Lorentz forces in a partially ionized atmosphere threaded by a background magnetic field, and would increase in strength with increasing temperature. Additionally, the amplitude of radiative heating and cooling increases with increasing temperature, and hence both radiative heating/cooling and frictional drag damp waves more efficiently with increasing equilibrium temperature. Radiative heating and cooling play the largest role in controlling dayside–nightside temperature differences in both our analytic theory and numerical simulations, with frictional drag only being important if it is stronger than the Coriolis force. As a result, dayside–nightside temperature differences in hot Jupiter atmospheres increase with increasing stellar irradiation and decrease with increasing pressure.

  1. Atmospheric Circulation of Hot Jupiters: Dayside-Nightside Temperature Differences

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Showman, Adam P.

    2016-04-01

    The full-phase infrared light curves of low-eccentricity hot Jupiters show a trend of increasing dayside-to-nightside brightness temperature difference with increasing equilibrium temperature. Here, we present a three-dimensional model that explains this relationship, in order to provide insight into the processes that control heat redistribution in tidally locked planetary atmospheres. This three-dimensional model combines predictive analytic theory for the atmospheric circulation and dayside-nightside temperature differences over a range of equilibrium temperatures, atmospheric compositions, and potential frictional drag strengths with numerical solutions of the circulation that verify this analytic theory. The theory shows that the longitudinal propagation of waves mediates dayside-nightside temperature differences in hot Jupiter atmospheres, analogous to the wave adjustment mechanism that regulates the thermal structure in Earth’s tropics. These waves can be damped in hot Jupiter atmospheres by either radiative cooling or potential frictional drag. This frictional drag would likely be caused by Lorentz forces in a partially ionized atmosphere threaded by a background magnetic field, and would increase in strength with increasing temperature. Additionally, the amplitude of radiative heating and cooling increases with increasing temperature, and hence both radiative heating/cooling and frictional drag damp waves more efficiently with increasing equilibrium temperature. Radiative heating and cooling play the largest role in controlling dayside-nightside temperature differences in both our analytic theory and numerical simulations, with frictional drag only being important if it is stronger than the Coriolis force. As a result, dayside-nightside temperature differences in hot Jupiter atmospheres increase with increasing stellar irradiation and decrease with increasing pressure.

  2. THE HIGH ALBEDO OF THE HOT JUPITER KEPLER-7 b

    SciTech Connect

    Demory, Brice-Olivier; Seager, Sara; Madhusudhan, Nikku; Kjeldsen, Hans; Christensen-Dalsgaard, Joergen; Gillon, Michael; Rowe, Jason F.; Borucki, William J.; Koch, David G.; Welsh, William F.; Adams, Elisabeth R.; Dupree, Andrea; McCarthy, Don; Kulesa, Craig

    2011-07-01

    Hot Jupiters are expected to be dark from both observations (albedo upper limits) and theory (alkali metals and/or TiO and VO absorption). However, only a handful of hot Jupiters have been observed with high enough photometric precision at visible wavelengths to investigate these expectations. The NASA Kepler mission provides a means to widen the sample and to assess the extent to which hot Jupiter albedos are low. We present a global analysis of Kepler-7 b based on Q0-Q4 data, published radial velocities, and asteroseismology constraints. We measure an occultation depth in the Kepler bandpass of 44 {+-} 5 ppm. If directly related to the albedo, this translates to a Kepler geometric albedo of 0.32 {+-} 0.03, the most precise value measured so far for an exoplanet. We also characterize the planetary orbital phase light curve with an amplitude of 42 {+-} 4 ppm. Using atmospheric models, we find it unlikely that the high albedo is due to a dominant thermal component and propose two solutions to explain the observed planetary flux. First, we interpret the Kepler-7 b albedo as resulting from an excess reflection over what can be explained solely by Rayleigh scattering, along with a nominal thermal component. This excess reflection might indicate the presence of a cloud or haze layer in the atmosphere, motivating new modeling and observational efforts. Alternatively, the albedo can be explained by Rayleigh scattering alone if Na and K are depleted in the atmosphere by a factor of 10-100 below solar abundances.

  3. Lacking "Lack": A Reply to Joldersma

    ERIC Educational Resources Information Center

    Marshall, James D.

    2007-01-01

    First I would like to thank Clarence Joldersma for his review of our "Poststructuralism, Philosophy, Pedagogy" (Marshall, 2004-PPP). In particular, I would thank him for his opening sentence: "[t]his book is a response to a lack." It is the notion of a lack, noted again later in his review, which I wish to take up mainly in this response. Rather…

  4. Ultraviolet observations of Jupiter and Uranus

    SciTech Connect

    Wagener, R.

    1986-01-01

    To further understand the processes that led to the formation of organic molecules in the atmosphere of the primitive Earth, two of the planets that have maintained their reducing atmospheres were studied. The Observations consist of spectra obtained with the International Ultraviolet Explorer (IUE) in the wavelength region from 1400 to 3350 A. After examining IUE spectra of Saturn's Rings, Mars, and the solar analogs 16 Cyg A and B, rocket measurements of the full disk solar spectrum (Mount and Rottman, 1981; 1983s) were found to be the preferable solar calibration for calibration for calculating planetary reflectivities. A vertically inhomogeneous radiative transfer program was used to compute reflectivities of various model stratospheric compositions for comparison with the planetary spectra. The analysis of the equatorial region of Jupiter resulted in the detection of allene (C/sub 3/H/sub 4/) and another absorber near 1600 A, possibly cyclopropane (C/sub 3/H/sub 6/) or a high altitude haze. Small aperture observations of the Great Red Spot (GRS) and the South Tropical Zone (STrZ) in the 1900 to 2200 A wavelength region show that the enhancement of vertical mixing in the GRS due to upwelling is small and is not capable of significantly enhancing the PH/sub 3/ abundance in the GRS. Thus, the photolysis of PH/sub 3/ cannot be invoked to explain the red coloration of the GRS. Alternatives, such as nitrogen bearing compounds, should continue to be considered.

  5. Energetic neutral particles from Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Cheng, A. F.

    1986-01-01

    The Voyager 1 spacecraft has detected energetic neutral particles escaping from the magnetospheres of Jupiter and Saturn. These energetic neutrals are created in charge exchange reactions between radiation belt ions and ambient atoms or molecules in the magnetosphere. If the Io torus is assumed to be the dominant Jovian source region for energetic neutrals, the Voyager observations can be used to infer upper limits to the average ion intensities there below about 200 keV. No readily interpretable in-situ measurements are available in the Io torus at these energies. The middle and outer Jovian magnetospheres may also be a significant source of energetic neutrals. At Saturn, the observed neutral particle count rates are too high to be explained by charge exchange between fast protons and H atoms of the Titan torus. Most of the energetic neutrals may be produced by charge exchanges between heavy ions and a neutral cloud containing H2O in Saturn's inner magnetosphere. If so, the Voyager measurements of energetic neutral fluxes would be the first detected emissions from this region of Saturn's magnetosphere.

  6. Dynamics of dust in Jupiter's gossamer rings

    NASA Astrophysics Data System (ADS)

    Hamilton, D.; Burns, J.; Krueger, H.; Showalter, M.

    2003-04-01

    Over the past several years, the Galileo spacecraft has drastically improved our knowledge of Jupiter's faint rings. We now know the system to be composed of a main ring 7000km wide whose inner edge blossoms into a vertically-extended halo, and a pair of gossamer rings, each one extending inward from a small moon. These moonlets, Thebe and Amalthea, have large orbital tilts and resulting vertical excursions of 1150km and 4300km, respectively. The vertical thicknesses of the two Gossamer rings accurately match these values, providing compelling evidence that the two small satellites act as the dominant sources of ring material. Ring Material is born during high speed impacts onto the moonlet surfaces, after which the material evolves inward under the action of a dissipative force, either Poynting-Robertson Drag or Resonant Charge Variations. The basic framework for the origin and evolution of the Gossamer Rings is well understood, but there are a few loose ends that are not so easily explained: i) an outward extension of the Thebe Ring, ii) the nature of the dissipative force. In this talk I will report my latest dynamical modeling of the Gossamer rings associated with Thebe and Amalthea, and will discuss how in-situ impact data collected by the Galileo dust detector during the first ever ring "fly-through" may help to resolve some of these and other outstanding issues.

  7. Analysis of chorus emissions at Jupiter

    NASA Astrophysics Data System (ADS)

    Coroniti, F. V.; Scarf, F. L.; Kennel, C. F.; Kurth, W. S.

    1984-06-01

    The emissions in the chorus frequency band which were detected on the Voyager 1 inbound pass between about ten and six Jupiter radii are surveyed. An overview of the plasma and wave observations during the inbound pass is presented and the spatial regions in which chorus band signals were observed are discussed. A series of wide-band frequency-time frames which characterize the onset of two observed intervals of chorus band activity is displayed. A detailed examination is made of the spectra for rising chorus which sweeps upward in frequency from 0.2 to 0.5 times the electron cyclotron frequency f(c). Two temporally successive wide-band frames in which several types of chorus band emissions were observed are discussed. The spatial morphology of chorus is discussed in terms of the electron energies which resonate with whistler mode waves. A recent theory of chorus generation is reviewed along with theories and a model explaining the narrow-band emissions above f(c)/2.

  8. A study of the time variability of Jupiter's atmospheric structure

    NASA Astrophysics Data System (ADS)

    Kuehn, D. M.; Beebe, R. F.

    1993-02-01

    Aspects of the time-variable nature of the Jovian atmosphere are addressed using high-resolution photometrically calibrated multicolored imaging data obtained over two Jovian apparitions. During the period of observations, Jupiter's South Equatorial Belts (SEB) underwent a drastic brightening and its Equatorial Zone gradually darkened throughout the period. Based on the data, vertically inhomogeneous atmospheric structure models are constructed and used to make direct quantitative comparisons between different latitudinal regions and different epochs. The drastic brightening of the SEB is explained by an increase in both the optical thickness and the single-scattering albedo of the upper tropospheric cloud.

  9. Modeling Jupiter's decametric modulation lanes

    NASA Astrophysics Data System (ADS)

    Imai, Kazumasa; Wang, Liyun; Carr, Thomas D.

    1997-04-01

    The modulation lanes in Jupiter's decametric radio spectra were discovered by Riihimaa [1968]. We have developed a model for the mechanism responsible for their production in which the free parameters have been adjusted to provide a very close fit with the observations. In our model, a grid-like interference screen composed of field-aligned columns of enhanced or depleted plasma density is located near Io's orbit close to the longitude of the sub-Earth point. The column spacing is typically about 140 km. As a band of frequency components emitted from near the foot of an excited tube of magnetic flux passes through the screen, interference patterns of slightly different orientations are produced by the different frequencies. The corotation of this set of interference patterns with Jupiter results in the sloping modulation lanes of the observed dynamic spectrum. Newly calculated results indicate that (1) the Io-B and Io-A radiations are emitted from the northern hemisphere, while that from Io-C comes mainly from the southern hemisphere, (2) the half-angle of the assumed hollow-cone emission beam for Io-B is typically 60°, with a variation of a few degrees, and (3) the equatorial lead angle of the radio-emitting previously excited flux tube ahead of the flux tube through Io at the same instant is more variable, 50° being a typical value for Io-B. Modulation lanes from Io-unrelated emission were also successfully modeled, the assumption in this case being that some source of energy other than a direct encounter with Io excited the flux tube containing the emitting radio source. The L shell value for non-Io-A was less clearly defined but was definitely between 4 and 7. Sensitive measurements of the lane modulation depths for Io-B and Io-A indicated that the decay time for the columns of the interference screen is of the same order of magnitude as Jupiter's rotation period. Although the predominant modulation lane periodicity of about 2 s indicates an upper limit on Io

  10. Jupiter Thermospheric General Circulation Model (jtgcm)

    NASA Astrophysics Data System (ADS)

    Majeed, T.; Waite, J. H.; Bougher, S. W.; Gladstone, G. R.

    Recent observations of infrared and FUV auroral emissions from Jupiter have shown the presence of high-speed (> 2km/s) winds in the jovian thermosphere. The Galileo probe measurements of the altitude profile of equatorial temperature exhibit wave-like oscillations at all altitudes from 1029 to 133 km above the 1-bar level. A number of recent studies interpret these oscillations as being due to upward propagating gravity waves. The transport of significant auroral energy and species to equatorial latitudes by the thermospheric winds has also been proposed to explain the measured temper- ature structure observed by the Galileo probe. We examine this hypothesis using a fully 3-D Jupiter Thermospheric General Circulation Model (JTGCM) that has been developed and exercised to address global scale temperature, wind, and neutral-ion specie distributions. It was developed from a suitable adaptation of the NCAR Ther- mosphere Ionosphere General Circulation Model (TIGCM). New code was developed to parameterize the estimated auroral and equatorial heating and ionization distribu- tions learned from Galileo, HST, ROSAT, and Voyager data. Asymmetric auroral ovals are specified separately for the north and south poles. The lower boundary is set at 20 µb in order to capture the bulk of the hydrocarbon cooling due to C2H2 and CH4 at the base of the thermosphere. The upper boundary is set at 10-4 nb, sufficiently high enough to capture most auroral heating processes and winds. An ion-drag scheme is incorporated based on the formulation described by Roble and Ridley [1987]. A con- vection electric field is estimated and corresponding ion drifts are generated using the formulation of Evitar and Barbosa [1984]. These prescriptions provide a means to test the general impact of ion drag and Joule heating on the JTGCM neutral winds. The JTGCM has been fully spun-up (closely approaching steady state) and exercised for various cases to simulate 3-component neutral winds, and corresponding

  11. Atmospheric Heat Redistribution on Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Perez-Becker, D.; Showman, A. P.

    2013-12-01

    Infrared lightcurves of transiting hot Jupiters present a trend in which the atmospheres of the hottest planets are less efficient at redistributing the stellar energy absorbed on their daysides---and thus have a larger day-night temperature contrast---than colder planets. To this day, no predictive atmospheric model has been published that identifies which dynamical mechanisms determine the atmospheric heat redistribution efficiency on tidally locked exoplanets. We present a two-layer shallow water model of the atmospheric dynamics on synchronously rotating planets that explains why heat redistribution efficiency drops as stellar insolation rises. Our model shows that planets with weak friction and weak irradiation exhibit a banded zonal flow with minimal day-night temperature differences, while models with strong irradiation and/or strong friction exhibit a day-night flow pattern with order-unity fractional day-night temperature differences. To interpret the model, we develop a scaling theory that shows that the timescale for gravity waves to propagate horizontally over planetary scales, τwave, plays a dominant role in controlling the transition from small to large temperature contrasts. This implies that heat redistribution is governed by a wave-like process, similar to the one responsible for the weak temperature gradients in the Earth's tropics. When atmospheric drag can be neglected, the transition from small to large day-night temperature contrasts occurs when τwave ~ (τrad/Ω)1/2, where τrad is the radiative relaxation time, and Ω is the planetary rotation frequency. Alternatively, this transition criterion can be expressed in terms of τvert, the timescale for a fluid parcel to move vertically over the difference in day-night thickness. The transition then occurs when τrad ~ τvert. These results subsume the more widely used timescale comparison for estimating heat redistribution efficiency between τrad and the timescale for large-scale horizontal

  12. ATMOSPHERIC HEAT REDISTRIBUTION ON HOT JUPITERS

    SciTech Connect

    Perez-Becker, Daniel; Showman, Adam P.

    2013-10-20

    Infrared light curves of transiting hot Jupiters present a trend in which the atmospheres of the hottest planets are less efficient at redistributing the stellar energy absorbed on their daysides—and thus have a larger day-night temperature contrast—than colder planets. To this day, no predictive atmospheric model has been published that identifies which dynamical mechanisms determine the atmospheric heat redistribution efficiency on tidally locked exoplanets. Here we present a shallow-water model of the atmospheric dynamics on synchronously rotating planets that explains why heat redistribution efficiency drops as stellar insolation rises. Our model shows that planets with weak friction and weak irradiation exhibit a banded zonal flow with minimal day-night temperature differences, while models with strong irradiation and/or strong friction exhibit a day-night flow pattern with order-unity fractional day-night temperature differences. To interpret the model, we develop a scaling theory which shows that the timescale for gravity waves to propagate horizontally over planetary scales, τ{sub wave}, plays a dominant role in controlling the transition from small to large temperature contrasts. This implies that heat redistribution is governed by a wave-like process, similar to the one responsible for the weak temperature gradients in the Earth's tropics. When atmospheric drag can be neglected, the transition from small to large day-night temperature contrasts occurs when τ{sub wave}∼√(τ{sub rad}/Ω), where τ{sub rad} is the radiative relaxation time and Ω is the planetary rotation frequency. Alternatively, this transition criterion can be expressed as τ{sub rad} ∼ τ{sub vert}, where τ{sub vert} is the timescale for a fluid parcel to move vertically over the difference in day-night thickness. These results subsume the more widely used timescale comparison for estimating heat redistribution efficiency between τ{sub rad} and the horizontal day

  13. Visible spectral slope survey of Jupiter Trojans

    NASA Astrophysics Data System (ADS)

    Erasmus, Nicolas; Rivkin, Andrew S.; Sickafoose, Amanda A.

    2016-10-01

    Jupiter's Trojans are predicted by the Nice Model [1,2] to be Trans-Neptunian Objects (TNOs) that moved from 30+ AU to 5.2 AU during the early evolution period of the Solar System. This model, predicting giant planet migration and widespread transport of material throughout the Solar System, is however still lacking important constraints. Correlations between the composition, size, and orbital geometry of Jupiter's Trojans can provide additional information to test predicted migration and evolution models.Two main colour groups have been observed, roughly equivalent to the C (plus low-albedo X) and D classes with distinguishable spectral slopes, and one interpretation is that the two groups have different compositions [3]. Independent compositions together with hints of differing orbital inclination distributions could imply separate formation locations; therefore, determining the relative fractions of C and D asteroids at different sizes would provide a key test for Solar System dynamical models. However, there is a caveat: the distinct colour groups could also arise by other means. Regolith processes or "space weathering" such as micrometeorite impacts and UV irradiation of ice are also plausible explanations for a range of spectrographic slopes from C-like to D-like [4].Here we report on our latest survey observations at Sutherland, South Africa of approximately 50 Trojan targets using the Sutherland High Speed Optical Camera (SHOC) [5] on the 74" telescope. These observations are part of a larger multi-telescope survey to determine the spectral slopes (C-like or D-like) for multiple Trojans, focusing on those of small size. These slopes can be used to determine the relative fraction of C+X and D asteroids at different sizes to determine whether what is seen is more consistent with regolith processes or different compositions.References:[1] A. Morbidelli, et al. Nature, 435, 462-465, (2005)[2] R. Gomes, et al. Nature 435, 466-469 (2005)[3] J.P. Emery, et al. The

  14. The magnetic field of Jupiter

    NASA Technical Reports Server (NTRS)

    Acuna, M. H.; Ness, N. F.

    1976-01-01

    The paper is concerned mainly with the intrinsic planetary field which dominates the inner magnetosphere up to a distance of 10 to 12 Jovian radii where other phenomena, such as ring currents and diamagnetic effects of trapped charged particles, become significant. The main magnetic field of Jupiter as determined by in-situ observations by Pioner 10 and 11 is found to be relatively more complex than a simple offset tilted dipole. Deviations from a simple dipole geometry lead to distortions of the charged particle L shells and warping of the magnetic equator. Enhanced absorption effects associated with Io and Amalthea are predicted. The results are consistent with the conclusions derived from extensive radio observations at decimetric and decametric wavelengths for the planetary field.

  15. Hubble Clicks Images of Io Sweeping Across Jupiter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    While hunting for volcanic plumes on Io, NASA's Hubble Space Telescope captured these images of the volatile moon sweeping across the giant face of Jupiter. Only a few weeks before these dramatic images were taken, the orbiting telescope snapped a portrait of one of Io's volcanoes spewing sulfur dioxide 'snow.'

    These stunning images of the planetary duo are being released to commemorate the ninth anniversary of the Hubble telescope's launch on April 24, 1990. All of these images were taken with the Wide Field and Planetary Camera 2.

    The three overlapping snapshots show in crisp detail Io passing above Jupiter's turbulent clouds. The close-up picture of Io (bottom right) reveal a 120-mile-high (200-kilometer) plume of sulfur dioxide 'snow' emanating from Pillan, one of the moon's active volcanoes.

    'Other observations have inferred sulfur dioxide 'snow' in Io's plumes, but this image offers direct observational evidence for sulfur dioxide 'snow' in an Io plume,' explains John R. Spencer of Lowell Observatory in Flagstaff, Ariz.

    A Trip Around Jupiter

    The three snapshots of the volcanic moon rounding Jupiter were taken over a 1.8-hour time span. Io is roughly the size of Earth's moon but 2,000 times farther away. In two of the images, Io appears to be skimming Jupiter's cloud tops, but it's actually 310,000 miles (500,000 kilometers) away. Io zips around Jupiter in 1.8 days, whereas the moon circles Earth every 28 days.

    The conspicuous black spot on Jupiter is Io's shadow and is about the size of the moon itself (2,262 miles or 3,640 kilometers across). This shadow sails across the face of Jupiter at 38,000 mph (17 kilometers per second). The smallest details visible on Io and Jupiter measure 93 miles (150 kilometers) across, or about the size of Connecticut.

    These images were further sharpened through image reconstruction techniques. The view is so crisp that one would have to stand on Io to see this much detail on Jupiter with the naked eye

  16. HUBBLE CLICKS IMAGES OF IO SWEEPING ACROSS JUPITER

    NASA Technical Reports Server (NTRS)

    2002-01-01

    While hunting for volcanic plumes on Io, NASA's Hubble Space Telescope captured these images of the volatile moon sweeping across the giant face of Jupiter. Only a few weeks before these dramatic images were taken, the orbiting telescope snapped a portrait of one of Io's volcanoes spewing sulfur dioxide 'snow.' These stunning images of the planetary duo are being released to commemorate the ninth anniversary of the Hubble telescope's launch on April 24, 1990. All of these images were taken with the Wide Field and Planetary Camera 2. The three overlapping snapshots show in crisp detail Io passing above Jupiter's turbulent clouds. The close-up picture of Io (bottom right) reveal a 120-mile-high (200-kilometer) plume of sulfur dioxide 'snow' emanating from Pillan, one of the moon's active volcanoes. 'Other observations have inferred sulfur dioxide 'snow' in Io's plumes, but this image offers direct observational evidence for sulfur dioxide 'snow' in an Io plume,' explains John R. Spencer of Lowell Observatory in Flagstaff, Ariz. A Trip Around Jupiter The three snapshots of the volcanic moon rounding Jupiter were taken over a 1.8-hour time span. Io is roughly the size of Earth's moon but 2,000 times farther away. In two of the images, Io appears to be skimming Jupiter's cloud tops, but it's actually 310,000 miles (500,000 kilometers) away. Io zips around Jupiter in 1.8 days, whereas the moon circles Earth every 28 days. The conspicuous black spot on Jupiter is Io's shadow and is about the size of the moon itself (2,262 miles or 3,640 kilometers across). This shadow sails across the face of Jupiter at 38,000 mph (17 kilometers per second). The smallest details visible on Io and Jupiter measure 93 miles (150 kilometers) across, or about the size of Connecticut. These images were further sharpened through image reconstruction techniques. The view is so crisp that one would have to stand on Io to see this much detail on Jupiter with the naked eye. The bright patches on Io

  17. Hubble Clicks Images of Io Sweeping Across Jupiter

    NASA Technical Reports Server (NTRS)

    1999-01-01

    While hunting for volcanic plumes on Io, NASA's Hubble Space Telescope captured these images of the volatile moon sweeping across the giant face of Jupiter. Only a few weeks before these dramatic images were taken, the orbiting telescope snapped a portrait of one of Io's volcanoes spewing sulfur dioxide 'snow.'

    These stunning images of the planetary duo are being released to commemorate the ninth anniversary of the Hubble telescope's launch on April 24, 1990. All of these images were taken with the Wide Field and Planetary Camera 2.

    The three overlapping snapshots show in crisp detail Io passing above Jupiter's turbulent clouds. The close-up picture of Io (bottom right) reveal a 120-mile-high (200-kilometer) plume of sulfur dioxide 'snow' emanating from Pillan, one of the moon's active volcanoes.

    'Other observations have inferred sulfur dioxide 'snow' in Io's plumes, but this image offers direct observational evidence for sulfur dioxide 'snow' in an Io plume,' explains John R. Spencer of Lowell Observatory in Flagstaff, Ariz.

    A Trip Around Jupiter

    The three snapshots of the volcanic moon rounding Jupiter were taken over a 1.8-hour time span. Io is roughly the size of Earth's moon but 2,000 times farther away. In two of the images, Io appears to be skimming Jupiter's cloud tops, but it's actually 310,000 miles (500,000 kilometers) away. Io zips around Jupiter in 1.8 days, whereas the moon circles Earth every 28 days.

    The conspicuous black spot on Jupiter is Io's shadow and is about the size of the moon itself (2,262 miles or 3,640 kilometers across). This shadow sails across the face of Jupiter at 38,000 mph (17 kilometers per second). The smallest details visible on Io and Jupiter measure 93 miles (150 kilometers) across, or about the size of Connecticut.

    These images were further sharpened through image reconstruction techniques. The view is so crisp that one would have to stand on Io to see this much detail on Jupiter with the naked eye

  18. HUBBLE CLICKS IMAGES OF IO SWEEPING ACROSS JUPITER

    NASA Technical Reports Server (NTRS)

    2002-01-01

    While hunting for volcanic plumes on Io, NASA's Hubble Space Telescope captured these images of the volatile moon sweeping across the giant face of Jupiter. Only a few weeks before these dramatic images were taken, the orbiting telescope snapped a portrait of one of Io's volcanoes spewing sulfur dioxide 'snow.' These stunning images of the planetary duo are being released to commemorate the ninth anniversary of the Hubble telescope's launch on April 24, 1990. All of these images were taken with the Wide Field and Planetary Camera 2. The three overlapping snapshots show in crisp detail Io passing above Jupiter's turbulent clouds. The close-up picture of Io (bottom right) reveal a 120-mile-high (200-kilometer) plume of sulfur dioxide 'snow' emanating from Pillan, one of the moon's active volcanoes. 'Other observations have inferred sulfur dioxide 'snow' in Io's plumes, but this image offers direct observational evidence for sulfur dioxide 'snow' in an Io plume,' explains John R. Spencer of Lowell Observatory in Flagstaff, Ariz. A Trip Around Jupiter The three snapshots of the volcanic moon rounding Jupiter were taken over a 1.8-hour time span. Io is roughly the size of Earth's moon but 2,000 times farther away. In two of the images, Io appears to be skimming Jupiter's cloud tops, but it's actually 310,000 miles (500,000 kilometers) away. Io zips around Jupiter in 1.8 days, whereas the moon circles Earth every 28 days. The conspicuous black spot on Jupiter is Io's shadow and is about the size of the moon itself (2,262 miles or 3,640 kilometers across). This shadow sails across the face of Jupiter at 38,000 mph (17 kilometers per second). The smallest details visible on Io and Jupiter measure 93 miles (150 kilometers) across, or about the size of Connecticut. These images were further sharpened through image reconstruction techniques. The view is so crisp that one would have to stand on Io to see this much detail on Jupiter with the naked eye. The bright patches on Io

  19. Hot Jupiter with Hidden Water (Artist Concept)

    NASA Image and Video Library

    2016-06-08

    Hot Jupiters, exoplanets around the same size as Jupiter that orbit very closely to their stars, often have cloud or haze layers in their atmospheres. This may prevent space telescopes from detecting atmospheric water that lies beneath the clouds, according to a study in the Astrophysical Journal. As much as half of the water in the atmospheres of these exoplanets may be blocked by these clouds or hazes, research suggests. The study, led by researchers at NASA's Jet Propulsion Laboratory, Pasadena, California, examined hot Jupiters that had been observed with the Hubble Space Telescope. http://photojournal.jpl.nasa.gov/catalog/PIA20687

  20. Document delivery by the Jupiter Library Consortium

    NASA Technical Reports Server (NTRS)

    Wessels, Robert H. A.

    1994-01-01

    The Jupiter library consortium consists of 4 of the leading libraries in the Netherlands. During 1993 Jupiter received 600,000 requests for copies of journal articles, or 70 percent of all external article requests in the Netherlands. Over 90 percent of the requested documents were delivered from a collection of 40,000 current international journal subscriptions. Jupiter and its affiliate libraries are non-profit organizations belonging to, and serving, the scientific and technical research community. The usage of the current journal collection of the libraries was analyzed to improve the cost/benefit ratio.

  1. (abstract) Galileo Navigation: Launch to Jupiter Orbit

    NASA Technical Reports Server (NTRS)

    D'Amario, Louis A.

    1997-01-01

    The Galileo spacecraft was launched on October 18, 1989. After a 3.7 billion kilometer journey lasting just over six years, the Galileo Orbiter and Probe arrived at Jupiter on December 7, 1995. The atmospheric Probe survived its atmospheric entry and successfully transmitted data to the Orbiter flying overhead. To date, the Orbiter has successfully completed the first three of the ten planned satellite encounters. Navigation for the Galileo Mission has proved to be a unique and challenging task. The challenges and results of navigating Galileo through the interplanetary transfer to Jupiter, delivery of the atmospheric entry Probe, Jupiter orbit insertion, and the orbital tour are presented in this paper.

  2. Juno's first glimpse of Jupiter's complexity

    NASA Astrophysics Data System (ADS)

    Bolton, Scott; Levin, Steven; Bagenal, Fran

    2017-08-01

    Preliminary results from NASA's Juno mission are presented in this special issue of Geophysical Research Letters. The data were gathered by nine scientific instruments as the Juno spacecraft approached Jupiter on the dawn flank, was inserted into Jupiter orbit on 4 July 2016, and made the first polar passes close to the planet. The first results hint that Jupiter may not have a distinct core, indicate puzzling deep atmospheric convection, and reveal complex small-scale structure in the magnetic field and auroral processes that are distinctly different from those at Earth.

  3. Overview of Juno Results at Jupiter

    NASA Astrophysics Data System (ADS)

    Bolton, Scott; Connerney, Jack; Levin, Steve

    2017-04-01

    Juno is the first mission to investigate Jupiter using a close polar orbit. The Juno science goals include the study of Jupiter interior composition and structure, deep atmosphere and its polar magnetosphere. All orbits have peri-jove at approximately 5000 km above Jupiter's visible cloud tops. The payload consists of a set of microwave antennas for deep sounding, magnetometers, gravity radio science, low and high energy charged particle detectors, plasma wave antennas, ultraviolet imaging spectrograph, infrared imager and spectrometer and a visible camera. The Juno mission design, an overview of the early science results from Juno, and a description of the collaborative Earth based campaign will be presented.

  4. Laboratory Investigations of Jupiter's Chromophores

    NASA Astrophysics Data System (ADS)

    Carlson, Robert W.; Baines, K. H.

    2009-09-01

    Ultraviolet- irradiated ammonium hydrosulfide (NH4SH) ice and its byproducts have long been postulated to be the source of the reddish coloring of the Great Red Spot (e,g., Lewis and Prinn (1970), West et al., 1986, Baines et al., 2004). NH4SH aerosols created near the 2.5-bar level on Jupiter may be transported upward to the 300-mbar level in the anti-cylonic environment of the Great Red Spot, where they are then subjected to solar ultraviolet irradiation. The irradiated ices and byproducts could be concentrated by the vortex action of the GRS, enhancing the reddish color above that which would be seen by an irradiated NH4SH cloud in the typical zone/belt structure of Jupiter. We have initiated an experimental study of potential sulfurous chromophores using a photolysis flow cell with temperatures and pressures controlled to simulate Jovian conditions. Photolysis is produced using Hg, Zn, or D2 lamps, each with different spectral characteristics. Analysis of the photoproducts is performed using ultraviolet, visible, and infrared spectroscopy and the gaseous and sublimed products are also characterized using mass spectroscopy. Our first experiments have been with NH4SH condensed from mixtures of NH3 and H2S at 240 K. The irradiated condensate exhibits broad ultraviolet and visible features that may be attributed to absorptions by polysulfide ions (SnS2-) in ammonium polysulfide [(NH4+)2 SnS2-] and possibly to absorptions by hydropolysulfide ions (HSnS-). The measurements and comparisons to Jovian spectra will be presented.

  5. New Views of Jupiter's Rings

    NASA Astrophysics Data System (ADS)

    Burns, J. A.

    1998-09-01

    Jupiter's rings are the archetype of ethereal planetary rings (very-low optical-depth bands containing micron-sized "dust"). As a result of much improved observations by Galileo (Ockert-Bell* -- most citations are et al. and Icarus in press* or this meeting) and Keck (de Pater*), we now understand the nature of such rings. The ring has three components: a 104 km-thick toroidal halo (1.4-1.7 RJ; normal optical depth t = 10-6), a thin main ring (1.7-1.8 RJ; t = 10-6), and a pair of exterior gossamer rings (1.8-3.5RJ; t = 10-7). The main ring has patchy ( 20-30 percent) brightness. The ring is reddish and its particles satisfy a -2.5 differential power-law size distribution. Because particle lifetimes are brief, the rings must be continually regenerated, by collisions into parent bodies, which may be unseen or may be the known small ring-moons (Thomas*, Simonelli). The gossamer ring seems to be collisional ejecta derived from the ring-moons Amalthea and Thebe, and evolving inward by Poynting-Robertson drag (Burns). The particles drift through many electromagnetic resonances, clustering around synchronous orbit, which produce jumps in the particles' inclinations (Hamilton). The main ring is probably debris from Adrastea and Metis, which orbit in the equatorial plane. The halo particles are driven vertically by electromagnetic forces, which may be resonant (Schaffer & Burns) or not (Horanyi & Cravens). When halo orbits become highly distorted, particles are lost into Jupiter. Similar faint rings may be attendant to all small, close-in satellites (Showalter).

  6. A New Look at Jupiter: Results at the Now Frontier. [Pioneer 10, interplanetary space, and Jupiter atmosphere

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Pioneer 10's encounter with Jupiter is discussed along with the interplanetary space beyond the orbit of Mars. Other topics discussed include the size of Jupiter, the Galilean satellites, the magnetic field of Jupiter, radiation belts, Jupiter's weather and interior, and future exploration possibilities. Educational projects are also included.

  7. Extreme all-cause mortality in JUPITER requires reexamination of vital records.

    PubMed

    Serebruany, Victor L

    2011-01-01

    To compare all-cause mortality in JUPITER with other statin trials at 21 months of follow-up. Outcome advantages including all-cause mortality reduction yielded from the JUPITER trial support aggressive use of rosuvastatin and, perhaps by extension, other statins for primary prevention. Despite enrolling apparently healthy subjects and early trial termination at 21 months of mean follow-up, JUPITER revealed very high all-cause mortality in both the placebo (2.8%) and rosuvastatin (2.2%) arms. Comparison of all-cause mortality prorated for 21 months in 10 primary prevention studies and 1 acute coronary syndromes statin trial. The all-cause mortality in JUPITER was more than twice that of the average of primary prevention studies, matching well only with specific trials designed in diabetics (ASPEN or CARDS), early hypertension studies (ALLHAT-LLT) or a trial in patients with acute coronary syndromes (PROVE IT). Since the 'play of chance' is unlikely to explain these discrepancies due to excellent baseline match, excess death rates and all-cause mortality rates in both JUPITER arms must be questioned. It may be important that the study sponsor self-monitored sites. Excess all-cause mortality rates in the apparently relatively healthy JUPITER population are alarming and require independent verification. If, indeed, the surprising outcomes in JUPITER are successfully challenged, and considering established harm of statins with regard to rhabdomyolysis as well as, potentially, diabetes, millions of patients may find better and safer options for primary prevention of vascular events. Copyright © 2011 S. Karger AG, Basel.

  8. Lost in the Shadow of Jupiter: The Effects of Ring Particle Charging

    NASA Astrophysics Data System (ADS)

    Hamilton, Douglas P.; Jontof-Hutter, D.

    2012-05-01

    Micrometeoroid impacts onto tiny moonlets embedded in Jupiter's dusty rings replenish the rings with grains of all sizes. These grains become electrically charged from interactions with the ambient plasma and solar photons, and their orbital motions are dominated by gravity and the electromagnetic force arising from Jupiter's rotating magnetic field. For even the simplest case of constant electric charge, this combination of forces causes both radial and vertical dynamical instabilities. When the gravitational and electromagnetic forces are comparable, positively-charged dust grains are driven to either crash into Jupiter or escape from the planet depending on their launch distance. Some smaller grains of either charge are vertically unstable, climbing up local magnetic field lines to collide with Jupiter. We understand the origin of both instabilities and have derived the relevant stability boundaries analytically (Jontof-Hutter and Hamilton 2012). Further dynamical instabilities arise when charges vary with time due to, for example, a dust grain's periodic transit through Jupiter's shadow which temporarily interrupts photoelectric currents. The eccentricities of large grains, which react nearly instantly to changes in the charging environment, are excited enough to explain the faint outward extension of Jupiter's Thebe ring (Hamilton and Krueger 2008). We expand our investigation by exploring the effect of Jupiter's shadow on dust grains of all sizes, both inside and outside synchronous orbit. The shadow extends the radial instability zones discussed above to both larger and smaller dust grains. The removal of larger grains is limited by the few-year orbital precession timescale. Smaller grains, which react slowly to differing charging conditions, suffer forces that are alternatively stabilizing and destabilizing if their electric potentials change sign. These grains evolve chaotically and most eventually become unstable.

  9. Effects of Magnetism on the Atmospheres and Evolution of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Rogers, Tamara M.; Barman, Travis S.; Showman, Adam P.; Youdin, Andrew N.

    2014-11-01

    Magnetic effects imprint potentially observable features of close-in extrasolar giant planets, or "hot Jupiters," through two mechanisms: the Lorentz force, which modifies atmospheric dynamics, and Ohmic dissipation, which may have a large impact on the structure and evolution of a planet. We present results from a 3D anelastic magnetohydrodynamic (MHD) model, taking into account purely resistive MHD. We demonstrate that magnetic effects may cause a transition from the expected superrotation in purely hydrodynamic models to subrotation (i.e. wind reversal) at high equilibrium temperatures and magnetic field strengths. This reduction of wind speeds correspondingly reduces hot spot displacement, forcing MHD atmospheric hot spots to be found westward of their hydrodynamic counterparts. For the case of HD 209458b, we do not expect that atmospheric Ohmic dissipation has a large enough magnitude to explain its observed radius, even when scaling the dissipated power into the planetary convective zone. However, the efficacy of Ohmic dissipation is expected to be greater for hot Jupiters with a lower mass than HD 209458b, as these planets have less partial degeneracy and larger pressure scale heights. Hence, Ohmic dissipation can likely explain why a subset of transiting hot Jupiters appear inflated, but other mechanisms may be required to explain those with a mass comparable to or greater than 0.7 Jupiter masses.

  10. Kepler constraints on planets near hot Jupiters

    SciTech Connect

    Steffen, Jason H.; Ragozzine, Darin; Fabrycky, Daniel C.; Carter, Joshua A.; Ford, Eric B.; Holman, Matthew J.; Rowe, Jason F.; Welsh, William F.; Borucki, William J.; Boss, Alan P.; Ciardi, David R.; /Caltech /Harvard-Smithsonian Ctr. Astrophys.

    2012-05-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2:1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  11. Juno Captures the Roar of Jupiter

    NASA Image and Video Library

    2016-06-30

    NASA's Juno spacecraft has crossed into Jupiter's immense magnetic field. Juno's Waves instrument recorded the crossing of the bow shock on June 24, 2016, represented by the following animation and sound.

  12. Features of Jupiter Great Red Spot

    NASA Image and Video Library

    1997-09-07

    This montage features activity in the turbulent region of Jupiter Great Red Spot GRS. Four sets of images of the GRS were taken by NASA Galileo imaging system over an 11.5 hour period on 26 June, 1996.

  13. HCN and chromophore formation on Jupiter

    NASA Technical Reports Server (NTRS)

    Ferris, James P.; Ishikawa, Yoji

    1987-01-01

    Reaction paths for the formation of HCN and chromophores on Jupiter are suggested. The reactions involve photolysis of ammonia/acetylene mixtures. Experimental data supporting these pathways are reported.

  14. Kepler constraints on planets near hot Jupiters

    PubMed Central

    Steffen, Jason H.; Ragozzine, Darin; Fabrycky, Daniel C.; Carter, Joshua A.; Ford, Eric B.; Holman, Matthew J.; Rowe, Jason F.; Welsh, William F.; Borucki, William J.; Boss, Alan P.; Ciardi, David R.; Quinn, Samuel N.

    2012-01-01

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 2∶1 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history. PMID:22566651

  15. Distribution of Water in Jupiter Stratosphere

    NASA Image and Video Library

    2013-04-23

    This map shows the distribution of water in the stratosphere of Jupiter as measured with the Herschel space observatory. White and cyan indicate highest concentration of water, and blue indicates lesser amounts.

  16. Juno Arrival at Jupiter Artist Concept

    NASA Image and Video Library

    2015-07-07

    This artist's rendering shows NASA's Juno spacecraft making one of its close passes over Jupiter. Launched in 2011, the Juno spacecraft will arrive at Jupiter in 2016 to study the giant planet from an elliptical, polar orbit. Juno will repeatedly dive between the planet and its intense belts of charged particle radiation, traveling from pole to pole in about an hour, and coming within 5,000 kilometers (about 3,000 miles) of the cloud tops at closest approach. Juno's primary goal is to improve our understanding of Jupiter's formation and evolution. The spacecraft will spend a little over a year investigating the planet's origins, interior structure, deep atmosphere and magnetosphere. Juno's study of Jupiter will help us to understand the history of our own solar system and provide new insight into how planetary systems form and develop in our galaxy and beyond. http://photojournal.jpl.nasa.gov/catalog/PIA19639

  17. Another View of June Fireball at Jupiter

    NASA Image and Video Library

    Amateur astronomer Christopher Go, of Cebu, Philippines, captured this video of a fireball burning up in the Jupiter atmosphere on June 3, 2010. Go recorded the video at 55 frames per second in blu...

  18. Voyager spacecraft images of Jupiter and Saturn.

    PubMed

    Birnbaum, M M

    1982-01-15

    The images of Jupiter and Saturn and their satellites taken by the Voyager spacecraft TV cameras are shown and described. The scientific findings of the Voyager mission instruments and experiments are summarized.

  19. The D/H ratio for Jupiter

    NASA Astrophysics Data System (ADS)

    Smith, Wm. H.; Schempp, W. V.; Baines, K. H.

    1989-01-01

    Observations of Jupiter's spectrum near the R5(0) HD line at 6063.88 A are reported. A feature with an equivalent width of 0.065 + or - 0.021 mA is coincident with the expected line. This feature is compared with HD profiles computed for inhomogeneous scattering models for Jupiter to yield a range for the Jovian D/H ratio of 1.0-2.9 x 10 to the -5th. This D/H ratio is in the lower range of previously reported D/H values for Jupiter and corresponds to an essentially solar D/H ratio for Jupiter. The detection of HD features in the presence of probable blends with spectral features of minor atmospheric hydrocarbon molecules is discussed. Such blends may make unambiguous identification of HD features difficult.

  20. Juno celebrates a year at Jupiter

    NASA Astrophysics Data System (ADS)

    Bolton, Scott J.

    2017-07-01

    NASA's Juno mission to Jupiter has just returned its early science results after spending a year orbiting the 'King of the Solar System'. Principal Investigator Scott Bolton summarizes what we have learnt.

  1. Kepler constraints on planets near hot Jupiters.

    PubMed

    Steffen, Jason H; Ragozzine, Darin; Fabrycky, Daniel C; Carter, Joshua A; Ford, Eric B; Holman, Matthew J; Rowe, Jason F; Welsh, William F; Borucki, William J; Boss, Alan P; Ciardi, David R; Quinn, Samuel N

    2012-05-22

    We present the results of a search for planetary companions orbiting near hot Jupiter planet candidates (Jupiter-size candidates with orbital periods near 3 d) identified in the Kepler data through its sixth quarter of science operations. Special emphasis is given to companions between the 21 interior and exterior mean-motion resonances. A photometric transit search excludes companions with sizes ranging from roughly two-thirds to five times the size of the Earth, depending upon the noise properties of the target star. A search for dynamically induced deviations from a constant period (transit timing variations) also shows no significant signals. In contrast, comparison studies of warm Jupiters (with slightly larger orbits) and hot Neptune-size candidates do exhibit signatures of additional companions with these same tests. These differences between hot Jupiters and other planetary systems denote a distinctly different formation or dynamical history.

  2. On the speed of gravity and the jupiter/quasar measurement

    SciTech Connect

    Samuel, Stuart

    2004-08-15

    I present the theory and analysis behind the experiment by Fomalont and Kopeikin involving Jupiter and quasar J0842 + 1845 that purported to measure the speed of gravity. The computation of the v{sub J}/c correction to the gravitational time delay difference relevant to the experiment is derived, where v{sub J} is the speed of Jupiter as measured from Earth. Since the v{sub J}/c corrections are too small to have been measured in the Jupiter/quasar experiment, it is impossible that the speed of gravity was extracted from the data, and I explain what went wrong with the data analysis. Finally, mistakes are shown in papers by Fomalont and Kopeikin intended to rebut my work and the work of others.

  3. Satellite Footprints Seen in Jupiter Aurora

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This is a spectacular NASA Hubble Space Telescope close-up view of an electric-blue aurora that is eerily glowing one half billion miles away on the giant planet Jupiter. Auroras are curtains of light resulting from high-energy electrons racing along the planet's magnetic field into the upper atmosphere. The electrons excite atmospheric gases, causing them to glow. The image shows the main oval of the aurora, which is centered on the magnetic north pole, plus more diffuse emissions inside the polar cap.

    Though the aurora resembles the same phenomenon that crowns Earth's polar regions, the Hubble image shows unique emissions from the magnetic 'footprints' of three of Jupiter's largest moons. (These points are reached by following Jupiter's magnetic field from each satellite down to the planet).

    Auroral footprints can be seen in this image from Io (along the lefthand limb), Ganymede (near the center), and Europa (just below and to the right of Ganymede's auroral footprint). These emissions, produced by electric currents generated by the satellites, flow along Jupiter's magnetic field, bouncing in and out of the upper atmosphere. They are unlike anything seen on Earth.

    This ultraviolet image of Jupiter was taken with the Hubble Space Telescope Imaging Spectrograph (STIS) on November 26, 1998. In this ultraviolet view, the aurora stands out clearly, but Jupiter's cloud structure is masked by haze.

    December 14, 2000 inaugurates an intensive two weeks of joint observation of Jupiter's aurora by Hubble and the Cassini spacecraft. Cassini will make its closest approach to Jupiter enroute to a July 2004 rendezvous with Saturn. A second campaign in January 2001 will consist of Hubble images of Jupiter's day-side aurora and Cassini images of Jupiter's night-side aurora, obtained just after Cassini has flown past Jupiter. The team will develop computer models that predict how the aurora operates, and this will yield new insights into the effects of the solar wind

  4. Significant Science at Jupiter Using Solar Power

    NASA Technical Reports Server (NTRS)

    Reitsema, H. J.; Smith, E. J.; Spilker, T.; Reinert, R.

    2001-01-01

    Missions to the Outer Planets are challenging for a number of reasons, primary of which is the low output of solar arrays at large heliocentric distances. The INSIDE Jupiter mission is a Discovery concept for a science investigation at Jupiter that is capable of producing major studies of the Jovian internal structure and ionospheric-magnetospheric coupling. Additional information is contained in the original extended abstract.

  5. New Changes in Jupiter Great Red Spot

    NASA Image and Video Library

    2015-10-13

    This image is one of two images from NASA Hubble Space Telescope comparing the movement of Jupiter clouds. The movement of Jupiter's clouds can be seen by comparing the first map to the second one in this animated pair of images. Zooming in on the Great Red Spot at blue (below, at left) and red (below, at right) wavelengths reveals a unique filamentary feature not previously seen. http://photojournal.jpl.nasa.gov/catalog/PIA19648

  6. Significant Science at Jupiter Using Solar Power

    NASA Technical Reports Server (NTRS)

    Reitsema, H. J.; Smith, E. J.; Spilker, T.; Reinert, R.

    2001-01-01

    Missions to the Outer Planets are challenging for a number of reasons, primary of which is the low output of solar arrays at large heliocentric distances. The INSIDE Jupiter mission is a Discovery concept for a science investigation at Jupiter that is capable of producing major studies of the Jovian internal structure and ionospheric-magnetospheric coupling. Additional information is contained in the original extended abstract.

  7. Voyager-Jupiter radio science data papers

    NASA Technical Reports Server (NTRS)

    Levy, G. S.; Wood, G. E.

    1980-01-01

    The reduction and interpretation of the radio science data from the Voyager 1 and 2 encounters of the planet Jupiter and its satellites resulted in the preparation of several papers for publication in the special Voyager-Jupiter issue of the Journal of Geophysical Research. The radio science and tracking systems of the Deep Space Network provide the data which makes this research possible. This article lists submitted papers by title, with their authors and with abstracts of their contents.

  8. Europa, taken from Voyager 1 to Jupiter

    NASA Image and Video Library

    1979-03-01

    Range : 5.9 million kilometers (3.66 million miles) Europa is Jupiter's 2nd Galilean satellites from the planet and the brightest. Photo taken early morning through violet filter. Faint swirls and linear patterns show in the equatorial region (which shows darker than the poles). This hemisphere always faces Jupiter. North is up. Density and size comparable to Earth's Moon and seems to show water ice or ground water on its surface. JPL Reference # P-21163.

  9. Jupiter's Radiation Belts: Can Pioneer 10 Survive?

    PubMed

    Hess, W N; Birmingham, T J; Mead, G D

    1973-12-07

    Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft.

  10. Voyager-Jupiter radio science data papers

    NASA Technical Reports Server (NTRS)

    Levy, G. S.; Wood, G. E.

    1980-01-01

    The reduction and interpretation of the radio science data from the Voyager 1 and 2 encounters of the planet Jupiter and its satellites resulted in the preparation of several papers for publication in the special Voyager-Jupiter issue of the Journal of Geophysical Research. The radio science and tracking systems of the Deep Space Network provide the data which makes this research possible. This article lists submitted papers by title, with their authors and with abstracts of their contents.

  11. Jupiter's radiation belts: Can Pioneer 10 survive?

    NASA Technical Reports Server (NTRS)

    Hess, W. N.; Birmingham, T. J.; Mead, G. D.

    1973-01-01

    Model calculations of Jupiter's electron and proton radiation belts indicate that the Galilean satellites can reduce particle fluxes in certain regions of the inner magnetosphere by as much as six orders of magnitude. Average fluxes should be reduced by a factor of 100 or more along the Pioneer 10 trajectory through the heart of Jupiter's radiation belts in early December. This may be enough to prevent serious radiation damage to the spacecraft.

  12. Tidal dissipation and obliquity evolution in hot Jupiter systems

    SciTech Connect

    Valsecchi, Francesca; Rasio, Frederic A.

    2014-05-10

    Two formation scenarios have been proposed to explain the tight orbits of hot Jupiters. They could be formed in orbits with a small inclination (with respect to the stellar spin) via disk migration, or in more highly inclined orbits via high-eccentricity migration, where gravitational interactions with a companion and tidal dissipation are at play. Here we target hot Jupiter systems where the misalignment λ has been inferred observationally and we investigate whether their properties are consistent with high-eccentricity migration. Specifically, we study whether stellar tides can be responsible for the observed distribution of λ and orbital separations. Improving on previous studies, we use detailed models for each star, thus accounting for how convection (and tidal dissipation) depends on stellar properties. In line with observations suggesting that hotter stars have higher λ, we find that λ increases as the amount of stellar surface convection decreases. This trend supports the hypothesis that tides are the mechanism shaping the observed distribution of λ. Furthermore, we study the past orbital evolution of five representative systems, chosen to cover a variety of temperatures and misalignments. We consider various initial orbital configurations and integrate the equations describing the coupled evolution of the orbital separation, stellar spin, and misalignment. We account for stellar tides and wind mass loss, stellar evolution, and magnetic braking. We show that the current properties of these five representative systems can be explained naturally, given our current understanding of tidal dissipation and with physically motivated assumptions for the effects driving the orbital evolution.

  13. A Searchlight Beam Model of Jupiter's Decametric Radio Emissions

    NASA Astrophysics Data System (ADS)

    Imai, K.; Garcia, L.; Reyes, F.; Imai, M.; Thieman, J. R.; Ikuta, M.

    2008-12-01

    It has long been recognized that there is a marked long-term periodic variation in Jupiter's integrated radio occurrence probability. The period of the variation is on the order of a decade. Carr et al. [1970] showed that such variations are much more closely correlated with Jovicentric declination of the Earth (De). The range of the smoothed variation of De is from approximately +3.3 to -3.3 degrees. This De effect was extensively studied and confirmed by Garcia [1996]. It shows that the occurrence probability of the non-Io-A source is clearly controlled by De at 18, 20, and 22 MHz during the 1957-1994 apparitions. We propose a new model to explain the De effect. This new model shows that the beam structure of Jupiter radio emissions, which has been thought of like a hollow-cone, has a narrow beam like a searchlight, which can be explained by assuming that the three dimensional shape of the radio source expands along the line of the magnetic field. Various computer graphics illustrate the concept of this searchlight beam model.

  14. Chandra Image Reveals Auroral X-rays at Poles of Jupiter

    NASA Technical Reports Server (NTRS)

    2000-01-01

    This Chandra image of Jupiter shows concentrations of aurora x-rays near the north and south poles due to a single `hot spot' that pulsates with a period of 45 minutes, similar to high-latitude radio pulsation previously detected by NASA's Galileo and Cassini spacecraft. Previous x-ray detections of Jupiter have been made with other x-ray telescopes, but did not reveal that the sources of the x-rays, energetic oxygen and sulfur ions, would be located so near the poles. Previous theories held that ions were mostly coming from Jupiter's moon, lo. Chandra's ability to pinpoint the source of the x-rays discards this theory since ions coming from near lo's orbit carnot reach the observed high latitudes. One possibility is that particles flowing out from the Sun are captured in the outer regions of Jupiter's magnetic field, then accelerated and directed toward its magnetic pole. Once captured, the ions would bounce back and forth in the magnetic field from Jupiter's north pole to the south pole in an oscillating motion that could explain the pulsation.

  15. Jupiter in True and False Color

    NASA Technical Reports Server (NTRS)

    2001-01-01

    These color composite frames of the mid-section of Jupiter were of narrow angle images acquired on December 31, 2000, a day after Cassini's closest approach to the planet. The smallest features in these frames are roughly 60 kilometers. The left is natural color, composited to yield the color that Jupiter would have if seen by the naked eye. The right frame is composed of 3 images: two were taken through narrow band filters centered on regions of the spectrum where the gaseous methane in Jupiter's atmosphere absorbs light, and the third was taken in a red continuum region of the spectrum, where Jupiter has no absorptions. The combination yields an image whose colors denote the height of the clouds. Red regions are deep water clouds, bright blue regions are high haze (like the blue covering the Great Red Spot). Small, intensely bright white spots are energetic lightning storms which have penetrated high into the atmosphere where there is no opportunity for absorption of light: these high cloud systems reflect all light equally. The darkest blue regions -- for example, the long linear regions which border the northern part of the equatorial zone, are the very deep 'hot spots', seen in earlier images, from which Jovian thermal emission is free to escape to space. This is the first time that global images of Jupiter in all the methane and attendant continuum filters have been acquired by a spacecraft. From images like these, the stratigraphy of Jupiter's dynamic atmosphere will be determined.

  16. Hubble Provides Complete View of Jupiter's Auroras

    NASA Technical Reports Server (NTRS)

    1998-01-01

    NASA's Hubble Space Telescope has captured a complete view of Jupiter's northern and southern auroras.

    Images taken in ultraviolet light by the Space Telescope Imaging Spectrograph (STIS) show both auroras, the oval-shaped objects in the inset photos. While the Hubble telescope has obtained images of Jupiter's northern and southern lights since 1990, the new STIS instrument is 10 times more sensitive than earlier cameras. This allows for short exposures, reducing the blurring of the image caused by Jupiter's rotation and providing two to five times higher resolution than earlier cameras. The resolution in these images is sufficient to show the 'curtain' of auroral light extending several hundred miles above Jupiter's limb (edge). Images of Earth's auroral curtains, taken from the space shuttle, have a similar appearance. Jupiter's auroral images are superimposed on a Wide Field and Planetary Camera 2 image of the entire planet. The auroras are brilliant curtains of light in Jupiter's upper atmosphere. Jovian auroral storms, like Earth's, develop when electrically charged particles trapped in the magnetic field surrounding the planet spiral inward at high energies toward the north and south magnetic poles. When these particles hit the upper atmosphere, they excite atoms and molecules there, causing them to glow (the same process acting in street lights).

    The electrons that strike Earth's atmosphere come from the sun, and the auroral lights remain concentrated above the night sky in response to the 'solar wind.'

  17. Searching for comets encountering Jupiter: First campaign

    NASA Astrophysics Data System (ADS)

    Tancredi, G.; Lindgren, M.

    1994-02-01

    This paper reports results from a first search for previously undetected comets in the vicinity of Jupiter. Combining these with a model for the probability for finding a comet in this region we estimate the total number of comets in the Jupiter family. Thirty-six Schmidt plates were obtained at ESO in March and April 1992. We searched the plates down to a limiting nuclear B-magnitude of 13.8. No comet was found. This result, together with a model for the probability of finding a comet close to Jupiter, yields an upper estimate of the number of objects in the Jupiter family. If we assume that the comets are inactive at approximately 5 AU from the Sun, we get a conservative estimate of N(HBN less than 13.8) less than 210. We discuss the possible brightening due to activity and present estimates including this effect. By assuming a certain magnitude distribution, we then compare our results with previous attempts to estimate the total size of the Jupiter family. Although our estimates are still higher than previous values, our results are independent of the distribution of comets with perihelion distance. Ongoing and future searches with the same technique will further constrain the population size of the Jupiter family.

  18. The Jupiter Ganymede Orbiter : An ESA Contribution to the Europa-Jupiter System Mission

    NASA Astrophysics Data System (ADS)

    Drossart, Pierre; Blanc, M.; Lebreton, J. P.; Pappalardo, R. T.; Greeley, R.; Fujimoto, M.; EJSM/Jupiter Science Definition Team

    2008-09-01

    In the framework of an outer planets mission, under study after the NASA-Juno mission, the Europa-Jupiter System Mission (EJSM) would combine a fleet of up to three satellites in order to investigate in depth many questions related to the Jupiter System. These investigations are essential for our understanding of the emergence and evolution of habitable worlds, not only within the Solar System, but also for extrasolar planets investigations. Scientific targets of EJSM will focus on Europa and Ganymede as a key pair of Galilean satellites, to address the questions on their habitability, formation, and internal structure, as well as the coupling with the whole Jovian system : Jupiter's atmosphere and interior, magnetosphere and magnetodisk. .In combination with a Jupiter Europa Orbiter (JEO likely provided by NASA) and a Jupiter Magnetospheric Orbiter (JMO likely provided by JAXA), ESA is studying a Jupiter Ganymede Orbiter (JGO). The mission scenario includes a direct launch in 2020 with a transfer time to Jupiter of 6 years. After the orbit insertion around Jupiter, a first phase ( 2 years) will be devoted to Jupiter system and Callisto studies, with multiple flybys of Callisto planned at low altitude ( 200 km), followed by a Ganymede orbit insertion and extensive study of Ganymede ( 1 year). In-depth comparative study of inner (Io and Europa) and outer (Ganymede and Callisto) satellites with combined payload of JEO and JGO will address the question of the relative geological evolution of the satellites. On JGO, the transport phenomena in the magnetosphere of Jupiter will be studied in combination with JMO, and the Ganymede magnetosphere will be observed in situ. Jupiter atmosphere investigations on JGO will focus on coupling phenomena between troposphere, stratosphere and mesosphere, the stratospheric composition and the question of thermospheric heating.

  19. Jupiter's Multi-level Clouds

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Clouds and hazes at various altitudes within the dynamic Jovian atmosphere are revealed by multi-color imaging taken by the Near-Infrared Mapping Spectrometer (NIMS) onboard the Galileo spacecraft. These images were taken during the second orbit (G2) on September 5, 1996 from an early-morning vantage point 2.1 million kilometers (1.3 million miles) above Jupiter. They show the planet's appearance as viewed at various near-infrared wavelengths, with distinct differences due primarily to variations in the altitudes and opacities of the cloud systems. The top left and right images, taken at 1.61 microns and 2.73 microns respectively, show relatively clear views of the deep atmosphere, with clouds down to a level about three times the atmospheric pressure at the Earth's surface.

    By contrast, the middle image in top row, taken at 2.17 microns, shows only the highest altitude clouds and hazes. This wavelength is severely affected by the absorption of light by hydrogen gas, the main constituent of Jupiter's atmosphere. Therefore, only the Great Red Spot, the highest equatorial clouds, a small feature at mid-northern latitudes, and thin, high photochemical polar hazes can be seen. In the lower left image, at 3.01 microns, deeper clouds can be seen dimly against gaseous ammonia and methane absorption. In the lower middle image, at 4.99 microns, the light observed is the planet's own indigenous heat from the deep, warm atmosphere.

    The false color image (lower right) succinctly shows various cloud and haze levels seen in the Jovian atmosphere. This image indicates the temperature and altitude at which the light being observed is produced. Thermally-rich red areas denote high temperatures from photons in the deep atmosphere leaking through minimal cloud cover; green denotes cool temperatures of the tropospheric clouds; blue denotes cold of the upper troposphere and lower stratosphere. The polar regions appear purplish, because small-particle hazes allow leakage and

  20. Transits and Occultations of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Haynes, Korey

    Since the first discovery of an extrasolar planet less than two decades ago, astronomers have learned how to measure not only the masses, radii, and orbital elements of a wide range exoplanets (far exceeding the parameters of our own solar system), but also their atmospheric temperatures and chemical compositions. Even with plentiful observations, many questions remain unanswered. Measuring atmospheric abundances based on observed absorption features can answer questions about carbon-to-oxygen (C/O) ratios, but many of the literature results rely on broadband photometry, where multiple absorption features become blended, thus complicating interpretation. Combining measurements across a long spectral baseline using multiple different instruments can be a powerful lever for studying the spectral energy distributions (SEDs) of exoplanets, but there is often a lack of consensus between observing teams and instruments. Some differences may be due to genuine temporal variations in the exoplanet atmospheres, while others are more likely due to differences in instrument characterization and data analysis. Resolved spectra of exoplanets, particularly in the infrared, where strong features due to water, carbon monoxide, carbon dioxide, and methane are expected, could break model degeneracies and answer many questions about C/O ratios and pressure-temperature atmospheric structures. While not the first, Wide Field Camera 3 (WFC3) on the Hubble Space Telescope is the only current space-based opportunity to study spectrally resolved exoplanet atmospheres in the infrared. We focus on hot Jupiter type exoplanets, and use WFC3 (as well as ancillary data from Spitzer and ground based facilities) to try to break degeneracies between models, resolve past observing conflicts, and unambiguously determine these planets' atmospheric composition and structure. We discover unambiguous detections of water in exoplanet atmospheres, and the first spectroscopic evidence for a temperature

  1. Using Jupiter's Synchrotron Radiation as a Probe into Jupiter's Inner Radiation Belts

    NASA Technical Reports Server (NTRS)

    Bolton, S. J.; Gulkis, S.; Klein, M. J.; Thorne, R. M.

    1995-01-01

    The Jovian decimetric emission is caused by the combined emission of synchrotron radiation originating from the relativistic electrons trapped in Jupiter's 'Van Allen radiation belts' and thermal emission from the planet's atmosphere. Synchrotron radiation characteristics and variations (which provides insight into the physical properties of Jupiter's inner radiation belts) will be amplified and discussed.

  2. Formation of Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; Young, Richard E. (Technical Monitor)

    1998-01-01

    An overview of current theories of the formation of our Solar System, with emphasis on giant planets, is presented. The most detailed models are based upon observations of planets and smaller bodies within our own Solar System and of young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Larger disk mass allows for faster growth of solid planetary bodies. The ability of a solid planet to trap gas from the protoplanetary disk increases rapidly as its mass increases (because the depth of its gravitational potential well increases), but decreases as the planetesimal accretion rate is increased (as it becomes hotter). The net effect of increasing disk mass is that gas giant planets form more rapidly, but with larger core masses. Observations of circumstellar disks suggest an upper bound on the time available prior to dissipation of the gas, and planetary models place upper limits on core sizes. Together, these constraints suggest that Jupiter and Saturn formed in 1-10 million years, and the density of solids in the region of their formation was a few times as large as the lower bound provided by the traditional minimum mass nebula.

  3. Jupiter and Its Galilean Satellites

    NASA Technical Reports Server (NTRS)

    McGrath, Melissa A.

    2012-01-01

    Jupiter is one of the two most studied planets other than Earth in our Solar System. It is the largest, fastest rotating, has the strongest magnetic field, and an incredibly diverse set of satellites, most prominent of which are the four Galilean satellites discovered in 1610. Io, Europa, Ganymede and Callisto encompass some of the most bizarre environments known in the solar system, from Io, the most volcanically active and perhaps the most inhospitable body known, to Europa, currently thought to be the most likely extraterrestrial abode for habitability, to Ganymede, which is larger than Mercury, and Callisto, which has the oldest surface known in the solar system with the widest array of crater morphologies known. One of the premier areas of scientific return in solar system research in the past 15 years, due in large part to the Galileo mission and observations by the Hubble Space Telescope, has been a remarkable increase in our knowledge about these satellites. Discoveries have been made of tenuous molecular oxygen atmospheres on Europa and Ganymede, a magnetic field and accompanying auroral emissions at the poles of Ganymede, and of ozone and sulfur dioxide embedded in the surfaces of Europa, Ganymede and Callisto. Io's unusual sulfur dioxide atmosphere, including its volcanic plumes and strong electrodynamic interaction with magnetospheric plasma, has finally been quantitatively characterized. This talk will present highlights from the recent discoveries and advances in our understanding of these fascinating objects.

  4. Hot Jupiters and cool stars

    SciTech Connect

    Villaver, Eva; Mustill, Alexander J.; Livio, Mario; Siess, Lionel

    2014-10-10

    Close-in planets are in jeopardy, as their host stars evolve off the main sequence (MS) to the subgiant and red giant phases. In this paper, we explore the influences of the stellar mass (in the range 1.5-2 M {sub ☉}), mass-loss prescription, planet mass (from Neptune up to 10 Jupiter masses), and eccentricity on the orbital evolution of planets as their parent stars evolve to become subgiants and red giants. We find that planet engulfment along the red giant branch is not very sensitive to the stellar mass or mass-loss rates adopted in the calculations, but quite sensitive to the planetary mass. The range of initial separations for planet engulfment increases with decreasing mass-loss rates or stellar masses and increasing planetary masses. Regarding the planet's orbital eccentricity, we find that as the star evolves into the red giant phase, stellar tides start to dominate over planetary tides. As a consequence, a transient population of moderately eccentric close-in Jovian planets is created that otherwise would have been expected to be absent from MS stars. We find that very eccentric and distant planets do not experience much eccentricity decay, and that planet engulfment is primarily determined by the pericenter distance and the maximum stellar radius.

  5. Temporal Variations in Jupiter's Atmosphere

    NASA Technical Reports Server (NTRS)

    Simon-Miller, Amy A.; Chanover, N. J.; Yanamandra-Fisher, P.; Hammel, H. B.; dePater, I.; Noll, K.; Wong, M.; Clarke, J.; Sanchez-Levega, A.; Orton, G. S.; Gonzaga, S.

    2009-01-01

    In recent years, Jupiter has undergone many atmospheric changes from storms turning red to global. cloud upheavals, and most recently, a cornet or asteroid impact. Yet, on top of these seemingly random changes events there are also periodic phenomena, analogous to observed Earth and Saturn atmospheric oscillations. We will present 15 years of Hubble data, from 1994 to 2009, to show how the equatorial tropospheric cloud deck and winds have varied over that time, focusing on the F953N, F41 ON and F255W filters. These filters give leverage on wind speeds plus cloud opacity, cloud height and tropospheric haze thickness, and stratospheric haze, respectively. The wind data consistently show a periodic oscillation near 7-8 S latitude. We will discuss the potential for variations with longitude and cloud height, within the calibration limits of those filters. Finally, we will discuss the role that large atmospheric events, such as the impacts in 1994 and 2009, and the global upheaval of 2007, have on temporal studies, This work was supported by a grant from the NASA Planetary Atmospheres Program. HST observational support was provided by NASA through grants from Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under contract NAS5-26555.

  6. Temporal Variations in Jupiter's Atmosphere

    NASA Technical Reports Server (NTRS)

    Simon-Miller, Amy A.; Chanover, N. J.; Yanamandra-Fisher, P.; Hammel, H. B.; dePater, I.; Noll, K.; Wong, M.; Clarke, J.; Sanchez-Levega, A.; Orton, G. S.; hide

    2009-01-01

    In recent years, Jupiter has undergone many atmospheric changes from storms turning red to global. cloud upheavals, and most recently, a cornet or asteroid impact. Yet, on top of these seemingly random changes events there are also periodic phenomena, analogous to observed Earth and Saturn atmospheric oscillations. We will present 15 years of Hubble data, from 1994 to 2009, to show how the equatorial tropospheric cloud deck and winds have varied over that time, focusing on the F953N, F41 ON and F255W filters. These filters give leverage on wind speeds plus cloud opacity, cloud height and tropospheric haze thickness, and stratospheric haze, respectively. The wind data consistently show a periodic oscillation near 7-8 S latitude. We will discuss the potential for variations with longitude and cloud height, within the calibration limits of those filters. Finally, we will discuss the role that large atmospheric events, such as the impacts in 1994 and 2009, and the global upheaval of 2007, have on temporal studies, This work was supported by a grant from the NASA Planetary Atmospheres Program. HST observational support was provided by NASA through grants from Space Telescope Science Institute, which is operated by the Association of Universities for Research in Astronomy, Inc., under contract NAS5-26555.

  7. Jupiter's radiation belts and atmosphere

    NASA Technical Reports Server (NTRS)

    De Pater, I.; Dames, H. A. C.

    1979-01-01

    Maps and stripscans of the radio emission from Jupiter were made during the Pioneer 10 flyby in December 1973 at wavelengths of 6 cm, 21 cm, and 50 cm using the Westerbork telescope in the Netherlands. With this instrument the disk of the planet was resolved at 6 and 21 cm. The pictures are averaged over 15 deg of Jovian longitude. At 21 cm the stripscans clearly show the existence of a 'hot region' in the radiation belts at a System III longitude (1965.0) of 255 + or - 10 deg. Its flux is about 9% of the total nonthermal flux, and it has a volume emissivity enhanced by a factor of about 1.6 with respect to the general radiation belts. The temperature of the thermal disk at 21 cm appears to be 290 + or - 20 K. This is likely due to a high ammonia mixing ratio in the atmosphere, a factor of 4-5 larger than the expected solar value of 0.00015.

  8. The possible contamination of Jupiter

    NASA Technical Reports Server (NTRS)

    Garcia, Joe

    1988-01-01

    The Galileo probe, though at present its future is uncertain, would, if not sterilized, represent a good chance of contaminating Jupiter. Most scientists opposed to sterilizing the probe argue that to order the probe sterilized would be the death of the project, since sterilization would entail a reconstruction of the probe, and there are not enough funds to accomplish this. These scientists, however, are ignoring a relatively simple and inexpensive alternative to the traditional heat sterilization method. The main threat of contamination comes from Galileo's exterior surfaces: the shell of the probe and its parachute. The probe innermost components would not represent a threat since the probe is sealed. In light of the fact that only the exterior of Galileo would have to be sterilized, heat would not have to be used as a method of sterilization. Instead, various gas mixtures could be sprayed entirely over the probe and its parachute, gases which would kill any and all bacteria. This idea is more thoroughly examined.

  9. Formation of Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Lissauer, Jack J.; DeVincenzi, Donald L. (Technical Monitor)

    1998-01-01

    An overview of current theories of the formation of our Solar System, with emphasis on giant planets, is presented. The most detailed models are based upon observations of planets and smaller bodies within our own Solar System and of young stars and their environments. Terrestrial planets are believed to grow via pairwise accretion until the spacing of planetary orbits becomes large enough that the configuration is stable for the age of the system. Giant planets begin their growth as do terrestrial planets, but they become massive enough that they are able to accumulate substantial amounts of gas before the protoplanetary disk dissipates. Larger disk mass allows for faster growth of solid planetary bodies. The ability of a solid planet to trap gas from the protoplanetary disk increases rapidly as its mass increases (because the depth of its gravitational potential well increases), but decreases as the planetesimal accretion rate is increased (as it becomes hotter). The net effect of increasing disk mass is that gas giant planets form more rapidly, but with larger core masses. Observations of circumstellar disks suggest an upper bound on the time available prior to dissipation of the gas, and planetary models place upper limits on core sizes. Together, these constraints suggest that Jupiter and Saturn formed in 1 - 10 million years, and the density of solids in the region of their formation was a few times as large as the lower bound provided by the traditional minimum mass nebula.

  10. RAPID FORMATION OF SATURN AFTER JUPITER COMPLETION

    SciTech Connect

    Kobayashi, Hiroshi; Ormel, Chris W.; Ida, Shigeru E-mail: ormel@astro.berkeley.edu

    2012-09-01

    We have investigated Saturn's core formation at a radial pressure maximum in a protoplanetary disk, which is created by gap opening by Jupiter. A core formed via planetesimal accretion induces the fragmentation of surrounding planetesimals, which generally inhibits further growth of the core by removal of the resulting fragments due to radial drift caused by gas drag. However, the emergence of the pressure maximum halts the drift of the fragments, while their orbital eccentricities and inclinations are efficiently damped by gas drag. As a result, the core of Saturn rapidly grows via accretion of the fragments near the pressure maximum. We have found that in the minimum-mass solar nebula, kilometer-sized planetesimals can produce a core exceeding 10 Earth masses within two million years. Since Jupiter may not have undergone significant type II inward migration, it is likely that Jupiter's formation was completed when the local disk mass has already decayed to a value comparable to or less than Jovian mass. The expected rapid growth of Saturn's core on a timescale comparable to or shorter than the observationally inferred disk lifetime enables Saturn to acquire the current amount of envelope gas before the disk gas is completely depleted. The high heat energy release rate onto the core surface due to the rapid accretion of the fragments delays onset of runaway gas accretion until the core mass becomes somewhat larger than that of Jupiter, which is consistent with the estimate based on interior modeling. Therefore, the rapid formation of Saturn induced by gap opening of Jupiter can account for the formation of multiple gas giants (Jupiter and Saturn) without significant inward migration and larger core mass of Saturn than that of Jupiter.

  11. In-Situ Dust Measurements in Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Krueger, H.; Gruen, E.; Hamilton, D. P.

    2003-04-01

    Jupiter's ring system -- the archetype of ethereal ring systems -- consists of at least three components: the main ring, the vertically extended halo and the gossamer ring(s). The small moonlets Thebe and Amalthea orbit Jupiter within the gossamer ring region and structure in the intensity obtained from imaging observations indicates that these moons are the dominant sources of the gossamer ring material. The current picture implies that particles ejected from a source moon evolve inward under the Poynting-Robertson drag. Beyond Thebe's orbit, a very faint outward extension of the gossamer ring has also been observed which is not yet explained. Typical grain radii derived from optical imaging are a few micrometers. In November 2002 the Galileo spacecraft traversed the gossamer ring for the first time and had a close flyby at Amalthea. With the in-situ dust detector on board, dust measurements were collected throughout the gossamer ring and close to Amalthea. Several hundred impacts of dust grains were recorded and the data sets (impact charges, rise times, impact directions, etc.) of about 70 impacts were transmitted to Earth. In-situ dust measurements provide information about the physical properties of the dust environment not accessible with imaging techniques. They directly provide dust spatial densities along the spacecraft trajectory as well as grain sizes and impact speeds. This allows to test and refine current models of ring particle dynamics (see D. P. Hamilton et al., this conference). In particular, the direct measurement of grain sizes and dust spatial density in different regions of the gossamer ring allow to better constrain the forces dominating the grains' dynamics. The Galileo measurements in Jupiter's gossamer ring pave the way towards the in-situ dust measurements with Cassini in Saturn's E ring beginning in 2004.

  12. Galileo in-situ dust measurements in Jupiter's Gossamer Rings

    NASA Astrophysics Data System (ADS)

    Krueger, H.; Grün, E.; Hamilton, D. P.

    2003-05-01

    Jupiter's ring system -- the archetype of ethereal ring systems -- consists of at least three components: the main ring, the vertically extended halo and the gossamer ring(s). The small moonlets Thebe and Amalthea orbit Jupiter within the gossamer ring region and structure in the intensity obtained from imaging observations indicates that these moons are the dominant sources of the gossamer ring material. The current picture implies that particles ejected from a source moon evolve inward under the Poynting-Robertson drag. Beyond Thebe's orbit, a very faint outward extension of the gossamer ring has also been observed which is not yet explained. Typical grain radii derived from optical imaging are a few micrometers. In November 2002 the Galileo spacecraft traversed the gossamer ring for the first time and had a close flyby at Amalthea. With the in-situ dust detector on board, dust measurements were collected throughout the gossamer ring and close to Amalthea. Several hundred impacts of dust grains were recorded and the data sets (impact charges, rise times, impact directions, etc.) of about 90 impacts were transmitted to Earth. In-situ dust measurements provide information about the physical properties of the dust environment not accessible with imaging techniques. They directly provide dust spatial densities along the spacecraft trajectory as well as grain sizes and impact speeds. This allows to test and refine current models of ring particle dynamics (see D. P. Hamilton et al., this conference). In particular, the direct measurement of grain sizes and dust spatial density in different regions of the gossamer ring allow to better constrain the forces dominating the grains' dynamics. The Galileo measurements in Jupiter's gossamer ring pave the way towards the in-situ dust measurements with Cassini in Saturn's E ring beginning in 2004.

  13. Evidence for Widely Distributed Ammonia Ice on Jupiter

    NASA Astrophysics Data System (ADS)

    Sromovsky, Lawrence A.; Fry, P. M.

    2009-09-01

    Analysis of near-IR VIMS spectra of Jupiter implies the existence of cloud layers with substantial 3-micron absorption. This was also inferred from ISO spectra (Brooke et al., 1998, Icarus 136, 1-13) and from NIMS spectra (Irwin et al. 2001, Icarus 149, 397-415). Brooke et al. obtained good fits at 3-microns using ammonia as the absorber, but Irwin et al. rejected ammonia because a key 2-micron feature was absent. However, we find that NICMOS center-to-limb observations of Jupiter's low latitudes (PID 10161, de Pater, PI) are difficult to explain without a cloud layer that preferentially absorbs light near 2 microns. The combined evidence of 2-micron (NICMOS) and 3-micron (VIMS) absorptions indicate that ammonia ice particles are present, not just over the tiny fraction of Jupiter where Spectrally Identifiable Ammonia Clouds (SIACs) are observed (Baines et al. 2002, Icarus 159,74-94), but widely distributed, as suggested by other modeling efforts based on ISO spectra (Brooke et al., 1998) and SIRS spectra (Wong et al., 2004, P&SS 52, 385-395). We find good fits to both NICMOS and VIMS observations with a dual middle cloud layer, the lower of which (500-750 mb) is composed of ammonia ice, and the upper of which (350-450 mb) is gray and somewhat absorbing. This upper layer serves to mask the sharpest absorption feature of ammonia at wavelengths near 3 microns, without resorting to coating by other condensibles. Although 10-micron radius ammonia particles produce distinct 2-micron absorption features that are not seen in VIMS spectra, smaller particles produce less distinctive features and appear capable of fitting both VIMS spectra and NICMOS imaging observations. The most variable layer is 150-250 mb or more deeper than the ammonia layer and possibly composed of NH4SH. This work was supported by NASA's Outer Planet Data Analysis and Cassini Data Analysis Programs.

  14. A 'Moving' Jupiter Global Map (Animation)

    NASA Technical Reports Server (NTRS)

    2007-01-01

    The Long Range Reconnaissance Imager (LORRI) on New Horizons has acquired six global maps of Jupiter as the spacecraft approaches the giant planet for a close encounter at the end of February. The high-resolution camera acquired each of six observation 'sets' as a series of individual pictures taken one hour apart, covering a full 10-hour rotation of Jupiter. The LORRI team at the Johns Hopkins University Applied Physics Laboratory (APL) reduced the sets to form six individual maps in a simple rectangular projection. These six maps were then combined to make the movie.

    The table below shows the dates and the ranges from Jupiter at which these six sets of observations were acquired. Even for the latest set of images taken January 21-22, from 60.5 million kilometers (37.6 million miles), New Horizons was still farther from Jupiter than the average distance of Mercury from the Sun. At that distance from Jupiter, a single LORRI picture resolution element amounts to 300 kilometers (186 miles) on Jupiter.

    Many features seen in Jupiter's atmosphere are giant storm clouds. The Little Red Spot, which LORRI will image close-up on February 27, is the target-like feature located near 30 degrees South and 230 degrees West; this storm is larger than the Earth. The even larger Great Red Spot is seen near 20 degrees South and 320 degrees West. The counterclockwise rotation of the clouds within the Great Red Spot can be seen. The westward drift of the Great Red Spot is easily seen in the movie, as is the slower drift, in the opposite direction, of the Little Red Spot. The storms of Jupiter are not fixed in location relative to each other or relative to any solid surface below, because Jupiter is a fluid planet without a solid surface.

    Also, dramatic changes are seen in the series of bright plume-like clouds encircling the planet between 0 and 10 degrees North. Scientists believe these result from an enormous atmospheric wave with rising air, rich in ammonia that

  15. JUPITER AS A GIANT COSMIC RAY DETECTOR

    SciTech Connect

    Rimmer, P. B.; Stark, C. R.; Helling, Ch.

    2014-06-01

    We explore the feasibility of using the atmosphere of Jupiter to detect ultra-high-energy cosmic rays (UHECRs). The large surface area of Jupiter allows us to probe cosmic rays of higher energies than previously accessible. Cosmic ray extensive air showers in Jupiter's atmosphere could in principle be detected by the Large Area Telescope (LAT) on the Fermi observatory. In order to be observed, these air showers would need to be oriented toward the Earth, and would need to occur sufficiently high in the atmosphere that the gamma rays can penetrate. We demonstrate that, under these assumptions, Jupiter provides an effective cosmic ray ''detector'' area of 3.3 × 10{sup 7} km{sup 2}. We predict that Fermi-LAT should be able to detect events of energy >10{sup 21} eV with fluence 10{sup –7} erg cm{sup –2} at a rate of about one per month. The observed number of air showers may provide an indirect measure of the flux of cosmic rays ≳ 10{sup 20} eV. Extensive air showers also produce a synchrotron signature that may be measurable by Atacama Large Millimeter/submillimeter Array (ALMA). Simultaneous observations of Jupiter with ALMA and Fermi-LAT could be used to provide broad constraints on the energies of the initiating cosmic rays.

  16. Generation of lightning in Jupiter's water cloud.

    PubMed

    Gibbard, S; Levy, E H; Lunine, J I

    1995-12-07

    Lightning is a familiar feature of storms on the Earth, and has also been seen on Jupiter and inferred indirectly to occur on Venus and Neptune. On Jupiter, lightning may be important as a source of energy to drive chemical reactions in the atmosphere, perhaps determining the abundances of molecules such as CO, HCN and C2H2. Lightning may be generated in Jupiter's water clouds by a mechanism similar to that which operates in terrestrial thunderstorms. Here we investigate the development of lightning by modelling the thunderstorm separation of electrical charge on precipitating ice particles at varying depths in Jupiter's atmosphere. We find that lightning can indeed be generated in the jovian water clouds, and that--in agreement with estimates from the analysis of Voyager images--it is most likely to occur at the 3- or 4-bar pressure level. Our model also predicts that a condensed-water abundance in the range of at least 1-2 g m-3 is required for lightning to occur in jovian thunderstorms--a prediction that may be tested when the Galileo probe arrives at Jupiter on 7 December 1995.

  17. The Icy Moons of Jupiter

    NASA Astrophysics Data System (ADS)

    Greenberg, Richard

    The Galilean satellites formed in a nebula of dust and gas that surrounded Jupiter toward the end of the formation of the giant planet itself. Their diverse initial compositions were determined by conditions in the circum-jovian nebula, just as the planets' initial properties were governed by their formation within the circum-solar nebula. The Galilean satellites subsequently evolved under the complex interplay of orbital and geophysical processes, which included the effects of orbital resonances, tides, internal differentiation, and heat. The history and character of the satellites can be inferred from consideration of the formation of planets and the satellites, from studies of their plausible orbital evolution, from measurements of geophysical properties, especially gravitational and magnetic fields, from observations of the compositions and geological structure of their surfaces, and from geophysical modeling of the processes that can relate these lines of evidence. The three satellites with large water-ice components, Europa, Ganymede, and Callisto are very different from one another as a result of the ways that these processes have played out in each case. Europa has a deep liquid-water ocean with a thin layer of surface ice, Ganymede and Callisto likely have relatively thin liquid water layers deep below their surfaces, and Callisto remains only partially differentiated, with rock and ice mixed through much of its interior. A tiny inner satellite, Amalthea, also appears to be largely composed of ice. Each of these moons is fascinating in its own right, and the ensemble provides a powerful set of constraints on the processes that led to their formation and evolution.

  18. On the Behavior of the Galilean Satellites in the Jumping Jupiter Scenario

    NASA Astrophysics Data System (ADS)

    Deienno, Rogerio; Nesvorný, D.; Yokoyama, T.

    2013-10-01

    The Nice model of the dynamical instability and migration of the giant planets can explain many properties of our present Solar System, and can be used to constrain its early architecture. In the jumping Jupiter version of the Nice model, required from the terrestrial planet constrains, Jupiter is involved in encounters with an ice giant. Here we study the survival of the Galilean satellites in the jumping Jupiter model. This is an important concern because the ice giant encounters, if deep enough, could dynamically interfere with the orbits of the Galilean satellites, and lead to implausible results. The jumping Jupiter models are taken from Nesvorný and Morbidelli 2012 (NM12). Our metodology in this study take into account the effects of the Sun, Jupiter's oblateness and obliquity, as well as the planetary close encounters tracked in NM12 upon the Galilean moons. We considered three instability cases that differed in the number and distribution of ice giant encounters with Jupiter. In each case, we considered 1000 realizations of the Galilean satellite system before the instability, and integrated the dynamical response of satellite orbits to ice giant encounters. We found that in one of the considered cases, where the number of close encounters was relatively small, the Galilean satellite orbits were not significantly disturbed. In the other two, the final orbital eccentricities were [0-0.2], and Callisto's semi-major axis ended within [22-30]Rj, while the other satellites kept their semi-major axis nearly constant. As Callisto's semi-major axis may vary as much, we also hint on the possibility that all four Galilean satellites were originally formed in a Laplace resonance, and Callisto was kicked out of it by encounters. These results: i) show that Galilean satellites are an important constrain on the planetary instability; ii) can check on the possibility to the Galilean system have been formed in a different configuration of seen today. Acknowledgement

  19. Did Jupiter's core form in the innermost parts of the Sun's protoplanetary disc?

    NASA Astrophysics Data System (ADS)

    Raymond, Sean N.; Izidoro, Andre; Bitsch, Bertram; Jacobson, Seth A.

    2016-05-01

    Jupiter's core is generally assumed to have formed beyond the snow line. Here we consider an alternative scenario that Jupiter's core may have accumulated in the innermost part of the protoplanetary disc. A growing body of research suggests that small particles (`pebbles') continually drift inward through the disc. If a fraction of drifting pebbles is trapped at the inner edge of the disc, several Earth-mass cores can quickly grow. Subsequently, the core may migrate outward beyond the snow line via planet-disc interactions. Of course, to reach the outer Solar system Jupiter's core must traverse the terrestrial planet-forming region. We use N-body simulations including synthetic forces from an underlying gaseous disc to study how the outward migration of Jupiter's core sculpts the terrestrial zone. If the outward migration is fast (τmig ˜ 104 yr), the core simply migrates past resident planetesimals and planetary embryos. However, if its migration is slower (τmig ˜ 105 yr) the core clears out solids in the inner disc by shepherding objects in mean motion resonances. In many cases, the disc interior to 0.5-1 AU is cleared of embryos and most planetesimals. By generating a mass deficit close to the Sun, the outward migration of Jupiter's core may thus explain the absence of terrestrial planets closer than Mercury. Jupiter's migrating core often stimulates the growth of another large (˜Earth-mass) core - that may provide a seed for Saturn's core - trapped in an exterior resonance. The migrating core also may transport a fraction of terrestrial planetesimals, such as the putative parent bodies of iron meteorites, to the asteroid belt.

  20. Comprehensive Optical Coverage of Jupiter for Spectral Comparison with NH4SH

    NASA Astrophysics Data System (ADS)

    Thelen, Alexander E.; Chanover, Nancy; Loeffler, Mark; Hudson, Reggie; Simon, Amy

    2015-11-01

    The distinct regions in Jupiter's atmosphere - comprised of belts, zones, storms, and the Great Red Spot - are thought to be colored by unidentified chemical compounds called chromophores. These molecules, created through Jupiter's complex atmospheric chemistry, may be responsible for the spectral slope and lack of features in the blue (shortwards of 500 nm) portion of Jupiter's optical spectrum. Though many candidate compounds have been proposed - such as ammonium hydrosulfide (NH4SH) - the identity of the coloring agent (or agents) remains elusive due to the sparse history of laboratory experiments conducted at appropriate temperatures and pressures for Jovian conditions. To build on previous ground-based observations of Jupiter in the optical, we have obtained spectra with the Dual Imaging Spectrograph - mounted on the Astrophysical Research Consortium 3.5-meter telescope at Apache Point Observatory - over a wide portion of the visible spectrum (~380-880 nm) by utilizing multiple central wavelength settings. These observations, taken during February, 2013 and April, 2015, cover multiple latitudinal regions on Jupiter, including the Great Red Spot. In this study, we present the spectral comparison of various regions in the Jovian atmosphere with data taken at the Cosmic Ice Laboratory at NASA’s Goddard Space Flight Center. By exposing thin films of NH4SH to varying amounts of ionizing radiation at Jovian temperature conditions, we can analyze the color and spectral changes of the ice. This enables us to evaluate NH4SH as a candidate chromophore through comparisons of spectral slope and features found in ground-based optical spectra of Jupiter. This work was supported by NASA’s Outer Planets Research Program through grant number NNX12AJ14G.

  1. Jupiter's global ammonia distribution inferred from Juno Microwave Radiometer Observations

    NASA Astrophysics Data System (ADS)

    Li, Cheng; Ingersoll, Andrew; Ewald, Shawn; Oyafuso, Fabiano; Janssen, Michael

    2017-04-01

    The Juno microwave radiometer (Juno/MWR) has made several observations of Jupiter's atmosphere by measuring the thermal emission from pressure levels down to a few hundred bars. The main objective of Juno/MWR is to determine Jupiter's deep water abundance because water is the key to understand Jovian meteorology that we observe at the cloud level, and because the deep water abundance hints at a giant planet's volatile and heavy element history. Since ammonia is the major opacity source in the Juno/MWR channels, it is especially important to figure out the ammonia distribution before we can conclude anything on the water abundance. At this stage of our analysis, we have inverted a global map (vertical and latitudinal) of ammonia distribution from the observed brightness temperatures at six wavelengths using the Markov Chain Monte Carlo technique. This method fully calibrates error and explores a wide range of the parameter space to avoid falling into a local minimum. The robustness of the retrieval is explained by matching the features in the ammonia distribution with the features in the microwave spectra. We will also announce the initial result of the retrieval of water abundance using the same technique.

  2. Heating of Jupiter's upper atmosphere above the Great Red Spot

    NASA Astrophysics Data System (ADS)

    O'Donoghue, James; Moore, Luke; Stallard, Tom; Melin, Henrik

    2016-10-01

    Measured upper-atmospheric, mid-to-low latitude temperatures of the giant planets are hundreds of degrees warmer than simulations based on solar heating alone can explain. Modelling studies, focused on additional sources of heating, have been so far unable to resolve this significant model-data discrepancy. Equatorward transport of energy from the hot auroral regions was expected to heat low latitude regions; instead, models have demonstrated that auroral energy is trapped at high latitudes, a consequence of the strong Coriolis forces on these rapidly rotating planets. Wave heating, driven from below, represents another potential source of upper-atmospheric heating. Using data taken in 2012 by the ground-based NASA IRTF, we found through observations of the H3+ ion that the upper atmosphere above Jupiter's Great Red Spot (GRS) - the largest storm in the solar system - is hundreds of degrees hotter than anywhere else on the planet. Specifically, the result shows that the northern region of the spot was over 1600 K, and that background temperatures away from the spot are ~850 K. The hotspot, by process of elimination, must be heated from below, and this detection is therefore strong evidence for coupling between Jupiter's lower and upper atmospheres, likely the result of upward propagating acoustic and/or gravity waves. Our results indicate that the lower atmosphere may yet play an important role in resolving the giant planet 'energy crisis'.

  3. On the abundance of non-cometary HCN on Jupiter.

    PubMed

    Moses, Julianne I; Visscher, Channon; Keane, Thomas C; Sperier, Aubrey

    2010-01-01

    Using one-dimensional thermochemical/photochemical kinetics and transport models, we examine the chemistry of nitrogen-bearing species in the Jovian troposphere in an attempt to explain the low observational upper limit for HCN. We track the dominant mechanisms for interconversion of N2-NH3 and HCN-NH3 in the deep, high-temperature troposphere and predict the rate-limiting step for the quenching of HCN at cooler tropospheric altitudes. Consistent with some other investigations that were based solely on time-scale arguments, our models suggest that transport-induced quenching of thermochemically derived HCN leads to very small predicted mole fractions of hydrogen cyanide in Jupiter's upper troposphere. By the same token, photochemical production of HCN is ineffective in Jupiter's troposphere: CH4-NH3 coupling is inhibited by the physical separation of the CH4 photolysis region in the upper stratosphere from the NH3 photolysis and condensation region in the troposphere, and C2H2-NH3 coupling is inhibited by the low tropospheric abundance of C2H2. The upper limits from infrared and submillimetre observations can be used to place constraints on the production of HCN and other species from lightning and thundershock sources.

  4. Simulation of What Juno Will 'See' From Jupiter Orbit

    NASA Image and Video Library

    This animation shows how Jupiter will appear to the camera onboard NASA's Juno mission, called JunoCam, as the spacecraft goes through an orbit. Juno will circle Jupiter every 11 days from an ellip...

  5. The origin of long-lived asteroids in the 2:1 mean-motion resonance with Jupiter

    NASA Astrophysics Data System (ADS)

    Chrenko, O.; Brož, M.; Nesvorný, D.; Tsiganis, K.; Skoulidou, D. K.

    2015-08-01

    The 2:1 mean-motion resonance with Jupiter harbours two distinct groups of asteroids. The short-lived population is known to be a transient group sustained in steady state by the Yarkovsky semimajor axis drift. The long-lived asteroids, however, can exhibit dynamical lifetimes comparable to 4 Gyr. They reside near two isolated islands of the phase space denoted A and B, with an uneven population ratio B/A ≃ 10. The orbits of A-island asteroids are predominantly highly inclined, compared to island B. The size-frequency distribution is steep but the orbital distribution lacks any evidence of a collisional cluster. These observational constraints are somewhat puzzling and therefore the origin of the long-lived asteroids has not been explained so far. With the aim to provide a viable explanation, we first update the resonant population and revisit its physical properties. Using an N-body model with seven planets and the Yarkovsky effect included, we demonstrate that the dynamical depletion of island A is faster, in comparison with island B. Then we investigate (i) the survivability of primordial resonant asteroids and (ii) capture of the population during planetary migration, following a recently described scenario with an escaping fifth giant planet and a jumping-Jupiter instability. We also model the collisional evolution of the resonant population over past 4 Gyr. Our conclusion is that the long-lived group was created by resonant capture from a narrow part of hypothetical outer main-belt family during planetary migration. Primordial asteroids surviving the migration were probably not numerous enough to substantially contribute to the observed population.

  6. Dayside-Nightside Temperature Differences in Hot Jupiter Atmospheres

    NASA Astrophysics Data System (ADS)

    Komacek, Thaddeus D.; Showman, Adam P.

    2015-12-01

    The infrared phase curves of low-eccentricity transiting hot Jupiters show a trend of increasing flux amplitude, or increasing day-night temperature difference, with increasing equilibrium temperature. Here we utilize atmospheric circulation modeling and analytic theory to understand this trend, and the more general question: what processes control heat redistribution in tidally-locked giant planet atmospheres? We performed a wide range of 3D numerical simulations of the atmospheric circulation with simplified forcing, and constructed an analytic theory that explains the day-night temperature differences in these simulations over a wide parameter space. Our analytic theory shows that day-night temperature differences in tidally-locked planet atmospheres are mediated by wave propagation. If planetary-scale waves are free to propagate longitudinally, they will efficiently flatten isentropes and lessen day-night temperature differences. If these waves are damped, the day-night temperature differences will necessarily be larger. We expect that wave propagation in hot Jupiter atmospheres can be damped in two ways: by either radiative cooling or frictional drag. Both of these processes increase in efficacy with increasing equilibrium temperature, as radiative cooling is directly related to the cube of temperature and magnetically-induced (Lorentz) drag becomes stronger with increasing partial ionization and hence temperature. We find that radiative cooling plays the largest role in damping wave propagation and hence plays the biggest role in controlling day-night temperature differences. As a result, day-night temperature differences in hot Jupiter atmospheres decrease with increasing pressure and increase with increasing stellar flux. One can apply this result to phase curve observations of individual hot Jupiters in multiple bandpasses, as varying flux amplitudes between wavelengths implies that different photospheric pressure levels are being probed. Namely, a larger

  7. Jupiter White Ovals/True and False Color

    NASA Image and Video Library

    1998-03-26

    Oval cloud systems of this type are often associated with chaotic cyclonic systems such as the balloon-shaped vortex seen here between the well-formed ovals. This system is centered near 30 degrees south latitude relative to the center of the planet and 100 degrees west longitude, and rotates in a clockwise direction about its center. The oval shaped vortices in the upper half of the mosaic are two of the three long-lived white ovals that formed to the south of the Great Red Spot in the 1930's and, like the Great Red Spot, rotate in a counterclockwise sense. The east-to-west dimension of the left-most white oval is 9,000 kilometers (5,592 miles) across. For comparison, the diameter of Earth is 12,756 kilometers, or 7,928 miles. The white ovals drift in longitude relative to one another and are presently restricting the cyclonic structure. To the south, the smaller oval and its accompanying cyclonic system are moving eastward at about 0.4 degrees per day relative to the larger ovals. The interaction between these two cyclonic storm systems is producing high, thick cumulus-like clouds in the southern part of the more northerly trapped system. The top mosaic combines the violet (410 nanometers) and near infrared continuum (756 nanometers) filter images to create a mosaic similar to how Jupiter would appear to human eyes. Differences in coloration are due to the composition and abundance of trace chemicals in Jupiter's atmosphere. The lower mosaic uses the Galileo imaging camera's three near-infrared wavelengths (756 nanometers, 727 nanometers, and 889 nanometers displayed in red, green, and blue) to show variations in cloud height and thickness. Light blue clouds are high and thin, reddish clouds are deep, and white clouds are high and thick. The clouds and haze over the white ovals are high, extending into Jupiter's stratosphere. There is a lack of high haze over the cyclonic feature. Dark purple most likely represents a high haze overlying a clear deep atmosphere

  8. Principal components analysis of Jupiter VIMS spectra

    USGS Publications Warehouse

    Bellucci, G.; Formisano, V.; D'Aversa, E.; Brown, R.H.; Baines, K.H.; Bibring, J.-P.; Buratti, B.J.; Capaccioni, F.; Cerroni, P.; Clark, R.N.; Coradini, A.; Cruikshank, D.P.; Drossart, P.; Jaumann, R.; Langevin, Y.; Matson, D.L.; McCord, T.B.; Mennella, V.; Nelson, R.M.; Nicholson, P.D.; Sicardy, B.; Sotin, Christophe; Chamberlain, M.C.; Hansen, G.; Hibbits, K.; Showalter, M.; Filacchione, G.

    2004-01-01

    During Cassini - Jupiter flyby occurred in December 2000, Visual-Infrared mapping spectrometer (VIMS) instrument took several image cubes of Jupiter at different phase angles and distances. We have analysed the spectral images acquired by the VIMS visual channel by means of a principal component analysis technique (PCA). The original data set consists of 96 spectral images in the 0.35-1.05 ??m wavelength range. The product of the analysis are new PC bands, which contain all the spectral variance of the original data. These new components have been used to produce a map of Jupiter made of seven coherent spectral classes. The map confirms previously published work done on the Great Red Spot by using NIMS data. Some other new findings, presently under investigation, are presented. ?? 2004 Published by Elsevier Ltd on behalf of COSPAR.

  9. Atmospheric Motion in Jupiter Northern Hemisphere

    NASA Image and Video Library

    2000-09-25

    True-color (left) and false-color (right) mosaics of Jupiter's northern hemisphere between 10 and 50 degrees latitude. Jupiter's atmospheric motions are controlled by alternating eastward and westward bands of air between Jupiter's equator and polar regions. The direction and speed of these bands influences the color and texture of the clouds seen in this mosaic. The high and thin clouds are represented by light blue, deep clouds are reddish, and high and thick clouds are white. A high haze overlying a clear, deep atmosphere is represented by dark purple. This image was taken by NASA's Galileo spacecraft on April 3, 1997 at a distance of 1.4 million kilometers (.86 million miles). http://photojournal.jpl.nasa.gov/catalog/PIA03000

  10. Jupiter Pearl and Swirling Cloud Tops

    NASA Image and Video Library

    2017-01-19

    This amateur-processed image was taken on Dec. 11, 2016, at 9:27 a.m. PST (12:27 p.m. EST), as NASA's Juno spacecraft performed its third close flyby of Jupiter. At the time the image was taken, the spacecraft was about 15,200 miles (24,400 kilometers) from the gas giant planet. The citizen scientist (Eric Jorgensen) cropped the JunoCam image and enhanced the color to draw attention to Jupiter's swirling clouds southeast of the "pearl." The "pearl" is one of eight massive rotating storms at 40 degrees south latitude on Jupiter, known colloquially as the "string of pearls." The processing of this image highlights the turbulence of the clouds in the south temperate belt of the planet. http://photojournal.jpl.nasa.gov/catalog/PIA21377

  11. Atmospheric Motion in Jupiter's Northern Hemisphere

    NASA Technical Reports Server (NTRS)

    2000-01-01

    True-color (left) and false-color (right) mosaics of Jupiter's northern hemisphere between 10 and 50 degrees latitude. Jupiter's atmospheric motions are controlled by alternating eastward and westward bands of air between Jupiter's equator and polar regions. The direction and speed of these bands influences the color and texture of the clouds seen in this mosaic. The high and thin clouds are represented by light blue, deep clouds are reddish, and high and thick clouds are white. A high haze overlying a clear, deep atmosphere is represented by dark purple. This image was taken by NASA's Galileo spacecraft on April 3, 1997 at a distance of 1.4 million kilometers (.86 million miles).

  12. Cassini First-Look Images of Jupiter

    NASA Image and Video Library

    2000-10-05

    This image of Jupiter was taken by the Cassini Imaging Science narrow angle camera through the blue filter (centered at 445 nanometers) on October 1, 2000, 15:26 UTC at a distance of 84.1million km from Jupiter. The smallest features that can be seen are 500 kilometers across. The contrast between bright and dark features in this region of the spectrum is determined by the different light absorbing properties of the particles composing Jupiter's clouds. Ammonia ice particles are white, reflecting all light that falls on them. But some particles are red, and absorb mostly blue light. The composition of these red particles and the processes which determine their distribution are two of the long-standing mysteries of Jovian meteorology and chemistry. Note that the Great Red Spot contains a dark core of absorbing particles. http://photojournal.jpl.nasa.gov/catalog/PIA02666

  13. Radiative-dynamical equilibrium states for Jupiter

    NASA Technical Reports Server (NTRS)

    Trafton, L. M.; Stone, P. H.

    1974-01-01

    In order to obtain accurate estimates of the radiative heating that drives motions in Jupiter's atmosphere, previous radiative equilibrium calculations are improved by including the NH3 opacities and updated results for the pressure-induced opacities. These additions increase the radiative lapse rate near the top of the statically unstable region and lead to a fairly constant radiative lapse rate below the tropopause. The radiative-convective equilibrium temperature structure consistent with these changes is calculated, but it differs only slightly from earlier calculations. The radiative equilibrium calculations are used to calculate whether equilibrium states can occur on Jupiter which are similar to the baroclinic instability regimes on the earth and Mars. The results show that Jupiter's dynamical regime cannot be of this kind, except possibly at very high latitudes, and that its regime must be a basically less stable one than this kind.

  14. Juno Captures Jupiter Glow in Infrared Light

    NASA Image and Video Library

    2016-09-02

    As NASA's Juno spacecraft approached Jupiter on Aug. 27, 2016, the Jovian Infrared Auroral Mapper (JIRAM) instrument captured the planet's glow in infrared light. The video is composed of 580 images collected over a period of about nine hours while Jupiter completed nearly a full rotation on its axis. The video shows the two parts composing the JIRAM imager: the lower one, in a red color scale, is used for mapping the planet's thermal emission at wavelengths around 4.8 microns; the upper one, in a blue color scale, is used to map the auroras at wavelengths around 3.45 microns. In this case the exposure time of the imager was optimized to observe the planet's thermal emission. However, it is possible to see a faint aurora and Jupiter's moon Io approaching the planet. The Great Red Spot is also visible just south of the planet's equator. A movie is available at http://photojournal.jpl.nasa.gov/catalog/PIA21036

  15. The 1981 Jupiter Orbiter Probe mission

    NASA Technical Reports Server (NTRS)

    Moore, J. W.; Hyde, J. R.; Van Allen, J. A.; Nunamaker, R. S.

    1976-01-01

    Plans for the 1981 Jupiter Orbiter Probe (JOP) mission are presented in some detail. The need for a Jupiter entry probe, remote sensing of the planet, and an orbiter, in addition to flybys, is made clear. Launch hardware, using the Space Shuttle flight system and Interim Upper Stage, is described, along with scientific tasks laid out for the entry probe and the orbiter. Combined analysis of the Jovian magnetosphere and other orbiter missions calls for a two-part orbiter with one part spun and the other de-spun. Related design problems and solutions are described and diagrammed. Jovian moon flybys and orbiter path adjustments by subsequent earth-launched flybys are discussed. The importance of Jupiter data for solar system evolution and possible analysis of early stages of stellar evolution or of a binary system are also treated.

  16. Atmospheric Motion in Jupiter's Northern Hemisphere

    NASA Technical Reports Server (NTRS)

    2000-01-01

    True-color (left) and false-color (right) mosaics of Jupiter's northern hemisphere between 10 and 50 degrees latitude. Jupiter's atmospheric motions are controlled by alternating eastward and westward bands of air between Jupiter's equator and polar regions. The direction and speed of these bands influences the color and texture of the clouds seen in this mosaic. The high and thin clouds are represented by light blue, deep clouds are reddish, and high and thick clouds are white. A high haze overlying a clear, deep atmosphere is represented by dark purple. This image was taken by NASA's Galileo spacecraft on April 3, 1997 at a distance of 1.4 million kilometers (.86 million miles).

  17. Closing in on Jupiter North Pole

    NASA Image and Video Library

    2016-09-02

    As NASA's Juno spacecraft closed in on Jupiter for its Aug. 27, 2016 pass, its view grew sharper and fine details in the north polar region became increasingly visible. The JunoCam instrument obtained this view on August 27, about two hours before closest approach, when the spacecraft was 120,000 miles (195,000 kilometers) away from the giant planet (i.e., for Jupiter's center). Unlike the equatorial region's familiar structure of belts and zones, the poles are mottled with rotating storms of various sizes, similar to giant versions of terrestrial hurricanes. Jupiter's poles have not been seen from this perspective since the Pioneer 11 spacecraft flew by the planet in 1974. http://photojournal.jpl.nasa.gov/catalog/PIA21030

  18. Detection and analysis of Jupiter's decametric micropulses

    NASA Technical Reports Server (NTRS)

    Lebo, G. R.

    1972-01-01

    The occurrence of Jupiter's decametric radio emission can be correlated with the central meridian longitude of Jupiter as if the active regions were radio transmitters placed at fixed longitudes on its surface. These active regions are commonly called sources and are labelled Source A, Jovian longitude = 200 deg, Source B = 100 deg and Source C =300 deg. These sources are not always active. However, they can be turned-on if Jupiter's innermost Galilean moon, Io, is in the right phase. In fact, if Io is found 90 deg from superior geocentric conjunction (maximum eastern elongation) and if source B is simultaneously on the central meridian, source B radiation is almost guaranteed, whereas source C radiation is highly likely when Io is found 240 deg from superior geocentric conjunction. Source A radiation is largely independent of Io's position. Interestingly, the Io-related radio storms contain unusually rapid events that can only be properly studied using wide-band techniques.

  19. Jupiter in True and False Color

    NASA Image and Video Library

    2001-01-23

    These color composite frames of the mid-section of Jupiter were of narrow angle images acquired on December 31, 2000, a day after Cassini's closest approach to the planet. The smallest features in these frames are roughly ~ 60 kilometers. The left is natural color, composited to yield the color that Jupiter would have if seen by the naked eye. The right frame is composed of 3 images: two were taken through narrow band filters centered on regions of the spectrum where the gaseous methane in Jupiter's atmosphere absorbs light, and the third was taken in a red continuum region of the spectrum, where Jupiter has no absorptions. The combination yields an image whose colors denote the height of the clouds. Red regions are deep water clouds, bright blue regions are high haze (like the blue covering the Great Red Spot). Small, intensely bright white spots are energetic lightning storms which have penetrated high into the atmosphere where there is no opportunity for absorption of light: these high cloud systems reflect all light equally. The darkest blue regions -- for example, the long linear regions which border the northern part of the equatorial zone, are the very deep "hot spots', seen in earlier images, from which Jovian thermal emission is free to escape to space. This is the first time that global images of Jupiter in all the methane and attendant continuum filters have been acquired by a spacecraft. From images like these, the stratigraphy of Jupiter's dynamic atmosphere will be determined. http://photojournal.jpl.nasa.gov/catalog/PIA02877

  20. Jupiter Atmospheric Science in the Next Decade

    NASA Astrophysics Data System (ADS)

    Fletcher, Leigh N.; Orton, G.; Stallard, T.; Baines, K.; Sayanagi, K. M.; Martin-Torres, F. J.; Hofstadter, M.; de Pater, I.; Edgington, S.; Morales-Juberias, R.; Livengood, T.; Huestis, D.; Marty, B.; Hartogh, P.; Atkinson, D.; Moses, J.

    2009-09-01

    The exploration of Jupiter has played a pivotal role in the development of our understanding of the history of our solar system; it has served as a paradigm for the interpretation of exoplanetary systems around other stars, and as a fundamental laboratory for the myriad of physiochemical phenomena evident on the gas giants. Yet, despite great successes in the studies of Jupiter over four centuries of research, our characterisation of Jupiter remains incomplete. Jupiter's atmosphere is distinguished from Saturn's and the Ice Giants by its larger mass, dynamic "weather layer", multiple long-lived vortices and the smaller significance of seasonal variability. We review the scientific goals for Jovian exploration in the coming decade: 1. The bulk composition (e.g. heavy elements, isotopes), cooling history and internal structure (the existence of a core) of Jupiter as signatures of planetary formation and evolutionary models, along with comparisons to the other gas giants. 2. The development of a global three-dimensional understanding of the structure, meteorology and chemistry of the troposphere, stratosphere and mesosphere; the mechanisms for transport of energy, momentum and chemical species (tracers) vertically and horizontally, and the role of moist convection. 3. The coupling of the deep motions within the interior to the dynamical manifestations observed in the visible cloud layers. 4. Interactions between the lower neutral atmosphere and the upper atmosphere (thermosphere, ionosphere, magnetosphere), along with energy sources and redistribution responsible for aurora, radiolytic chemistry and high thermospheric temperatures. 5. Time-variable phenomena over a range of timescales to determine the underlying mechanisms and significance of the evolution of discrete atmospheric features, quasi-periodic global upheavals, energetic particle precipitation, asteroidal/cometary impacts and wave activity. These themes for Jupiter science will reveal the connections

  1. Lucy: Navigating a Jupiter Trojan Tour

    NASA Technical Reports Server (NTRS)

    Stanbridge, Dale; Williams, Ken; Williams, Bobby; Jackman, Coralie; Weaver, Hal; Berry, Kevin; Sutter, Brian; Englander, Jacob

    2017-01-01

    In January 2017, NASA selected the Lucy mission to explore six Jupiter Trojan asteroids. These six bodies, remnants of the primordial material that formed the outer planets, were captured in the Sun-Jupiter L4 and L5 Lagrangian regions early in the solar system formation. These particular bodies were chosen because of their diverse spectral properties and the chance to observe up close for the first time two orbiting approximately equal mass binaries, Patroclus and Menoetius. KinetX, Inc. is the primary navigation supplier for the Lucy mission. This paper describes preliminary navigation analyses of the approach phase for each Trojan encounter.

  2. Jupiter's Great Red Spot (Enhanced Color)

    NASA Image and Video Library

    2017-07-12

    This enhanced-color image of Jupiter's Great Red Spot was created by citizen scientist Jason Major using data from the JunoCam imager on NASA's Juno spacecraft. The image was taken on July 10, 2017 at 07:10 p.m. PDT (10:10 p.m. EDT), as the Juno spacecraft performed its 7th close flyby of Jupiter. At the time the image was taken, the spacecraft was about 8,648 miles (13,917 kilometers) from the tops of the clouds of the planet. https://photojournal.jpl.nasa.gov/catalog/PIA21772

  3. EVOLUTION OF OHMICALLY HEATED HOT JUPITERS

    SciTech Connect

    Batygin, Konstantin; Stevenson, David J.; Bodenheimer, Peter H.

    2011-09-01

    We present calculations of thermal evolution of hot Jupiters with various masses and effective temperatures under ohmic dissipation. The resulting evolutionary sequences show a clear tendency toward inflated radii for effective temperatures that give rise to significant ionization of alkali metals in the atmosphere, compatible with the trend of the data. The degree of inflation shows that ohmic dissipation along with the likely variability in heavy element content can account for all of the currently detected radius anomalies. Furthermore, we find that in the absence of a massive core, low-mass hot Jupiters can overflow their Roche lobes and evaporate on Gyr timescales, possibly leaving behind small rocky cores.

  4. Thermal tides on a hot Jupiter

    NASA Astrophysics Data System (ADS)

    Gu, P.-G.; Hsieh, H.-F.

    2011-07-01

    Following the linear analysis laid out by Gu & Ogilvie 2009 (hereafter GO09), we investigate the dynamical response of a non-synchronized hot Jupiter to stellar irradiation. Besides the internal and Rossby waves considered by GO09, we study the Kelvin waves excited by the diurnal Fourier harmonic of the prograde stellar irradiation. We also present a 2-dimensional plot of internal waves excited by the semi-diurnal component of the stellar irradiation and postulate that thermal bulges may arise in a hot Jupiter. Whether our postulation is valid and is consistent with the recent results from Arras & Socrates (2009b) requires further investigation.

  5. Future planetary probes for Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Butts, A. J.; Murphy, J. P.

    1979-01-01

    The paper describes a study conducted to identify the technology developments that would allow deep atmospheric investigations of Jupiter and Saturn to proceed beyond currently planned investigation of the upper atmosphere. The study considered a deep probe mission that would provide the capability to scientifically examine planetary atmospheres to the 1000-bar level and 1400-K level. The major conclusions of the study are that (1) a probe designed for Jupiter can be used with minor changes for Saturn, (2) new science instrument technology developments are required, and (3) the only new technology developments required in the engineering subsystem are high pressure thermal insulation materials and advanced data processing techniques.

  6. Radiation belts of jupiter: a second look.

    PubMed

    Fillius, R W; McIlwain, C E; Mogro-Campero, A

    1975-05-02

    The outbound leg of the Pioneer 11 Jupiter flyby explored a region farther from the equator than that traversed by Pioneer 10, and the new data require modification or augmentation of the magnetodisk model based on the Pioneer 10 flyby. The inner moons of Jupiter are sinks of energetic particles and sometimes sources. A large spike of particles was found near lo. Multiple peaks occurred in the particle fluxes near closest approach to the planet; this structure may be accounted for by a complex magnetic field configuration. The decrease in proton flux observed near minimum altitude on the Pioneer 10 flyby appears attributable to particle absorption by Amalthea.

  7. Jupiter's radiation belts - Can Pioneer 10 survive

    NASA Technical Reports Server (NTRS)

    Hess, W. N.; Birmingham, T. J.; Mead, G. D.

    1973-01-01

    Recent calculations suggest that three of the Galilean satellites are very effective in limiting the fluxes of energetic electrons and protons diffusing inward from Jupiter's outer magnetosphere. Electron and proton densities with and without lunar effects are plotted as functions of the distance from the center of the planet in units of Jupiter radii. Both electrons and protons in the model come from the solar wind. The trajectory of Pioneer 10 in magnetic coordinates is examined and the period of greatest danger to the spacecraft is discussed.

  8. HUBBLE PROVIDES COMPLETE VIEW OF JUPITER'S AURORAS

    NASA Technical Reports Server (NTRS)

    2002-01-01

    NASA's Hubble Space Telescope has captured a complete view of Jupiter's northern and southern auroras. Images taken in ultraviolet light by the Space Telescope Imaging Spectrograph (STIS) show both auroras, the oval- shaped objects in the inset photos. While the Hubble telescope has obtained images of Jupiter's northern and southern lights since 1990, the new STIS instrument is 10 times more sensitive than earlier cameras. This allows for short exposures, reducing the blurring of the image caused by Jupiter's rotation and providing two to five times higher resolution than earlier cameras. The resolution in these images is sufficient to show the 'curtain' of auroral light extending several hundred miles above Jupiter's limb (edge). Images of Earth's auroral curtains, taken from the space shuttle, have a similar appearance. Jupiter's auroral images are superimposed on a Wide Field and Planetary Camera 2 image of the entire planet. The auroras are brilliant curtains of light in Jupiter's upper atmosphere. Jovian auroral storms, like Earth's, develop when electrically charged particles trapped in the magnetic field surrounding the planet spiral inward at high energies toward the north and south magnetic poles. When these particles hit the upper atmosphere, they excite atoms and molecules there, causing them to glow (the same process acting in street lights). The electrons that strike Earth's atmosphere come from the sun, and the auroral lights remain concentrated above the night sky in response to the 'solar wind,' as Earth rotates underneath. Earth's auroras exhibit storms that extend to lower latitudes in response to solar activity, which can be easily seen from the northern U. S. But Jupiter's auroras are caused by particles spewed out by volcanoes on Io, one of Jupiter's moons. These charged particles are then magnetically trapped and begin to rotate with Jupiter, producing ovals of auroral light centered on Jupiter's magnetic poles in both the day and night skies

  9. Jupiter after Pioneer - A progress report

    NASA Technical Reports Server (NTRS)

    Mcdonough, T. R.

    1974-01-01

    In December 1973, Pioneer 10 became the first spacecraft to reach the vicinity of Jupiter. The spacecraft passed through the Jovian magnetosphere in two weeks and sent back more than 300 pictures of the big planet. Measurements were conducted of EM fields, energetic particles, and micrometeoroids. Radio occultations observed are discussed along with observations in the infrared and ultraviolet range, magnetic measurements, questions of trajectory analysis, and data obtained with the aid of a plasma analyzer. Pioneer 10 has confirmed as inescapable the fact that Jupiter radiates more energy than it receives from the sun.

  10. Obliquity Tides in Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Peale, S. J.

    two papers have pointed out that this is not so (Levrard et al. 2007; Fabrycky et al. 2007). The rotation continues to decrease below the synchronous value with increasing obliquity. As is perhaps expected, state 2 becomes unstable as the planet slows. The planet then rapidly evolves to Cassini state 1 with a negligibly small obliquity, and all isolated hot Jupiters will evolve to nearly circular orbits with their spin axes nearly normal to their orbit planes. Obliquity tides cannot be invoked as a means of additional heating of hot gaseous planets.

  11. Extreme Environments Technologies for Probes to Venus and Jupiter

    NASA Technical Reports Server (NTRS)

    Balint, Tibor S.; Kolawa, Elizabeth A.; Peterson, Craig E.; Cutts, James A.; Belz, Andrea P.

    2007-01-01

    This viewgraph presentation reviews the technologies that are used to mitigate extreme environments for probes at Venus and Jupiter. The contents include: 1) Extreme environments at Venus and Jupiter; 2) In-situ missions to Venus and Jupiter (past/present/future); and 3) Approaches to mitigate conditions of extreme environments for probes with systems architectures and technologies.

  12. Jupiter: Giant of the solar system. [its solar orbits

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Jupiter, its relationship to the other planets in the solar system, its twelve natural satellites, solar orbit and the appearance of Jupiter in the sky, and the sightings and motions of Jupiter in 1973 are discussed. Educational study projects for students are also included.

  13. Spatial distribution of water in the stratosphere of Jupiter from observations with the Herschel space observatory

    NASA Astrophysics Data System (ADS)

    Cavalié, T.; Feuchtgruber, H.; Lellouch, E.; de Val-Borro, M.; Jarchow, C.; Moreno, R.; Hartogh, P.; Orton, G.; Greathouse, T. K.; Billebaud, F.; Dobrijevic, M.; Lara, L. M.; Gonzalez, A.; Sagawa, H.

    2013-09-01

    Water in the atmospheres of the outer planets has both an internal and an external source (e.g., [1] and [2] for Jupiter). These sources are separated by a condensation layer, the tropopause cold trap, which acts as a transport barrier between the troposphere and the stratosphere. Thus, the water vapor observed by the Infrared Space Observatory (ISO) in the stratosphere of the giant planets has an external origin [3]. This external supply of water may have several sources: (i) a permanent flux from interplanetary dust particles produced from asteroid collisions and from comet activity [4], (ii) local sources from planetary environments (rings, satellites) [5], (iii) cometary "Shoemaker-Levy 9 (SL9) type" impacts [6]. In the past 15 years, several studies suggested that water in the stratosphere of Jupiter originated from the SL9 comet impacts in July 1994, but a direct proof was missing. We will report the first high S/N spatially resolved mapping observations of water in Jupiter's stratosphere carried out with the Heterodyne Instrument for the Far Infrared (HIFI) [7] and Photodetector Array Camera and Spectrometer (PACS) [8] instruments onboard the ESA Herschel Space Observatory [9]. These observations have been obtained in the framework of the Guaranteed Time Key Program "Water and related chemistry in the Solar System", also known as "Herschel Solar System Observations" (HssO) [10]. In parallel, we have monitored Jupiter's stratospheric temperature with the NASA Infrared Telescope Facility (IRTF) to separate temperature from water variability. We will present the results recently published by our team [11]. Water is found to be restricted to pressures lower than 2mbar. Its column density decreases by a factor of 2-3 between southern and northern latitudes (see Fig. 1), consistently between the HIFI and the PACS 66.4μm maps. Latitudinal temperature variability cannot explain the global north-south asymmetry in the water maps. From the latitudinal and vertical

  14. Photochemistry of Methane in Model Atmospheres of Jupiter and Titan

    NASA Technical Reports Server (NTRS)

    Bersohn, Richard

    2000-01-01

    The two central findings were 1) hydrogen atoms and hydrogen molecules photodissociated from methane are relatively richer in H than in D in other words deuterium atoms have a greater probability of remaining attached to the carbon atom. Titan, a moon of Saturn has an atmosphere which is largely nitrogen but also contains about 3% methane as well as smaller amounts of C2 and C3 hydrocarbons. If all these hydrocarbons are of biological origin, the isotopic scrambling occurring in living organisms would result in equal D atom abundances. On the other hand, if the higher hydrocarbons are derived from methane by photodissociation of methane, they should be richer in D than methane. Precise values for the enrichment were derived from our photochemical data. 2) When methane is dissociated by vuv light, methylene is produced in a singlet state. This explains why the higher hydrocarbons are sparse on Jupiter but relatively rich on Titan.

  15. Hot Jupiters from Coplanar High-eccentricity Migration

    NASA Astrophysics Data System (ADS)

    Petrovich, Cristobal

    2014-11-01

    The question of what mechanism is responsible for delivering giant planets into short-periods orbits (<10 days), the so-called hot Jupiters (HJs), is one of the fundamental unresolved questions in planet formation. In this talk, I propose that most HJs are formed through the secular interaction of two planets in eccentric and nearly coplanar orbits and tidal dissipation due to the host star, mechanism which I term coplanar high-eccentricity migration (CHEM). I will show that the HJs formed by CHEM can well-reproduce the observed period distribution, as well as explain why most HJs have low stellar obliquities. I further provide with testable predictions regarding the properties (e.g., masses and orbital periods) of the outer perturber and formation timescales in HJ systems.

  16. Ammonium Hydrosulfide and Jupiter's Great Red Spot

    NASA Astrophysics Data System (ADS)

    Loeffler, M. J.; Hudson, R.; Chanover, N.; Simon, A. A.

    2014-12-01

    The color and composition of Jupiter's Great Red Spot (GRS) has been debated for more than a century. While there are numerous hypotheses for the origin of Jupiter's GRS, recent work suggests that the GRS's color could originate from multiple components (Carlson et al., 2012; Simon et al., submitted). In light of this, we have recently begun conducting in situ laboratory experiments that test whether ammonium hydrosulfide, NH4SH, or its radiation decomposition products contribute to the GRS spectrum. In this presentation, we will discuss some of our most recent results, where we have studied the stability of NH4SH samples as a function of temperature using infrared and mass spectrometry. Funding for this work has been provided by NASA's Planetary Atmospheres and Outer Planets Research programs. ReferencesCarlson, R. W., K. H. Baines, M. S. Anderson, G. Filacchione. Chromophores from photolyzed ammonia reacting with acetylene: Application to Jupiter's Great Red Spot, DPS, 44, 2012. Simon, A. A., J. Legarreta, F. Sanz-Requena, S. Perez-Hoyos, E. Garcia-Melendo, R. W. Carlson. Spectral Comparison and Stability of Red Regions on Jupiter. J. Geophys. Res. - Planets, submitted.

  17. Jupiter Quest: A Path to Scientific Discovery.

    ERIC Educational Resources Information Center

    Bollman, Kelly A.; Rodgers, Mark H.; Mauller, Robert L.

    2001-01-01

    To experience the world of professional science, students must have access to the scientific community and be allowed to become real scientists. A partnership involving the National Aeronautics and Space Administration, the Jet Propulsion Laboratory, and the Lewis Center for Educational Research has produced Jupiter Quest, an engaging curriculum…

  18. JUPITER PROJECT - MERGING INVERSE PROBLEM FORMULATION TECHNOLOGIES

    EPA Science Inventory

    The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project seeks to enhance and build on the technology and momentum behind two of the most popular sensitivity analysis, data assessment, calibration, and uncertainty analysis programs used in envi...

  19. Dramatic Change in Jupiter's Great Red Spot

    NASA Technical Reports Server (NTRS)

    Simon, A. A.; Wong, M. H.; Rogers, J. H.; Orton, G. S.; de Pater, I.; Asay-Davis, X.; Carlson, R. W.; Marcus, P. S.

    2015-01-01

    Jupiter's Great Red Spot (GRS) is one of its most distinct and enduring features, having been continuously observed since the 1800's. It currently spans the smallest latitude and longitude size ever recorded. Here we show analyses of 2014 Hubble spectral imaging data to study the color, structure and internal dynamics of this long-live storm.

  20. From Basking Ridge to the Jupiter Trojans

    NASA Technical Reports Server (NTRS)

    Englander, Jacob

    2017-01-01

    This presentation describes the activities of the Global Trajectory Optimization Lab, a subdivision of the Navigation and Mission Design Branch at NASA GSFC. The students will learn the basics of interplanetary trajectory optimization and then, as an example, the Lucy mission to the Jupiter Trojans will be described from both a science and engineering perspective.

  1. Jupiter Environmental Research & Field Studies Academy.

    ERIC Educational Resources Information Center

    Huttemeyer, Bob

    1996-01-01

    Describes the development and workings of the Jupiter Environmental Research and Field Studies Academy that focuses on enabling both teachers and students to participate in real-life learning experiences. Discusses qualifications for admittance, curriculum, location, ongoing projects, students, academics, preparation for life, problem solving, and…

  2. An intense stratospheric jet on Jupiter.

    PubMed

    Flasar, F M; Kunde, V G; Achterberg, R K; Conrath, B J; Simon-Miller, A A; Nixon, C A; Gierasch, P J; Romani, P N; Bézard, B; Irwin, P; Bjoraker, G L; Brasunas, J C; Jennings, D E; Pearl, J C; Smith, M D; Orton, G S; Spilker, L J; Carlson, R; Calcutt, S B; Read, P L; Taylor, F W; Parrish, P; Barucci, A; Courtin, R; Coustenis, A; Gautier, D; Lellouch, E; Marten, A; Prangé, R; Biraud, Y; Fouchet, T; Ferrari, C; Owen, T C; Abbas, M M; Samuelson, R E; Raulin, F; Ade, P; Césarsky, C J; Grossman, K U; Coradini, A

    2004-01-08

    The Earth's equatorial stratosphere shows oscillations in which the east-west winds reverse direction and the temperatures change cyclically with a period of about two years. This phenomenon, called the quasi-biennial oscillation, also affects the dynamics of the mid- and high-latitude stratosphere and weather in the lower atmosphere. Ground-based observations have suggested that similar temperature oscillations (with a 4-5-yr cycle) occur on Jupiter, but these data suffer from poor vertical resolution and Jupiter's stratospheric wind velocities have not yet been determined. Here we report maps of temperatures and winds with high spatial resolution, obtained from spacecraft measurements of infrared spectra of Jupiter's stratosphere. We find an intense, high-altitude equatorial jet with a speed of approximately 140 m s(-1), whose spatial structure resembles that of a quasi-quadrennial oscillation. Wave activity in the stratosphere also appears analogous to that occurring on Earth. A strong interaction between Jupiter and its plasma environment produces hot spots in its upper atmosphere and stratosphere near its poles, and the temperature maps define the penetration of the hot spots into the stratosphere.

  3. Observations of Jupiter's satellites, 1662-1972

    NASA Technical Reports Server (NTRS)

    Pierce, D. A.

    1974-01-01

    A literature search has yielded nearly 26,000 observations of the satellites of Jupiter, made from 1662 through 1972. The type (photographic; micrometer; eclipse, occultation, transit) and number of observations are tabulated in 5-year increments, and a complete bibliography is cited.

  4. Baby Jupiters Must Gain Weight Fast

    NASA Technical Reports Server (NTRS)

    2009-01-01

    This photograph from NASA's Spitzer Space Telescope shows the young star cluster NGC 2362. By studying it, astronomers found that gas giant planet formation happens very rapidly and efficiently, within less than 5 million years, meaning that Jupiter-like worlds experience a growth spurt in their infancy.

  5. JUPITER PROJECT - MERGING INVERSE PROBLEM FORMULATION TECHNOLOGIES

    EPA Science Inventory

    The JUPITER (Joint Universal Parameter IdenTification and Evaluation of Reliability) project seeks to enhance and build on the technology and momentum behind two of the most popular sensitivity analysis, data assessment, calibration, and uncertainty analysis programs used in envi...

  6. Jupiter Environmental Research & Field Studies Academy.

    ERIC Educational Resources Information Center

    Huttemeyer, Bob

    1996-01-01

    Describes the development and workings of the Jupiter Environmental Research and Field Studies Academy that focuses on enabling both teachers and students to participate in real-life learning experiences. Discusses qualifications for admittance, curriculum, location, ongoing projects, students, academics, preparation for life, problem solving, and…

  7. Jupiter Quest: A Path to Scientific Discovery.

    ERIC Educational Resources Information Center

    Bollman, Kelly A.; Rodgers, Mark H.; Mauller, Robert L.

    2001-01-01

    To experience the world of professional science, students must have access to the scientific community and be allowed to become real scientists. A partnership involving the National Aeronautics and Space Administration, the Jet Propulsion Laboratory, and the Lewis Center for Educational Research has produced Jupiter Quest, an engaging curriculum…

  8. Baby Jupiters Must Gain Weight Fast

    NASA Technical Reports Server (NTRS)

    2009-01-01

    This photograph from NASA's Spitzer Space Telescope shows the young star cluster NGC 2362. By studying it, astronomers found that gas giant planet formation happens very rapidly and efficiently, within less than 5 million years, meaning that Jupiter-like worlds experience a growth spurt in their infancy.

  9. Jupiter Polar Haze in False Color

    NASA Image and Video Library

    2017-02-01

    This false color view of Jupiter's polar haze was created by citizen scientist Gerald Eichstädt using data from the JunoCam instrument on NASA's Juno spacecraft. The image was taken on Dec. 11, 2016 at 2:30 p.m. PST (5:30 p.m. EST), when the spacecraft was 285,000 miles (459,000 kilometers) from Jupiter on the outbound leg of its third close flyby. This image is composited from four images taken through different filters: red, green, blue and methane. When the near-infrared methane image is processed with the others, the result is a false color product that highlights high clouds and high altitude hazes. The Great Red Spot and Oval BA (just below the Great Red Spot) are high in Jupiter's atmosphere, thus bright in this picture. The high-altitude haze layer over the south pole partially obscures our view of the storms below. By combining the methane data with the visible light images, we can learn about the vertical structure of Jupiter's atmosphere. http://photojournal.jpl.nasa.gov/catalog/PIA21379

  10. The Mariner Jupiter/Saturn IRIS experiment

    NASA Technical Reports Server (NTRS)

    Burke, T. E.

    1974-01-01

    After a schematic representation of the IRIS experiment, objectives of the program are outlined. Specifically data cover: (1) determination of energy balance for Jupiter and Saturn, (2) determination of methane, ammonia, hydrogen and water vapor quantities, (3) three dimensional temperature fields, (4) hydrogen-helium ratios and isotopic ratios of H/C, C/N, and C/O.

  11. Communications constraints on a Jupiter probe mission

    NASA Technical Reports Server (NTRS)

    Hinrichs, C.

    1974-01-01

    The use of the Saturn Uranus telemetry design for Jupiter entry requires the following qualifications in space probe data handling: A single dump substitute for the dual damp, a reduction in the neutral mass spectrometer rate, and providing that a second burn is made, a delta V correction.

  12. The Voyager flights to Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    1982-01-01

    The results of the mini-Grand Tour to Jupiter and Saturn by the Voyager 1 and 2 spacecraft are highlighted. Features of the spacecraft are depicted including the 11 instruments designed to probe the planets and their magnetic environments, the rings of Saturn, the fleets of satellites escorting the planets, and the interplanetary medium. Major scientific discoveries relating to these phenomena are summarized.

  13. Infrared studies of hydrocarbons on Jupiter

    NASA Astrophysics Data System (ADS)

    Kostiuk, T.; Espenak, F.; Mumma, M. J.; Romani, P.

    1989-05-01

    Measurements of ethane and ethylene emission lines on Jupiter were made using a dual CO2 laser heterodyne spectrometer. Retrieved abundances of these products of methane photolysis in the Jovian stratosphere were used to test existing photochemical models and to investigate a localized "hot spot" in the northern auroral region.

  14. Observations of Jupiter's satellites, 1662-1972

    NASA Technical Reports Server (NTRS)

    Pierce, D. A.

    1974-01-01

    A literature search has yielded nearly 26,000 observations of the satellites of Jupiter, made from 1662 through 1972. The type (photographic; micrometer; eclipse, occultation, transit) and number of observations are tabulated in 5-year increments, and a complete bibliography is cited.

  15. Asymmetries and Variations in Jupiter's Magnetosphere

    NASA Technical Reports Server (NTRS)

    Khurana, Krishan K.

    2003-01-01

    The investigation was carried out to infer the influence of solar wind on Jupiter's magnetosphere through studies of asymmetries and variations in the magnetosphere. We used the magnetic field observations from all of the pre-Galileo spacecraft and from the Galileo Prime and extended missions to understand asymmetries in magnetic field and various current systems in the magnetosphere.

  16. Infrared spectroscopy of Jupiter and Saturn

    NASA Technical Reports Server (NTRS)

    Knacke, Roger

    1988-01-01

    High resolution infrared spectoscopy provides unique insights into the chemistry and dynamics of the atmospheres of Jupiter and Saturn. The 5 micrometer spectral region, which is transparent to deep levels, is particularly useful for the identification of molecules that are present at very low (parts per billion) concentrations. These are tracers of convective and strongly non-equilibrium processes in the atmosphere. High resolution ground-based spectroscopy complements Voyager and Galileo measurements. Spectroscopy is sensitive to lower mixing levels for selected molecules, while the on-board mass spectrometers probe molecules that are spectroscopically inaccessible. Analysis and modeling of the 4.7 micrometer carbon monoxide in Jupiter was completed. CO is present at a mole fraction of 1.6 plus or minus 0.3 x 10 to the 9th power and concentrated in the troposphere. At this abundance, it must be convected upward from much deeper levels in Jupiter where the temperature is near 1100 K. Thus CO is a tracer of the deep atmosphere which is otherwise unobservable. The oxygen abundance in Jupiter (as measured by the CO abundance) is near solar. Chemical or physical process must deplete the major oxygen carrier, water. Germane, GeH4, was discovered on Saturn at amole fraction of 4 plus or minus 2 x 10 to the 10th power.

  17. Infrared spectroscopy of Jupiter and Saturn

    NASA Astrophysics Data System (ADS)

    Knacke, Roger

    1988-08-01

    High resolution infrared spectoscopy provides unique insights into the chemistry and dynamics of the atmospheres of Jupiter and Saturn. The 5 micrometer spectral region, which is transparent to deep levels, is particularly useful for the identification of molecules that are present at very low (parts per billion) concentrations. These are tracers of convective and strongly non-equilibrium processes in the atmosphere. High resolution ground-based spectroscopy complements Voyager and Galileo measurements. Spectroscopy is sensitive to lower mixing levels for selected molecules, while the on-board mass spectrometers probe molecules that are spectroscopically inaccessible. Analysis and modeling of the 4.7 micrometer carbon monoxide in Jupiter was completed. CO is present at a mole fraction of 1.6 plus or minus 0.3 x 10 to the 9th power and concentrated in the troposphere. At this abundance, it must be convected upward from much deeper levels in Jupiter where the temperature is near 1100 K. Thus CO is a tracer of the deep atmosphere which is otherwise unobservable. The oxygen abundance in Jupiter (as measured by the CO abundance) is near solar. Chemical or physical process must deplete the major oxygen carrier, water. Germane, GeH4, was discovered on Saturn at amole fraction of 4 plus or minus 2 x 10 to the 10th power.

  18. The Origin of Retrograde Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Naoz, Smadar; Farr, W.; Lithwick, Y.; Rasio, F.; Teyssandier, J.

    2011-09-01

    The search for extra-solar planets has led to the surprising discovery of many Jupiter-like planets in very close proximity to their host star, the so-called ``hot Jupiters'' (HJ). Even more surprisingly, many of these HJs have orbits that are eccentric or highly inclined with respect to the equator of the star, and some (about 25%) even orbiting counter to the spin direction of the star. This poses a unique challenge to all planet formation models. We show that secular interactions between Jupiter-like planet and another perturber in the system can easily produce retrograde HJ orbits. We show that in the frame of work of secular hierarchical triple system (the so-called Kozai mechanism) the inner orbit's angular momentum component parallel to the total angular momentum (i.e., the z-component of the inner orbit angular momentum) need not be constant. In fact, it can even change sign, leading to a retrograde orbit. A brief excursion to very high eccentricity during the chaotic evolution of the inner orbit allows planet-star tidal interactions to rapidly circularize that orbit, decoupling the planets and forming a retrograde hot Jupiter. We estimate the relative frequencies of retrograde orbits and counter to the stellar spin orbits using Monte Carlo simulations, and find that the they are consistent with the observations. The high observed incidence of planets orbiting counter to the stellar spin direction may suggest that planet--planet secular interactions are an important part of their dynamical history.

  19. Influence of solar activity on Jupiter's atmosphere

    NASA Astrophysics Data System (ADS)

    Vidmachenko, A. P.

    2016-05-01

    The influx of solar energy to different latitudes while Jupiter's orbital motion around the Sun varies significantly. This leads to a change in the optical and physical characteristics of its atmosphere. Analysis of the data for 1850-1991 on determination of the integral magnitude Mj Jupiter in the V filter, and a comparison with the changes of the Wolf numbers W, characterizing the variations of solar activity (SA) - showed that the change of Mj in maxima of the SA - has minima for odd, and maximums - for the even of SA cycles. That is, changing of the Jupiter brightness in visible light is much evident 22.3-year magnetic cycle, and not just about the 11.1-year cycle of solar activity. Analysis of the obtained in 1960-2015 data on the relative distribution of brightness along the central meridian of Jupiter, for which we calculated the ratio of the brightness Aj of northern to the southern part of the tropical and temperate latitudinal zones, allowed to approximate the change of Aj by sinusoid with a period of 11.91±0.07 earth years. Comparison of time variation of Aj from changes in the index of SA R, and the movement of the planet in its orbit - indicates the delay of response of the visible cloud layer in the atmosphere of the Sun's exposure mode for 6 years. This value coincides with the radiative relaxation of the hydrogen-helium atmosphere

  20. Europa--Jupiter's Icy Ocean Moon

    NASA Technical Reports Server (NTRS)

    Lowes, L.

    1999-01-01

    Europa is a puzzle. The sixth largest moon in our solar system, Europa confounds and intrigues scientists. Few bodies in the solar system have attracted as much scientific attention as this moon of Jupiter because of its possible subsurface ocean of water. The more we learn about this icy moon, the more questions we have.

  1. Jupiter Exploration: High Risk and High Rewards

    NASA Astrophysics Data System (ADS)

    Kite, Edwin S.

    2004-12-01

    Jupiter exploration is big science, and only the United States can afford self-contained missions to the gas giant and its four planet-sized moons. The Galileo spacecraft, which was recently flown into Jupiter to prevent it from contaminating Europa's ocean, cost $1.6 billion. Despite the failure of its High Gain Antenna (HGA), Galileo discovered briny, subsurface oceans on Europa, Ganymede, and Callisto; globally mapped all four Galilean moons; monitored Io's volcanic activity; carried out a 7-year study of the Jovian magnetosphere; and dropped an atmospheric probe into Jupiter's upper cloud layer. Of these achievements, the most significant is the indirect detection of a deep subsurface liquid-water layer on Europa [Pappalardo et al., 1999; Kivelson et al., 2000]. The case for a Europan ecosystem can be made [e.g., Marion et al., 2004], although it is important to remember the energetic and biogeochemical limits on putative Europan life [e.g., Soare et al., 2002]. Europa's low moment of inertia (0.346 +/- 0.005 MR2) suggests a silicate mantle below the ocean, permitting chemical exchanges between ocean and silicates, as occurs on Earth. Europa's surface is geologically young, likely emplaced 20-180 million years ago. Any recycling of surficial icy crust into the ocean could add oxygen, sulfur, and organic compounds, either impact-delivered or generated in situ by UV irradiation and the implantation of ionized particles from Jupiter's radiation belts.

  2. On the Radius Anomaly of Hot Jupiters: Reexamination of the Possibility and Impact of Layered Convection

    NASA Astrophysics Data System (ADS)

    Kurokawa, Hiroyuki; Inutsuka, Shu-ichiro

    2015-12-01

    Observations have revealed that a significant number of hot Jupiters have anomalously large radii. Layered convection induced by compositional inhomogeneity has been proposed to account for the radius anomaly of hot Jupiters. To reexamine the impact of the compositional inhomogeneity, we perform an evolutionary calculation by determining the convection regime at each evolutionary time step according to the criteria from linear analyses. It is shown that the impact is limited in the case of the monotonic gradient of heavy-element abundance. The layered convection is absent for the first 1 Gyr from the formation of hot Jupiters, and instead overturning convection develops. The superadiabaticity of the temperature gradient is limited by the neutrally stable state for the Ledoux stability criterion. The effect of the increased mass of heavy elements essentially compensates the effect of the delayed contraction on the planetary radius caused by compositional inhomogeneity. In addition, even in the case where the layered convection is artificially imposed, this mechanism requires extremely thin layers (˜101-103 cm) to account for the observed radius anomaly. The long-term stability of such thin layers remains to be studied. Therefore, if the criteria adopted in this paper are adequate, it might be difficult to explain the inflated radii of hot Jupiters by the monotonic gradient of heavy-element abundance alone.

  3. EVIDENCE FOR THE TIDAL DESTRUCTION OF HOT JUPITERS BY SUBGIANT STARS

    SciTech Connect

    Schlaufman, Kevin C.; Winn, Joshua N. E-mail: jwinn@mit.edu

    2013-08-01

    Tidal transfer of angular momentum is expected to cause hot Jupiters to spiral into their host stars. Although the timescale for orbital decay is very uncertain, it should be faster for systems with larger and more evolved stars. Indeed, it is well established that hot Jupiters are found less frequently around subgiant stars than around main-sequence stars. However, the interpretation of this finding has been ambiguous, because the subgiants are also thought to be more massive than the F- and G-type stars that dominate the main-sequence sample. Consequently, it has been unclear whether the absence of hot Jupiters is due to tidal destruction or inhibited formation of those planets around massive stars. Here we show that the Galactic space motions of the planet-hosting subgiant stars demand that on average they be similar in mass to the planet-hosting main-sequence F- and G-type stars. Therefore the two samples are likely to differ only in age, and provide a glimpse of the same exoplanet population both before and after tidal evolution. As a result, the lack of hot Jupiters orbiting subgiants is clear evidence for their tidal destruction. Questions remain, though, about the interpretation of other reported differences between the planet populations around subgiants and main-sequence stars, such as their period and eccentricity distributions and overall occurrence rates.

  4. Jupiter in blue, ultraviolet and near infrared

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These three images of Jupiter, taken through the narrow angle camera of NASA's Cassini spacecraft from a distance of 77.6 million kilometers (48.2 million miles) on October 8, reveal more than is apparent to the naked eye through a telescope.

    The image on the left was taken through the blue filter. The one in the middle was taken in the ultraviolet. The one on the right was taken in the near infrared.

    The blue-light filter is within the part of the electromagnetic spectrum detectable by the human eye. The appearance of Jupiter in this image is, consequently, very familiar. The Great Red Spot (below and to the right of center) and the planet's well-known banded cloud lanes are obvious. The brighter bands of clouds are called zones and are probably composed of ammonia ice particles. The darker bands are called belts and are made dark by particles of unknown composition intermixed with the ammonia ice.

    Jupiter's appearance changes dramatically in the ultraviolet and near infrared images. These images are near negatives of each other and illustrate the way in which observations in different wavelength regions can reveal different physical regimes on the planet.

    All gases scatter sunlight efficiently at short wavelengths; this is why the sky appears blue on Earth. The effect is even more pronounced in the ultraviolet. The gases in Jupiter's atmosphere, above the clouds, are no different. They scatter strongly in the ultraviolet, making the deep banded cloud layers invisible in the middle image. Only the very high altitude haze appears dark against the bright background. The contrast is reversed in the near infrared, where methane gas, abundant on Jupiter but not on Earth, is strongly absorbing and therefore appears dark. Again the deep clouds are invisible, but now the high altitude haze appears relatively bright against the dark background. High altitude haze is seen over the poles and the equator.

    The Great Red Spot, prominent in all images, is

  5. JunoCam's Imaging of Jupiter

    NASA Astrophysics Data System (ADS)

    Orton, Glenn; Hansen, Candice; Momary, Thomas; Caplinger, Michael; Ravine, Michael; Atreya, Sushil; Ingersoll, Andrew; Bolton, Scott; Rogers, John; Eichstaedt, Gerald

    2017-04-01

    Juno's visible imager, JunoCam, is a wide-angle camera (58° field of view) with 4 color filters: red, green and blue (RGB) and methane at 889 nm, designed for optimal imaging of Jupiter's poles. Juno's elliptical polar orbit offers unique views of Jupiter's polar regions with spatial scales as good as 50 km/pixel. At closest approach ("perijove") the images have spatial scale down to ˜3 km/pixel. As a push-frame imager on a rotating spacecraft, JunoCam uses time-delayed integration to take advantage of the spacecraft spin to extend integration time to increase signal. Images of Jupiter's poles reveal a largely uncharted region of Jupiter, as nearly all earlier spacecraft except Pioneer 11 have orbited or flown by close to the equatorial plane. Poleward of 64-68° planetocentric latitude, Jupiter's familiar east-west banded structure breaks down. Several types of discrete features appear on a darker, bluish-cast background. Clusters of circular cyclonic spirals are found immediately around the north and south poles. Oval-shaped features are also present, ranging in size down to JunoCam's resolution limits. The largest and brightest features usually have chaotic shapes; animations over ˜1 hour can reveal cyclonic motion in them. Narrow linear features traverse tens of degrees of longitude and are not confined in latitude. JunoCam also detected optically thin clouds or hazes that are illuminated beyond the nightside ˜1-bar terminator; one of these detected at Perijove lay some 3 scale heights above the main cloud deck. Tests have been made to detect the aurora and lightning. Most close-up images of Jupiter have been acquired at lower latitudes within 2 hours of closest approach. These images aid in understanding the data collected by other instruments on Juno that probe deeper in the atmosphere. When Jupiter was too close to the sun for ground-based observers to collect data between perijoves 1 and 2, JunoCam took a sequence of routine images to monitor large

  6. Jupiter in blue, ultraviolet and near infrared

    NASA Technical Reports Server (NTRS)

    2000-01-01

    These three images of Jupiter, taken through the narrow angle camera of NASA's Cassini spacecraft from a distance of 77.6 million kilometers (48.2 million miles) on October 8, reveal more than is apparent to the naked eye through a telescope.

    The image on the left was taken through the blue filter. The one in the middle was taken in the ultraviolet. The one on the right was taken in the near infrared.

    The blue-light filter is within the part of the electromagnetic spectrum detectable by the human eye. The appearance of Jupiter in this image is, consequently, very familiar. The Great Red Spot (below and to the right of center) and the planet's well-known banded cloud lanes are obvious. The brighter bands of clouds are called zones and are probably composed of ammonia ice particles. The darker bands are called belts and are made dark by particles of unknown composition intermixed with the ammonia ice.

    Jupiter's appearance changes dramatically in the ultraviolet and near infrared images. These images are near negatives of each other and illustrate the way in which observations in different wavelength regions can reveal different physical regimes on the planet.

    All gases scatter sunlight efficiently at short wavelengths; this is why the sky appears blue on Earth. The effect is even more pronounced in the ultraviolet. The gases in Jupiter's atmosphere, above the clouds, are no different. They scatter strongly in the ultraviolet, making the deep banded cloud layers invisible in the middle image. Only the very high altitude haze appears dark against the bright background. The contrast is reversed in the near infrared, where methane gas, abundant on Jupiter but not on Earth, is strongly absorbing and therefore appears dark. Again the deep clouds are invisible, but now the high altitude haze appears relatively bright against the dark background. High altitude haze is seen over the poles and the equator.

    The Great Red Spot, prominent in all images, is

  7. Modelling of Trapped Radiation Near Jupiter

    NASA Technical Reports Server (NTRS)

    Mihalov, John D.; DeVincenzi, Donald (Technical Monitor)

    2001-01-01

    Energetic (62 to approx. 130 MeV) proton fluxes measured with the Galileo Probe inside Jupiter's main ring (radii 122,500 to 128,940 km) show a modest increase as Jupiter is approached. Solutions of a reduced (1-d) equatorial diffusion equation with-constant losses described by a lifetime tau match those data for tau greater than or equal to 10(exp 9) s for diffusion coefficient D(sub LL) = 10(exp -9) L(exp 4)/s, 10(exp -9) L(exp -3)/s, or 10(exp -10) L(exp 4)/s (this particle population may be undergoing nearly loss-free inward radial diffusion). Tau would increase as Jupiter is approached if its value were determined by pitch angle scattering due to EM wave-particle interactions. if the absolute amplitudes of the waves' magnetic fluctuations did not vary with radial distance. Exploration of numerical solutions of the diffusive transport equation for Jupiter's magnetospheric ions at die planetary ring and closer to Jupiter has been done. Explicit range-energy relationships for energy loss in ring matter (SiO2), modeled as a continuous disk, are incorporated. A spatial resolution of approx. 1000 km in the radial direction is used in the vicinity of the main ring; off-equatorial ion fluxes have been included (assuming the atmosphere is a perfect absorber). For protons the maximum effect of energy loss in the microscopic size range of ring particles is expected at energies approx. 0.1 Mev. Presumably there could be sufficiently large, unobserved bodies within the ring that would have to be modeled as discrete objects, as planetary satellites would be. Within limitations of the model and computational resources it's planned to characterize solutions for transport of magnetospheric ions past the planetary ring; the procedures that are used are fairly well known and may be applied generally to the simpler magnetospheric models.

  8. The EJSM Jupiter-Europa Orbiter: Mission Overview

    NASA Astrophysics Data System (ADS)

    Pappalardo, R. T.; Clark, K.; Greeley, R.; Hendrix, A. R.; Tan-Wang, G.; Lock, R.; van Houten, T.; Ludwinski, J.; Petropoulis, A.; Jun, I.; Boldt, J.; Kinnison, J.

    2008-09-01

    Missions to explore Europa have been imagined ever since the Voyager mission first suggested that Europa was geologically very young. Subsequently, Galileo supplied fascinating new insights into that satellite's secrets. The Jupiter Europa Orbiter (JEO) would be the NASA-led portion of the Europa Jupiter System Mission (EJSM), an international mission with orbiters developed by NASA, ESA and possibly JAXA. JEO would address key components of the complete EJSM science objectives and would be designed to function alone or in conjunction with the ESA-led Jupiter Ganymede Orbiter and JAXA-led Jupiter Magnetospheric Orbiter. The JEO mission concept uses a single orbiter flight system which would travel to Jupiter to perform a multi-year study of the Jupiter system and Europa, including 2.5-3 years of Jupiter system science and a comprehensive Europa orbit phase of upt ot a year. This abstract describes the design concept of this mission.

  9. Ground-based Observational Characterization of Transiting Hot-Jupiter Atmosphere

    NASA Astrophysics Data System (ADS)

    Chen, G.

    2016-09-01

    -rich model is unable to explain all the data, a carbon-rich model provides a reasonable fit but violates the energy balance. The GROND emission measurements of WASP-46 b also suggest an isothermal temperature profile for its dayside atmosphere. Our K-band measurement for WASP-43 b confirms previous detections obtained in the 2.09 μm narrow band and K_S band. All three hot Jupiters seem to have very poor day to nightside heat redistribution. Furthermore, we present the analysis of optical eclipse measurements for WASP-46 b and WASP-43 b, which are either false positives or indication of reflective clouds at high altitude. Additionally, thanks to the simultaneous multi-band observing capability of GROND, a broad-band transmission spectrum is derived for WASP-43 b. Limited by current spectral resolution and precision, the atmospheric compositions can not be distinguished, indicating the necessity of the spectroscopic observations. In Chapter 6 and 7, the spectroscopic observations on the transits of HAT-P-1 b and HAT-P-32 b are summarized, respectively. Stellar light that has been transmitted through planetary terminator atmosphere carries information of atmospheric compositions. We report the first detection of the K resonance doublet absorption in HAT-P-1 b. This is the first time to resolve the K doublets in any planet. The K absorption profile consists of only narrow cores while lacks pressure-broadened wings, indicating clouds or hazes. Our optical transmission spectrum, covering the wavelength ranges of 310-520 nm and 610-1000 nm, rules out the presence of TiO and VO and the presence of pure Rayleigh-scattering hazes. Together with the 1.1-1.7 μm transmission spectrum derived by HST/WFC3, we also rule out the possibility of optically thick clouds. The current combined dataset is well explained by a nearly solar-abundance atmosphere of Na, K, H_2O, and CH_4. For HAT-P-32 b, the measured optical transmission spectrum shows signatures of TiO/VO absorption to some degree

  10. Light-Curve Survey of Jupiter Trojan Asteroids

    NASA Astrophysics Data System (ADS)

    Duffard, R.; Melita, M.; Ortiz, J. L.; Licandro, J.; Williams, I. P.; Jones, D.

    2008-09-01

    Trojan asteroids are an interesting population of minor bodies due to their dynamical characteristics, their physical properties and that they are relatively isolated located at the snow-line The main hypotheses about the origin of the Jupiter Trojans assumed that they formed either during the final stages of the planetary formation (Marzari & Scholl 1998), or during the epoch of planetary migration (Morbidelli et al. 2005), in any case more than 3.8 Gy. ago. The dynamical configuration kept the Trojans isolated from the asteroid Main Belt throughout the history of the Solar System. In spite of eventual interactions with other populations of minor bodies like the Hildas, the Jupiter family comets, and the Centaurs, their collisional evolution has been dictated mostly by the intrapopulation collisions (Marzari et al. 1996, 1997). Therefore, the Jupiter Trojans may be considered primordial bodies, whose dynamical and physical properties can provide important clues about the environment of planetary formation. The available sample of Jupiter Trojans light-curves is small and mainly restricted to the largest objects. According to the MPC-website (updated last in March 2006), the present sample of rotation periods and light-curve-amplitudes of the Jupiter Trojan asteroids is composed by 25 objects with some information about their periods and by 10 of them with only an amplitude estimation. A survey of contact binary Trojan asteroids has been done by Mann et al. 2007, where they have recorded more than 100 amplitudes from sparse-sampled light-curves and very-wellresolved rotational periods. More than 2000 Trojan asteroids have been discovered up to date, so, there is an urgent need to enlarge the sample of intrinsic rotation periods and accurate light-curve amplitudes and to extend it to smaller sizes. Results and Discusions We requested 26 nights of observation in the second semester of 2007, to begin with the survey. They were scheduled for the following instruments

  11. Jupiter's Main Ring/Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (28.5 miles) per picture element (pixel) along Jupiter's rings. Because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow, peering back toward the Sun; the ring was approximately 2.3 million kilometers (1.4 million miles) away. The arc on the far right of the image is produced when sunlight is scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts - - a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, outside the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the figure's far left side. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa (top image). A faint mist of particles can be seen above and below the main rings. This vertically extended 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. To accentuate faint features in the bottom image of the ring halo, different brightnesses are shown through color. Brightest features are white or yellow and the

  12. Jupiter's Main Ring/Ring Halo

    NASA Technical Reports Server (NTRS)

    1997-01-01

    A mosaic of four images taken through the clear filter (610 nanometers) of the solid state imaging (CCD) system aboard NASA's Galileo spacecraft on November 8, 1996, at a resolution of approximately 46 kilometers (28.5 miles) per picture element (pixel) along Jupiter's rings. Because the spacecraft was only about 0.5 degrees above the ring plane, the image is highly foreshortened in the vertical direction. The images were obtained when Galileo was in Jupiter's shadow, peering back toward the Sun; the ring was approximately 2.3 million kilometers (1.4 million miles) away. The arc on the far right of the image is produced when sunlight is scattered by small particles comprising Jupiter's upper atmospheric haze. The ring also efficiently scatters light, indicating that much of its brightness is due to particles that are microns or less in diameter. Such small particles are believed to have human-scale lifetimes, i.e., very brief compared to the solar system's age.

    Jupiter's ring system is composed of three parts - - a flat main ring, a lenticular halo interior to the main ring, and the gossamer ring, outside the main ring. The near and far arms of Jupiter's main ring extend horizontally across the mosaic, joining together at the ring's ansa, on the figure's far left side. The near arm of the ring appears to be abruptly truncated close to the planet, at the point where it passes into Jupiter's shadow. Some radial structure is barely visible across the ring's ansa (top image). A faint mist of particles can be seen above and below the main rings. This vertically extended 'halo' is unusual in planetary rings, and is probably caused by electromagnetic forces pushing the smallest grains out of the ring plane. Because of shadowing, the halo is not visible close to Jupiter in the lower right part of the mosaic. To accentuate faint features in the bottom image of the ring halo, different brightnesses are shown through color. Brightest features are white or yellow and the

  13. Three spacecraft observe Jupiter's glowing polar regions

    NASA Astrophysics Data System (ADS)

    1996-09-01

    The aurorae on Jupiter are like the Aurorae Borealis and Australis on the Earth, although visible only by ultraviolet light. They flicker in a similar way in response to variations in the solar wind of charged particles blowing from the Sun. While Galileo monitored the changing environment of particles and magnetism in Jupiter's vicinity, IUE recorded surprisingly large and rapid variations in the overall strength of the auroral activity. IUE's main 45-centimetre telescope did not supply images,but broke up the ultraviolet rays into spectra, like invisible rainbows, from which astrophysicists could deduce chemical compositions, motions and temperatures in the cosmic objects under examination. In the case of Jupiter's aurorae, the strongest emission came from activated hydrogen atoms at a wavelength of 1216 angstroms. The Hubble Space Telescope's contributions to the International Jupiter Watch included images showing variations in the form of the aurorae, and "close-up" spectra of parts of the auroral ovals. Astronomers will compare the flickering aurorae on Jupiter with concurrent monitoring of the Sun and the solar wind by the ESA-NASA SOHO spacecraft and several satellites of the Interagency Solar-Terrestrial Programme. It is notable that changes in auroral intensity by a factor of two or three occurred during the 1996 observational period, even though the Sun was in an exceptionally quiet phase, with very few sunspots. In principle, a watch on Jupiter's aurorae could become a valuable means of checking the long-range effects of solar activity, which also has important consequences for the Earth. The situation at Jupiter is quite different from the Earth's, with the moons strongly influencing the planet's space environment. But with Hubble busy with other work, any such Jupiter-monitoring programme will have to await a new ultraviolet space observatory. IUE observed Jupiter intensively in 1979-80 in conjunction with the visits of NASA's Voyager spacecraft, and

  14. LOFAR's Potential to Characterize Jupiter's Radiation Environment

    NASA Astrophysics Data System (ADS)

    de Pater, I.

    2008-09-01

    Jupiter is a strong source of radio emissions, as discovered in the early 1950s (Burke and Franklin, 1955). These first detections revealed emissions that were sporadic in character, and confined to frequencies less than 40 MHz. This component of the planet's radio emission is commonly referred to as decametric (DAM) radiation, and is attributed to electron cyclotron maser emission, emitted by keV electrons in Jupiter's auroral regions. All four giant planets and the Earth emit such radiation. To date these emissions have been studied in the timefrequency domain, since it has not been possible to image at these low frequencies. A new Low Frequency Array, LOFAR, is momentarily being build in the Netherlands. It consists of a low (~30-80 MHz) and high (~120-240 MHz) frequency band, with baselines between 100 m up to 100 km. By connecting (VLBI) with the Nancay radio telescope, baselines of 700 km can be achieved. This telescope complements the VLA (Very large Array) and ATA (Allen Telescope Array) in frequency coverage, and using the combined arrays (quasi)- simultaneously, Jupiter's radiation environment can be mapped from about 20 MHz (the low LOFAR band is still sensitive below 30 MHz, but with reduced through-put) up to 20 GHz. Jupiter emits both synchrotron and coherent cyclotron radiation at low frequencies (e.g., de Pater 2004; Zarka, 2004). Synchrotron radiation is emitted by relativistic electrons (MeV) trapped in Jupiter's radiation belts; this component of the emission has been imaged regularly at higher (> 300 MHz) frequencies. Simultaneous high resolution imaging at low frequencies will help identify the origin and mode of transport of the synchrotron radiating electrons, including their source and loss terms. At frequencies below 40 MHz LOFAR could, for the first time ever, image Jupiter's decametric (DAM) emissions. These emissions have been observed since the early 1950's, and are characterized by complex, highly organized structures in the frequency

  15. Global structure of Jupiter's magnetospheric current sheet

    NASA Astrophysics Data System (ADS)

    Khurana, Krishan K.; Schwarzl, Hannes K.

    2005-07-01

    Jupiter's magnetosphere contains a gigantic sheet-like structure located near its dipole magnetic equator that contains most of the plasma and energetic particles swirling in Jupiter's magnetosphere. Called the "current sheet," it behaves like a rigid structure inside a radial distance of ˜50 RJ where the periodic reversals of the Br component are highly predictable. Beyond a radial distance of ˜25 RJ, the tilted current sheet lags behind the dipole magnetic equator in proportion to the radial distance of the observer. On the nightside, at radial distances >50 RJ, the current sheet is seen to become parallel to the solar wind flow direction. In this work, we analyze magnetic field observations from all six spacecraft that have explored Jupiter's magnetosphere (Pioneers 10 and 11, Voyagers 1 and 2, Ulysses, and Galileo) to determine the global structure of Jupiter's current sheet. We have assembled a database of 6328 current sheet crossings by using an automated procedure which utilizes reversals in the radial component of the magnetic field to identify current sheet crossings. The assembled database of current sheet crossings spans all local times in Jupiter's magnetosphere under differing solar wind conditions. The new model is based on a further generalization of the hinged-magnetodisc models of Behannon et al. (1981) and Khurana (1992). Four new features of the improved model are that (1) close to Jupiter, the prime meridian of the current sheet (the azimuthal direction in which it attains its highest inclination) is found to be shifted by 2.2° from the VIP4 model current sheet (Connerney et al., 1998). (2) In addition to the delay caused by the wave travel time, the location of the current sheet is further delayed because of the sweep-back of the field lines. (3) The signal delay associated with wave propagation is seen to vary both with radial distance and local time, and (4) the current sheet is allowed to become parallel to the solar wind direction at

  16. Keck adaptive optics images of Jupiter's north polar cap and Northern Red Oval

    NASA Astrophysics Data System (ADS)

    de Pater, Imke; Wong, Michael H.; de Kleer, Katherine; Hammel, Heidi B.; Ádámkovics, Máté; Conrad, Al

    2011-06-01

    We present observations at near-infrared wavelengths (1-5 μm) of Jupiter's north polar region and Northern Red Oval (NN-LRS-1). The observations were taken with the near-infrared camera NIRC2 coupled to the adaptive optics system on the 10-m W.M. Keck Telescope on UT 21 August 2010. At 5-μm Jupiter's disk reveals considerable structure, including small bright rings which appear to surround all small vortices. It is striking, though, that no such ring is seen around the Northern Red Oval. In de Pater et al. [2010a. Icarus 210, 742-762], we showed that such rings also exist around all small vortices in Jupiter's southern hemisphere, and are absent around the Great Red Spot and Red Oval BA. We show here that the vertical structure and extent of the Northern Red Oval is very similar to that of Jupiter's Red Oval BA. These new observations of the Northern Red Oval, therefore, support the idea of a dichotomy between small and large anticyclones, in which ovals larger than about two Rossby deformation radii do not have 5-μm bright rings. In de Pater et al. [2010a. Icarus 210, 742-762], we explained this difference in terms of the secondary circulations within the vortices. We further compare the brightness distribution of our new 5-μm images with previously published radio observations of Jupiter, highlighting the depletion of NH 3 gas over areas that are bright at 5 μm.

  17. Kepler-424 b: A 'lonely' hot Jupiter that found A companion

    SciTech Connect

    Endl, Michael; Caldwell, Douglas A.; Barclay, Thomas; Huber, Daniel; Havel, Mathieu; Howell, Steve B.; Quintana, Elisa; Isaacson, Howard; Buchhave, Lars A.; Brugamyer, Erik; Robertson, Paul; Cochran, William D.; MacQueen, Phillip J.; Lucas, Phillip; Fischer, Debra; Ciardi, David R.

    2014-11-10

    Hot Jupiter systems provide unique observational constraints for migration models in multiple systems and binaries. We report on the discovery of the Kepler-424 (KOI-214) two-planet system, which consists of a transiting hot Jupiter (Kepler-424b) in a 3.31 day orbit accompanied by a more massive outer companion in an eccentric (e = 0.3) 223 day orbit. The outer giant planet, Kepler-424c, is not detected transiting the host star. The masses of both planets and the orbital parameters for the second planet were determined using precise radial velocity (RV) measurements from the Hobby-Eberly Telescope (HET) and its High Resolution Spectrograph (HRS). In stark contrast to smaller planets, hot Jupiters are predominantly found to be lacking any nearby additional planets; they appear to be {sup l}onely{sup .} This might be a consequence of these systems having a highly dynamical past. The Kepler-424 planetary system has a hot Jupiter in a multiple system, similar to υ Andromedae. We also present our results for Kepler-422 (KOI-22), Kepler-77 (KOI-127), Kepler-43 (KOI-135), and Kepler-423 (KOI-183). These results are based on spectroscopic data collected with the Nordic Optical Telescope (NOT), the Keck 1 telescope, and HET. For all systems, we rule out false positives based on various follow-up observations, confirming the planetary nature of these companions. We performed a comparison with planetary evolutionary models which indicate that these five hot Jupiters have heavy element contents between 20 and 120 M {sub ⊕}.

  18. Kepler-424 b: A "Lonely" Hot Jupiter that Found a Companion

    NASA Astrophysics Data System (ADS)

    Endl, Michael; Caldwell, Douglas A.; Barclay, Thomas; Huber, Daniel; Isaacson, Howard; Buchhave, Lars A.; Brugamyer, Erik; Robertson, Paul; Cochran, William D.; MacQueen, Phillip J.; Havel, Mathieu; Lucas, Phillip; Howell, Steve B.; Fischer, Debra; Quintana, Elisa; Ciardi, David R.

    2014-11-01

    Hot Jupiter systems provide unique observational constraints for migration models in multiple systems and binaries. We report on the discovery of the Kepler-424 (KOI-214) two-planet system, which consists of a transiting hot Jupiter (Kepler-424b) in a 3.31 day orbit accompanied by a more massive outer companion in an eccentric (e = 0.3) 223 day orbit. The outer giant planet, Kepler-424c, is not detected transiting the host star. The masses of both planets and the orbital parameters for the second planet were determined using precise radial velocity (RV) measurements from the Hobby-Eberly Telescope (HET) and its High Resolution Spectrograph (HRS). In stark contrast to smaller planets, hot Jupiters are predominantly found to be lacking any nearby additional planets; they appear to be "lonely". This might be a consequence of these systems having a highly dynamical past. The Kepler-424 planetary system has a hot Jupiter in a multiple system, similar to \\upsilon Andromedae. We also present our results for Kepler-422 (KOI-22), Kepler-77 (KOI-127), Kepler-43 (KOI-135), and Kepler-423 (KOI-183). These results are based on spectroscopic data collected with the Nordic Optical Telescope (NOT), the Keck 1 telescope, and HET. For all systems, we rule out false positives based on various follow-up observations, confirming the planetary nature of these companions. We performed a comparison with planetary evolutionary models which indicate that these five hot Jupiters have heavy element contents between 20 and 120 M ⊕. Based on observations obtained with the Hobby-Eberly Telescope, which is a joint project of the University of Texas at Austin, the Pennsylvania State University, Stanford University, Ludwig-Maximilians-Universität München, and Georg-August-Universität Göttingen.

  19. Understanding of Jupiter's Atmosphere after the Galileo Probe Entry

    NASA Technical Reports Server (NTRS)

    Fonda, Mark (Technical Monitor); Young, Richard E.

    2003-01-01

    Instruments on the Galileo probe measured composition, cloud properties, thermal structure, winds, radiative energy balance, and electrical properties of the Jovian atmosphere. As expected the probe results confirm some expectations about Jupiter's atmosphere, refute others, and raise new questions which still remain unanswered. This talk will concentrate on those aspects of the probe observations which either raised new questions or remain unresolved. The Galileo probe observations of composition and clouds provided some of the biggest surprises of the mission. Helium abundance measured by the probe differed significantly from the remote sensing derivations from Voyager. Discrepancy between the Voyager helium abundance determinations for Jupiter and the Galileo probe value have now led to a considerably increased helium determination for Saturn. Global abundance of N in the form of ammonia was observed to be super-solar by approximately the same factor as carbon, in contrast to expectations that C/N would be significantly larger than solar. This has implications for the formation and evolution of Jupiter. The cloud structure was not what was generally anticipated, even though most previous remote sensing results below the uppermost cloud referred to 5 micron hot spots, local regions with reduced cloud opacity. The Galileo probe descended in one of these hot spots. Only a tenuous, presumed ammomium hydrosulfide, cloud was detected, and no significant water cloud or super-solar water abundance was measured. The mixing ratios as a function of depth for the condensibles ammonia, hydrogen sulfide, and water, exhibited no apparent correlation with either condensation levels or with each other, an observation that is still a puzzle, although there are now dynamical models of hot spots which show promise in being able to explain such behavior. Probe tracked zonal winds show that wind magnitude increases with depth to pressures of about 4 bars, with the winds extending to

  20. Europa Planetary Protection for Juno Jupiter Orbiter

    NASA Technical Reports Server (NTRS)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2010-01-01

    NASA's Juno mission launched in 2011 and will explore the Jupiter system starting in 2016. Juno's suite of instruments is designed to investigate the atmosphere, gravitational fields, magnetic fields, and auroral regions. Its low perijove polar orbit will allow it to explore portions of the Jovian environment never before visited. While the Juno mission is not orbiting or flying close to Europa or the other Galilean satellites, planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design.The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  1. The dusk flank of Jupiter's magnetosphere.

    PubMed

    Kurth, W S; Gurnett, D A; Hospodarsky, G B; Farrell, W M; Roux, A; Dougherty, M K; Joy, S P; Kivelson, M G; Walker, R J; Crary, F J; Alexander, C J

    2002-02-28

    Limited single-spacecraft observations of Jupiter's magnetopause have been used to infer that the boundary moves inward or outward in response to variations in the dynamic pressure of the solar wind. At Earth, multiple-spacecraft observations have been implemented to understand the physics of how this motion occurs, because they can provide a snapshot of a transient event in progress. Here we present a set of nearly simultaneous two-point measurements of the jovian magnetopause at a time when the jovian magnetopause was in a state of transition from a relatively larger to a relatively smaller size in response to an increase in solar-wind pressure. The response of Jupiter's magnetopause is very similar to that of the Earth, confirming that the understanding built on studies of the Earth's magnetosphere is valid. The data also reveal evidence for a well-developed boundary layer just inside the magnetopause.

  2. The Escaping Upper Atmospheres of Hot Jupiters

    NASA Astrophysics Data System (ADS)

    Davidson, Eric; Jones, Gabrielle; Uribe, Ana; Carson, Joseph

    2017-01-01

    Hot Jupiters are massive gaseous planets which orbit closely to their parent star. The strong stellar irradiation at these small orbital separations causes the temperature of the upper atmosphere of the planet to rise. This can cause the planet's atmosphere to escape into space, creating an exoplanet outflow. We ascertained which factors determine the presence and structure of these outflows by creating one dimensional simulations of the density, pressure, velocity, optical depth, and neutral fraction of hot Jupiter atmospheres. This was done for planets of masses and radii ranging from 0.5-1.5 Mj and 0.5-1.5 Rj. We found the outflow rate to be highest for a planet of 0.5 Mj and 1.5 Rj at 5.3×10-14 Mj/Yr. We also found that the higher the escape velocity, the lower the chance of the planet having an outflow.

  3. Europa Planetary Protection for Juno Jupiter Orbiter

    NASA Technical Reports Server (NTRS)

    Bernard, Douglas E.; Abelson, Robert D.; Johannesen, Jennie R.; Lam, Try; McAlpine, William J.; Newlin, Laura E.

    2010-01-01

    NASA's Juno mission launched in 2011 and will explore the Jupiter system starting in 2016. Juno's suite of instruments is designed to investigate the atmosphere, gravitational fields, magnetic fields, and auroral regions. Its low perijove polar orbit will allow it to explore portions of the Jovian environment never before visited. While the Juno mission is not orbiting or flying close to Europa or the other Galilean satellites, planetary protection requirements for avoiding the contamination of Europa have been taken into account in the Juno mission design.The science mission is designed to conclude with a deorbit burn that disposes of the spacecraft in Jupiter's atmosphere. Compliance with planetary protection requirements is verified through a set of analyses including analysis of initial bioburden, analysis of the effect of bioburden reduction due to the space and Jovian radiation environments, probabilistic risk assessment of successful deorbit, Monte-Carlo orbit propagation, and bioburden reduction in the event of impact with an icy body.

  4. The EJSM Jupiter Europa Orbiter: Planning Payload

    NASA Astrophysics Data System (ADS)

    Pappalardo, R. T.; Clark, K.; Greeley, R.; Hendrix, A. R.; Boldt, J.; Tan-Wang, G.; Lock, R.; van Houten, T.; Ludwinski, J.

    2008-09-01

    In the decade since the first return of Europa data by the Galileo spacecraft, the scientific understanding of Europa has greatly matured leading to the formulation of sophisticated new science objectives to be addressed through the acquisition of new data. The Jupiter Europa Orbiter (JEO) is one component of the proposed multi-spacecraft Europa Jupiter System Mission (EJSM) designed to obtain data in support of these new science objectives. The JEO planning payload, while notional, is used to quantify engineering aspects of the mission and spacecraft design, and operational scenarios required to obtain the data necessary to meet the science objectives. The instruments were defined to understand the viability of an approach to meet the measurement objectives, perform in the radiation environment and meet the planetary protection requirements. The actual instrument suite would ultimately be the result of an Announcement of Opportunity (AO) selection process carried out by NASA.

  5. Radiation Environment for the Jupiter Europa Orbiter

    NASA Astrophysics Data System (ADS)

    Jun, Insoo

    2008-09-01

    One of the major challenges for the Jupiter Europa Orbiter (JEO) mission would be that the spacecraft should be designed to survive an intense radiation environment expected at Jupiter and Europa. The proper definition of the radiation environments is the important first step, because it could affect almost every aspects of mission and spacecraft design. These include optimizing the trajectory to minimize radiation exposure, determining mission lifetime, selecting parts, materials, detectors and sensors, shielding design, etc. The radiation environments generated for the 2008 JEO study will be covered, emphasizing the radiation environment mainly responsible for the total ionizing dose (TID) and displacement damage dose (DDD). The latest models developed at JPL will be used to generate the TID and DDD environments. Finally, the major radiation issues will be summarized, and a mitigation plan will be discussed.

  6. Juno Captures Jupiter Cloudscape in High Resolution

    NASA Image and Video Library

    2017-03-01

    This close-up view of Jupiter captures the turbulent region just west of the Great Red Spot in the South Equatorial Belt, with resolution better than any previous pictures from Earth or other spacecraft. NASA's Juno spacecraft captured this image with its JunoCam citizen science instrument when the spacecraft was a mere 5,400 miles (8,700 kilometers) above Jupiter's cloudtops on Dec. 11, 2016 at 9:14 a.m. PT (12:14 p.m. ET). Citizen scientist Sergey Dushkin produced the sublime color processing and cropped the image to draw viewers' eyes to the dynamic clouds. http://photojournal.jpl.nasa.gov/catalog/PIA21384

  7. Jupiter's Great Red Spot in True Color

    NASA Image and Video Library

    2017-07-27

    This image of Jupiter's iconic Great Red Spot (GRS) was created by citizen scientist Björn Jónsson using data from the JunoCam imager on NASA's Juno spacecraft. This true-color image offers a natural color rendition of what the Great Red Spot and surrounding areas would look like to human eyes from Juno's position. The tumultuous atmospheric zones in and around the Great Red Spot are clearly visible. The image was taken on July 10, 2017 at 07:10 p.m. PDT (10:10 p.m. EDT), as the Juno spacecraft performed its seventh close flyby of Jupiter. At the time the image was taken, the spacecraft was about 8,648 miles (13,917 kilometers) from the tops of the clouds of the planet at a latitude of -32.6 degrees. https://photojournal.jpl.nasa.gov/catalog/PIA21775

  8. Potential reconnection sites at Jupiter's magnetopause

    NASA Astrophysics Data System (ADS)

    Desroche, M. J.; Bagenal, F.; Delamere, P. A.

    2010-12-01

    We are developing a model at Jupiter based on the Cooling model of reconnected flux tube motion on Earth’s magnetopause. (Cooling et al, JGR 106, 2001) Our model will test for possible reconnection sites at the magnetopause and map the subsequent flux tube motion. We have begun this study by mapping out the Khurana magnetic field (which includes a plasma sheet, radial currents, and magnetopause currents) at the magnetopause boundary. (Khurana and Schwarzl, JGR 110, 2005) Using MHD simulations of the solar wind flow near Jupiter, (Walker et al, Planet. Space Sci. 49, 2001) we apply a gas-dynamic convection model to determine the draping of the IMF on the magnetopause, for several likely field orientations. By considering the shear angle and strengths of the magnetic fields on either side of the magnetopause, as well as the shear velocity across the boundary, we are able to conclude where on the magnetopause reconnection is likely to be viable.

  9. Crescent Jupiter with the Great Red Spot

    NASA Image and Video Library

    2017-01-13

    This image of a crescent Jupiter and the iconic Great Red Spot was created by a citizen scientist (Roman Tkachenko) using data from Juno's JunoCam instrument. You can also see a series of storms shaped like white ovals, known informally as the "string of pearls." Below the Great Red Spot a reddish long-lived storm known as Oval BA is visible. The image was taken on Dec. 11, 2016 at 2:30 p.m. PST (5:30 p.m. EST), as the Juno spacecraft performed its third close flyby of Jupiter. At the time the image was taken, the spacecraft was about 285,100 miles (458,800 kilometers) from the planet. http://photojournal.jpl.nasa.gov/catalog/PIA21376

  10. Coma morphology of Jupiter-family comets

    NASA Astrophysics Data System (ADS)

    Farnham, Tony L.

    2009-08-01

    We present a general review of cometary coma morphology, with specific reference to how it used in studies of Jupiter-family comets. We introduce the most common features that are seen in gas and dust observations, and summarize of how they are used to infer the properties of the nucleus and coma. We also expand the discussion to cover other topics relating to morphology, including the general shape of the coma (characterized by radial gradient profiles) and spatial maps of the color, albedo and polarization of the dust. We address the pros and cons of the different approaches used in the interpretation and analysis of the features. Finally, we review the results obtained for specific comets and compare the Jupiter-family comets to those from other classes.

  11. The prospect of life on Jupiter.

    NASA Technical Reports Server (NTRS)

    Ponnamperuma, C.; Molton, P.

    1973-01-01

    We have simulated electrical discharges in the Jovian atmosphere, using anhydrous methane-ammonia mixtures, and shown the formation of simple aliphatic nitriles, amino-nitriles, and their oligomers. Including hydrogen sulfide in the gas mixture, it appears that sulfur-containing amino-nitriles are not formed, since the hydrolysate of the products did not contain the corresponding amino-acids. There is a strong analogy between these reactions and the classical spark reactions simulating the primitive earth's atmosphere. We are attempting a closer simulation of Jupiter's atmosphere by using appropriate temperature and pressure conditions. It seems that prebiotic synthesis on Jupiter may have reached an advanced state. As an alternative approach we have tested the survival ability of common terrestrial microorganisms in aqueous media at 102 atmospheres pressure and at 20 C in a simulated Jovian atmosphere. E. coli, S. marcescens, A. aerogenes, and B. subtilis will all tolerate 24 hr under these conditions with little death.

  12. Launch of Jupiter-C/Explorer 1

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Launch of Jupiter-C/Explorer 1 at Cape Canaveral, Florida on January 31, 1958. After the Russian Sputnik 1 was launched in October 1957, the launching of an American satellite assumed much greater importance. After the Vanguard rocket exploded on the pad in December 1957, the ability to orbit a satellite became a matter of national prestige. On January 31, 1958, slightly more than four weeks after the launch of Sputnik.The ABMA (Army Ballistic Missile Agency) in Redstone Arsenal, Huntsville, Alabama, in cooperation with the Jet Propulsion Laboratory, launched a Jupiter from Cape Canaveral, Florida. The rocket consisted of a modified version of the Redstone rocket's first stage and two upper stages of clustered Baby Sergeant rockets developed by the Jet Propulsion Laboratory and later designated as Juno boosters for space launches

  13. Launch, Jupiter-C, Explorer 1

    NASA Technical Reports Server (NTRS)

    1958-01-01

    Launch of Jupiter-C/Explorer 1 at Cape Canaveral, Florida on January 31, 1958. After the Russian Sputnik 1 was launched in October 1957, the launching of an American satellite assumed much greater importance. After the Vanguard rocket exploded on the pad in December 1957, the ability to orbit a satellite became a matter of national prestige. On January 31, 1958, slightly more than four weeks after the launch of Sputnik.The ABMA (Army Ballistic Missile Agency) in Redstone Arsenal, Huntsville, Alabama, in cooperation with the Jet Propulsion Laboratory, launched a Jupiter from Cape Canaveral, Florida. The rocket consisted of a modified version of the Redstone rocket's first stage and two upper stages of clustered Baby Sergeant rockets developed by the Jet Propulsion Laboratory and later designated as Juno boosters for space launches

  14. The atmospheres of Mars, Venus and Jupiter.

    PubMed

    Rasool, S I; Jastrow, R

    1964-01-01

    The general properties of the atmospheres of Mars, Venus and Jupiter are reviewed. The evolutionary processes of planetary atmospheres are outlined as an introduction to a detailed discussion of the structure of the atmospheres of other planets. The most recent observational results indicate that the surface pressure on Mars could be as low as 20 mb, and the amount of CO2 may have a mixing ratio as high as 25% by volume. For Venus, the Mariner II results suggest that the surface temperature may actually be of the order of 600 degrees K. Also there are indications that the surface pressure on Venus could be approximately 100 atm., with the atmosphere mainly composed of N2. In the case of Jupiter, recent theoretical investigations of the atmosphere below the clouds suggest, that there may be regions in the atmosphere of very high density and pressure but at relatively low temperature, creating conditions possibly favorable to the occurrence of complex organic reactions.

  15. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view to the southeast, from between the cloud layers and over the north center of the region. The tall white clouds in the lower cloud deck are probably much like large terrestrial thunderclouds. They may be regions where atmospheric water powers vertical convection over large horizontal distances.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional to the reflectivity at 727 nm divided by that at 756 nm. This model is overly simplistic, but is based on

  16. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view to the northeast, from between the cloud layers and above the streaks in the lower cloud leading towards the hotspot. The upper haze layer has some features that match the lower cloud, such as the bright streak in the foreground of the frame. These are probably thick clouds that span several tens of vertical kilometers.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional to the reflectivity at 727 nm divided by that at 756 nm. This model is overly

  17. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view to the west, from between the cloud layers and over the patchy white clouds to the east of the hotspot. This is probably an area where moist convection is occurring over large horizontal distances, similar to the atmosphere over the equatorial ocean on Earth. The clouds are high and thick, and are observed to change rapidly over short time scales.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional to the reflectivity at 727 nm divided by that at 756

  18. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view from the southwest looking northeast, from an altitude just above the high haze layer. The streaks in the lower cloud leading towards the hotspot are visible. The upper haze layer is mostly flat, with notable small peaks that can be matched with features in the lower cloud. In reality, these areas may represent a continuous vertical cloud column.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional to the reflectivity at 727 nm divided by that at 756

  19. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view to the northeast, from between the cloud layers and above the streaks in the lower cloud leading towards the hotspot. The hotspot is clearly visible as a deep blue feature. The cloud streaks end near the hotspot, consistent with the idea that clouds traveling along these streak lines descend and evaporate as they approach the hotspot. The upper haze layer is slightly bowed upwards above the hotspot.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional

  20. Three dimensional Visualization of Jupiter's Equatorial Region

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Frames from a three dimensional visualization of Jupiter's equatorial region. The images used cover an area of 34,000 kilometers by 11,000 kilometers (about 21,100 by 6,800 miles) near an equatorial 'hotspot' similar to the site where the probe from NASA's Galileo spacecraft entered Jupiter's atmosphere on December 7th, 1995. These features are holes in the bright, reflective, equatorial cloud layer where warmer thermal emission from Jupiter's deep atmosphere can pass through. The circulation patterns observed here along with the composition measurements from the Galileo Probe suggest that dry air may be converging and sinking over these regions, maintaining their cloud-free appearance. The bright clouds to the right of the hotspot as well as the other bright features may be examples of upwelling of moist air and condensation.

    This frame is a view from above and to the south of the visualized area, showing the entire model. The entire region is overlain by a thin, transparent haze. In places the haze is high and thick, especially to the east (to the right of) the hotspot.

    Galileo is the first spacecraft to image Jupiter in near-infrared light (which is invisible to the human eye) using three filters at 727, 756, and 889 nanometers (nm). Because light at these three wavelengths is absorbed at different altitudes by atmospheric methane, a comparison of the resulting images reveals information about the heights of clouds in Jupiter's atmosphere. This information can be visualized by rendering cloud surfaces with the appropriate height variations.

    The visualization reduces Jupiter's true cloud structure to two layers. The height of a high haze layer is assumed to be proportional to the reflectivity of Jupiter at 889 nm. The height of a lower tropospheric cloud is assumed to be proportional to the reflectivity at 727 nm divided by that at 756 nm. This model is overly simplistic, but is based on more sophisticated studies of Jupiter's cloud structure. The upper