Science.gov

Sample records for 10-m class telescope

  1. High Resolution Imaging of Satellites with Ground-Based 10-m Astronomical Telescopes

    SciTech Connect

    Marois, C

    2007-01-04

    High resolution imaging of artificial satellites can play an important role in current and future space endeavors. One such use is acquiring detailed images that can be used to identify or confirm damage and aid repair plans. It is shown that a 10-m astronomical telescope equipped with an adaptive optics system (AO) to correct for atmospheric turbulence using a natural guide star can acquire high resolution images of satellites in low-orbits using a fast shutter and a near-infrared camera even if the telescope is not capable of tracking satellites. With the telescope pointing towards the satellite projected orbit and less than 30 arcsec away from a guide star, multiple images of the satellite are acquired on the detector using the fast shutter. Images can then be shifted and coadded by post processing to increase the satellite signal to noise ratio. Using the Keck telescope typical Strehl ratio and anisoplanatism angle as well as a simple diffusion/reflection model for a satellite 400 km away observed near Zenith at sunset or sunrise, it is expected that such system will produced > 10{sigma} K-band images at a resolution of 10 cm inside a 60 arcsec diameter field of view. If implemented, such camera could deliver the highest resolution satellite images ever acquired from the ground.

  2. First Resolved Images of a Spacecraft in Geostationary Orbit with the Keck-II 10 m Telescope

    DTIC Science & Technology

    2010-09-01

    2009, with the adaptive optics on the largest telescope on the planet, the 10 m Keck-II on the 14000 foot summit of Mauna Kea . 1. Observations As...part of an engineering run at the Keck-II 10 m telescope on Mauna Kea , several adaptive optics images were obtained of geostationary satellite GE-23, a...largest telescope on the planet, the 10 m Keck-II on the 14000 foot summit of Mauna Kea . 15. SUBJECT TERMS 16. SECURITY CLASSIFICATION OF: 17

  3. A computer simulation for evaluating the array performance of the 10-m/phi/ 5-element super-synthesis telescope

    NASA Astrophysics Data System (ADS)

    Morita, K.-I.; Ishiguro, M.

    1980-03-01

    The array performance in several successive configurations was examined for the 10-m(phi) 5-element super-synthesis telescope. The number of (u, v) samples was used as a criterion of optimum (u, v) coverages. The optimum solution for a given declination was obtained by a random trial method. The performance was evaluated by computer simulation using model brightness distributions.

  4. Plans for a 10-m submillimeter-wave telescope at the South Pole

    NASA Astrophysics Data System (ADS)

    Stark, Antony A.; Carlstrom, John E.; Israel, Frank P.; Menten, Karl M.; Peterson, Jeffrey B.; Phillips, Thomas G.; Sironi, Giorgio; Walker, Christopher K.

    1998-07-01

    A 10 meter diameter submillimeter-wave telescope has been proposed for installation and scientific use at the NSF Amundsen-Scott South Pole Station. Current evidence indicates that the South Pole is the best submillimeter-wave telescope site among all existing or proposed ground-based observatories. Proposed scientific programs place stringent requirements on the optical quality of the telescope design. In particular, reduction of the thermal background and offsets requires an off-axis, unblocked aperture, and the large field of view needed for survey observations requires shaped optics. This mix of design elements is well-suited for large-scale (square degree) mapping of line and continuum radiation from submillimeter-wave sources at moderate spatial resolutions (4 to 60 arcsecond beam size) and high sensitivity (milliJansky flux density levels). The telescope will make arcminute angular scale, high frequency Cosmic Microwave Background measurements from the best possible ground-based site, using an aperture which is larger than is currently possible on orbital or airborne platforms. The telescope design is homologous. Gravitational changes in pointing and focal length will be accommodated by active repositioning of the secondary mirror. The secondary support, consisting of a large, enclosed beam, permits mounting of either a standard set of Gregorian optics, or prime focus instrumentation packages for CMBR studies. A tertiary chopper is located at the exit pupil of the instrument. An optical design with a hyperboloidal primary mirror and a concave secondary mirror provides a flat focal surface. The relatively large classical aberrations present in such an optical arrangement can be small compared to diffraction at submillimeter wavelengths. Effective use of this telescope will require development of large (1000 element) arrays of submillimeter detectors which are background-limited when illuminated by antenna temperatures near 50 K.

  5. 2m class telescope project at Lijiang

    NASA Astrophysics Data System (ADS)

    Chen, Dong; Wang, Jian-Cheng; Xu, Jun; Zhang, Bai-Rong; Luo, Guo-Quan; Liu, Zhong; Tan, Hui-Song

    Supported by the ministry of science and technology, government of Yunnan Province and Chinese Academy of Sciences, a 2m class telescope project was granted. In this paper, we will first review the site, Gaomeigu, briefly, then give the details of 2m class telescope project, and finally discuss the future plans of this new telescope.

  6. Constraining the Bulk Density of 10m-Class Near-Earth Asteroid 2012 LA

    NASA Astrophysics Data System (ADS)

    Mommert, Michael; Hora, Joseph; Farnocchia, Davide; Trilling, David; Chesley, Steve; Harris, Alan; Mueller, Migo; Smith, Howard

    2016-08-01

    The physical properties of near-Earth asteroids (NEAs) provide important hints on their origin, as well as their past physical and orbital evolution. Recent observations seem to indicate that small asteroids are different than expected: instead of being monolithic bodies, some of them instead resemble loose conglomerates of smaller rocks, so called 'rubble piles'. This is surprising, since self-gravitation is practically absent in these bodies. Hence, bulk density measurements of small asteroids, from which their internal structure can be estimated, provide unique constraints on asteroid physical models, as well as models for asteroid evolution. We propose Spitzer Space Telescope observations of 10 m-sized NEA 2012 LA, which will allow us to constrain the diameter, albedo, bulk density, macroporosity, and mass of this object. We require 30 hrs of Spitzer time to detect our target with a minimum SNR of 3 in CH2. In order to interpret our observational results, we will use the same analysis technique that we used in our successful observations and analyses of tiny asteroids 2011 MD and 2009 BD. Our science goal, which is the derivation of the target's bulk density and its internal structure, can only be met with Spitzer. Our observations will produce only the third comprehensive physical characterization of an asteroid in the 10m size range (all of which have been carried out by our team, using Spitzer). Knowledge of the physical properties of small NEAs, some of which pose an impact threat to the Earth, is of importance for understanding their evolution and estimating the potential of destruction in case of an impact, as well as for potential manned missions to NEAs for either research or potential commercial uses.

  7. The 0.9 and 1.3 THz Superconducting HEB Mixer Receiver for the ASTE 10 m Telescope

    NASA Astrophysics Data System (ADS)

    Shiino, T.; Furuya, R.; Soma, T.; Sakai, T.; Watanabe, Y.; Sakai, N.; Jiang, L.; Ohguchi, O.; Maezawa, H.; Yamakura, T.; Yamamoto, S.

    2013-10-01

    We have developed low-noise waveguide-type superconducting hot electron bolometer (HEB) mixers for astronomical observations in the 0.8-1.0 and 1.3-1.5 THz bands, by using a relatively thick NbTiN superconducting film (10.8 nm). The receiver noise temperature of 350 K (DSB) at 0.81 THz and 490 K at 1.475 THz has been achieved. We have built the 0.8-1.0/1.3-1.5 THz dual band heterodyne receiver using these low noise HEB mixers, and have installed it on the ASTE (Atacama Submillimeter Telescope Experiment) 10 m telescope in Chile in 2011. The 13CO emission (J = 8-7 : 0.8813 THz) has successfully been detected toward the Orion A molecular cloud with our HEB mixer receiver.

  8. Search for the CO-dark Mass in the Central Molecular Zone by using the ASTE 10-m Telescope

    NASA Astrophysics Data System (ADS)

    Tanaka, Kunihiko

    2017-01-01

    Atomic carbon (C0) is one of the most abundant carbon-bearing species in the interstellar molecular gas, and its submillimeter lines are good tracers of low-density molecular clouds which are often dark in CO rotational lines. We present a new map of the central 150 pc region of the Milky Way in the 500 GHz [CI] line, which has been recently obtained with the ASTE 10-m telescope. The [CI] emission is brightest toward the central 5-pc region, where massive GMCs are absent. This [CI]-bright region is approximately centered toward Sgr A*, covering the entire circum-nuclear ring (CND) and the western part of the 50-km/s cloud. The C0/CO abundance ratio is 0.5-2 there, and the highest ratio is observed toward the CND but just outside of the 2-pc ring of dense gas. This discovery may suggest that the CO-dark component occupies a significant fraction of the molecular gas in the circumnuclear region.

  9. Analysis of a new class of grazing incidence spectroscopic telescope

    NASA Technical Reports Server (NTRS)

    Green, J. C.; Bowyer, S.

    1986-01-01

    The throughput and imaging properties of one of a new class of grazing incidence spectroscopic telescope are examined with a Monte Carlo ray tracing technique. The results are compared with Wolter Schwarzschild type II telescopes of similar size. The image quality of this telescope is comparable, and the control of the off-axis light is superior to the Wolter Schwarzschild design.

  10. Bright features in Neptune on 2013-2015 from ground-based observations with small (40 cm) and large telescopes (10 m)

    NASA Astrophysics Data System (ADS)

    Hueso, Ricardo; Delcroix, Marc; Baranec, Christoph; Sánchez-Lavega, Agustín; María Gómez-Forrellad, Josep; Félix Rojas, Jose; Luszcz-Cook, Statia; de Pater, Imke; de Kleer, Katherine; Colas, François; Guarro, Joan; Goczynski, Peter; Jones, Paul; Kivits, Willem; Maxson, Paul; Phillips, Michael; Sussenbach, John; Wesley, Anthony; Hammel, Heidi B.; Pérez-Hoyos, Santiago; Mendikoa, Iñigo; Riddle, Reed; Law, Nicholas M.; Sayanagi, Kunio

    2015-11-01

    Observations of Neptune over the last few years obtained with small telescopes (30-50 cm) have resulted in several detections of bright features on the planet. In 2013, 2014 and 2015, different observers have repeatedly observed features of high contrast at Neptune’s mid-latitudes using long-pass red filters. This success at observing Neptune clouds with such small telescopes is due to the presence of strong methane absorption bands in Neptune’s spectra at red and near infrared wavelengths; these bands provide good contrast for elevated cloud structures. In each case, the atmospheric features identified in the images survived at least a few weeks, but were essentially much more variable and apparently shorter-lived, than the large convective system recently reported on Uranus [de Pater et al. 2015]. The latest and brightest spot on Neptune was first detected on July 13th 2015 with the 2.2m telescope at Calar Alto observatory with the PlanetCam UPV/EHU instrument. The range of wavelengths covered by PlanetCam (from 350 nm to the H band including narrow-band and wide-band filters in and out of methane bands) allows the study of the vertical cloud structure of this bright spot. In particular, the spot is particularly well contrasted at the H band where it accounted to a 40% of the total planet brightness. Observations obtained with small telescopes a few days later provide a good comparison that can be used to scale similar structures in 2013 and 2014 that were observed with 30-50 cm telescopes and the Robo-AO instrument at Palomar observatory. Further high-resolution observations of the 2015 event were obtained in July 25th with the NIRC2 camera in the Keck 2 10-m telescope. These images show the bright spot as a compact bright feature in H band with a longitudinal size of 8,300 km and a latitudinal extension of 5,300 km, well separated from a nearby bright band. The ensemble of observations locate the structure at -41º latitude drifting at about +24.27º/day or

  11. The DAG project, a 4m class telescope: the telescope main structure performances

    NASA Astrophysics Data System (ADS)

    Marchiori, G.; Busatta, A.; Ghedin, L.; Marcuzzi, E.; Manfrin, C.; Battistel, C.; Pirnay, O.; Flebus, Carlo; Yeşilyaprak, C.; Keskin, O.; Yerli, S.

    2016-07-01

    Dogu Anatolu Gözlemevi (DAG-Eastern Anatolia Observatory) Project is a 4m class optical, near-infrared Telescope and suitable enclosure which will be located at an altitude of 3.170m in Erzurum, Turkey. The DAG telescope is a project fully funded by Turkish Ministry of Development and the Atatürk University of Astrophysics Research Telescope - ATASAM. The Project is being developed by the Belgian company AMOS (project leader), which is also the optics supplier and EIE GROUP, the Telescope Main Structure supplier and responsible for the final site integration. The design of the Telescope Main Structure fits in the EIE TBO Program which aims at developing a Dome/Telescope systemic optimization process for both performances and competitive costs based on previous project commitments like NTT, VLT, VST and ASTRI. The optical Configuration of the DAG Telescope is a Ritchey-Chretien with two Nasmyth foci and a 4m primary thin mirror controlled in shape and position by an Active Optic System. The main characteristics of the Telescope Main Structure are an Altitude-Azimuth light and rigid structure system with Direct Drive Systems for both axis, AZ Hydrostatic Bearing System and Altitude standard bearing system; both axes are equipped with Tape Encoder System. An innovative Control System characterizes the telescope performance.

  12. Variable-delay Polarization Modulators for the CLASS Telescopes

    NASA Astrophysics Data System (ADS)

    Harrington, Kathleen; CLASS Collaboration

    2017-01-01

    The search for primordial gravitational waves, imprinted on the polarization of the cosmic microwave background (CMB), has galvanized the development of polarization modulators for microwave wavelengths. Variable-delay Polarization Modulators (VPMs) are a scaleable, novel type of modulator that can be placed at the front end of a telescope. VPMs consist of a linear polarizer in front of a movable flat mirror which creates a changing phase delay between orthogonal polarization states and modulates between linear and circular polarizations. Rapid, front-end polarization modulation significantly increases instrument stability and facilitates rejection of systematic effects of due to instrument polarization.VPMs are integral to the design of the Cosmology Large Angular Scale Surveyor (CLASS) telescopes, with each of the four CLASS telescopes having a 60 cm aperture VPM as their first optical element. The CLASS VPM grids use 50 μm diameter copper plated tungsten wires spaced 150 μm apart across 62 cm. Behind the wire grid is a 60 cm flat honeycomb aluminum mirror. Rotational flexure hinges assembled into a four-bar linkage configuration allow mirror motion while constraining the parallelism with respect to the wire grid. Mirror motion is driven by a voice coil and the grid-mirror distance is measured using three 0.1 μm resolution encoders, read out synchronously with the detectors. A second, identical, reaction-canceling axis eliminates the vibrations induced by mirror motion. The 40 GHz CLASS telescope, including VPM, has been installed at the CLASS site in the Chilean Atacama Desert and production of the next three CLASS VPMs is ongoing.

  13. Sizing of a Raven-Class Telescope Using Performance Sensitivities

    NASA Astrophysics Data System (ADS)

    Coder, R.; Holzinger, M.

    2013-09-01

    This work details the sizing and selection of a Raven-class telescope to be constructed at the Georgia Institute of Technology, and seeks to make four main contributions. The first is a concise yet comprehensive summary of important sizing relationships and meaningful assumptions that comprise a design methodology for Raven-class telescopes. The second is the computation of local sensitivity relationships, which identify the variables that have the greatest impact on Raven system performance metrics. The third is the development of a novel performance metric that measures the amount of information generated by a single Raven. The derived sensitivities can be used to quantify the amount of improvement in system performance per unit cost. Finally, Raven system performance metrics are used to construct several Pareto frontiers for Ravens operating in different optical environments. The most important insight provided by these Pareto frontiers is that the conventional wisdom for utilizing short focal lengths and large pixel sizes to realize the best detection capability does not hold for Raven-class telescopes located in optically noisy environments, such as Atlanta. These plots also highlight the diminishing return of increasingly large aperture diameters, demonstrating the value of the Raven design paradigm.

  14. New 50-m-class single-dish telescope: Large Submillimeter Telescope (LST)

    NASA Astrophysics Data System (ADS)

    Kawabe, Ryohei; Kohno, Kotaro; Tamura, Yoichi; Takekoshi, Tatsuya; Oshima, Tai; Ishii, Shun

    2016-08-01

    We report on a plan to construct a 50-m-class single-dish telescope, the Large Submillimeter Telescope (LST). The conceptual design and key science behind the LST are presented, together with its tentative specifications. This telescope is optimized for wide-area imaging and spectroscopic surveys in the 70-420 GHz frequency range, which spans the main atmospheric windows at millimeter and submillimeter wavelengths for good observation sites such as the Atacama Large Millimeter/submillimeter Array (ALMA) site in Chile. We also target observations at higher frequencies of up to 1 THz, using an inner high-precision surface. Active surface control is required in order to correct gravitational and thermal deformations of the surface, and will be useful for correction of the wind-load deformation. The LST will facilitate new discovery spaces such as wide-field imaging with both continuum and spectral lines, along with new developments for time-domain science. Through exploitation of its synergy with ALMA and other telescopes, the LST will contribute to research on a wide range of topics in the fields of astronomy and astrophysics, e.g., astrochemistry, star formation in our Galaxy and galaxies, the evolution of galaxy clusters via the Sunyaev-Zel'dovich (SZ) effect, the search for transients such as γ-ray burst reverse shocks produced during the epoch of re-ionization, electromagnetic follow up of detected gravitational wave sources, and examination of general relativity in the vicinity of super massive black holes via submillimeter very-long-baseline interferometry (VLBI).

  15. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Stansbery, E. G.; Cowardin, H. M.; Kervin, P.; Hickson, P.

    2013-01-01

    The Meter Class Autonomous Telescope (MCAT) is the newest optical sensor dedicated to NASA s mission to characterize the space debris environment. It is the successor to a series of optical telescopes developed and operated by the JSC Orbital Debris Program Office (ODPO) to monitor and assess the debris environment in (1) Low Earth Orbit (LEO), (2) Medium Earth Orbit (MEO), and (3) Geosynchronous Orbit (GEO), with emphasis on LEO and GEO altitudes. A joint NASA-Air Force Research Labs project, MCAT is a 1.3m optical telescope dedicated to debris research. Its optical path and sensor yield a large survey fence at the cutting edge of current detector performance. It has four primary operational observing modes, two of which were not computationally feasible a decade ago. Operations are supported by a sophisticated software suite that monitors clouds and weather conditions, and controls everything from data collection to dome rotation to processing tens of GB of imagery data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry, precision astrometry, automated reacquisition capability, and the ability to process all data at the acquisition rate, MCAT is capable of producing and processing a volume and quality of data far in excess of any current (or prior) ODPO operations. This means higher fidelity population inputs and eliminating the multi-year backlog from acquisition-to-product typical of optical campaigns. All of this is possible given a suitable observing location. Originally planned for the island of Legan, part of the Kwajalein Atoll Islands, recent developments have led to a change in venue. Specifically, the Ground-based Electro-Optical Deep Space Surveillance, or GEODSS, System of telescopes is the United States major tracking system for deep space. This network consists of telescopes in Maui, Hawaii; Diego Garcia (Indian Ocean), and Socorro, New Mexico. A fourth optical telescope, though

  16. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Astrophysics Data System (ADS)

    Lederer, S.; Stansbery, E. G.; Cowardin, H. M.; Kervin, P.; Hickson, P.

    2013-09-01

    The Meter Class Autonomous Telescope (MCAT) is the newest optical sensor dedicated to NASA's mission to characterize the space debris environment. It is the successor to a series of optical telescopes developed and operated by the JSC Orbital Debris Program Office (ODPO) to monitor and assess the debris environment in (1) Low Earth Orbit (LEO), (2) Medium Earth Orbit (MEO), and (3) Geosynchronous Orbit (GEO), with emphasis on LEO and GEO altitudes. A joint NASA-Air Force Research Labs project, MCAT is a 1.3m optical telescope dedicated to debris research. Its optical path and sensor yield a large survey fence at the cutting edge of current detector performance. It has four primary operational observing modes, two of which were not computationally feasible a decade ago. Operations are supported by a sophisticated software suite that monitors clouds and weather conditions, and controls everything from data collection to dome rotation to processing tens of GB of imagery data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry, precision astrometry, automated re-acquisition capability, and the ability to process all data at the acquisition rate, MCAT is capable of producing and processing a volume and quality of data far in excess of any current (or prior) ODPO operations. This means higher fidelity population inputs and eliminating the multi-year backlog from acquisition-to-product typical of optical campaigns. All of this is possible given a suitable observing location. Originally planned for the island of Legan, part of the Kwajalein Atoll Islands, recent developments have led to a change in venue. Specifically, the Ground-based Electro-Optical Deep Space Surveillance, or GEODSS, System of telescopes is the United States' major tracking system for deep space. This network consists of telescopes in Maui, Hawaii; Diego Garcia (Indian Ocean), and Socorro, New Mexico. A fourth optical telescope, though

  17. The NASA Meter Class Autonomous Telescope: Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Stansbery, E. G.; Cowardin, H. M.; Hickson, P.; Pace, L. F.; Abercromby, K. J.; Kervin, P. W.

    2013-01-01

    The Meter Class Autonomous Telescope (MCAT) is the newest optical sensor dedicated to NASA's mission to characterize the space debris environment. It is the successor to a series of optical telescopes developed and operated by the JSC Orbital Debris Program Office (ODPO) to monitor and assess the debris environment in (1) Low Earth Orbit (LEO), (2) Medium Earth Orbit (MEO), and (3) Geosynchronous Orbit (GEO), with emphasis on LEO and GEO altitudes. A joint NASA - Air Force Research Labs project, MCAT is a 1.3m optical telescope dedicated to debris research. Its optical path and sensor yield a large survey fence at the cutting edge of current detector performance. It has four primary operational observing modes, two of which were not computationally feasible a decade ago. Operations are supported by a sophisticated software suite that monitors clouds and weather conditions, and controls everything from data collection to dome rotation to processing tens of gigabytes of image data nightly. With fainter detection limits, precision detection, acquisition and tracking of targets, multi-color photometry, precision astrometry, automated re-acquisition capability, and the ability to process all data at the acquisition rate, MCAT is capable of producing and processing a volume and quality of data far in excess of any current (or prior) ODPO operations. This means higher fidelity population inputs and eliminating the multi-year backlog from acquisition-to-product typical of optical campaigns. All of this is possible given a suitable observing location. Ascension Island offers numerous advantages. As a British overseas territory with a US Air Force base presence, the necessary infrastructure and support already exists. It is located mid-way between Brazil and Africa at 7.93S latitude and 14.37 W longitude. With the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) asset in Moron, Spain shutting down, this presents access to the sky from a unique latitude

  18. The CCAT 25m-class Submillimeter Telescope

    NASA Astrophysics Data System (ADS)

    Fich, Michel; and the CCAT Team

    2016-01-01

    Over cosmic time, half of the radiation emitted by stars has been absorbed by dust and subsequently re-emitted at rest-frame far-infrared to submillimeter wavelengths. A full understanding of the star formation history of the Universe thus requires observations in the submillimeter wavebands. We here give a status update on CCAT, which is envisioned to be a 25-m class submillimeter telescope that will enable a broad range of astronomical studies focused on the origins of stars, galaxies and galaxy clusters. Some of the primary science goals enabled by CCAT will be (1) a detailed measurement of the dust-obscured fraction of the cosmic star formation history back to within the first billion years of cosmic time - by resolving, for the first time, almost the entire far-infrared background light into individual sources, (2) a characterization of the physical mechanisms and energy sources that power the emission from the galaxies involved - such as stellar radiation, shocks, or active galactic nuclei - through spectroscopy, (3) tracing the cycles and components of star formation in the Milky Way and nearby galaxies over large scales at unprecedented spatial and spectral resolution, and in a wide range of different environments, and (4) probing the astrophysical processes in galaxy clusters through multi-band, high resolution studies of the Sunyaev-Zel'dovich effect. Located on a high elevation site in the Atacama Desert of northern Chile (at 5600 meter altitude), CCAT is designed to provide sensitive high angular resolution observations at submillimeter wavelengths (3.5" at 350 micron) over up to a 1 square degree field-of-view. The combination of a large aperture telescope with a precise surface (<17 micron rms wave front error) at a prime observing site, a wide field-of-view (and hence, high mapping speed) utilized through state-of-the-art, large-format cameras and sensitive, multi-object spectrometers makes CCAT an exceptionally powerful discovery instrument.

  19. The CCAT 25m-class Submillimeter Telescope

    NASA Astrophysics Data System (ADS)

    Riechers, Dominik Alexander; Stacey, Gordon; Giovanelli, Riccardo; Bertoldi, Frank; Chapman, Scott; Fich, Mike; Haynes, Martha; Herter, Terry; Murray, Norm; Schilke, Peter; Stutzki, Juergen; Zivick, Jeff

    2015-08-01

    Over cosmic time, half of the radiation emitted by stars has been absorbed by dust and subsequently re-emitted at rest-frame far-infrared to submillimeter wavelengths. A full understanding of the star formation history of the Universe thus requires observations in the submillimeter wavebands. We here give a status update on CCAT, which is envisioned to be a 25-m class submillimeter telescope that will enable a broad range of astronomical studies focused on the origins of stars, galaxies and galaxy clusters. Some of the primary science goals enabled by CCAT will be (1) a detailed measurement of the dust-obscured fraction of the cosmic star formation history back to within the first billion years of cosmic time - by resolving, for the first time, almost the entire far-infrared background light into individual sources, (2) a characterization of the physical mechanisms and energy sources that power the emission from the galaxies involved - such as stellar radiation, shocks, or active galactic nuclei - through spectroscopy, (3) tracing the cycles and components of star formation in the Milky Way and nearby galaxies over large scales at unprecedented spatial and spectral resolution, and in a wide range of different environments, and (4) probing the astrophysical processes in galaxy clusters through multi-band, high resolution studies of the Sunyaev-Zel'dovich effect. Located on a high elevation site in the Atacama Desert of northern Chile (at 5600 meter altitude), CCAT is designed to provide sensitive high angular resolution observations at submillimeter wavelengths (3.5" at 350 micron) over up to a 1 square degree field-of-view. The combination of a large aperture telescope with a precise surface (<17 micron rms wave front error) at a prime observing site, a wide field-of-view (and hence, high mapping speed) utilized through state-of-the-art, large-format cameras and sensitive, multi-object spectrometers makes CCAT an exceptionally powerful discovery instrument.

  20. The NASA/AFRL Meter Class Autonomous Telescope

    NASA Technical Reports Server (NTRS)

    Cowardin, H.; Lederer, S.; Buckalew, B.; Frith, J.; Hickson, P.; Glesne, T.; Anz-Meador, P.; Barker, E.; Stansbery, G.; Kervin, P.

    2016-01-01

    For the past decade, the NASA Orbital Debris Program Office (ODPO) has relied on using various ground-based telescopes in Chile to acquire statistical survey data as well as photometric and spectroscopic data of orbital debris in geosynchronous Earth orbit (GEO). The statistical survey data have been used to supply the Orbital Debris Engineering Model (ORDEM) v.3.0 with debris detections in GEO to better model the environment at altitudes where radar detections are limited. The data produced for the statistical survey ranged from 30 to 40 nights per year, which only accounted for 10% of the possible observing time. Data collection was restricted by ODPO resources and weather conditions. In order to improve the statistical sampling in GEO, as well as observe and sample other orbits, NASA's ODPO with support from the Air Force Research Laboratory (AFRL), has constructed a new observatory dedicated to orbital debris - the Meter Class Autonomous Telescope (MCAT) on Ascension Island. This location provides MCAT with the unique ability to access targets orbiting at an altitude of less than 1,000 km and low inclinations (< 20 deg). This orbital regime currently has little to no coverage by the U.S. Space Surveillance Network. Unlike previous ODPO optical assets, the ability to operate autonomously will allow rapid response observations of break-up events, an observing mode that was only available via radar tasking prior to MCAT's deployment. The primary goal of MCAT is to statistically characterize GEO via daily tasking files uploaded from ODPO. These tasking files define which operating mode to follow, providing the field center, rates, and/or targets to observe over the entire observing period. The system is also capable of tracking fast-moving targets in low Earth orbit (LEO), middle Earth orbit (MEO), as well as highly eccentric orbits like geostationary transfer orbits. On 25 August 2015, MCAT successfully acquired scientific first light, imaging the Bug Nebula and

  1. The Virtual Space Telescope: A New Class of Science Missions

    NASA Technical Reports Server (NTRS)

    Shah, Neerav; Calhoun, Philip

    2016-01-01

    Many science investigations proposed by GSFC require two spacecraft alignment across a long distance to form a virtual space telescope. Forming a Virtual Space telescope requires advances in Guidance, Navigation, and Control (GNC) enabling the distribution of monolithic telescopes across multiple space platforms. The capability to align multiple spacecraft to an intertial target is at a low maturity state and we present a roadmap to advance the system-level capability to be flight ready in preparation of various science applications. An engineering proof of concept, called the CANYVAL-X CubeSat MIssion is presented. CANYVAL-X's advancement will decrease risk for a potential starshade mission that would fly with WFIRST.

  2. The NASA Meter Class Autonomous Telescope: Ascension Island

    DTIC Science & Technology

    2013-09-01

    1 MODEST is a 0.6m telescope located at Cerro Tololo Interamerican Observatory (CTIO). Report Documentation Page Form...nesting sea turtles that require the darkest skies possible. This results in skies that are also ideal for an observatory . Fig. 2: An estimate of...resolution is 30 minutes taken during the night (no daytime observations). Summer (starting in December) through fall in this southern hemisphere location

  3. Photometric Reverberation Mapping using a Meter-class Telescope

    NASA Astrophysics Data System (ADS)

    Carroll, Carla June; Joner, Michael D.

    2015-01-01

    For the past several decades, mass estimates for supermassive black holes hosted by active galactic nuclei (AGNs) have been made using the reverberation mapping (RM) technique. This methodology has produced consistent results and has been used to establish several relations that link the characteristics of the host galaxy to the mass of the central black hole. Despite this success, there are less than 50 AGNs with black hole masses derived from RM. This low number is generally attributed to the difficulties in coordinating large blocks of telescope time for making the simultaneous photometric and spectroscopic observations. In addition, the spectroscopic observations generally require several months of nightly observations with moderate to large size telescopes.We have made photometric observations of several AGNs in selected filters in order to evaluate a photometric methodology for determining the lag time between the variations observed in the continuum and the response signal that is seen coming from the broad-line region (BLR) gas. This time delay represents the mean light travel time to the BLR, and is therefore a measurement of the mean BLR radius. In traditional RM campaigns, this time lag is combined with a measure of the width of the broad line to determine the velocity of the gas and then make a virial estimate of the black hole mass. We investigate results obtained using photometric time lags and a single epoch spectroscopic measurement of the line width in order to estimate the mass of the central black hole.We present results from our photometric observations of several target AGNs made with the West Mountain Observatory 0.9 m reflector during the spring and summer of 2014.This research was supported by the College of Physical and Mathematical Sciences at Brigham Young University as well as through a fellowship from the NASA Rocky Mountain Space Grant Consortium.

  4. Grazing incidence telescopes - A new class for soft X-ray and EUV spectroscopy

    NASA Technical Reports Server (NTRS)

    Hettrick, M. C.; Bowyer, S.

    1984-01-01

    A new class of grazing incidence telescopes is identified, and its advantages for stellar spectroscopy are discussed. In particular, three types of telescope geometry consisting of a primary and a secondary, both at grazing incidence, are proposed. Type I delivers a converging beam having a real focus; type II delivers a diverging beam from a virtual focus, and type III delivers a collimated beam concentrated relative to the primary aperture. The three telescope types are shown to possess unique properties which improve the efficiency and shorten the length of soft X-ray/EUV spectrographs.

  5. The Cosmology Large Angular Scale Surveyor (CLASS) Telescope Architecture

    NASA Technical Reports Server (NTRS)

    Chuss, David T.; Ali, Aamir; Amiri, Mandana; Appel, John W.; Araujo, Derek; Bennett, Charles L.; Boone, Fletcher; Chan, Manwei; Cho, Hsiao-Mei; Colazo, Felipe; Crowe, Erik; Denis, Kevin L.; Dunner, Rolando; Eimer, Joseph; Essinger-Hileman, Thomas; Gothe, Dominik; Halpern, Mark; Harrington, Kathleen; Hilton, Gene; Hinshaw, Gary F.; Huang, Caroline; Irwin, Kent; Jones, Glenn; Karakla, John; Kogut, Alan J.; Larson, David; Limon, Michele; Lowry, Lindsay; Marriage, Tobias; Mehrle, Nicholas; Stevenson, Thomas; Miller, Nathan J.; Moseley, Samuel H.; U-Yen, Kongpop; Wollack, Edward

    2014-01-01

    We describe the instrument architecture of the Johns Hopkins University-led CLASS instrument, a groundbased cosmic microwave background (CMB) polarimeter that will measure the large-scale polarization of the CMB in several frequency bands to search for evidence of inflation.

  6. A Characterization Of The GNAT SciTech STAR Class 0.5m Prototype Telescope

    NASA Astrophysics Data System (ADS)

    Barentine, J. C.; Culver, R. B.

    2002-05-01

    In 1995 the Global Network of Automated Telescopes (GNAT) acquired an option to purchase a 0.5m "STAR" class telescope, manufactured by SciTech Corporation of Forresthill, CA, contingent upon its attainment of performance specifications published by SciTech. In spite of a concerted, and protracted effort, the telescope has not yet approached the manufacturer's specifications, and has proven largely unusable for its intended purpose. In light of the difficult history of commercial development of true automated telescopes (see Sinnott 1996 and Henry 1994) it is important to understand the current state of such commercial systems. We present results of a characterization of this telescope and recommendations for how to proceed in light of its failure to attain specifications. Principle failings of the telescope can be summarized as follows: 1) the mechanical structure was inadequately designed and built, yielding large and unacceptable pointing and tracking errors, 2) the autoguider system was never successfully implemented, limiting the system to very short integrations, 3) the autofocus mechanism was never successfully implemented, resulting in periodic, unacceptable focus drifts during automatic operation, 4) the telescope control system as provided with the telescope did not work and ultimately had to be developed by an independent contractor recommended by GNAT and contracted through SciTech, and 5) the telescope optical system design did not adequately accommodate scattered light issues, yielding significant scattered light contributions to the images under certain conditions. Based on analyses of these issues, we present recommendations for improvements in this system. Support of this work has been provided by Colorado State University and GNAT. REFERENCES Sinnott, R.W. Sky And Telescope vol.91, no.6, p.38 (1996) Henry, G.W. IAPPP Communication No.57, Autumn 1994, p.57

  7. Atmospheric tomography with Rayleigh laser beacons for correction of wide fields and 30-m-class telescopes

    NASA Astrophysics Data System (ADS)

    Angel, J. Roger P.; Lloyd-Hart, Michael

    2000-07-01

    Single sodium beacons will likely be the most convenient for adaptive systems to correct 6 - 10 m class telescopes over a small field of view (the isoplanatic angle), provided reliable, powerful 589 nm lasers become available and affordable. However, when adaptive optics are applied to extended fields of view and correction of telescopes as large as 32 m diameter, it seems likely that laser beacons produced by Rayleigh scattering will be preferred. For these more demanding applications which require atmospheric tomography, Rayleigh beacons come into their own for two reasons. First, the cone effect, which causes the high turbulence to be sampled at a different scale, is no longer problematic when multiple lasers are used and height dependence is solved for explicitly. Second, the tomographic solution can make use of the beacon created by a laser pulse during all of its journey through the upper atmosphere, not just scattering from a thin layer selected by range gating. In this way a laser that costs an order of magnitude less to buy and maintain than a sodium laser of the same power can yield a brighter beacon and more information about the atmospheric turbulence. This is important because both the number and brightness of beacons or stars must increase with the number of layers included in the tomographic solution. For the same reason, tomography with natural stars is unlikely to be valuable for very large telescopes because in general the number and required brightness of each star increase with corrected field angle, while current narrow-field adaptive optics systems relying on natural stars are already very limited in sky coverage. Our method for tomography to take advantage of Rayleigh scattering over a wide range of heights uses short pulses from near diffraction-limited, ultraviolet lasers, projected from a small aperture above the telescope's secondary mirror. Each pulse subtends less than 1 arcsec at any instant as it travels up through many kilometers. An

  8. Generalized atmospheric dispersion correctors for Thirty Meter Telescope

    NASA Astrophysics Data System (ADS)

    Sutin, Brian M.

    2016-08-01

    The Thirty Meter Telescope (TMT) is unbaffled and has stability requirements tighter than the previous generation of 10- m class telescopes, leading to tougher requirements on atmospheric dispersion correctors (ADCs). Since instruments are internally baffled, ADCs may no longer shift the position of the telescope exit pupil. Designs that control pupil position are explored.

  9. Reverse and concurrent engineering applied of a high resolution equipment Berkut for 1-meter class telescopes

    NASA Astrophysics Data System (ADS)

    López, R.; Granados, R.; Farah, A.

    2014-07-01

    Several factors make observational astronomy difficult for astronomers; one of them is the atmosphere. The light that a star emits is refracted when it goes through the earth's atmosphere; the result of this is that the image of a punctual star is not what the physics would lead us to expect. At the Instituto de Astronomia of the Universidad Nacional Autonoma de México (IA-UNAM) an instrument has been developed called "Berkut", which uses a high resolution technique to improve these effects and obtain interesting and valuable scientific studies. In this paper we present the mechanical reengineering and acceptance test of Berkut. This instrument was design for taking images of high resolution. Essentially, it is composed by a set basic optics which is aligned and in focus with a 1- meter class telescope. It has its own electronic components for controlling remotely a filter wheel; that allows the exchange of the filters according to the requirements of the observer, a couple of objectives mounted in a translation stage, and a CCD camera for acquiring several images per second that are used in the speckle interferometry technique. A project like Berkut needs to be multidisciplinary; astronomy, engineering, optics, mechanics, electronics, and image processing are some of the areas of knowledge used. Berkut will be used in the telescope of the Observatorio Astronomico Nacional in Tonantzintla, located in the state of Puebla, Mexico, but it can be used in any telescope 1 meter class. It is pretended to build another Berkuts for being used simultaneously in different telescopes, so it is important to keep the costs as low as possible. With this instrument we pretend to confirm the Hipparcos catalogue of binary stars besides finding exoplanets.

  10. Deploying the NASA Meter Class Autonomous Telescope (MCAT) on Ascension Island

    NASA Technical Reports Server (NTRS)

    Lederer, S. M.; Pace, L.; Hickson, P.; Cowardin, H. M.; Frith, J.; Buckalew, B.; Glesne, T.; Maeda, R.; Douglas, D.; Nishimoto, D.

    2015-01-01

    NASA has successfully constructed the 1.3m Meter Class Autonomous Telescope (MCAT) facility on Ascension Island in the South Atlantic Ocean. MCAT is an optical telescope designed specifically to collect ground-based data for the statistical characterization of orbital debris ranging from Low Earth Orbit (LEO) through Middle Earth Orbits (MEO) and beyond to Geo Transfer and Geosynchronous Orbits (GTO/GEO). The location of Ascension Island has two distinct advantages. First, the near-equatorial location fills a significant longitudinal gap in the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) network of telescopes, and second, it allows access to objects in Low Inclination Low-Earth Orbits (LILO). The MCAT facility will be controlled by a sophisticated software suite that operates the dome and telescope, assesses sky and weather conditions, conducts all necessary calibrations, defines an observing strategy (as dictated by weather, sky conditions and the observing plan for the night), and carries out the observations. It then reduces the collected data via four primary observing modes ranging from tracking previously cataloged objects to conducting general surveys for detecting uncorrelated debris. Nightly observing plans, as well as the resulting text file of reduced data, will be transferred to and from Ascension, respectively, via a satellite connection. Post-processing occurs at NASA Johnson Space Center. Construction began in September, 2014 with dome and telescope installation occurring in April through early June, 2015. First light was achieved in June, 2015. Acceptance testing, full commissioning, and calibration of this soon-to-be fully autonomous system commenced in summer 2015. The initial characterization of the system from these tests is presented herein.

  11. Deploying the NASA Meter Class Autonomous Telescope (MCAT) on Ascension Island

    NASA Astrophysics Data System (ADS)

    Lederer, S.; Pace, L. F.; Hickson, P.; Glesne, T.; Cowardin, H. M.; Frith, J. M.; Buckalew, B.; Maeda, R.; Douglas, D.; Nishimoto, D.

    NASA has successfully constructed the 1.3m Meter Class Autonomous Telescope (MCAT) facility on Ascension Island in the South Atlantic Ocean. MCAT is an optical telescope designed specifically to collect ground-based data for the statistical characterization of orbital debris ranging from Low Earth Orbit (LEO) through Middle Earth Orbits (MEO) and beyond to Geo Transfer and Geosynchronous Orbits (GTO/GEO). The location of Ascension Island has two distinct advantages. First, the near-equatorial location fills a significant longitudinal gap in the Ground-based Electro-Optical Deep Space Surveillance (GEODSS) network of telescopes, and second, it allows access to objects in Low Inclination Low-Earth Orbits (LILO). The MCAT facility will be controlled by a sophisticated software suite that operates the dome and telescope, assesses sky and weather conditions, conducts all necessary calibrations, defines an observing strategy (as dictated by weather, sky conditions, and the observing plan for the night), and carries out the observations. It then reduces the collected data via four primary observing modes ranging from tracking previously cataloged objects to conducting general surveys for detecting uncorrelated debris. Nightly observing plans, as well as the resulting text file of reduced data, will be transferred to and from Ascension, respectively, via a satellite connection. Post-processing occurs at NASA Johnson Space Center. Construction began in September, 2014 with dome and telescope installation occurring in April through early June, 2015. First light was achieved in June, 2015. Acceptance testing, full commissioning, and calibration of this soon-to-be fully autonomous system commenced in summer 2015. The initial characterization of the system from these tests is presented herein.

  12. Tolerance analysis during the optical design of 4m class optical telescope

    NASA Astrophysics Data System (ADS)

    Singh, S. K.; Muthu Marriappan, C.; Kumar, Brijesh; Gupta, K. G.

    The detailed tolerance analysis has been carried out for the proposed 4 m class (RC) Devasthal Optical Telescope (DOT) using ZEMAX - EE to study system performance and meet the image quality criteria. The latter requires encircled energy (E90) to be concentrated within 0.6 arcsec diameter. The spot diagrams and E80 have been studied with various values of tilt, decenter, surface irregularity and temperature, while the polarization studies are under ess. It has been found that after applying the system tolerances the rms change in the system performance is within the range 4 to 6%.

  13. What astronomy with meter-class telescopes? Sharing experience with the next-door observatory

    NASA Astrophysics Data System (ADS)

    Iliev, I.

    2014-03-01

    When asking what astronomical observations are most relevant to meter-class telescopes we will get a lot of answers - usually as many as astronomers have been interviewed. The aim of our review is to give some useful hints having observational practices and scientific projects carried out at the Rozhen National Observatory as examples. We discuss in brief the topics concerning observations of comets and asteroids - observed both photometrically and positionally, exo-planets - newly found and already known transits, optical monitoring of large variety of variable stars and stellar systems on different time-scales - from short term to very long term, hunting for novae in our Galaxy and in nearby galaxies, supernovae search and monitoring, active galactic nuclei and their photometric behavior.

  14. Exploring the unified class of Type II Supernovae with the Las Cumbres Observatory Global Telescope Network

    NASA Astrophysics Data System (ADS)

    Valenti, Stefano; Howell, Dale Andrew; Sand, David J.; Arcavi, Iair; Hosseinzadeh, Griffin; McCully, Curtis

    2015-01-01

    Traditionally Type II supernovae (SNe) have been separated into two distinct classes based on the shape of their light curves after peak: Type II plateau (IIP) and Type II linear (IIL) SNe. Recent works suggest that Type II SNe form a continuum of objects from a single progenitor system. Here we present data for a set of Type II SNe collected with the Las Cumbres Observatory Global Telescope (LCOGT) Network and observed simultaneously with UVOT-Swift. In the growing sample of Type II SNe, we search for clear evidence to distinguish the two classes. SNe IIL show a similar drop at the end of their short steep plateau that resemble the drop visible in SNe IIP. We show that also at early phase SNe IIP and IIL are similar both in the UV and in the optical. Our analysis is consistent with the scenario that SNe IIP and IIL come from similar progenitors but with SN IIL progenitors having been stripped of their hydrogen envelope before explosion. While SNe IIL are on average more luminous than SNe IIP, we show that they both produce a comparable amount of nickel.

  15. Orbital Debris Detection and Tracking Strategies for the NASA/AFRL Meter Class Autonomous Telescope (MCAT)

    NASA Technical Reports Server (NTRS)

    Mulrooney, M.; Hickson, P.; Stansbery, Eugene G.

    2010-01-01

    MCAT (Meter-Class Autonomous Telescope) is a 1.3m f/4 Ritchey-Chr tien on a double horseshoe equatorial mount that will be deployed in early 2011 to the western pacific island of Legan in the Kwajalein Atoll to perform orbital debris observations. MCAT will be capable of tracking earth orbital objects at all inclinations and at altitudes from 200 km to geosynchronous. MCAT s primary objective is the detection of new orbital debris in both low-inclination low-earth orbits (LEO) and at geosynchronous earth orbit (GEO). MCAT was thus designed with a fast focal ratio and a large unvignetted image circle able to accommodate a detector sized to yield a large field of view. The selected primary detector is a close-cycle cooled 4Kx4K 15um pixel CCD camera that yields a 0.9 degree diagonal field. For orbital debris detection in widely spaced angular rate regimes, the camera must offer low read-noise performance over a wide range of framing rates. MCAT s 4-port camera operates from 100 kHz to 1.5 MHz per port at 2 e- and 10 e- read noise respectively. This enables low-noise multi-second exposures for GEO observations as well as rapid (several frames per second) exposures for LEO. GEO observations will be performed using a counter-sidereal time delay integration (TDI) technique which NASA has used successfully in the past. For MCAT the GEO survey, detection, and follow-up prediction algorithms will be automated. These algorithms will be detailed herein. For LEO observations two methods will be employed. The first, Orbit Survey Mode (OSM), will scan specific orbital inclination and altitude regimes, detect new orbital debris objects against trailed background stars, and adjust the telescope track to follow the detected object. The second, Stare and Chase Mode (SCM), will perform a stare, then detect and track objects that enter the field of view which satisfy specific rate and brightness criteria. As with GEO, the LEO operational modes will be fully automated and will be

  16. Optomecatronic design and integration of a high resolution equipment Berkut to the 1-meter class telescopes

    NASA Astrophysics Data System (ADS)

    Granados, R.; López, R.; Farah, Alejandro

    2014-07-01

    It is proposed the development and implementation of a High Speed Resolution Camera instrument. The basic principle of this technique is to take several pictures of short exposure using different filters of an astronomical object of interest . These images are subsequently processed using specialized software to remove aberrations from atmosphere and from the instrument itself such as blur and scintillation among others. In this paper are described electronic and control systems implemented for BERKUT instrument based on FPGA (Field Programmable Gate Array) generated with VHDL description. An UART communication, using serial protocol, is used with a friendly User Interface providing an easy way for the astronomer to choose between different lenses and different filters for capturing the images. All the movements are produced by stepper motors that are driven by a circuit that powers all the electronics. The camera and the lenses are placed into a linear positioner with the help of a stepper motor which give us repeatable movements for positioning these optical components. Besides it is planned to integrate in the same system a pipeline for image data reduction to have one sturdy system that could fulfill any astronomer needs in the usage of this technique. With this instrument we pretend to confirm the Hipparcos catalogue of binary stars besides finding exoplanets. This technique requires more simple optical equipment and it is less sensitive to environmental noise, making it cheaper and provides good quality and great resolution images for scientific purposes. This equipment will be installed on different 1-m class telescopes in Mexico1 and probably other countries which makes it a wide application instrument.

  17. Correlation tracking study for meter-class solar telescope on space shuttle. [solar granulation

    NASA Technical Reports Server (NTRS)

    Smithson, R. C.; Tarbell, T. D.

    1977-01-01

    The theory and expected performance level of correlation trackers used to control the pointing of a solar telescope in space using white light granulation as a target were studied. Three specific trackers were modeled and their performance levels predicted for telescopes of various apertures. The performance of the computer model trackers on computer enhanced granulation photographs was evaluated. Parametric equations for predicting tracker performance are presented.

  18. Simulation and analysis of laser guide star adaptive optics systems for the eight to ten meter class telescopes

    SciTech Connect

    Gavel, D.T.; Olivier, S.S.

    1994-03-01

    This paper discusses the design and analysis of laser-guided adaptive optic systems for the large, 8--10 meter class telescopes. We describe a technique for calculating the expected modulation transfer function and the point spread function for a closed loop adaptive optics system, parameterized by the degree of correction and the seeing conditions. The results agree closely with simulations and experimental data, and validate well known scaling law models even at low order correction. Scaling law.model analysis of a proposed adaptive optics system at the Keck telescope leads to the conclusion that a single laser guide star beacon will be adequate for diffraction limited imaging at wavelengths between 1 and 3 am with reasonable coverage of the sky. Cone anisoplanatism will dominate wavefront correction error at the visible wavelengths unless multiple laser guide stars are used.

  19. Design, motivation, and on-sky tests of an efficient fiber coupling unit for 1-meter class telescopes

    NASA Astrophysics Data System (ADS)

    Bottom, Michael; Muirhead, Philip S.; Swift, Jonathan J.; Zhao, Ming; Gardner, Paul; Plavchan, Peter P.; Riddle, Reed L.; Herzig, Erich; Johnson, John A.; Wright, Jason T.; McCrady, Nate; Wittenmyer, Robert A.

    2014-08-01

    We present the science motivation, design, and on-sky test data of a high-throughput fiber coupling unit suitable for automated 1-meter class telescopes. The optical and mechanical design of the fiber coupling is detailed and we describe a flexible controller software designed specifically for this unit. The system performance is characterized with a set of numerical simulations, and we present on-sky results that validate the performance of the controller and the expected throughput of the fiber coupling. This unit was designed specifically for the MINERVA array, a robotic observatory consisting of multiple 0.7 m telescopes linked to a single high-resolution stabilized spectrograph for the purpose of exoplanet discovery using high-cadence radial velocimetry. However, this unit could easily be used for general astronomical purposes requiring fiber coupling or precise guiding.

  20. Plans for the Meter Class Autonomous Telescope and Potential Coordinated Measurements with Kwajalein Radars

    NASA Technical Reports Server (NTRS)

    Stansberry, Gene; Kervin, Paul; Mulrooney, Mark

    2010-01-01

    The National Aeronautics and Space Administration's (NASA) Orbital Debris Program Office is teaming with the US Air Force Research Laboratory's (AFRL) Maui Optical Site to deploy a moderate field-of-view, 1.3 m aperture, optical telescope for orbital debris applications. The telescope will be located on the island of Legan in the Kwajalein Atoll and is scheduled for completion in the Spring of 2011. The telescope is intended to sample both low inclination/high eccentricity orbits and near geosynchronous orbits. The telescope will have a 1 deg diagonal field-of-view on a 4K x 4K CCD. The telescope is expected to be able to detect 10-cm diameter debris at geosynchronous altitudes (5 sec exposure assuming a spherical specular phase function w/ albedo =0.13). Once operational, the telescope has the potential of conducting simultaneous observations with radars operated by the US Army at Kwajalein Atoll (USAKA) and located on the island of Roi-Namur, approximately 55 km to the north of Legan. Four radars, representing 6 frequency bands, are available for use: ALTAIR (ARPA-Long Range Tracking and Instrumentation Radar) operating at VHF & UHF, TRADEX (Target Resolution and Discrimination Experiment) operating at L-band and S-band, ALCOR (ARPA-Lincoln C-band Observables Radar) operating at S-band, and MMW (Millimeter Wave) Radar operating at Ka-band. Also potentially available is the X-band GBRP (Ground Based Radar-Prototype located 25 km to the southeast of Legan on the main island of Kwajalein.

  1. Optical Positions of ICRF Sources from CTIO 1.0M Data

    DTIC Science & Technology

    2015-01-01

    ABSTRACT As part of the USNO radio-optical reference frame link project, data were taken with the CTIO 1.0 m telescope in 2009. First position...ABSTRACT As part of the USNO radio-optical reference frame link project, data were taken with the CTIO 1.0 m telescope in 2009. First position...Yale 1.0 meter telescope and Y4K camera which were used for this study. TABLE 1. INSTRUMENT PROPERTIES aperture 1000 mm focal ratio f/10 Cass. filters

  2. Structural design of 3m class ground based telescope elevation ring

    NASA Astrophysics Data System (ADS)

    Tan, Yufeng; Wang, Jihong; Ren, Ge; Xie, Zongliang; Zhu, Fuyin; Jiang, Chuan

    2016-10-01

    In order to improve the dynamic stiffness of telescope mount, the accuracy of aiming and stability of optical system, a topology optimization method based on the theory of variable density and taking maximum stiffness as objective function is studied. In the topology optimization analysis of elevation ring, one of the most important members of the telescope mount, two kinds of structural are designed: one is a traditional plate welding structure and the other is a combination of plate welding and truss welding. Furthermore, the stiffness and modal performance of the elevation ring in different performances are analyzed and compared. The results show that in meeting the strength and stiffness of the premise, the mass of elevation ring with plate welding and truss welding is 7.00T and the moment of inertia is 11.94 t•m2. What`s more, the total deformation in the horizontal direction and the zenith direction are 6.70μm and 55.86μm, respectively; the stress is within stress range of material's promise; the modal is 105.9Hz.Compared with the traditional structural with plate welding, this new structural design approached to ensure the dynamic stiffness while effectively reducing its own weight with reduction rate 10.7% and moments of inertia with reduction rate 12.3%. This new structural of plate welding and truss welding has obvious advantages in lightweight design. This new design method based on topology optimization will provide efficient help to later components design of the telescope mount.

  3. Stellar Archaeology and Galaxy Genesis: The Need for Large Area Multi-Object Spectrograph on 8 m-Class Telescopes

    NASA Astrophysics Data System (ADS)

    Irwin, Mike J.; Lewis, Geraint F.

    The origin and evolution of galaxies like the Milky Way and M31 remain among the key questions in astrophysics. The galaxies we see today in and around the Local Group are representatives of the general field population of the Universe and have been evolving for the majority of cosmic time. As our nearest neighbour systems they can be studied in far more detail than their distant counterparts and hence provide our best hope for understanding star formation and prototypical galaxy evolution over the lifetime of the Universe [K. Freeman, J. Bland-Hawthorn in Annu. Rev. Astron. Astrophys. 40, 487 (2002)]. Significant observational progress has been made, but we are still a long way from understanding galaxy genesis. To unravel this formative epoch, detailed large area multi-object spectroscopy of spatial, kinematic and chemical structures on 8 m-class telescopes are required, to provide the link between local near-field cosmology and predictions from the high-redshift Universe.

  4. Why systems engineering on telescopes?

    NASA Astrophysics Data System (ADS)

    Swart, Gerhard P.; Meiring, Jacobus G.

    2003-02-01

    Although Systems Engineering has been widely applied to the defence industry, many other projects are unaware of its potential benefits when correctly applied, assuming that it is an expensive luxury. It seems that except in a few instances, telescope projects are no exception, prompting the writing of this paper. The authors postulate that classical Systems Engineering can and should be tailored, and then applied to telescope projects, leading to cost, schedule and technical benefits. This paper explores the essence of Systems Engineering and how it can be applied to any complex development project. The authors cite real-world Systems Engineering examples from the Southern African Large Telescope (SALT). The SALT project is the development and construction of a 10m-class telescope at the price of a 4m telescope. Although SALT resembles the groundbreaking Hobby-Eberly Telescope (HET) in Texas, the project team are attempting several challenging changes to the original design, requiring a focussed engineering approach and discernment in the definition of the telescope requirements. Following a tailored Systems Engineering approach on this project has already enhanced the quality of decisions made, improved the fidelity of contractual specifications for subsystems, and established criteria testing their performance. Systems Engineering, as applied on SALT, is a structured development process, where requirements are formally defined before the award of subsystem developmental contracts. During this process conceptual design, modeling and prototyping are performed to ensure that the requirements were realistic and accurate. Design reviews are held where the designs are checked for compliance with the requirements. Supplier factory and on-site testing are followed by integrated telescope testing, to verify system performance against the specifications. Although the SALT project is still far from completion, the authors are confident that the present benefits from

  5. Operational optical turbulence forecast for the service mode of top-class ground based telescopes

    NASA Astrophysics Data System (ADS)

    Masciadri, Elena; Lascaux, Franck; Turchi, Alessio; Fini, Luca

    2016-07-01

    In this contribution we present the most relevant results obtained in the context of a feasibility study (MOSE) undertaken for ESO. The principal aim of the project was to quantify the performances of an atmospherical non-hydrostatical mesoscale model (Astro-Meso-NH code) in forecasting all the main atmospherical parameters relevant for the ground-based astronomical observations and the optical turbulence (CN2 and associated integrated astroclimatic parameters) above Cerro Paranal (site of the VLT) and Cerro Armazones (site of the E-ELT). A detailed analysis on the score of success of the predictive capacities of the system have been carried out for all the astroclimatic as well as for the atmospherical parameters. Considering the excellent results that we obtained, this study proved the opportunity to implement on these two sites an automatic system to be run nightly in an operational configuration to support the scheduling of scientific programs as well as of astronomical facilities (particularly those supported by AO systems) of the VLT and the E-ELT. At the end of 2016 a new project for the implementation of a demonstrator of an operational system to be run on the two ESO's sites will start. The fact that the system can be run simultaneously on the two sites is an ancillary appealing feature of the system. Our team is also responsible for the implementation of a similar automatic system at Mt.Graham, site of the LBT (ALTA Project). Our system/method will permit therefore to make a step ahead in the framework of the Service Mode for new generation telescopes. Among the most exciting achieved results we cite the fact that we proved to be able to forecast CN2 profiles with a vertical resolution as high as 150 m. Such a feature is particularly crucial for all WFAO systems that require such detailed information on the OT vertical stratification on the whole 20 km above the ground. This important achievement tells us that all the WFAO systems can rely on automatic

  6. Adaptive Optics Imaging of the CLASS Gravitational Lens System B1359+154 with the Canada-France-Hawaii Telescope.

    PubMed

    Rusin; Hall; Nichol; Marlow; Richards; Myers

    2000-04-20

    We present adaptive optics imaging of the CLASS gravitational lens system B1359+154 obtained with the Canada-France-Hawaii Telescope (CFHT) in the infrared K band. The observations show at least three brightness peaks within the ring of lensed images, which we identify as emission from multiple lensing galaxies. The results confirm the suspected compound nature of the lens, as deduced from preliminary mass modeling. The detection of several additional nearby galaxies suggests that B1359+154 is lensed by the compact core of a small galaxy group. We attempted to produce an updated lens model based on the CFHT observations and new 5 GHz radio data obtained with the MERLIN array, but there are too few constraints to construct a realistic model at this time. The uncertainties inherent with modeling compound lenses make B1359+154 a challenging target for Hubble constant determination through the measurement of differential time delays. However, time delays will offer additional constraints to help pin down the mass model. This lens system therefore presents a unique opportunity to directly measure the mass distribution of a galaxy group at intermediate redshift.

  7. SNAP Telescope

    NASA Astrophysics Data System (ADS)

    Lampton, Michael L.; Akerlof, Carl W.; Aldering, Greg; Amanullah, R.; Astier, Pierre; Barrelet, E.; Bebek, Christopher; Bergstrom, Lars; Bercovitz, John; Bernstein, G.; Bester, Manfred; Bonissent, Alain; Bower, C. R.; Carithers, William C., Jr.; Commins, Eugene D.; Day, C.; Deustua, Susana E.; DiGennaro, Richard S.; Ealet, Anne; Ellis, Richard S.; Eriksson, Mikael; Fruchter, Andrew; Genat, Jean-Francois; Goldhaber, Gerson; Goobar, Ariel; Groom, Donald E.; Harris, Stewart E.; Harvey, Peter R.; Heetderks, Henry D.; Holland, Steven E.; Huterer, Dragan; Karcher, Armin; Kim, Alex G.; Kolbe, William F.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, Michael E.; Levin, Daniel S.; Linder, Eric V.; Loken, Stewart C.; Malina, Roger; Massey, R.; McKay, Timothy; McKee, Shawn P.; Miquel, Ramon; Mortsell, E.; Mostek, N.; Mufson, Stuart; Musser, J. A.; Nugent, Peter E.; Oluseyi, Hakeem M.; Pain, Reynald; Palaio, Nicholas P.; Pankow, David H.; Perlmutter, Saul; Pratt, R.; Prieto, Eric; Refregier, Alexandre; Rhodes, J.; Robinson, Kem E.; Roe, N.; Sholl, Michael; Schubnell, Michael S.; Smadja, G.; Smoot, George F.; Spadafora, A.; Tarle, Gregory; Tomasch, Andrew D.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, Guobin

    2002-12-01

    The SuperNova/Acceleration Probe (SNAP) mission will require a two-meter class telescope delivering diffraction limited images spanning a one degree field in the visible and near infrared wavelength regime. This requirement, equivalent to nearly one billion pixel resolution, places stringent demands on its optical system in terms of field flatness, image quality, and freedom from chromatic aberration. We discuss the advantages of annular-field three-mirror anastigmat (TMA) telescopes for applications such as SNAP, and describe the features of the specific optical configuration that we have baselined for the SNAP mission. We discuss the mechanical design and choice of materials for the telescope. Then we present detailed ray traces and diffraction calculations for our baseline optical design. We briefly discuss stray light and tolerance issues, and present a preliminary wavefront error budget for the SNAP Telescope. We conclude by describing some of tasks to be carried out during the upcoming SNAP research and development phase.

  8. SNAP telescope

    SciTech Connect

    Lampton, Michael L.; Akerlof, C.W.; Aldering, G.; Amanullah, R.; Astier, P.; Barrelet, E.; Bebek, C.; Bergstrom, L.; Bercovitz, J.; Bernstein, G.; Bester, M.; Bonissent, A.; Bower, C.; Carithers Jr., W.C.; Commins, E.D.; Day, C.; Deustua, S.E.; DiGennaro, R.; Ealet, A.; Ellis,R.S.; Eriksson, M.; Fruchter, A.; Genat, J.-F.; Goldhaber, G.; Goobar,A.; Groom, D.; Harris, S.E.; Harvey, P.R.; Heetderks, H.D.; Holland,S.E.; Huterer, D.; Karcher, A.; Kim, A.G.; Kolbe, W.; Krieger, B.; Lafever, R.; Lamoureux, J.; Levi, M.E.; Levin, D.S.; Linder, E.V.; Loken,S.C.; Malina, R.; Massey, R.; McKay, T.; McKee, S.P.; Miquel, R.; Mortsell, E.; Mostek, N.; Mufson, S.; Musser, J.; Nugent, P.; Oluseyi,H.; Pain, R.; Palaio, N.; Pankow, D.; Perlmutter, S.; Pratt, R.; Prieto,E.; Refregier, A.; Rhodes, J.; Robinson, K.; Roe, N.; Sholl, M.; Schubnell, M.; Smadja, G.; Smoot, G.; Spadafora, A.; Tarle, G.; Tomasch,A.; von der Lippe, H.; Vincent, R.; Walder, J.-P.; Wang, G.; Wang, G.

    2002-07-29

    The SuperNova/Acceleration Probe (SNAP) mission will require a two-meter class telescope delivering diffraction limited images spanning a one degree field in the visible and near infrared wavelength regime. This requirement, equivalent to nearly one billion pixel resolution, places stringent demands on its optical system in terms of field flatness, image quality, and freedom from chromatic aberration. We discuss the advantages of annular-field three-mirror anastigmat (TMA) telescopes for applications such as SNAP, and describe the features of the specific optical configuration that we have baselined for the SNAP mission. We discuss the mechanical design and choice of materials for the telescope. Then we present detailed ray traces and diffraction calculations for our baseline optical design. We briefly discuss stray light and tolerance issues, and present a preliminary wavefront error budget for the SNAP Telescope. We conclude by describing some of tasks to be carried out during the upcoming SNAP research and development phase.

  9. Design and performance of the Douglas Mawson telescope

    NASA Astrophysics Data System (ADS)

    Lawrence, Jon S.; Ashley, Michael C. B.; Burton, Michael G.; Storey, John W. V.

    2002-12-01

    The Douglas Mawson Telescope (DMT) is a proposed 2 m telescope to be situated on the Antarctic plateau. The proposal comes from Australia, and invites participation by other nations, especially those already active in Antarctic astronomy; such as Italy, France and the United States. The DMT will be equipped with instrumentation to perform wide-field imaging from the near to far infrared. Results from an extensive site testing campaign over the last decade indicates that an Antarctic infrared telescope can be one to two orders of magnitude more sensitive than any other ground based telescope of the same size. The DMT will be an important tool for astrophysical research. It will also be beneficial as a technological test bed for future large (8-10 m class) Antarctic telescopes and interferometers, and for space-based telescopes. This paper analyses the performance of the DMT in terms of the achievable resolution, field-of-view, sensitivity and survey depth and compares it to a similar sized telescope located with the characteristic mid-latitude atmosphere of Mauna Kea.

  10. Design solutions for dome and main structure (mount) of giant telescopes

    NASA Astrophysics Data System (ADS)

    Murga, Gaizka; Bilbao, Armando; de Bilbao, Lander; Lorentz, Thomas E.

    2016-07-01

    During the last recent years, designs for several giant telescopes ranging from 20 to 40m in diameter are being developed: European Extremely Large Telescope Telescope (TMT). (E-ELT), Giant Magellan Telescope (GMT) and Thirty Meter It is evident that simple direct up-scaling of solutions that were more or less successful in the 8 to 10m class telescopes can not lead to viable designs for the future giant telescopes. New solutions are required to provide adequate load sharing, to cope with the large-scale derived deflections and to provide the required compliance, or to respond to structure-mechanism control interaction issues, among others. From IDOM experience in the development of the Dome and Main Structure of the European Extremely Large Telescope and our participation in some other giant telescopes, this paper reviews several design approaches for the main mechanisms and key structural parts of enclosures and mounts/main structures for giant telescopes, analyzing pros and cons of the different alternatives and outlining the preferred design schemes. The assessment is carried out mainly from a technical and performance-based angle but it also considers specific logistical issues for the assembly of these large telescopes in remote and space-limited areas, together with cost and schedule related issues.

  11. AFTERGLOW OBSERVATIONS OF FERMI LARGE AREA TELESCOPE GAMMA-RAY BURSTS AND THE EMERGING CLASS OF HYPER-ENERGETIC EVENTS

    SciTech Connect

    Cenko, S. B.; Butler, N. R.; Cobb, B. E.; Cucchiara, A.; Bloom, J. S.; Perley, D. A.; Filippenko, A. V.; Frail, D. A.; Harrison, F. A.; Haislip, J. B.; Reichart, D. E.; Ivarsen, K. M.; LaCluyze, A. P.; Berger, E.; Chandra, P.; Fox, D. B.; Prochaska, J. X.; Kasliwal, M. M.; Kulkarni, S. R.

    2011-05-01

    We present broadband (radio, optical, and X-ray) light curves and spectra of the afterglows of four long-duration gamma-ray bursts (GRBs; GRBs 090323, 090328, 090902B, and 090926A) detected by the Gamma-Ray Burst Monitor and Large Area Telescope (LAT) instruments on the Fermi satellite. With its wide spectral bandpass, extending to GeV energies, Fermi is sensitive to GRBs with very large isotropic energy releases (10{sup 54} erg). Although rare, these events are particularly important for testing GRB central-engine models. When combined with spectroscopic redshifts, our afterglow data for these four events are able to constrain jet collimation angles, the density structure of the circumburst medium, and both the true radiated energy release and the kinetic energy of the outflows. In agreement with our earlier work, we find that the relativistic energy budget of at least one of these events (GRB 090926A) exceeds the canonical value of 10{sup 51} erg by an order of magnitude. Such energies pose a severe challenge for models in which the GRB is powered by a magnetar or a neutrino-driven collapsar, but remain compatible with theoretical expectations for magnetohydrodynamical collapsar models (e.g., the Blandford-Znajek mechanism). Our jet opening angles ({theta}) are similar to those found for pre-Fermi GRBs, but the large initial Lorentz factors ({Gamma}{sub 0}) inferred from the detection of GeV photons imply {theta}{Gamma}{sub 0} {approx} 70-90, values which are above those predicted in magnetohydrodynamic models of jet acceleration. Finally, we find that these Fermi-LAT events preferentially occur in a low-density circumburst environment, and we speculate that this might result from the lower mass-loss rates of their lower-metallicity progenitor stars. Future studies of Fermi-LAT afterglows at radio wavelengths with the order-of-magnitude improvement in sensitivity offered by the Extended Very Large Array should definitively establish the relativistic energy

  12. ATST telescope mount: telescope of machine tool

    NASA Astrophysics Data System (ADS)

    Jeffers, Paul; Stolz, Günter; Bonomi, Giovanni; Dreyer, Oliver; Kärcher, Hans

    2012-09-01

    The Advanced Technology Solar Telescope (ATST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope mount has proportions similar to an 8 meter class telescope. The technology normally used in this class of telescope is well understood in the telescope community and has been successfully implemented in numerous projects. The world of large machine tools has developed in a separate realm with similar levels of performance requirement but different boundary conditions. In addition the competitive nature of private industry has encouraged development and usage of more cost effective solutions both in initial capital cost and thru-life operating cost. Telescope mounts move relatively slowly with requirements for high stability under external environmental influences such as wind buffeting. Large machine tools operate under high speed requirements coupled with high application of force through the machine but with little or no external environmental influences. The benefits of these parallel development paths and the ATST system requirements are being combined in the ATST Telescope Mount Assembly (TMA). The process of balancing the system requirements with new technologies is based on the experience of the ATST project team, Ingersoll Machine Tools who are the main contractor for the TMA and MT Mechatronics who are their design subcontractors. This paper highlights a number of these proven technologies from the commercially driven machine tool world that are being introduced to the TMA design. Also the challenges of integrating and ensuring that the differences in application requirements are accounted for in the design are discussed.

  13. Demonstration of a 10-m Solar Sail System

    NASA Technical Reports Server (NTRS)

    Murphy, David M.; Macy, Brian D.; Gaspar, James L.

    2004-01-01

    The NASA In-Space Propulsion (ISP) program has been sponsoring system design development and hardware demonstration activities of solar sail technology over the past 16 months. Efforts to validate by test a moderate-scale (10-m) 1/4 symmetry ground demonstration sail system are nearly complete. Results of testing and analytical model validation of component and assembly functional, strength, stiffness, shape, and dynamic behavior are discussed.

  14. Space Telescope.

    ERIC Educational Resources Information Center

    National Aeronautics and Space Administration, Huntsville, AL. George C. Marshall Space Flight Center.

    This pamphlet describes the Space Telescope, an unmanned multi-purpose telescope observatory planned for launch into orbit by the Space Shuttle in the 1980s. The unique capabilities of this telescope are detailed, the major elements of the telescope are described, and its proposed mission operations are outlined. (CS)

  15. Space Infrared Telescope Facility (SIRTF) telescope overview

    NASA Technical Reports Server (NTRS)

    Schember, Helene; Manhart, Paul; Guiar, Cecilia; Stevens, James H.

    1991-01-01

    The Space Infrared Telescope Facility (SIRTF) will be the first true infrared observatory in space, building upon the technical and scientific experience gained through its two NASA survey-oriented predecessors: the Infrared Astronomical Satellite and the Cosmic Background Explorer. During its minimum five year lifetime, the SIRTF will perform pointed scientific observations at wavelengths from 1.8 to 1200 microns with an increase in sensitivity over previous missions of several orders of magnitude. This paper discusses a candidate design for the SIRTF telescope, encompassing optics, cryostat, and instrument accommodation, which has been undertaken to provide a fulcrum for the development of functional requirements, interface definition, risk assessment and cost. The telescope optics employ a baffled Ritchey-Chretien Cassegrain system with a 1-m class primary mirror, an active secondary mirror, and a stationary facetted tertiary mirror. The optics are embedded in a large superfluid He cryostat designed to maintain the entire telescope-instrument system at temperatures below 3 K.

  16. Heinrich Hertz Telescope

    NASA Astrophysics Data System (ADS)

    Baars, Jacob W.; Martin, Robert N.

    1998-07-01

    The Heinrich Hertz Telescope is a radio telescope dedicated to the observation of submillimeter wavelength radiation from celestial sources. It is a Cassegrain telescope with a diameter of 10 m and a reflector accuracy of about 17 micrometer, yielding an excellent performance at 350 micrometer, the shortest wavelength transmitted through the atmosphere. The reflector panels and the backup structure employ carbon-fiber reinforced plastic as basic material to achieve a lightweight, stiff construction with a very small coefficient of thermal expansion. This enables us to maintain full performance of the telescope in day time under solar illumination of the structure. In this paper, we describe the structural and material characteristics of the telescope. We also describe the holographic method which enables a measurement and setting of the reflector panels to an accuracy of 10 micrometer. The telescope is located on Mt. Graham in Eastern Arizona at an altitude of 3250 m, providing good submillimeter observing conditions, especially in the winter months. This is a collaborative effort of the Max-Planck- Institut fur Radioastronomie, Bonn, Germany and Steward Observatory, University of Arizona, Tucson, AZ.

  17. 10m/500 Mbps WDM visible light communication systems.

    PubMed

    Lin, Wen-Yi; Chen, Chia-Yi; Lu, Hai-Han; Chang, Ching-Hung; Lin, Ying-Pyng; Lin, Huang-Chang; Wu, Hsiao-Wen

    2012-04-23

    A wavelength-division-multiplexing (WDM) visible light communiction (VLC) system employing red and green laser pointer lasers (LPLs) with directly modulating data signals is proposed and experimentally demonstrated. With the assistance of preamplifier and adaptive filter at the receiving sites, low bit error rate (BER) at 10 m/500 Mbps operation is obtained for each wavelength. The use of preamplifier and adaptive filter offer significant improvements for free-space transmission performance. Improved performance of BER of <10(-9), as well as better and clear eye diagram were achieved in our proposed WDM VLC systems. LPL features create a new category of good performance with high-speed data rate, long transmission length (>5m), as well as easy handling and installation. This proposed WDM VLC system reveals a prominent one to present its advancement in simplicity and convenience to be installed.

  18. Space Telescopes

    NASA Technical Reports Server (NTRS)

    Clampin, Mark; Flanagan, Kathryn A.

    2012-01-01

    Space telescopes have been a dominant force in astrophysics and astronomy over the last two decades. As Lyman Spitzer predicted in 1946, space telescopes have opened up much of the electromagnetic spectrum to astronomers, and provided the opportunity to exploit the optical performance of telescopes uncompromised by the turbulent atmosphere. This special section of Optical Engineering is devoted to space telescopes. It focuses on the design and implementation of major space observatories from the gamma-ray to far-infrared, and highlights the scientific and technical breakthroughs enabled by these telescopes. The papers accepted for publication include reviews of major space telescopes spanning the last two decades, in-depth discussions of the design considerations for visible and x-ray telescopes, and papers discussing concepts and technical challenges for future space telescopes.

  19. Data Management at the Southern African Large Telescope

    NASA Astrophysics Data System (ADS)

    Crawford, Steve

    2015-12-01

    PySALT is the python/PyRAF-based data reduction and analysis pipeline for the Southern African Large Telescope (SALT), a modern 10m class telescope with a large user community consisting of 13 partner institutions. The suite of tools developed as part of PySALT include: (1) science quality reductions for the major operational modes of SALT include high-time resolution and spectroscopic reductions, (2) quick-look capabilities for the observers and real-time data delivery for the investigators, and (3) management of the data archive and regularly processing of SALT observations. In addition to presenting the overall framework, we also highlight some of the lessons learned since the start of SALT scientific observations in 2011.

  20. The South Pole Telescope

    SciTech Connect

    Ruhl, J.E.; Ade, P.A.R.; Carlstrom, J.E.; Cho, H.M.; Crawford,T.; Dobbs, M.; Greer, C.H.; Halverson, N.W.; Holzapfel, W.L.; Lanting,T.M.; Lee, A.T.; Leitch, E.M.; Leong, J.; Lu, W.; Lueker, M.; Mehl, J.; Meyer, S.S.; Mohr, J.J.; Padin, S.; Plagge, T.; Pryke, C.; Runyan, M.C.; Schwan, D.; Sharp, M.K.; Spieler, H.; Staniszewski, Z.; Stark, A.A.

    2004-11-04

    A new 10 meter diameter telescope is being constructed for deployment at the NSF South Pole research station. The telescope is designed for conducting large-area millimeter and sub-millimeter wave surveys of faint, low contrast emission, as required to map primary and secondary anisotropies in the cosmic microwave background. To achieve the required sensitivity and resolution, the telescope design employs an off-axis primary with a 10 m diameter clear aperture. The full aperture and the associated optics will have a combined surface accuracy of better than 20 microns rms to allow precision operation in the submillimeter atmospheric windows. The telescope will be surrounded with a large reflecting ground screen to reduce sensitivity to thermal emission from the ground and local interference. The optics of the telescope will support a square degree field of view at 2mm wavelength and will feed a new 1000-element micro-lithographed planar bolometric array with superconducting transition-edge sensors and frequency-multiplexed readouts. The first key project will be to conduct a survey over 4000 degrees for galaxy clusters using the Sunyaev-Zeldovich Effect. This survey should find many thousands of clusters with a mass selection criteria that is remarkably uniform with redshift. Armed with redshifts obtained from optical and infrared follow-up observations, it is expected that the survey will enable significant constraints to be placed on the equation of state of the dark energy.

  1. Worth its SALT: four years of full science operations with the Southern African Large Telescope

    NASA Astrophysics Data System (ADS)

    Väisänen, Petri; Coetzee, Chris; Schroeder, Anja; Crawford, Steve M.; Buckley, David A. H.; Brink, Janus; Depagne, Éric; Kniazev, Alexei; Koen, Thea; Kotze, Paul; Marang, Fred; Miszalski, Brent; Romero Colmenero, Encarni; Strydom, Ockert; Van Wyk, Veronica; Williams, Theodore B.

    2016-07-01

    SALT is a 10-m class optical telescope located in Sutherland, South Africa. We present an update on all observatory performance metrics since the start of full science operations in late 2011, as well as key statistics describing the science efficiency and output of SALT, including the completion fractions of observations per priority class, and analysis of the more than 140 refereed papers to date. After addressing technical challenges and streamlining operations, these first years of full operations at SALT have seen good and consistently increasing rates of completion of high priority observations and, in particular, very cost-effective production of science publications.

  2. Networked Automatic Optical Telescopes

    NASA Astrophysics Data System (ADS)

    Mattox, J. R.

    2000-05-01

    Many groups around the world are developing automated or robotic optical observatories. The coordinated operation of automated optical telescopes at diverse sites could provide observing prospects which are not otherwise available, e.g., continuous optical photometry without diurnal interruption. Computer control and scheduling also offers the prospect of effective response to transient events such as γ -ray bursts. These telescopes could also serve science education by providing high-quality CCD data for educators and students. The Automatic Telescope Network (ATN) project has been undertaken to promote networking of automated telescopes. A web site is maintained at http://gamma.bu.edu/atn/. The development of such networks will be facilitated by the existence of standards. A set of standard commands for instrument and telescope control systems will allow for the creation of software for an ``observatory control system'' which can be used at any facility which complies with the TCS and ICS standards. Also, there is a strong need for standards for the specification of observations to be done, and reports on the results and status of observations. A proposed standard for this is the Remote Telescope Markup Language (RTML), which is expected to be described in another poster in this session. It may thus be feasible for amateur-astronomers to soon buy all necessary equipment and software to field an automatic telescope. The owner/operator could make otherwise unused telescope time available to the network in exchange for the utilization of other telescopes in the network --- including occasional utilization of meter-class telescopes with research-grade CCD detectors at good sites.

  3. Next Generation Space Telescope

    NASA Technical Reports Server (NTRS)

    Mather, John; Stockman, H. S.; Fisher, Richard R. (Technical Monitor)

    2000-01-01

    The Next Generation Space Telescope (NGST), planned for launch in 2009, will be an 8-m class radiatively cooled infrared telescope at the Lagrange point L2. It will cover the wavelength range from 0.6 to 28 microns with cameras and spectrometers, to observe the first luminous objects after the Big Bang, and the formation, growth, clustering, and evolution of galaxies, stars, and protoplanetary clouds, leading to better understanding of our own Origins. It will seek evidence of the cosmic dark matter through its gravitational effects. With an aperture three times greater than the Hubble Space Telescope, it will provide extraordinary advances in capabilities and enable the discovery of many new phenomena. It is a joint project of the NASA, ESA, and CSA, and scientific operations will be provided by the Space Telescope Science Institute.

  4. Reflections on the discovery space for a large ultraviolet-visible telescope: inputs from the European-led EUVO exercise

    NASA Astrophysics Data System (ADS)

    Gómez de Castro, Ana I.; Gaensicke, Boris; Neiner, Coralie; Barstow, Martin A.

    2016-10-01

    The solutions to a number of astrophysical problems require access to the ultraviolet, optical, and infrared from space-based facilities, with capabilities beyond those available with Hubble Space Telescope or James Webb Space Telescope. A large ultraviolet-optical-infrared telescope will need to have a large collecting area and milliarcsecond angular resolution capabilities plus highly efficient instruments, providing a revolutionary enhancement in capability. During 2013, the European astronomical community was involved in an exercise to outline the big science that could be achieved with such a facility; the proposal was called EUVO (as per European Ultraviolet-Visible Observatory). Inspired by that work, we describe a proposal on future science and instrumentation to be carried out with a 10-m class telescope.

  5. Telescope Equipment

    NASA Technical Reports Server (NTRS)

    1988-01-01

    Renaissance Telescope for high resolution and visual astronomy has five 82-degree Field Tele-Vue Nagler Eyepieces, some of the accessories that contribute to high image quality. Telescopes and eyepieces are representative of a family of optical equipment manufactured by Tele-Vue Optics, Inc.

  6. A high-precision angle encoder for a 10-m submillimeter antenna

    NASA Astrophysics Data System (ADS)

    Ukita, Nobuharu; Ezawa, Hajime; Mimura, Hisashi; Suganuma, Akira; Kitazawa, Kanji; Masuda, Tadashi; Kawaguchi, Noboru; Sugiyama, Ryuichi; Miyawaki, Keizou

    2001-03-01

    We report measurements of angle error characteristics of new high-precision multi-speed resolvers developed for a 10-m submillimeter telescope of Nobeyama Radio Observatory. We have found the resolvers have an accuracy of 0.03" rms and 0.26" peak-to-peak, which is well below the error budget assigned to the angle encoder in the LMSA/ALMA project (0.15 - 0.2"). The error pattern in the raw readout had simple characteristics and was only composed of a few Fourier components which are associated with the number of winding poles and core slot number of stator. The 4" peak-to-peak error in the raw readout is reduced to less than 1/15 by the PROM correction. We have also found that shaft misalignment causes only small changes of error pattern (0.08" error per 0.10 mm shaft misalignment), which enables us to install the resolver simply by the fitting. The temperature dependence of error pattern also seems to be small enough for the operation temperature range specified in the project.

  7. Teaching Telescopes

    ERIC Educational Resources Information Center

    Reid, John S.

    1974-01-01

    Discusses experience of teaching optical experiments with emphasis upon the student's design and construction of refracting and reflecting telescopes. Concludes that the student's interest and acquired knowledge are greatly enhanced through the use of realistic experiments. (CC)

  8. Space Telescopes

    DTIC Science & Technology

    2010-01-01

    the Kirkpatrick–Baez type systems and the focussing colli- mator or ‘ lobster -eye’ systems. 1http://henke.lbl.gov/optical constants/ 176 9. Space...mirror requires a longer telescope. Focussing collimator or ‘ lobster -eye’ telescopes The Wolter and the Kirkpatrick–Baez systems have in common a...9.13: Flat-mirror two-dimensional focussing collimator or detached lobster - eye configuration (Schmidt 1975). within one tube but from adjacent walls a

  9. MEGARA optical design: the new integral field unit and multi-object spectrograph for the GTC 10m telescope

    NASA Astrophysics Data System (ADS)

    García-Vargas, María. Luisa; Sánchez-Blanco, Ernesto; Carrasco, Esperanza; Gil de Paz, Armando; Páez, Gonzalo; Pérez, Ana; Gallego, Jesús; Sánchez, Francisco; Vílchez, José M.

    2012-12-01

    We describe the optical design of MEGARA, the future optical Integral Field Unit (IFU) and Multi-Object Spectrograph (MOS) for the 10.4-m Gran Telescopio CANARIAS (GTC). MEGARA is being built by a Consortium of public research institutions led by the Universidad Complutense de Madrid (UCM, Spain) that also includes INAOE (Mexico), IAA-CSIC (Spain) and UPM (Spain).

  10. Status of the Whipple Observatory Cerenkov air shower imaging telescope array

    NASA Technical Reports Server (NTRS)

    Akerlof, C. W.; Cawley, M. F.; Fegan, D. J.; Fennell, S.; Freeman, S.; Frishman, D.; Harris, K.; Hillas, A. M.; Jennings, D.; Lamb, R. C.

    1992-01-01

    Recently the power of the Cerenkov imaging technique in Very High Energy gamma-ray astronomy was demonstrated by the detection of the Crab nebula at high statistical significance. In order to further develop this technique to allow the detection of weaker or more distant sources a second 10 m class reflector was constructed about 120 m from the original instrument. The addition of the second reflector will allow both a reduction in the energy threshold and an improvement in the rejection of the hadronic background. The design and construction of the second reflector, Gamma Ray Astrophysics New Imaging TElescope (GRANITE) is described.

  11. Telescopic hindsight

    NASA Astrophysics Data System (ADS)

    Cox, Laurence

    2014-08-01

    In reply to the physicsworld.com blog post "Cosmic blunders that have held back science" (2 June, http://ow.ly/xwC7C), about an essay by the astronomer Avi Loeb in which he criticized, among others, his Harvard University predecessor Edward Pickering, who claimed in 1909 that telescopes had reached their optimal size.

  12. Infrared telescope

    NASA Technical Reports Server (NTRS)

    Karr, G. R.; Hendricks, J. B.

    1985-01-01

    The development of the Infrared Telescope for Spacelab 2 is discussed. The design, development, and testing required to interface a stationary superfluid helium dewar with a scanning cryostate capable of operating in the zero-g environment in the space shuttle bay is described.

  13. Selecting Your First Telescope.

    ERIC Educational Resources Information Center

    Harrington, Sherwood

    1982-01-01

    Designed for first-time telescope purchasers, provides information on how a telescope works; major telescope types (refractors, reflectors, compound telescopes); tripod, pier, altazimuth, and equatorial mounts; selecting a telescope; visiting an astronomy club; applications/limitations of telescope use; and tips on buying a telescope. Includes a…

  14. The Liverpool Telescope

    NASA Astrophysics Data System (ADS)

    Smith, Robert J.; Bates, S. D.; Clay, Neil R.; Fraser, Stephen N.; Marchant, J. M.; Mottram, C. J.; Steele, I. A.; Tomlinson, M. D.

    2011-03-01

    The Liverpool Telescope (LT) is a fully robotic 2m optical telescope at a world-class observatory site. It runs autonomously without direct human control either on site or remotely. It is not operated primarily for a single science project, but rather is a common-user facility, time allocated by an open, peer-review process and conducting a variety of optical and IR imaging, spectroscopic and polarimetric programs. This paper describes some of aspects of the site infrastructure and instrument suite designed specifically to support robust and reliable unsupervised operations. Aside from the telescope hardware, the other aspect of robotic operations is the mechanisms whereby users interact with the telescope and its automated scheduler. We describe how these have been implemented for the LT. Observing routinely since 2004, the LT has demonstrated it is possible to operate a large, common-user robotic observatory. Making the most of the flexibility afforded by fully robotic operations, development continues in collaboration with both observers and other observatories to develop observing modes to enable new science across the broad discipline of time-domain astrophysics.

  15. Estimation of Density of Localized States in Amorphous Se80Te20 and Se80Te10M10 (M = Cd, In, Sb) Alloys Using AC Conductivity Measurements

    NASA Astrophysics Data System (ADS)

    Chandel, N.; Mehta, N.; Kumar, A.

    2015-08-01

    The ac conductivity of amorphous Se80Te20 (a-Se80Te20) and amorphous Se80Te10M10 (a-Se80Te10M10) alloys has been measured as a function of temperature and frequency in a low-temperature regime. An analysis of the experimental data confirms that ac conductivity is reasonably well interpreted by the Austin-Mott model. The density of localized states was determined in the low-temperature region from 201 K to 280 K. Possible explanations of "metal-induced effects" on the conduction mechanism of a-Se80Te20 alloy are discussed.

  16. University of California ten meter telescope project

    NASA Astrophysics Data System (ADS)

    Nelson, J. E.

    1982-10-01

    A discussion is presented of the prospective design features of the segmented, 10-m diameter optical-IR range telescope which the University of California is planning to build on Mauna Kea, Hawaii, with attention to the performance levels obtained from prototypes. The telescope primary mirror will be formed by 36 actively controlled mirror segments, which will be polished to their desired shape by stressed mirror polishing. The active control system employs displacement sensors at the edges of the mirror segments to determine their positions, which are then adjusted by three displacement actuators/segment. The telescope overall design is described as a Ritchley-Cretien f/1.75-f/15 system. The telescope's dome is highly compact, and rotates on a stationary building in the manner of conventional telescope domes.

  17. High-energy gamma-ray emission from solar flares: Summary of Fermi large area telescope detections and analysis of two M-class flares

    SciTech Connect

    Ackermann, M.; Ajello, M.; Albert, A.; Allafort, A.; Bechtol, K.; Bottacini, E.; Buehler, R.; Baldini, L.; Barbiellini, G.; Bastieri, D.; Buson, S.; Bellazzini, R.; Bregeon, J.; Bissaldi, E.; Bonamente, E.; Bouvier, A.; Brandt, T. J.; Brigida, M.; Bruel, P.; and others

    2014-05-20

    We present the detections of 18 solar flares detected in high-energy γ-rays (above 100 MeV) with the Fermi Large Area Telescope (LAT) during its first 4 yr of operation. This work suggests that particle acceleration up to very high energies in solar flares is more common than previously thought, occurring even in modest flares, and for longer durations. Interestingly, all these flares are associated with fairly fast coronal mass ejections (CMEs). We then describe the detailed temporal, spatial, and spectral characteristics of the first two long-lasting events: the 2011 March 7 flare, a moderate (M3.7) impulsive flare followed by slowly varying γ-ray emission over 13 hr, and the 2011 June 7 M2.5 flare, which was followed by γ-ray emission lasting for 2 hr. We compare the Fermi LAT data with X-ray and proton data measurements from GOES and RHESSI. We argue that the γ-rays are more likely produced through pion decay than electron bremsstrahlung, and we find that the energy spectrum of the proton distribution softens during the extended emission of the 2011 March 7 flare. This would disfavor a trapping scenario for particles accelerated during the impulsive phase of the flare and point to a continuous acceleration process at play for the duration of the flares. CME shocks are known for accelerating the solar energetic particles (SEPs) observed in situ on similar timescales, but it might be challenging to explain the production of γ-rays at the surface of the Sun while the CME is halfway to the Earth. A stochastic turbulence acceleration process occurring in the solar corona is another likely scenario. Detailed comparison of characteristics of SEPs and γ-ray-emitting particles for several flares will be helpful to distinguish between these two possibilities.

  18. Robotic Telescopes

    NASA Astrophysics Data System (ADS)

    Akerlof, C. W.

    2001-05-01

    Since the discovery of gamma-ray bursts, a number of groups have attempted to detect correlated optical transients from these elusive objects. Following the flight of the BATSE instrument on the Compton Gamma-Ray Observatory in 1991, a prompt burst coordinate alert service, BACODINE (now GCN) became available to ground-based telescopes. Several instruments were built to take advantage of this facility, culminating in the discovery of a bright optical flash associated with GRB990123. To date, that single observation remains unique - no other prompt flashes have been seen for a dozen or so other bursts observed with comparably short response times. Thus, GRB prompt optical luminosities may be considerably dimmer than observed for the GRB990123 event or even absent altogether. A new generation of instruments is prepared to explore these possibilties using burst coordinates provided by HETE-2, Swift, Ballerina, Agile and other satellite missions. These telescopes have response times as short as a few seconds and reach limiting magnitudes, m_v 20, guaranteeing a sensitivity sufficient to detect the afterglow many hours later. Results from these experiments should provide important new data about the dynamics and locale of GRBs.

  19. Holographic telescope

    NASA Astrophysics Data System (ADS)

    Odhner, Jefferson E.

    2016-07-01

    Holographic optical elements (HOEs) work on the principal of diffraction and can in some cases replace conventional optical elements that work on the principal of refraction. An HOE can be thinner, lighter, can have more functionality, and can be lower cost than conventional optics. An HOE can serve as a beam splitter, spectral filter, mirror, and lens all at the same time. For a single wavelength system, an HOE can be an ideal solution but they have not been widely accepted for multispectral systems because they suffer from severe chromatic aberration. A refractive optical system also suffers from chromatic aberration but it is generally not as severe. To color correct a conventional refractive optical system, a flint glass and a crown glass are placed together such that the color dispersion of the flint and the crown cancel each other out making an achromatic lens (achromat) and the wavelengths all focus to the same point. The color dispersion of refractive lenses and holographic lenses are opposite from each other. In a diffractive optical system, long wavelengths focus closer (remember for HOEs: RBM "red bends more") than nominal focus while shorter wavelengths focus further out. In a refractive optical system, it is just the opposite. For this reason, diffractives can be incorporated into a refractive system to do the color correction and often cut down on the number of optical elements used [1.]. Color correction can also be achieved with an all-diffractive system by combining a holographic optical element with its conjugate. In this way the color dispersion of the first holographic optical element can be cancelled by the color dispersion of the second holographic optic. It is this technique that will be exploited in this paper to design a telescope made entirely of holographic optical elements. This telescope could be more portable (for field operations) the same technique could be used to make optics light enough for incorporation into a UAV.

  20. European Extremely Large Telescope: progress report

    NASA Astrophysics Data System (ADS)

    Tamai, R.; Spyromilio, J.

    2014-07-01

    The European Extremely Large Telescope is a project of the European Southern Observatory to build and operate a 40-m class optical near-infrared telescope. The telescope design effort is largely concluded and construction contracts are being placed with industry and academic/research institutes for the various components. The siting of the telescope in Northern Chile close to the Paranal site allows for an integrated operation of the facility providing significant economies. The progress of the project in various areas is presented in this paper and references to other papers at this SPIE meeting are made.

  1. Operational metrics for the ESO Very Large Telescope: lessons learned and future steps

    NASA Astrophysics Data System (ADS)

    Primas, F.; Marteau, S.; Tacconi-Garman, L. E.; Mainieri, V.; Mysore, S.; Rejkuba, M.; Hilker, M.; Patat, F.; Sterzik, M.; Kaufer, A.; Mieske, S.

    2016-07-01

    When ESO's Very Large Telescope opened its first dome in April 1999 it was the first ground-based facility to offer to the scientific community access to an 8-10m class telescope with both classical and queue observing. The latter was considered to be the most promising way to ensure the observing flexibility necessary to execute the most demanding scientific programmes under the required, usually very well defined, conditions. Since then new instruments have become operational and 1st generation ones replaced, filling the 12 VLT foci and feeding the VLT Interferometer and its four Auxiliary Telescopes. Operating efficiently such a broad range of instruments installed and available every night of the year on four 8-metre telescopes offers many challenges. Although it may appear that little has changed since 1999, the underlying VLT operational model has evolved in order to accommodate different requirements from the user community and features of new instruments. Did it fulfil its original goal and, if so, how well? How did it evolve? What are the lessons learned after more than 15 years of operations? A careful analysis and monitoring of statistics and trends in Phase 1 and Phase 2 has been deployed under the DOME (Dashboard for Operational Metrics at ESO) project. The main goal of DOME is to provide robust metrics that can be followed with time in a user-friendly manner. Here, we summarize the main findings on the handling of service mode observations and present the most recent developments.

  2. Concept Design for SOAR Telescope

    NASA Astrophysics Data System (ADS)

    Sebring, T.; Cecil, G.; Krabbendam, V.; Moretto, G.

    1998-12-01

    The Southern Astrophysical Research (SOAR) telescope is a \\$28M collaboration between Brazil, NOAO, Michigan State University, and the University of North Carolina at Chapel Hill. NOAO will operate the telescope for 20 years in exchange for 30 astronomers.) The project is now fully funded. This f/16 telescope is optimized for high-quality images across the isokinetic field (0."17 FWHM degradation from the telescope+facility over a field of 7.5' diameter.) It is being designed to take up to 2 Gemini-class (2100 kg) instruments, or a combination of lighter instruments at 7 Nasmyth and bent Cassegrain foci. The facility is now under construction atop Cerro Pachon, 400m from Gemini-S. First light is currently scheduled for early 2002. Corning Inc. is preparing to fabricate the 4.2m-diameter, 7.5-10 cm thick primary mirror from ULE glass. In early 1999 contacts will be awarded for 2 major subsystems: active optics (which includes optics polishing), and the alt.-az. telescope mount. We will outline the novel strategies that are being used to control project costs while optimizing telescope performance. Instrumentation plans will also be summarized.

  3. General surface equations for glancing incidence telescopes

    NASA Technical Reports Server (NTRS)

    Saha, Timo T.

    1987-01-01

    A generalized set of equations are derived for two mirror glancing incidence telescopes using Fermat's principle, a differential form of the law of reflection, the generalized sine condition, and a ray propagation equation described in vector form as a theoretical basis. The resulting formulation groups the possible telescope configurations into three distinct classes which are the Wolter, Wolter-Schwarzschild, and higher-order telescopes in which the Hettrick-Bowyer types are a subset. Eight configurations are possible within each class depending on the sign and magnitude of the parameters.

  4. Detectors for the South Pole Telescope

    NASA Astrophysics Data System (ADS)

    Chang, C. L.; Ade, P.; Aird, K.; Austermann, J.; Beall, J.; Becker, D.; Benson, B.; Bleem, L.; Britton, J.; Carlstrom, J.; Cho, H.; de Haan, T.; Crawford, T.; Crites, A.; Datesman, A.; Dobbs, M.; Everett, W.; Ewall-Wice, A.; George, E.; Halverson, N.; Harrington, N.; Henning, J.; Hilton, G.; Holzapfel, W.; Hoover, S.; Hubmayr, J.; Irwin, K.; Keisler, R.; Kennedy, J.; Lee, A.; Leitch, E.; Li, D.; Lueker, M.; Marrone, D. P.; Mcmahon, J.; Mehl, J.; Meyer, S.; Montgomery, J.; Montroy, T.; Natoli, T.; Nibarger, J.; Niemack, M.; Novosad, V.; Padin, S.; Plagge, T.; Pryke, C.; Reichardt, C.; Ruhl, J.; Saliwanchik, B.; Sayre, J.; Schafer, K.; Shirokoff, E.; Story, K.; Vanderlinde, K.; Vieira, J.; Wang, G.; Williamson, R.; Yefremenko, V.; Yoon, K. W.; Young, E.

    The South Pole Telescope (SPT) is a 10-m mm/sub-mm telescope at the Amundsen-Scott South Pole Station. It's primary science goals consist of a galaxy cluster survey for understanding Dark Energy and probing the physics of Inflation through the CMB polarization. Both science goals require exceptional sensitivity necessitating focal planes with many optical elements. The focal planes of the SPT utilize Transition Edge Sensor (TES) bolometers to build arrays of nearly 1000 detectors. In this talk, I will present the TES bolometer technology for both the first SPT focal plane and its upcoming upgrade to a polarization sensitive array.

  5. Astronomy with Small Telescopes

    NASA Astrophysics Data System (ADS)

    Paczyński, Bohdan

    2006-12-01

    The All Sky Automated Survey is monitoring the entire sky to about 14 mag with a cadence of about 1 day; it has discovered about 105 variable stars, most of them new. The instrument used for the survey had an aperture of 7 cm. A search for planetary transits has led to the discovery of about a dozen confirmed planets, so-called hot Jupiters, providing information on planetary masses and radii. Most discoveries were done with telescopes with apertures of 10 cm. We propose a search for optical transients covering the entire sky with a cadence of 10-30 minutes and a limit of 12-14 mag, with an instant verification of all candidate events. The search will be made with a large number of 10 cm instruments, and the verification will be done with 30 cm instruments. We also propose a system to be located at the L1 point of the Earth-Sun system to detect ``killer asteroids.'' With a limiting magnitude of about 18 mag, it could detect 10 m boulders several hours prior to their impact and provide warning against Tunguska-like events, as well as provide news about spectacular but more modest, harmless impacts.

  6. An optical technology study on large aperture telescopes

    NASA Technical Reports Server (NTRS)

    Korsch, D.

    1985-01-01

    The difficult and crucial problem of selecting a suitable telescope concept for an advanced space observatory was examined. To this end two and four mirror telescopes were analyzed and compared. Both configurations are very practical and structurally similar. Parabolic primary and spherical primary four mirror telescope were compared with respect to their performance and the alignment sensitivities of the three correction mirrors. A 1 meter class afocal telescope system with lag angle compensation, to be used in a LIDAR experiment, was examined.

  7. Satellite Attitude from a Raven Class Telescope

    DTIC Science & Technology

    2010-09-01

    Cache MATLAB was used as an interface to the jSim libraries, including orbit propagation, Earth Track determination, and satellite orientation methods...collection opportunities of the satellite. The combined software tool calculates the satellite orientation required to image the asset location... satellite orientation estimations, with only the photometric signatures with strong features being correctly estimated. The strong features that

  8. SNAP Telescope Latest Developments

    NASA Astrophysics Data System (ADS)

    Lampton, M.; SNAP Collaboration

    2004-12-01

    The coming era of precision cosmology imposes new demands on space telescopes with regard to spectrophotometric accuracy and image stability. To meet these requirements for SNAP we have developed an all reflecting two-meter-class space telescope of the three-mirror anastigmat type. Our design features a large flat annular field (1.5 degrees = 580mm diameter) and a telephoto advantage of 6, delivering a 22m focal length within an optical package length of only 3.5 meters. The use of highly stable materials (Corning ULE glass and carbon-fiber reinforced cyanate ester resin for the metering structure) combined with agressive distributed thermal control and an L2 orbit location will lead to unmatched figure stability. Owing to our choice of rigid structure with nondeployable solar panels, finite-element models show no structural resonances below 10Hz. An exhaustive stray light study has been completed. Beginning in 2005, two industry studies will develop plans for fabrication, integration and test, bringing SNAP to a highly realistic level of definition. SNAP is supported by the Office of Science, US DoE, under contract DE-AC03-76SF00098.

  9. Arrays vs. single telescopes

    NASA Astrophysics Data System (ADS)

    Johnson, H. L.

    The question of the relative efficiencies of telescope arrays versus an equivalent mirror-area very large telescope is re-examined and summarized. Four separate investigations by Bowen, Johnson and Richards, Code, and Disney all came to the same conclusion: that an array of telescopes is superior, both scientifically and economically, to a single very large telescope. The costs of recently completed telescopes are compared. The costs of arrays of telescopes are shown to be significantly lower than that of a single, very large telescope, with the further advantage that because existing, proven, designs can be used, no engineering 'break-throughs' are needed.

  10. Space hands-on universe telescope and orbiting wide-angle light-collector telescope to be built on the Japanese experiment module exposure facility of the international space station

    NASA Astrophysics Data System (ADS)

    Takahashi, Yoshiyuki; Ebisuzaki, Toshikazu; Pennypacker, Carlton

    1999-01-01

    A concept study to build great observatories on, and deploy from, the ISS is presented. Use of the ISS infra-structure including robotic arms and astronauts' EVA would permit a construction of very large optical telescopes. We envisage that the second phase of the ISS after its initial construction can landmark a new era for both ISS and Space Sciences. Ultimately, this study would plan a 10-or 20-meter class space telescope. For its first step, we envisioned an immediate extension of the Exposed Facility of ISS for building a ``Work-bench'' for this purpose. Initial activities can begin with two modest-sized telescopes soon after the ISS construction. These early missions being studied are space Hands-On Universe Telescope (SHOUT) and Orbiting Wide-angle Light-collector (OWL). SHOUT is a 1-m telescope for science education. It will be built and adjusted on the exposure module of the Japanese Experiment Module (JEM) of the International Space Station by using a robotic arm and the EVA of astronauts. We also seek the possibility to release it from ISS after its perfection on orbit, so that it is free from the vibrations and gas contaminations on and around the ISS. SHOUT is an engineering prototype of 10-m Space Telescope (Space SUBARU Telescope). It would be scaled from the Space-SUBARU telescope so that the testing with the SHOUT would warrant the required specifications for the 10-meter Space-SUBARU construction on the ISS. The goal of the test with the SHOUT is to warrant a spatial resolution of 0.01 arc-seconds using the active/adaptive optics. It will test the following three major engineering challenges: (1) active/adaptive optics in space; (2) building of large structures by astronauts; and (3) release of a spacecraft from ISS to a free-flying orbit. The present feasibility study for the next generation great observatories that are to be built on the JEM Exposure Facility (EF) has been already funded by the Japan Space Forum, under the auspices of the

  11. Space hands-on universe telescope and orbiting wide-angle light-collector telescope to be built on the Japanese experiment module exposure facility of the international space station

    SciTech Connect

    Takahashi, Y.; Ebisuzaki, T.; Pennypacker, C.

    1999-01-01

    A concept study to build great observatories on, and deploy from, the ISS is presented. Use of the ISS infra-structure including robotic arms and astronauts{close_quote} EVA would permit a construction of very large optical telescopes. We envisage that the second phase of the ISS after its initial construction can landmark a new era for both ISS and Space Sciences. Ultimately, this study would plan a 10-or 20-meter class space telescope. For its first step, we envisioned an immediate extension of the Exposed Facility of ISS for building a {open_quotes}Work-bench{close_quotes} for this purpose. Initial activities can begin with two modest-sized telescopes soon after the ISS construction. These early missions being studied are space Hands-On Universe Telescope (SHOUT) and Orbiting Wide-angle Light-collector (OWL). SHOUT is a 1-m telescope for science education. It will be built and adjusted on the exposure module of the Japanese Experiment Module (JEM) of the International Space Station by using a robotic arm and the EVA of astronauts. We also seek the possibility to release it from ISS after its perfection on orbit, so that it is free from the vibrations and gas contaminations on and around the ISS. SHOUT is an engineering prototype of 10-m Space Telescope (Space SUBARU Telescope). It would be scaled from the Space-SUBARU telescope so that the testing with the SHOUT would warrant the required specifications for the 10-meter Space-SUBARU construction on the ISS. The goal of the test with the SHOUT is to warrant a spatial resolution of 0.01 arc-seconds using the active/adaptive optics. It will test the following three major engineering challenges: (1) active/adaptive optics in space; (2) building of large structures by astronauts; and (3) release of a spacecraft from ISS to a free-flying orbit. The present feasibility study for the next generation great observatories that are to be built on the JEM Exposure Facility (EF) has been already funded by the Japan Space

  12. Crack growth of 10M Ni-Mn-Ga material in cyclic mechanical loading

    NASA Astrophysics Data System (ADS)

    Aaltio, I.; Ge, Y.; Pulkkinen, H.; Sjöberg, A.; Söderberg, O.; Liu, X. W.; Hannula, S.-P.

    The 10M martensitic Ni-Mn-Ga single crystal materials are usually applied in the magneto-mechanical actuators. Therefore, it is important to know the possible effect of the long-term cyclic shape changes on their structure and behavior. This can be evaluated with the mechanical fatigue testing. In the present study, the single crystal 10M Ni-Mn-Ga samples of different compositions were applied to strain-controlled uniaxial mechanical cycling in the multivariant state at ambient temperature. The experiments revealed distinctive changes of the twin variant structure, especially in the mobile twin area, density of twin boundaries, and in the tendency for fatigue crack growth. Characterization of the crack surface showed that the cracks in the microscale grow in a step-wise manner on specific crystallographic planes, i.e, twin boundary planes, but that the macroscopic crack does not occur only along crystallographic directions.

  13. EST: The European Solar Telescope

    NASA Astrophysics Data System (ADS)

    Collados, M.

    2008-09-01

    The European Solar Telescope (EST) is a project for a 4 meter-class ground-based telescope, to be located in the Canary Islands. The project is promoted by the European Association for Solar Telescopes (EAST), a consortium formed by research organizations from 15 European countries. EST will be optimized for studies of magnetic coupling between the deep photosphere and upper chromosphere. The project has been approved for funds by the European Union, within the FP-7 framework, to produce the design of all systems and subsystems of the telescope during the next three years. This includes the optical and optomechanical design of the telescope itself and of the instruments and their control. MCAO will be included in the optical path in a natural way to compensate for atmospheric disturbances in an optimum way. The design of EST will strongly emphasize the use of a large number of visible and near-infrared instruments simultaneously which will influence the telescope design from the very beginning. This communication will center mainly on the scientific objectives that EST will address. Generally speaking, they involve understanding how the magnetic field emerges through the solar surface, interacts with the plasma dynamics to transfer energy between different regions, and finally releases it in the form of heat or as violent events in the solar chromosphere and corona. Among the many topics of interest, one may cite, as described in the EST Science Requirements Document: small-scale flux emergence in quiet sun regions, large-scale magnetic structures, magnetic flux cancellation processes, polar magnetic fields, magnetic topology of the photosphere and chromosphere, conversion of mechanical to magnetic energy in the photosphere, wave propagation from photosphere to chromosphere, energy dissipation in the chromosphere at small and large scales, etc. The present status and future perspectives of the project will also be outlined.

  14. Identifying Meteor Streams Containing 10-m Bolides in Near-Earth Space and Determining their Temporal Evolution

    NASA Astrophysics Data System (ADS)

    Lai, H.; Russell, C. T.; Wei, H.; Delzanno, G.; Connors, M. G.

    2013-12-01

    The collision rate of small bodies orbiting the Sun increases with decreasing size. While small bodies in the 10-m class are difficult to detect from Earth, they are relatively easily detected by interplanetary spacecraft with magnetometers. A 10m body need be struck by a body only 20 cm across (traveling at 20 km/s) to be completely disrupted. The solar wind will sweep up the charged nano-scale dust as it flows through the debris forming a magnetic cloud. Because of the large size of the magnetic cloud only a small drop in the solar wind speed is needed to provide the momentum flux required to accelerate the cloud radially from the Sun. The cloud is carried outward and can be detected by any one of several interplanetary spacecraft. This procedure was first utilized on debris co-orbiting with the comet 2201 Oljato as monitored beginning in 1978 by the Pioneer Venus Orbiter and followed up by Venus Express that is still in operation. The meteoroid trail dissipated in just 30 years. We have used ACE, Wind and STEREO to identify a meteor stream co-orbiting with asteroid 138175 whose descending node is aligned with the Sun and the Earth on about April 17 each year. We have followed this trail from 1998 to the present and find that material extends to over 30° in front of the asteroid. It has been a steady producer of collisions over the last 15 years. The period of very close approach of this material to Earth may be over for a while but the material should be accessible by robotic or crewed missions as the orbit of 139175 has only a modest eccentricity and inclination to the ecliptic plane. Matching orbits with it should be similar in difficulty to a Venus flyby mission.

  15. Telescope performance at the Large Binocular Telescope

    NASA Astrophysics Data System (ADS)

    Hill, John M.; Rothberg, Barry; Christou, Julian C.; Summers, Kellee R.; Summers, Douglas M.

    2016-07-01

    The Large Binocular Telescope Observatory is a collaboration between institutions in Arizona, Germany, Italy, Indiana, Minnesota, Ohio and Virginia. The telescope uses two 8.4-m diameter primary mirrors mounted sideby- side on the same AZ-EL mount to produce a collecting area equivalent to an 11.8-meter aperture. Adaptive optics loops are routinely closed with natural stars on both sides for sided and combined beam observations. Rayleigh laser guide stars provide GLAO seeing improvement. With the telescope now in operation for 10 years, we report on various statistics of telescope performance and seeing-limited image quality. Statistics of telescope performance are reported in the areas of off-axis guiding, open-loop mount tracking, active optics and vibration. Delivered image quality is reported as measured by the DIMM and several guide cameras as a function of other parameters such as temperature and wind velocity. Projects to improve image quality and dome seeing are underway.

  16. 8-Meter UV/Optical Space Telescope

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2008-01-01

    This slide presentation proposes using the unprecedented capability of the planned Ares V launch vehicle, to place a 8 meter monolithic space telescope at the Earth-Sun L2 point. This new capability enables a new design pardigm -- simplicity. The six to eight meter class telescope with a massive high Technical Readiness Level ground observatory class monolithic primary mirror has been determined feasible. The proposed design, structural analysis, spacecraft design and shroud integration, thermal analysis, propulsion system, guidance navigation and pointing control assumptions about the avionics, and power systems, operational lifetime, and the idea of in-space servicing are reviewed.

  17. DISSOLUTION OF PLUTONIUM METAL IN 8-10 M NITRIC ACID

    SciTech Connect

    Rudisill, T.; Pierce, R.

    2012-02-21

    The H-Canyon facility will be used to dissolve Pu metal for subsequent purification and conversion to plutonium dioxide (PuO{sub 2}) using Phase II of HB-Line. To support the new mission, the development of a Pu metal dissolution flowsheet which utilizes concentrated (8-10 M) nitric acid (HNO{sub 3}) solutions containing potassium fluoride (KF) is required. Dissolution of Pu metal in concentrated HNO{sub 3} is desired to eliminate the need to adjust the solution acidity prior to purification by anion exchange. The preferred flowsheet would use 8-10 M HNO{sub 3}, 0.015-0.07 M KF, and 0.5-1.0 g/L Gd to dissolve the Pu up to 6.75 g/L. An alternate flowsheet would use 8-10 M HNO{sub 3}, 0.1-0.2 M KF, and 1-2 g/L B to dissolve the Pu. The targeted average Pu metal dissolution rate is 20 mg/min-cm{sup 2}, which is sufficient to dissolve a 'standard' 2250-g Pu metal button in 24 h. Plutonium metal dissolution rate measurements showed that if Gd is used as the nuclear poison, the optimum dissolution conditions occur in 10 M HNO{sub 3}, 0.04-0.05 M KF, and 0.5-1.0 g/L Gd at 112 to 116 C (boiling). These conditions will result in an estimated Pu metal dissolution rate of {approx}11-15 mg/min-cm{sup 2} and will result in dissolution times of 36-48 h for standard buttons. The recommended minimum and maximum KF concentrations are 0.03 M and 0.07 M, respectively. The maximum KF concentration is dictated by a potential room-temperature Pu-Gd-F precipitation issue at low Pu concentrations. The purpose of the experimental work described in this report was two-fold. Initially a series of screening experiments was performed to measure the dissolution rate of Pu metal as functions of the HNO{sub 3}, KF, and Gd or B concentrations. The objective of the screening tests was to propose optimized conditions for subsequent flowsheet demonstration tests. Based on the rate measurements, this study found that optimal dissolution conditions in solutions containing 0.5-1.0 g/L Gd occurred in 8-10

  18. The space telescope

    NASA Technical Reports Server (NTRS)

    1976-01-01

    Papers concerning the development of the Space Telescope which were presented at the Twenty-first Annual Meeting of the American Astronautical Society in August, 1975 are included. Mission planning, telescope performance, optical detectors, mirror construction, pointing and control systems, data management, and maintenance of the telescope are discussed.

  19. Telescopes and space exploration

    NASA Technical Reports Server (NTRS)

    Brandt, J. C.; Maran, S. P.

    1976-01-01

    The necessity for different types of telescopes for astronomical investigations is discussed. Major findings in modern astronomy by ground-based and spaceborne telescopes are presented. Observations of the Crab Nebula, solar flares, interstellar gas, and the Black Hole are described. The theory of the oscillating universe is explored. Operating and planned telescopes are described.

  20. LES Modeling of Lateral Dispersion in the Ocean on Scales of 10 m to 10 km

    DTIC Science & Technology

    2015-10-20

    Report 3. DATES COVERED (From - To) 01/07/2010 – 06/06/2015 4. TITLE AND SUBTITLE LES Modeling of Lateral Dispersion in the Ocean on Scales of 10...ocean on scales of 0.1-10 km that can be implemented in larger- scale ocean models. These parameterizations will incorporate the effects of local...Distribution approved for public release; distribution is unlimited. Final Report LES Modeling of Lateral Dispersion on Scales of 10 m to 10 km M.-Pascale

  1. Bioaerosol sampling by a personal rotating cup sampler CIP 10-M.

    PubMed

    Görner, Peter; Fabriès, Jean-François; Duquenne, Philippe; Witschger, Olivier; Wrobel, Richard

    2006-01-01

    High concentrations of bioaerosols containing bacterial, fungal and biotoxinic matter are encountered in many workplaces, e.g. solid waste treatment plants, waste water treatment plants and sewage networks. A personal bioaerosol sampler, the CIP 10-M (M-microbiologic), has been developed to measure worker exposure to airborne biological agents. This sampler is battery operated; it is light and easy to wear and offers full work shift autonomy. It can sample much higher concentrations than biological impactors and limits the mechanical stress on the microorganisms. Biological particles are collected in 2 ml of liquid medium inside a rotating cup fitted with radial vanes to maintain an air flow rate of 10 l min(-1) at a rotational speed of approximately 7,000 rpm. The rotating cup is made of sterilisable material. The sampled particles follow a helicoidal trajectory as they are pushed to the surface of the liquid by centrifugal force, which creates a thin vertical liquid layer. Sterile water or another collecting liquid can be used. Three particle size selectors allow health-related aerosol fractions to be sampled according to international conventions. The sampled microbiological particles can be easily recovered for counting, incubation or further biochemical analysis, e.g., for airborne endotoxins. Its physical sampling efficiency was laboratory tested and field trials were carried out in industrial waste management conditions. The results indicate satisfactory collection efficiency, whilst experimental application has demonstrated the usefulness of the CIP 10-M personal sampler for individual bioaerosol exposure monitoring.

  2. Solar Rejection Filter for Large Telescopes

    NASA Technical Reports Server (NTRS)

    Hemmati, Hamid; Lesh, James

    2009-01-01

    To reject solar radiation photons at the front aperture for large telescopes, a mosaic of large transmission mode filters is placed in front of the telescope or at the aperture of the dome. Filtering options for effective rejection of sunlight include a smaller filter down-path near the focus of the telescope, and a large-diameter filter located in the front of the main aperture. Two types of large filters are viable: reflectance mode and transmittance mode. In the case of reflectance mode, a dielectric coating on a suitable substrate (e.g. a low-thermal-expansion glass) is arranged to reflect only a single, narrow wavelength and to efficiently transmit all other wavelengths. These coatings are commonly referred to as notch filter. In this case, the large mirror located in front of the telescope aperture reflects the received (signal and background) light into the telescope. In the case of transmittance mode, a dielectric coating on a suitable substrate (glass, sapphire, clear plastic, membrane, and the like) is arranged to transmit only a single wavelength and to reject all other wavelengths (visible and near IR) of light. The substrate of the large filter will determine its mass. At first glance, a large optical filter with a diameter of up to 10 m, located in front of the main aperture, would require a significant thickness to avoid sagging. However, a segmented filter supported by a structurally rugged grid can support smaller filters. The obscuration introduced by the grid is minimal because the total area can be made insignificant. This configuration can be detrimental to a diffraction- limited telescope due to diffraction effects at the edges of each sub-panel. However, no discernable degradation would result for a 20 diffraction-limit telescope (a photon bucket). Even the small amount of sagging in each subpanel should have minimal effect in the performance of a non-diffraction limited telescope because the part has no appreciable optical power. If the

  3. Hubble Space Telescope Optical Telescope Assembly

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This image illustrates the Hubble Space Telescope's (HST's) Optical Telescope Assembly (OTA). One of the three major elements of the HST, the OTA consists of two mirrors (a primary mirror and a secondary mirror), support trusses, and the focal plane structure. The mirrors collect and focus light from selected celestial objects and are housed near the center of the telescope. The primary mirror captures light from objects in space and focuses it toward the secondary mirror. The secondary mirror redirects the light to a focal plane where the Scientific Instruments are located. The primary mirror is 94.5 inches (2.4 meters) in diameter and the secondary mirror is 12.2 inches (0.3 meters) in diameter. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth Orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from the Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The spacecraft is 42.5 feet (13 meters) long and weighs 25,000 pounds (11,600 kilograms). The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  4. Liverpool Telescope and Liverpool Telescope 2

    NASA Astrophysics Data System (ADS)

    Copperwheat, C. M.; Steele, I. A.; Barnsley, R. M.; Bates, S. D.; Clay, N. R.; Jermak, H.; Marchant, J. M.; Mottram, C. J.; Piascik, A.; Smith, R. J.

    2016-12-01

    The Liverpool Telescope is a fully robotic optical/near-infrared telescope with a 2-metre clear aperture, located at the Observatorio del Roque de los Muchachos on the Canary Island of La Palma. The telescope is owned and operated by Liverpool John Moores University, with financial support from the UK's Science and Technology Facilities Council. The telescope began routine science operations in 2004 and is a common-user facility with time available through a variety of committees via an open, peer reviewed process. Seven simultaneously mounted instruments support a broad science programme, with a focus on transient follow-up and other time domain topics well suited to the characteristics of robotic observing. Development has also begun on a successor facility, with the working title `Liverpool Telescope 2', to capitalise on the new era of time domain astronomy which will be brought about by the next generation of survey facilities such as LSST. The fully robotic Liverpool Telescope 2 will have a 4-metre aperture and an improved response time. In this paper we provide an overview of the current status of both facilities.

  5. Actuated Hybrid Mirror Telescope

    NASA Technical Reports Server (NTRS)

    Hickey, Gregory; Redding, David; Lowman, Andrew; Cohen, David; Ohara, Catherine

    2005-01-01

    The figure depicts the planned Actuated Hybrid Mirror Telescope (AHMT), which is intended to demonstrate a new approach to the design and construction of wide-aperture spaceborne telescopes for astronomy and Earth science. This technology is also appropriate for Earth-based telescopes. The new approach can be broadly summarized as using advanced lightweight mirrors that can be manufactured rapidly at relatively low cost. More specifically, it is planned to use precise replicated metallic nanolaminate mirrors to obtain the required high-quality optical finishes. Lightweight, dimensionally stable silicon carbide (SiC) structures will support the nanolaminate mirrors in the required surface figures. To enable diffraction- limited telescope performance, errors in surface figures will be corrected by use of mirror-shape-control actuators that will be energized, as needed, by a wave-front-sensing and control system. The concepts of nanolaminate materials and mirrors made from nanolaminate materials were discussed in several previous NASA Tech Briefs articles. Nanolaminates constitute a relatively new class of materials that can approach theoretical limits of stiffness and strength. Nanolaminate mirrors are synthesized by magnetron sputter deposition of metallic alloys and/or compounds on optically precise master surfaces to obtain optical-quality reflector surfaces backed by thin shell structures. As an integral part of the deposition process, a layer of gold that will constitute the reflective surface layer is deposited first, eliminating the need for a subsequent and separate reflective-coating process. The crystallographic textures of the nanolaminate will be controlled to optimize the performance of the mirror. The entire deposition process for making a nanolaminate mirror takes less than 100 hours, regardless of the mirror diameter. Each nanolaminate mirror will be bonded to its lightweight SiC supporting structure. The lightweight nanolaminate mirrors and Si

  6. DISSOLUTION OF PLUTONIUM METAL IN 8-10 M NITRIC ACID

    SciTech Connect

    Rudisill, T. S.; Pierce, R. A.

    2012-07-02

    The H-Canyon facility will be used to dissolve Pu metal for subsequent purification and conversion to plutonium dioxide (PuO{sub 2}) using Phase II of HB-Line. To support the new mission, the development of a Pu metal dissolution flowsheet which utilizes concentrated (8-10 M) nitric acid (HNO{sub 3}) solutions containing potassium fluoride (KF) is required. Dissolution of Pu metal in concentrated HNO{sub 3} is desired to eliminate the need to adjust the solution acidity prior to purification by anion exchange. The preferred flowsheet would use 8-10 M HNO{sub 3}, 0.015-0.07 M KF, and 0.5-1.0 g/L Gd to dissolve the Pu up to 6.75 g/L. An alternate flowsheet would use 8-10 M HNO{sub 3}, 0.05-0.2 M KF, and 1-2 g/L B to dissolve the Pu. The targeted average Pu metal dissolution rate is 20 mg/min-cm{sup 2}, which is sufficient to dissolve a “standard” 2250-g Pu metal button in 24 h. Plutonium metal dissolution rate measurements showed that if Gd is used as the nuclear poison, the optimum dissolution conditions occur in 10 M HNO{sub 3}, 0.04-0.05 M KF, and 0.5-1.0 g/L Gd at 112 to 116 °C (boiling). These conditions will result in an estimated Pu metal dissolution rate of ~11-15 mg/min-cm{sup 2} and will result in dissolution times of 36-48 h for standard buttons. The recommended minimum and maximum KF concentrations are 0.03 M and 0.07 M, respectively. The data also indicate that lower KF concentrations would yield dissolution rates for B comparable to those observed with Gd at the same HNO{sub 3} concentration and dissolution temperature. To confirm that the optimal conditions identified by the dissolution rate measurements can be used to dissolve Pu metal up to 6.75 g/L in the presence of representative concentrations of Fe and Gd or B, a series of experiments was performed to demonstrate the flowsheets. In three of the five experiments, the offgas generation rate during the dissolution was measured and samples were analyzed for hydrogen gas (H{sub 2}). The use of

  7. Deterministic separation of cancer cells from blood at 10 mL/min

    NASA Astrophysics Data System (ADS)

    Loutherback, Kevin; D'Silva, Joseph; Liu, Liyu; Wu, Amy; Austin, Robert H.; Sturm, James C.

    2012-12-01

    Circulating tumor cells (CTCs) and circulating clusters of cancer and stromal cells have been identified in the blood of patients with malignant cancer and can be used as a diagnostic for disease severity, assess the efficacy of different treatment strategies and possibly determine the eventual location of metastatic invasions for possible treatment. There is thus a critical need to isolate, propagate and characterize viable CTCs and clusters of cancer cells with their associated stroma cells. Here, we present a microfluidic device for mL/min flow rate, continuous-flow capture of viable CTCs from blood using deterministic lateral displacement (DLD) arrays. We show here that a DLD array device can isolate CTCs from blood with capture efficiency greater than 85% CTCs at volumetric flow rates of up to 10 mL/min with no effect on cell viability.

  8. Innovative Structural Design Features for a 10 m Solar Sail Demonstrator

    NASA Technical Reports Server (NTRS)

    Laue, G.; Moore, J.; Clayton, W.

    2004-01-01

    The successful development of sail architectures will require careful attention to a number of key issues including but not limited to material strength issues, stress conditions for the membrane, load interactions between membrane and structure, and membrane material planarity. Along with the inherent challenges of fabricating and handling very large membrane structures these issues will pose real challenges for the near-term development of practical sail technologies. SRS has developed innovative technologies that deal directly with the challenges of developing very large sail membranes. Some of these technologies include edge reinforcements and innovative reinforcement attachment techniques, production of flight durable sail materials of less than 2.5 micron thicknesses and large scale fabrication techniques. SRS has employed these technologies in several large 10 m demonstrators that have been delivered to LaRC for solar vacuum testing. Details of the design of this system will be discussed.

  9. Analysis of the Optical Design for the SAFIR Telescope

    NASA Technical Reports Server (NTRS)

    Goldsmith, Paul; Khayatian, Behrouz; Bradford, Matt; Dragovan, Mark; Hoppe, Daniel; Imbriale, William; Lee, Roger; Paine, Chris; Turner, Dick; Yorke, Harold; Zmuidzinas, Jonas

    2006-01-01

    SAFIR, the Single Aperture Far Infra Red Observatory, is a very powerful space mission that will achieve background-limited sensitivity in the far infrared-submillimeter spectral region. Many processes of enormous interest to astronomers can best be studied in this wavelength range, but require the demanding combination of high sensitivity, good angular resolution, and spectroscopic capability. SAFIR is a 10m class telescope to offering good angular resolution, cooled to below 5 K in order to achieve background-limited sensitivity, and equipped with a complement of large-format cameras and broadband spectrometers. Successful operation of such a facility is critically dependent on achieving the level of sensitivity expected, but this is rendered difficult by potential pickup from unwanted sources of radiation. This problem is exacerbated by the fact that the emission from the optical system itself is minimal due to its low temperature, thus emphasizing the importance of minimizing pickup from unwanted astronomical sources of radiation, including the emission from dust in our solar system (analogous to the zodiacal light, hence 'zodi'), and the emission from warm dust in the Milky Way (Galactic 'cirrus').

  10. 21 CFR 886.5870 - Low-vision telescope.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5870 Low-vision telescope. (a) Identification... use by a patient who has impaired vision to increase the apparent size of objects. This generic type of device includes handheld or spectacle telescopes. (b) Classification. Class I (general...

  11. 21 CFR 886.5870 - Low-vision telescope.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...) MEDICAL DEVICES OPHTHALMIC DEVICES Therapeutic Devices § 886.5870 Low-vision telescope. (a) Identification... use by a patient who has impaired vision to increase the apparent size of objects. This generic type of device includes handheld or spectacle telescopes. (b) Classification. Class I (general...

  12. JWST Pathfinder Telescope Integration

    NASA Technical Reports Server (NTRS)

    Matthews, Gary W.; Kennard, Scott H.; Broccolo, Ronald T.; Ellis, James M.; Daly, Elizabeth A.; Hahn, Walter G.; Amon, John N.; Mt. Pleasant, Stephen M.; Texter, Scott; Atkinson, Charles B.; McKay, Andrew; Levi, Joshua; Keski-Kuha, Ritva; Feinberg, Lee

    2015-01-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. In 2014, a major risk reduction effort related to the Alignment, Integration, and Test (AI&T) of the segmented telescope was completed. The Pathfinder telescope includes two Primary Mirror Segment Assemblies (PMSA's) and the Secondary Mirror Assembly (SMA) onto a flight-like composite telescope backplane. This pathfinder allowed the JWST team to assess the alignment process and to better understand the various error sources that need to be accommodated in the flight build. The successful completion of the Pathfinder Telescope provides a final integration roadmap for the flight operations that will start in August 2015.

  13. The Solar Telescope GREGOR

    NASA Astrophysics Data System (ADS)

    Volkmer, R.

    2008-09-01

    During the last years the new 1.5m solar telescope GREGOR was assembled at Izania on Tenerife, Spain. The telescope is designed for high-precision measurements of the magnetic field in the solar photosphere and chromosphere with a resolution of 70km on the Sun. The telescope concept offers also high resolution stellar spectroscopy. The telescope is build by a consortium of the Kiepenheuer-Institut für Sonnenphysik, the Astrophysikalische Institut Potsdam, the Institut für Astrophysik Göttingen, Max-Plank-Institut für Sonnensystemforschung and additional international Partners. The telescope is a complete open structure with active cooled main mirror. High performance post-focus instruments in the visible and near IR wavelength acquire high resolution spectra with 2 dimensional spatial resolution and polarimetric information. The commissioning of the telescope will start in 2008 to allow first science observations at the end of 2009.

  14. Automated telescope scheduling

    NASA Technical Reports Server (NTRS)

    Johnston, Mark D.

    1988-01-01

    With the ever increasing level of automation of astronomical telescopes the benefits and feasibility of automated planning and scheduling are becoming more apparent. Improved efficiency and increased overall telescope utilization are the most obvious goals. Automated scheduling at some level has been done for several satellite observatories, but the requirements on these systems were much less stringent than on modern ground or satellite observatories. The scheduling problem is particularly acute for Hubble Space Telescope: virtually all observations must be planned in excruciating detail weeks to months in advance. Space Telescope Science Institute has recently made significant progress on the scheduling problem by exploiting state-of-the-art artificial intelligence software technology. What is especially interesting is that this effort has already yielded software that is well suited to scheduling groundbased telescopes, including the problem of optimizing the coordinated scheduling of more than one telescope.

  15. Airborne Infrared Astronomical Telescopes

    NASA Astrophysics Data System (ADS)

    Erickson, Edwin F.

    2017-01-01

    A unique program of infrared astronomical observations from aircraft evolved at NASA’s Ames Research Center, beginning in the 1960s. Telescopes were flown on a Convair 990, a Lear Jet, and a Lockheed C-141 - the Kuiper Airborne Observatory (KAO) - leading to the planning and development of SOFIA: a 2.7 m telescope now flying on a Boeing 747SP. The poster describes these telescopes and highlights of some of the scientific results obtained from them.

  16. New telescope designs suitable for massively multiplexed spectroscopy

    NASA Astrophysics Data System (ADS)

    Pasquini, Luca; Delabre, B.; Ellis, R.; de Zeeuw, Tim

    2016-07-01

    We present two novel designs for a telescope suitable for massively-multiplexed spectroscopy. The first is a very wide field Cassegrain telescope optimised for fibre feeding. It provides a Field Of View (FOV) of 2.5 degrees diameter with a 10m primary mirror. It is telecentric and works at F/3, optimal for fibre injection. As an option, a gravity invariant focus for the central 10 arc-minutes can be added, to host, for instance, a giant integral field unit (IFU). It has acceptable performance in the 360-1300 nm wavelength range. The second concept is an innovative five mirror telescope design based on a Three Mirror Anastigmatic (TMA) concept. The design provides a large FOV in a convenient, gravityinvariant focal plane, and is scalable to a range of telescope diameters. As specific example, we present a 10m telescope with a 1.5 degree diameter FOV and a relay system that allows simultaneous spectroscopy with 10,000 mini-IFUs over a square degree, or, alternatively a 17.5 square arcminutes giant IFU, by using 240 MUSE-type spectrographs. We stress the importance of developing the telescope and instrument designs for both cases.

  17. The 10 Meter South Pole Telescope

    NASA Astrophysics Data System (ADS)

    Carlstrom, J. E.; Ade, P. A. R.; Aird, K. A.; Benson, B. A.; Bleem, L. E.; Busetti, S.; Chang, C. L.; Chauvin, E.; Cho, H.-M.; Crawford, T. M.; Crites, A. T.; Dobbs, M. A.; Halverson, N. W.; Heimsath, S.; Holzapfel, W. L.; Hrubes, J. D.; Joy, M.; Keisler, R.; Lanting, T. M.; Lee, A. T.; Leitch, E. M.; Leong, J.; Lu, W.; Lueker, M.; Luong-Van, D.; McMahon, J. J.; Mehl, J.; Meyer, S. S.; Mohr, J. J.; Montroy, T. E.; Padin, S.; Plagge, T.; Pryke, C.; Ruhl, J. E.; Schaffer, K. K.; Schwan, D.; Shirokoff, E.; Spieler, H. G.; Staniszewski, Z.; Stark, A. A.; Tucker, C.; Vanderlinde, K.; Vieira, J. D.; Williamson, R.

    2011-05-01

    The South Pole Telescope (SPT) is a 10 m diameter, wide-field, offset Gregorian telescope with a 966 pixel, multicolor, millimeter-wave, bolometer camera. It is located at the Amundsen-Scott South Pole station in Antarctica. The design of the SPT emphasizes careful control of spillover and scattering, to minimize noise and false signals due to ground pickup. The key initial project is a large-area survey at wavelengths of 3, 2, and 1.3 mm, to detect clusters of galaxies via the Sunyaev-Zel’dovich effect and to measure the small-scale angular power spectrum of the cosmic microwave background (CMB). The data will be used to characterize the primordial matter power spectrum and to place constraints on the equation of state of dark energy. A second-generation camera will measure the polarization of the CMB, potentially leading to constraints on the neutrino mass and the energy scale of inflation.

  18. An Examination of Residual Wind Fluctuations Observed at 10 m over Flat Terrain.

    NASA Astrophysics Data System (ADS)

    Leahey, D. M.; Hansen, M. C.; Schroeder, M. B.

    1996-01-01

    This study investigates the behavior of wind fluctuations observed at the 10-m level over a flat terrain site located some 100 km east of the Rocky Mountains. The purposes were to assess residual fluctuations in order to ascertain effects attributable to the nonhomogenous, nonstationary character of turbulence and to evaluate influences of gravity waves. Residual wind fluctuations were defined for purposes of this study as the differences between observed half-hourly average standard deviations of wind fluctuations (v, u, w) and those that are expected to occur in association with simultaneous wind speeds and static stabilities. These latter fluctuations were estimated from equations developed by Leahey, Hansen, and Schroeder (LHS).Results of the analyses showed, as expected, that residual distributions for nonwesterly wind conditions were nearly Gaussian. Standard deviations for residuals of horizontal fluctuations, attributable to the nonhomogenous, nonstationary nature of turbulence, were 0.165 and 0.210 m s1 for stable and unstable situations, respectively. For residuals associated with vertical fluctuations they were, respectively, 0.065 and 0.075 m s1.Residuals for horizontal and vertical wind fluctuations observed when winds were from the mountains showed a greater tendency for the positive bias associated with gravity waves. This tendency was most evident under unstable conditions when gravity wave influences on horizontal fluctuations were apparent about 25% of the time. These influences are explained as being associated with mountain lee waves occurring at the planetary boundary layer's capping inversion. They are evidenced at the 10-m level because atmospheric mixing processes occurring in thermally unstable atmospheric situations bring momentum generated from these waves downward to the ground.Nonstationary and nonhomogenous atmospheric turbulence effects result in wind fluctuations whose half-hourly average standard deviations differ from those

  19. Size-Frequency Distribution of Boulders ≥ 10 m on Comet 103P/Hartley 2

    NASA Astrophysics Data System (ADS)

    Pajola, M.; Lucchetti, A.; A'Hearn, M. F.; Bertini, I.; Marzari, F.; La Forgia, F.; Lazzarin, M.; Naletto, G.; Barbieri, C.

    2015-12-01

    We present the first size-frequency distribution of boulders ≥ 10 m identified on comet 103P/Hartley 2, computed from the images taken by the Deep Impact/High Resolution Imager - Visible CCD camera on 4 November 2010. We derived the size-frequency distribution of the illuminated side of the comet (˜ 50%), as well as identified the power-law indexes characterizing the two lobes of 103P. 332 boulders larger than 10 m were identified on the imaged surface of the comet, with a global number density of nearly 140/km2 and a cumulative size-frequency distribution represented by a power-law with index of -2.7 ± 0.2. The two lobes of 103P show close indexes, i.e. -2.7 ± 0.2 for the bigger lobe (L1) and -2.6 +0.2/-0.5 for the smaller one (L2). Both the similar power-law indexes and the similar maximum boulder sizes derived for the two lobes point towards a similar fracturing/disintegration phenomena of the boulders as well as similar lifting processes that may occur in L1 and L2. Nonetheless, the significative difference in the number of boulders per km2 between the two lobes suggests that the more diffuse H2O sublimation on the bigger lobe produce twice the boulders per km2 with respect to those produced on the small lobe (primary activity CO2 driven). If we compare the boulder distribution of the hyperactive 103P comet with similar studies performed on 67P (67P/Churyumov-Gerasimenko, i.e. the comet studied by Rosetta spacecraft), we derive that 103P shows a lower global power-law index (-2.7 vs -3.6). The size-frequency boulder trend of 103P is somehow closer to the -2.2 value measured on the neck region of 67P, i.e. the most active region of the northern hemisphere of 67P; nevertheless the hyperactivity of 103P works in a very different way than the normal activity of 67P in the neck/Hapi area. In addition to the global differences between the two comets' activities, the absence of cliffs and walls on 103P show a completely different surface geomorphology between

  20. Size-frequency distribution of boulders ≥10 m on comet 103P/Hartley 2

    NASA Astrophysics Data System (ADS)

    Pajola, Maurizio; Lucchetti, Alice; Bertini, Ivano; Marzari, Francesco; A'Hearn, Michael F.; La Forgia, Fiorangela; Lazzarin, Monica; Naletto, Giampiero; Barbieri, Cesare

    2016-01-01

    Aims: We derive the size-frequency distribution of boulders on comet 103P/Hartley 2, which are computed from the images taken by the Deep Impact/HRI-V imaging system. We indicate the possible physical processes that lead to these boulder size distributions. Methods: We used images acquired by the High Resolution Imager-Visible CCD camera on 4 November 2010. Boulders ≥10 m were identified and manually extracted from the datasets with the software ArcGIS. We derived the global size-frequency distribution of the illuminated side of the comet (~50%) and identified the power-law indexes characterizing the two lobes of 103P. The three-pixel sampling detection, together with the shadowing of the surface, enables unequivocally detection of boulders scattered all over the illuminated surface. Results: We identify 332 boulders ≥10 m on the imaged surface of the comet, with a global number density of nearly 140/km2 and a cumulative size-frequency distribution represented by a power law with index of -2.7 ± 0.2. The two lobes of 103P show similar indexes, i.e., -2.7 ± 0.2 for the bigger lobe (called L1) and -2.6+ 0.2/-0.5 for the smaller lobe (called L2). The similar power-law indexes and similar maximum boulder sizes derived for the two lobes both point toward a similar fracturing/disintegration phenomena of the boulders as well as similar lifting processes that may occur in L1 and L2. The difference in the number of boulders per km2 between L1 and L2 suggests that the more diffuse H2O sublimation on L1 produce twice the boulders per km2 with respect to those produced on L2 (primary activity CO2 driven). The 103P comet has a lower global power-law index (-2.7 vs. -3.6) with respect to 67P. The global differences between the two comets' activities, coupled with a completely different surface geomorphology, make 103P hardly comparable to 67P. A shape distribution analysis of boulders ≥30 m performed on 103P suggests that the cometary boulders show more elongated shapes

  1. The Next Generation Space Telescope

    NASA Technical Reports Server (NTRS)

    Bely, Pierre-Yves (Editor); Burrows,, Christopher J. (Editor); Illingworth,, Garth D.

    1989-01-01

    In Space Science in the Twenty-First Century, the Space Science Board of the National Research Council identified high-resolution-interferometry and high-throughput instruments as the imperative new initiatives for NASA in astronomy for the two decades spanning 1995 to 2015. In the optical range, the study recommended an 8 to 16-meter space telescope, destined to be the successor of the Hubble Space Telescope (HST), and to complement the ground-based 8 to 10-meter-class telescopes presently under construction. It might seem too early to start planning for a successor to HST. In fact, we are late. The lead time for such major missions is typically 25 years, and HST has been in the making even longer with its inception dating back to the early 1960s. The maturity of space technology and a more substantial technological base may lead to a shorter time scale for the development of the Next Generation Space Telescope (NGST). Optimistically, one could therefore anticipate that NGST be flown as early as 2010. On the other hand, the planned lifetime of HST is 15 years. So, even under the best circumstances, there will be a five year gap between the end of HST and the start of NGST. The purpose of this first workshop dedicated to NGST was to survey its scientific potential and technical challenges. The three-day meeting brought together 130 astronomers and engineers from government, industry and universities. Participants explored the technologies needed for building and operating the observatory, reviewed the current status and future prospects for astronomical instrumentation, and discussed the launch and space support capabilities likely to be available in the next decade. To focus discussion, the invited speakers were asked to base their presentations on two nominal concepts, a 10-meter telescope in space in high earth orbit, and a 16-meter telescope on the moon. The workshop closed with a panel discussion focused mainly on the scientific case, siting, and the

  2. Invited review article: A 10 mK scanning probe microscopy facility.

    PubMed

    Song, Young Jae; Otte, Alexander F; Shvarts, Vladimir; Zhao, Zuyu; Kuk, Young; Blankenship, Steven R; Band, Alan; Hess, Frank M; Stroscio, Joseph A

    2010-12-01

    We describe the design, development and performance of a scanning probe microscopy (SPM) facility operating at a base temperature of 10 mK in magnetic fields up to 15 T. The microscope is cooled by a custom designed, fully ultra-high vacuum (UHV) compatible dilution refrigerator (DR) and is capable of in situ tip and sample exchange. Subpicometer stability at the tip-sample junction is achieved through three independent vibration isolation stages and careful design of the dilution refrigerator. The system can be connected to, or disconnected from, a network of interconnected auxiliary UHV chambers, which include growth chambers for metal and semiconductor samples, a field-ion microscope for tip characterization, and a fully independent additional quick access low temperature scanning tunneling microscope (STM) and atomic force microscope (AFM) system. To characterize the system, we present the cooling performance of the DR, vibrational, tunneling current, and tip-sample displacement noise measurements. In addition, we show the spectral resolution capabilities with tunneling spectroscopy results obtained on an epitaxial graphene sample resolving the quantum Landau levels in a magnetic field, including the sublevels corresponding to the lifting of the electron spin and valley degeneracies.

  3. Deformation twinning in Ni–Mn–Ga micropillars with 10M martensite

    PubMed Central

    Reinhold, M.; Kiener, D.; Knowlton, W. B.; Dehm, G.; Müllner, P.

    2009-01-01

    The maximum actuation frequency of magnetic shape-memory alloys (MSMAs) significantly increases with decreasing size of the transducer making MSMAs interesting candidates for small scale actuator applications. To study the mechanical properties of Ni–Mn–Ga single crystals on small length scales, two single-domain micropillars with dimensions of 10×15×30 μm3 were fabricated from a Ni–Mn–Ga monocrystal using dual beam focused ion beam machining. The pillars were oriented such that the crystallographic c direction was perpendicular to the loading direction. The pillars were compressed to maximum stresses of 350 and 50 MPa, respectively. Atomic force microscopy and magnetic force microscopy were performed prior to fabrication of the pillars and following the deformation experiments. Both micropillars were deformed by twinning as evidenced by the stress-strain curve. For one pillar, a permanent deformation of 3.6% was observed and ac twins (10M martensite) were identified after unloading. For the other pillar, only 0.7% remained upon unloading. No twins were found in this pillar after unloading. The recovery of deformation is discussed in the light of pseudoelastic twinning and twin-substrate interaction. The twinning stress was higher than in similar macroscopic material. However, further studies are needed to substantiate a size effect. PMID:19859577

  4. SAAO small telescopes, capabilities and Challenges

    NASA Astrophysics Data System (ADS)

    Sefako, Ramotholo

    2015-03-01

    The SAAO is at a geographically crucial site in the southern hemisphere between South America and Australasia. SAAO has a long history of involvement in infrared and optical astronomy that dates back almost two hundred years. The observatory expects to continue contributing to astronomical research for many years to come, using its small (0.5m, 0.75m, 1.0m and 1.9m) telescopes and their various instruments (ranging from spectroscopy to polarimetry and high-speed photometry), together with the Southern African Large Telescope (SALT) and other hosted international telescopes. In this paper, I discuss the capabilities and uses of the SAAO small telescopes, and the challenges that threaten astronomical research at the observatory, including light pollution and other emerging threats to the usually dust-free and dark-night-sky site at Sutherland. This is mitigated by the legislation called the Astronomy Geographic Advantage (AGA) Act of 2007 that protects the observatory from these threats.

  5. High resolution telescope

    DOEpatents

    Massie, Norbert A.; Oster, Yale

    1992-01-01

    A large effective-aperture, low-cost optical telescope with diffraction-limited resolution enables ground-based observation of near-earth space objects. The telescope has a non-redundant, thinned-aperture array in a center-mount, single-structure space frame. It employs speckle interferometric imaging to achieve diffraction-limited resolution. The signal-to-noise ratio problem is mitigated by moving the wavelength of operation to the near-IR, and the image is sensed by a Silicon CCD. The steerable, single-structure array presents a constant pupil. The center-mount, radar-like mount enables low-earth orbit space objects to be tracked as well as increases stiffness of the space frame. In the preferred embodiment, the array has elemental telescopes with subaperture of 2.1 m in a circle-of-nine configuration. The telescope array has an effective aperture of 12 m which provides a diffraction-limited resolution of 0.02 arc seconds. Pathlength matching of the telescope array is maintained by an electro-optical system employing laser metrology. Speckle imaging relaxes pathlength matching tolerance by one order of magnitude as compared to phased arrays. Many features of the telescope contribute to substantial reduction in costs. These include eliminating the conventional protective dome and reducing on-site construction activites. The cost of the telescope scales with the first power of the aperture rather than its third power as in conventional telescopes.

  6. Video Telescope Operating Microscopy.

    PubMed

    Divers, Stephen J

    2015-09-01

    Exotic pet veterinarians frequently have to operate on small animals, and magnification is commonly used. Existing endoscopy equipment can be used with a mechanical arm and telescope to enable video telescope operating microscopy. The additional equipment items and their specifics are described, and several case examples are provided.

  7. Goddard Robotic Telescope

    SciTech Connect

    Sakamoto, Takanori; Donato, Davide; Gehrels, Neil; Okajima, Takashi; Ukwatta, Tilan N.

    2009-05-25

    We are constructing the 14'' fully automated optical robotic telescope, Goddard Robotic Telescope (GRT), at the Goddard Geophysical and Astronomical Observatory. The aims of our robotic telescope are 1) to follow-up the Swift/Fermi Gamma-Ray Bursts (GRBs) and 2) to perform the coordinated optical observations of the Fermi/Large Area Telescope (LAT) Active Galactic Nuclei (AGN). Our telescope system consists of the 14'' Celestron Optical Telescope Assembly (OTA), the Astro-Physics 1200GTO mount, the Apogee U47 CCD camera, the JMI's electronic focuser, and the Finger Lake Instrumentation's color filter wheel with U, B, V, R and I filters. With the focal reducer, 20'x20' field of view has been achieved. The observatory dome is the Astro Haven's 7 ft clam-shell dome. We started the scientific observations on mid-November 2008. While not observing our primary targets (GRBs and AGNs), we are planning to open our telescope time to the public for having a wider use of our telescope in both a different research field and an educational purpose.

  8. Lightweighted ZERODUR for telescopes

    NASA Astrophysics Data System (ADS)

    Westerhoff, T.; Davis, M.; Hartmann, P.; Hull, T.; Jedamzik, R.

    2014-07-01

    The glass ceramic ZERODUR® from SCHOTT has an excellent reputation as mirror blank material for earthbound and space telescope applications. It is known for its extremely low coefficient of thermal expansion (CTE) at room temperature and its excellent CTE homogeneity. Recent improvements in CNC machining at SCHOTT allow achieving extremely light weighted substrates up to 90% incorporating very thin ribs and face sheets. In 2012 new ZERODUR® grades EXPANSION CLASS 0 SPECIAL and EXTREME have been released that offer the tightest CTE grades ever. With ZERODUR® TAILORED it is even possible to offer ZERODUR® optimized for customer application temperature profiles. In 2013 SCHOTT started the development of a new dilatometer setup with the target to drive the industrial standard of high accuracy thermal expansion metrology to its limit. In recent years SCHOTT published several paper on improved bending strength of ZERODUR® and lifetime evaluation based on threshold values derived from 3 parameter Weibull distribution fitted to a multitude of stress data. ZERODUR® has been and is still being successfully used as mirror substrates for a large number of space missions. ZERODUR® was used for the secondary mirror in HST and for the Wolter mirrors in CHANDRA without any reported degradation of the optical image quality during the lifetime of the missions. Some years ago early studies on the compaction effects of electron radiation on ZERODUR® were re analyzed. Using a more relevant physical model based on a simplified bimetallic equation the expected deformation of samples exposed in laboratory and space could be predicted in a much more accurate way. The relevant ingredients for light weighted mirror substrates are discussed in this paper: substrate material with excellent homogeneity in its properties, sufficient bending strengths, space radiation hardness and CNC machining capabilities.

  9. Telescope Adaptive Optics Code

    SciTech Connect

    Phillion, D.

    2005-07-28

    The Telescope AO Code has general adaptive optics capabilities plus specialized models for three telescopes with either adaptive optics or active optics systems. It has the capability to generate either single-layer or distributed Kolmogorov turbulence phase screens using the FFT. Missing low order spatial frequencies are added using the Karhunen-Loeve expansion. The phase structure curve is extremely dose to the theoreUcal. Secondly, it has the capability to simulate an adaptive optics control systems. The default parameters are those of the Keck II adaptive optics system. Thirdly, it has a general wave optics capability to model the science camera halo due to scintillation from atmospheric turbulence and the telescope optics. Although this capability was implemented for the Gemini telescopes, the only default parameter specific to the Gemini telescopes is the primary mirror diameter. Finally, it has a model for the LSST active optics alignment strategy. This last model is highly specific to the LSST

  10. The solar optical telescope

    NASA Technical Reports Server (NTRS)

    1990-01-01

    Objectives of the Solar Optical Telescope are to study the physics of the Sun on the scale at which many of the important physical processes occur and to attain a resolution of 73km on the Sun or 0.1 arc seconds of angular resolution. Topics discussed in this overview of the Solar Optical Telescope include: why is the Solar Optical Telescope needed; current picture of the Sun's atmosphere and convection zone; scientific problems for the Solar Optical Telescope; a description of the telescope; the facility - science management, contamination control, and accessibility to the instruments; the scientific instruments - a coordinated instrument package for unlocking the Sun's secrets; parameters of the coordinated instrument package; science operations from the Space Shuttle; and the dynamic solar atmosphere.

  11. Thermal and Wind Effects on the Azimuth Axis Tilt of the ASTE 10-m Antenna

    NASA Astrophysics Data System (ADS)

    Ukita, Nobuharu; Ezawa, Hajime; Ikenoue, Bungo; Saito, Masao

    2007-10-01

    The azimuth axis tilt of the ASTE 10-m antenna induced by thermal and wind loadings was investigated with a dual-axis inclinometer on the azimuth axis, along with thermometers on the pedestal and yoke structures and an ultrasonic anemometer on a nearby weather station. The dependences of the inclinometer zero-point offsets against temperature of the device, temperature gradients in the pedestal and yoke structure were obtained for the measurements over 11 months during the antenna being parked at its home position (azimuth angles = ?180 degrees, an elevation angle = 60 degrees) under wind velocities < 8 m s-1. The temperature dependences of the zero-point offsets were found to be 1.24 and -0.46 arcseconds/degree, and were close to those obtained with an independent method. The azimuth axis tilts due to the temperature difference between the two opposite sides of pedestal walls were found to be about 1.1 and 1.7 arcseconds/degree, and consistent with 1.5 arcseconds/degree estimated with a simple model. The residual axis tilt of the whole samples after removal of the temperature dependences shows dependence against overturning moment estimated from the wind data. The stiffness of the antenna structures between the yoke base section and the ground was estimated to be 5.3 and 3.4 GNm/rad using the observed tilts in two directions; and were smaller than 6.0 GNm/rad from a mechanical model prediction. Based on these field experiments, we discuss the improvements and limitations of pointing performance with the inclinometer metrology system.

  12. Class Schedules Need Class.

    ERIC Educational Resources Information Center

    Monfette, Ronald J.

    1986-01-01

    Argues that college publications, including class schedules, must be accurate, timely, and easy to read and follow. Describes Schoolcraft College's unified format approach to publications marketing. Offers suggestions on the design, format, and distribution of class schedules. (DMM)

  13. Spherical Primary Optical Telescope (SPOT): An Architecture Demonstration for Cost-effective Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee D.; Hagopian, John; Budinoff, Jason; Dean, Bruce; Howard, Joe

    2004-01-01

    This paper summarizes efforts underway at the Goddard Space Flight Center to demonstrate a new type of space telescope architecture that builds on the rigid segmented telescope heritage of the James Webb Space Telescope but that solves several key challenges for future space telescopes. The architecture is based on a cost-effective segmented spherical primary mirror combined with a unique wavefront sensing and control system that allows for continuous phasing of the primary mirror. The segmented spherical primary allows for cost-effective 3-meter class (e.g., Midex and Discovery) missions as well as enables 30-meter telescope solutions that can be manufactured in a reasonable amount of time and for a reasonable amount of money. The continuous wavefront sensing and control architecture enables missions in low-earth-orbit and missions that do not require expensive stable structures and thermal control systems. For the 30-meter class applications, the paper discusses considerations for assembling and testing the telescopes in space. The paper also summarizes the scientific and technological roadmap for the architecture and also gives an overview of technology development, design studies, and testbed activities underway to demonstrate its feasibility.

  14. Spherical Primary Optical Telescope (SPOT): An Architecture Demonstration for Cost-effective Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee; Hagopian, John; Budinoff, Jason; Dean, Bruce; Howard, Joe

    2005-01-01

    This paper summarizes efforts underway at the Goddard Space Flight Center to demonstrate a new type of space telescope architecture that builds on the rigid, segmented telescope heritage of the James Webb Space Telescope but that solves several key challenges for future space telescopes. The architecture is based on a cost-effective segmented spherical primary mirror combined with a unique wavefront sensing and control system that allows for continuous phasing of the primary mirror. The segmented spherical primary allows for cost-effective 3-meter class (eg, Midex and Discovery) missions as well as enables 30-meter telescope solutions that can be manufactured in a reasonable amount of time and for a reasonable amount of money. The continuous wavefront sensing and control architecture enables missions in low-earth-orbit and missions that do not require expensive stable structures and thermal control systems. For the 30-meter class applications, the paper discusses considerations for assembling and testing the telescopes in space. The paper also summarizes the scientific and technological roadmap for the architecture and also gives an overview of technology development, design studies, and testbed activities underway to demonstrate it s feasibility.

  15. Two Easily Made Astronomical Telescopes.

    ERIC Educational Resources Information Center

    Hill, M.; Jacobs, D. J.

    1991-01-01

    The directions and diagrams for making a reflecting telescope and a refracting telescope are presented. These telescopes can be made by students out of plumbing parts and easily obtainable, inexpensive, optical components. (KR)

  16. The large binocular telescope.

    PubMed

    Hill, John M

    2010-06-01

    The Large Binocular Telescope (LBT) Observatory is a collaboration among institutions in Arizona, Germany, Italy, Indiana, Minnesota, Ohio, and Virginia. The telescope on Mount Graham in Southeastern Arizona uses two 8.4 m diameter primary mirrors mounted side by side. A unique feature of the LBT is that the light from the two Gregorian telescope sides can be combined to produce phased-array imaging of an extended field. This cophased imaging along with adaptive optics gives the telescope the diffraction-limited resolution of a 22.65 m aperture and a collecting area equivalent to an 11.8 m circular aperture. This paper describes the design, construction, and commissioning of this unique telescope. We report some sample astronomical results with the prime focus cameras. We comment on some of the technical challenges and solutions. The telescope uses two F/15 adaptive secondaries to correct atmospheric turbulence. The first of these adaptive mirrors has completed final system testing in Firenze, Italy, and is planned to be at the telescope by Spring 2010.

  17. The GREGOR Solar Telescope

    NASA Astrophysics Data System (ADS)

    Denker, C.; Lagg, A.; Puschmann, K. G.; Schmidt, D.; Schmidt, W.; Sobotka, M.; Soltau, D.; Strassmeier, K. G.; Volkmer, R.; von der Luehe, O.; Solanki, S. K.; Balthasar, H.; Bello Gonzalez, N.; Berkefeld, T.; Collados Vera, M.; Hofmann, A.; Kneer, F.

    2012-12-01

    The 1.5-meter GREGOR solar telescope is a new facility for high-resolution observations of the Sun. The telescope is located at the Spanish Observatorio del Teide on Tenerife. The telescope incorporates advanced designs for a foldable-tent dome, an open steel-truss telescope structure, and active and passive means to minimize telescope and mirror seeing. Solar fine structure can be observed with a dedicated suite of instruments: a broad-band imaging system, the "GREGOR Fabry-Perot Interferometer", and the "Grating Infrared Spectrograph". All post-focus instruments benefit from a high-order (multi-conjugate) adaptive optics system, which enables observations close to the diffraction limit of the telescope. The inclusion of a spectrograph for stellar activity studies and the search for solar twins expands the scientific usage of the GREGOR to the nighttime domain. We report on the successful commissioning of the telescope until the end of 2011 and the first steps towards science verification in 2012.

  18. Gemini telescope structure design

    NASA Astrophysics Data System (ADS)

    Raybould, Keith; Gillett, Paul E.; Hatton, Peter; Pentland, Gordon; Sheehan, Mike; Warner, Mark

    1994-06-01

    The Gemini project is an international collaboration to design, fabricate, and assemble two 8 M telescopes, one on Mauna Kea in Hawaii, the other on Cerro Pachon in Chile. The telescopes will be national facilities designed to meet the Gemini Science Requirements (GSR), a document developed by the Gemini Science Committee (GSC) and the national project scientists. The Gemini telescope group, based on Tucson, has developed a telescope structure to meet the GSR. This paper describes the science requirements that have technically driven the design, and the features that have been incorporated to meet these requirements. This is followed by a brief description of the telescope design. Finally, analyses that have been performed and development programs that have been undertaken are described briefly. Only the designs that have been performed by the Gemini Telescope Structure, Building and Enclosure Group are presented here; control, optical systems, acquisition and guiding, active and adaptive optics, Cassegrain rotator and instrumentation issues are designed and managed by others and will not be discussed here, except for a brief description of the telescope configurations to aid subsequent discussions.

  19. Restoration of an old telescope: a pedagogic opportunity

    NASA Astrophysics Data System (ADS)

    Gall Christophe, Le

    2016-04-01

    The "Lycée Jules Haag" High School is a former clockwork learning school. It has a telescope, built in the 1930's, which was used to calibrate time for watches. Nowadays, this telescope is no longer of any practical use, and has been classified for its historical interest. Thanks to the financial help of local companies, a new pedagogic project has started inside our school. This astronomical device is going to be repaired, and many teachers and classes will be involved. This will create opportunities during and after the restoration. Our High School will have practical classes that may work around the motorisation of the telescope and creating a new eyepiece. When the telescope is operational, we can use this device for physics and optics classes, and organise an astronomical club to do some day and night observations.

  20. Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    1990-01-01

    An overview of the mission of the Hubble Space Telescope, a joint project between NASA and the European Space Agency which will be used to study deep space, as well as our solar system is presented. The video contains animations depicting the Hubble Space Telescope in orbit, as well as footage of scientists at the Space Telescope Science Institute making real time observations. The images Hubble acquires will be downloaded into a database that contains images of over 19,000,000 celestial objects called the Star Catalog.

  1. Telescopic vision contact lens

    NASA Astrophysics Data System (ADS)

    Tremblay, Eric J.; Beer, R. Dirk; Arianpour, Ashkan; Ford, Joseph E.

    2011-03-01

    We present the concept, optical design, and first proof of principle experimental results for a telescopic contact lens intended to become a visual aid for age-related macular degeneration (AMD), providing magnification to the user without surgery or external head-mounted optics. Our contact lens optical system can provide a combination of telescopic and non-magnified vision through two independent optical paths through the contact lens. The magnified optical path incorporates a telescopic arrangement of positive and negative annular concentric reflectors to achieve 2.8x - 3x magnification on the eye, while light passing through a central clear aperture provides unmagnified vision.

  2. Multi-use lunar telescopes

    NASA Technical Reports Server (NTRS)

    Drummond, Mark; Hine, Butler; Genet, Russell; Genet, David; Talent, David; Boyd, Louis; Trueblood, Mark; Filippenko, Alexei V. (Editor)

    1991-01-01

    The objective of multi-use telescopes is to reduce the initial and operational costs of space telescopes to the point where a fair number of telescopes, a dozen or so, would be affordable. The basic approach is to develop a common telescope, control system, and power and communications subsystem that can be used with a wide variety of instrument payloads, i.e., imaging CCD cameras, photometers, spectrographs, etc. By having such a multi-use and multi-user telescope, a common practice for earth-based telescopes, development cost can be shared across many telescopes, and the telescopes can be produced in economical batches.

  3. Multi-use lunar telescopes

    NASA Technical Reports Server (NTRS)

    Genet, Russell M.; Genet, David R.; Talent, David L.; Drummond, Mark; Hine, Butler P.; Boyd, Louis J.; Trueblood, Mark

    1992-01-01

    The objective of multi-use telescopes is to reduce the initial and operational costs of space telescopes to the point where a fair number of telescopes, a dozen or so, would be affordable. The basic approach is to develop a common telescope, control system, and power and communications subsystem that can be used with a wide variety of instrument payloads, i.e., imaging CCD cameras, photometers, spectrographs, etc. By having such a multi-use and multi-user telescope, a common practice for earth-based telescopes, development cost can be shared across many telescopes, and the telescopes can be produced in economical batches.

  4. Mechanical design of SST-GATE, a dual-mirror telescope for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Dournaux, Jean-Laurent; Huet, Jean-Michel; Amans, Jean-Philippe; Dumas, Delphine; Laporte, Philippe; Sol, Hélène; Blake, Simon

    2014-07-01

    The Cherenkov Telescope Array (CTA) project aims to create the next generation Very High Energy (VHE) gamma-ray telescope array. It will be devoted to the observation of gamma rays over a wide band of energy, from a few tens of GeV to more than 100 TeV. Two sites are foreseen to view the whole sky where about 100 telescopes, composed of three different classes, related to the specific energy region to be investigated, will be installed. Among these, the Small Size class of Telescopes, SSTs, are devoted to the highest energy region, to beyond 100 TeV. Due to the large number of SSTs, their unit cost is an important parameter. At the Observatoire de Paris, we have designed a prototype of a Small Size Telescope named SST-GATE, based on the dual-mirror Schwarzschild-Couder optical formula, which has never before been implemented in the design of a telescope. Over the last two years, we developed a mechanical design for SST-GATE from the optical and preliminary mechanical designs made by the University of Durham. The integration of this telescope is currently in progress. Since the early stages of mechanical design of SST-GATE, finite element method has been used employing shape and topology optimization techniques to help design several elements of the telescope. This allowed optimization of the mechanical stiffness/mass ratio, leading to a lightweight and less expensive mechanical structure. These techniques and the resulting mechanical design are detailed in this paper. We will also describe the finite element analyses carried out to calculate the mechanical deformations and the stresses in the structure under observing and survival conditions.

  5. A Deployable Primary Mirror for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Phelps, James E.; Dyer, Jack E.; Caudle, David A.; Tam, Anthony; Escobedo, Javier; Kasl, Eldon P.

    1999-01-01

    NASA Langley Research Center, Composite Optics, Inc., and Nyma/ADF have developed jointly a deployable primary mirror for space telescopes that combines over five years of research on deployment of optical-precision structures and over ten years of development of fabrication techniques for optical-precision composite mirror panels and structures. The deployable mirror is directly applicable to a broad class of non-imaging "lidar" (light direction and ranging) telescopes whose figure-error requirements are in the range of one to ten microns RMS. Furthermore, the mirror design can be readily modified to accommodate imaging-quality reflector panels and active panel-alignment control mechanisms for application to imaging telescopes. The present paper: 1) describes the deployable mirror concept; 2) explains the status of the mirror development; and 3) provides some technical specifications for a 2.55-m-diameter, proof-of-concept mirror.

  6. Numerical simulation of ground-based telescope enclosures

    NASA Astrophysics Data System (ADS)

    Pan, Nian; Ma, Wenli; Huang, Jinlong

    2014-11-01

    In order to choose enclosure for the next generation telescopes, numerical simulation method was used. Firstly, the telescope, two general kinds of enclosures structure and the external flow field model were established, Then CFD(Computational Fluid Dynamics) technology was used to analyze the wind speed, static pressure, turbulence kinetic energy distribution and eddy around the telescope, when the telescope at two different pointing gestures and the external wind speed at 10m/s. The simulation results showed that when the telescope adapt the retractable enclosure, the wind speed of the main optical path between 6.1 m/s and 9.3 m/s, and the average static pressure (gauge pressure) on the primary mirror between 42.9268 Pa and 37.5579 Pa, however when telescope adapt the hemispherical enclosure, the wind speed of the main optical path between 3.4 m/s and 6.8 m/s, the average static pressure (gauge pressure) on the primary mirror between 12.1387 Pa and 11.105 Pa. Although the wind resistance of the retractable enclosure was lower than the hemispherical enclosure, no eddy generated near the main optical path, it provided the telescope a uniform flow field and ensured the quality of the image of a star. So the retractable enclosure would have better performance than the hemispherical enclosure.

  7. Webb Telescope: Planetary Evolution

    NASA Video Gallery

    Stars and planets form in the dark, inside vast, cold clouds of gas and dust. The James Webb Space Telescope's large mirror and infrared sensitivity will let astronomers peer inside dusty knots whe...

  8. Holographic telescope arrays.

    PubMed

    Lohmann, A W; Sauer, F

    1988-07-15

    A typical job in optical computing is to illuminate an array of small nonlinear optical components, separated by wide gaps to avoid crosstalk. We do this by letting a wide uniform beam fall onto a densely packed array of minifying telescopes. Each telescope produces a narrow bundle of parallel rays which illuminates one of the nonlinear optical components. The holographic telescopes can do more than change the width of the bundles of parallel rays. Their image forming capability allows the transmission of many pixels per channel in parallel. The pair of lenslets of a single holographic telescope (Kepler or Galilean) is produced in rigid coupling. The monolithic production avoids adjusting the two lenslets later on.

  9. Telescopes and space exploration

    NASA Technical Reports Server (NTRS)

    Brandt, J. C.; Maran, S. P.

    1982-01-01

    Progress in contemporary astronomy and astrophysics is shown to depend on complementary investigations with sensitive telescopes operating in several wavelength regions, some of which can be on the Earth's surface and others of which must be in space.

  10. Hubble Space Telescope Assembly

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This photograph shows the Hubble Space Telescope (HST) flight article assembly with multilayer insulation, high gain anterna, and solar arrays in a clean room of the Lockheed Missile and Space Company. The HST is the first of NASA's great observatories and the most complex and sensitive optical telescope ever made. The purpose of the HST is to study the cosmos from a low-Earth orbit by placing the telescope in space, enabling astronomers to collect data that is free of the Earth's atmosphere. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had overall responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company, Sunnyvale, California, produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  11. Composite Space Telescope Truss

    NASA Video Gallery

    NASA engineers are recycling an idea for a lightweight, compact space telescope structure from the early 1990s. The 315 struts and 84 nodes were originally designed to enable spacewalking astronaut...

  12. New catadioptric telescope

    NASA Astrophysics Data System (ADS)

    Richter, J. L.

    1981-01-01

    The Acme telescope is a compound telescope that resembles the familiar Cassegrain type except that the main mirror is spherical and the secondary is an achromatic doublet mangin mirror. Three 6-in. aperture f/15 telescope designs are described. With a cemented, all spherical surface achromangin mirror, there is a small amount of coma which can be eliminated by redesigning with an air space between the crown and flint elements of the achromangin mirror, or by cementing them with one of the concave external surfaces of achromangin figured to an hyperboloid. In the examples, the spherical aberration is nil and the chromatic residual is roughly half that of an achromatic objective of the same speed, aperture, and glass types. Readily available crown and flint glasses such as Schott BK-7 and F-2 are entirely satisfactory for the achromangin mirror. Also considered are two examples of Acme-like telescopes with paraboloidal instead of spherical main mirrors.

  13. Large Binocular Telescope Project

    NASA Astrophysics Data System (ADS)

    Hill, John M.

    1997-03-01

    The large binocular telescope (LBT) project have evolved from concepts first proposed in 1985. The present partners involved in the design and construction of this 2 by 8.4 meter binocular telescope are the University of Arizona, Italy represented by the Osservatorio Astrofisico di Arcetri and the Research Corporation based in Tucson, Arizona. These three partners have committed sufficient funds to build the enclosure and the telescope populated with a single 8.4 meter optical train -- approximately 40 million dollars (1989). Based on this commitment, design and construction activities are now moving forward. Additional partners are being sought. The next mirror to be cast at the Steward Observatory Mirror Lab in the fall of 1996 will be the first borosilicate honeycomb primary for LBT. The baseline optical configuration of LBT includes wide field Cassegrain secondaries with optical foci above the primaries to provide a corrected one degree field at F/4. The infrared F/15 secondaries are a Gregorian design to allow maximum flexibility for adaptive optics. The F/15 secondaries are undersized to provide a low thermal background focal plane which is unvignetted over a 4 arcminute diameter field-of-view. The interferometric focus combining the light from the two 8.4 meter primaries will reimage two folded Gregorian focal planes to a central location. The telescope elevation structure accommodates swing arms which allow rapid interchange of the various secondary and tertiary mirrors. Maximum stiffness and minimal thermal disturbance continue to be important drivers for the detailed design of the telescope. The telescope structure accommodates installation of a vacuum bell jar for aluminizing the primary mirrors in-situ on the telescope. The detailed design of the telescope structure will be completed in 1996 by ADS Italia (Lecco) and European Industrial Engineering (Mestre). The final enclosure design is now in progress at M3 Engineering (Tucson), EIE and ADS Italia

  14. Construction of the Advanced Technology Solar Telescope

    NASA Astrophysics Data System (ADS)

    Rimmele, T. R.; Keil, S.; McMullin, J.; Knölker, M.; Kuhn, J. R.; Goode, P. R.; Rosner, R.; Casini, R.; Lin, H.; Tritschler, A.; Wöger, F.; ATST Team

    2012-12-01

    The 4m Advance Technology Solar Telescope (ATST) will be the most powerful solar telescope and the world's leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun's output. The project has entered its construction phase. Major subsystems have been contracted. As its highest priority science driver ATST shall provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4m aperture, ATST will resolve features at 0.″03 at visible wavelengths and obtain 0.″1 resolution at the magnetically highly sensitive near infrared wavelengths. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the Coudé laboratory facility. The initial set of first generation instruments consists of five facility class instruments, including imagers and spectro-polarimeters. The high polarimetric sensitivity and accuracy required for measurements of the illusive solar magnetic fields place strong constraints on the polarization analysis and calibration. Development and construction of a four-meter solar telescope presents many technical challenges, including thermal control of the enclosure, telescope structure and optics and wavefront control. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the design status of the telescope and its instrumentation, including design status of major subsystems, such as the telescope mount assembly, enclosure, mirror assemblies, and wavefront correction

  15. Design of an afocal telescope for the ARIEL mission

    NASA Astrophysics Data System (ADS)

    Da Deppo, Vania; Middleton, Kevin; Focardi, Mauro; Morgante, Gianluca; Pace, Emanuele; Claudi, Riccardo; Micela, Giuseppina

    2016-07-01

    ARIEL (Atmospheric Remote-sensing Infrared Exoplanet Large-survey) is one of the three candidates for the next ESA medium-class science mission (M4) expected to be launched in 2026. This mission will be devoted to observe spectroscopically in the infrared (IR) a large population of known transiting planets in our Galaxy. ARIEL is based on a 1-m class telescope ahead of two spectrometer channels covering the band 1.95 to 7.8 microns. In addition there are four photometric channels: two wide band, also used as fine guidance sensors, and two narrow band. During its 3.5 years operations from L2 orbit, ARIEL will continuously observe exoplanets transiting their host star. The ARIEL design is conceived as a fore-module common afocal telescope that will feed the spectrometer and photometric channels. The telescope optical design is an off-axis portion of a two-mirror classic telescope coupled to a tertiary off-axis paraboloidal mirror providing a collimating output beam. The telescope and optical bench operating temperatures, as well as those of some subsystems, will be monitored and fine tuned/stabilised mainly by means of a thermal control subsystem (TCU - Telescope Control Unit) working in closed-loop feedback and hosted by the main Payload electronics unit, i.e. the Instrument Control Unit (ICU). In this paper the telescope requirements will be given together with the foreseen design. The technical solution chosen to passively cool the telescope unit will be detailed discussed.

  16. The Multiple-Mirror Telescope

    ERIC Educational Resources Information Center

    Carleton, Nathaniel P.; Hoffmann, William F.

    1978-01-01

    Describes the basic design and principle of operating an optical-infrared telescope, the MMT. This third largest telescope in the world represents a new stage in telescope design; it uses a cluster of six reflecting telescopes, and relies on an automatic sensing and control system. (GA)

  17. The Mercator telescope: relevance, status, and future

    NASA Astrophysics Data System (ADS)

    Raskin, Gert; Pessemier, Wim; Merges, Florian; Pérez Padilla, Jesus; Prins, Saskia; Van Winckel, Hans

    2014-07-01

    In todays era of ever growing telescope apertures, there remains a specific niche for meter-class telescopes, provided they are equipped with efficient and dedicated instruments. In case these telescopes have permanent and long-term availability, they turn out very useful for intensive monitoring campaigns over a large range of time-scales. Flexible scheduling and time allocation allow small telescopes to rapidly seize new opportunities or provide immediate follow-up observations to complement data from large ground-based or space-borne facilities. The Mercator telescope, a 1.2-m telescope, installed at the Roque de Los Muchachos Observatory on La Palma (Canary Islands, Spain), successfully targets this niche of intensive monitoring and flexible scheduling. Mercator is already in operation since 2001 and has seen several upgrades in the mean time. In this contribution we give an update about the actual telescope status and its performance. We also present the Mercator instrument suite that currently consists of two instruments. The workhorse instrument is HERMES, a very efficient and stable fibre-fed high-resolution spectrograph. Recently, the MAIA imager was commissioned. This is a three- channel photometric instrument that observes a large field simultaneously in the different color bands. The MAIA detectors are unique 6k x 2k frame transfer devices which also allow for fast and continuous monitoring of variable phenomena.We discuss two important upcoming upgrades: a long-awaited automatic mirror cover and, more importantly, an entirely new telescope control system (TCS). This TCS is based on modern PLC technology, and relies on OPC UA and EtherCAT communication. Only commercially off-the-shelve hardware will be used for controlling the telescope. As a test case and as a precursor of the full TCS, such PLC systems are already deployed at Mercator to steer the Nasmyth mirror mechanism and to control the MAIA instrument. Finally, we also give an overview of the

  18. Telescopes in education

    NASA Astrophysics Data System (ADS)

    Yessayian, Rick

    Imagine sitting in your classroom with your students and controlling a Research Grade 24 inch telescope. You control where it points, you control the duration of the exposure of a high grade CCD camera, and you control all of this within your school day, on a camera half way around the globe, in real time. You can hear the telescope moving, talk to the operator sitting atop historic Mt. Wilson Observatory in California. You might be looking at comets, asteroids, galaxies, nebulas or a host of other interesting celestial objects. Perhaps you have students that are up to a real challenge -- doing real science! Students in our program have contributed the discovery of a new variable star, to the Pluto Express project, to the search for supernovas, and the collection of images of intersecting galaxies. These are among the many possible projects you might choose from. The age and ability of your students are taken into account when you choose your project. Students from Kindergarten through Grade 12 have participated in this free program. A new robotic telescope was added at Mount Wilson in 1999. The telescope is a Celestron 14" SCT mounted on a Bisque Paramount GT-1100 with an Apogee AP-7 CCD camera (512X512 pixels). In the Spring of 2001, we duplicated the 14" robotic telescope configuration and placed it at the Las Campanas Observatory, Chile (operated by the Carnegie Observatories). I installed the system in late September, 2001, and we began testing. The system requires one more upgrade and some hardware adjustments, which I will complete in June, 2002. We duplicated another 14" robotic telescope, and sent it to Brisbane Australia in January, 2002. The grand opening of the telescope will be in August 2002.

  19. Paper Productivity of Ground-based Large Optical Telescopes from 2000 to 2009

    NASA Astrophysics Data System (ADS)

    Kim, Sang Chul

    2011-08-01

    We present an analysis of the scientific (refereed) paper productivity of the current largest (diameter>8m) ground-based optical (and infrared) telescopes during the ten-year period from 2000 to 2009. The telescopes for which we have gathered and analysed the scientific publication data are the two 10-m Keck telescopes, the four 8.2-m Very Large Telescopes (VLT), the two 8.1-m Gemini telescopes, the 8.2-m Subaru telescope, and the 9.2-m Hobby-Eberly Telescope (HET). We have analysed the numbers of papers published in various astronomical journals produced by using these telescopes. While the total numbers of papers from these observatories are largest for the VLT, followed by Keck, Gemini, Subaru, and HET, the number of papers produced by each component of the telescopes is largest for Keck, followed by VLT, Subaru, Gemini, and HET. In 2009, each telescope of the Keck, VLT, Gemini, Subaru, and HET observatories produced 135, 109, 93, 107, and 5 refereed papers, respectively. We have shown that each telescope of the Keck, VLT, Gemini, and Subaru observatories is producing 2.1+/-0.9 Nature and Science papers annually and these papers make up 1.7+/-0.8% of all refereed papers produced by using each of those telescopes. Extending this relation, we propose that this ratio of the number of Nature and Science papers to the total number of refereed papers that will be produced by future extremely large telescopes (ELTs) will remain similar. From a comparison of the publication trends of the above telescopes, we suggest that (i) having more than one telescope of the same kind at the same location and (ii) increasing the number of instruments available at the telescope are good ways to maximize the paper productivity.

  20. Monolithic afocal telescope

    NASA Technical Reports Server (NTRS)

    Roberts, William T. (Inventor)

    2010-01-01

    An afocal monolithic optical element formed of a shallow cylinder of optical material (glass, polymer, etc.) with fast aspheric surfaces, nominally confocal paraboloids, configured on the front and back surfaces. The front surface is substantially planar, and this lends itself to deposition of multi-layer stacks of thin dielectric and metal films to create a filter for rejecting out-of-band light. However, an aspheric section (for example, a paraboloid) can either be ground into a small area of this surface (for a Cassegrain-type telescope) or attached to the planar surface (for a Gregorian-type telescope). This aspheric section of the surface is then silvered to create the telescope's secondary mirror. The rear surface of the cylinder is figured into a steep, convex asphere (again, a paraboloid in the examples), and also made reflective to form the telescope's primary mirror. A small section of the rear surface (approximately the size of the secondary obscuration, depending on the required field of the telescope) is ground flat to provide an unpowered surface through which the collimated light beam can exit the optical element. This portion of the rear surface is made to transmit the light concentrated by the reflective surfaces, and can support the deposition of a spectral filter.

  1. Spectroradiometry with space telescopes

    NASA Astrophysics Data System (ADS)

    Pauluhn, Anuschka; Huber, Martin C. E.; Smith, Peter L.; Colina, Luis

    2015-12-01

    Radiometry, i.e. measuring the power of electromagnetic radiation—hitherto often referred to as "photometry"—is of fundamental importance in astronomy. We provide an overview of how to achieve a valid laboratory calibration of space telescopes and discuss ways to reliably extend this calibration to the spectroscopic telescope's performance in space. A lot of effort has been, and still is going into radiometric "calibration" of telescopes once they are in space; these methods use celestial primary and transfer standards and are based in part on stellar models. The history of the calibration of the Hubble Space Telescope serves as a platform to review these methods. However, we insist that a true calibration of spectroscopic space telescopes must directly be based on and traceable to laboratory standards, and thus be independent of the observations. This has recently become a well-supported aim, following the discovery of the acceleration of the cosmic expansion by use of type-Ia supernovae, and has led to plans for launching calibration rockets for the visible and infrared spectral range. This is timely, too, because an adequate exploitation of data from present space missions, such as Gaia, and from many current astronomical projects like Euclid and WFIRST demands higher radiometric accuracy than is generally available today. A survey of the calibration of instruments observing from the X-ray to the infrared spectral domains that include instrument- or mission-specific estimates of radiometric accuracies rounds off this review.

  2. Towers for Antarctic Telescopes

    NASA Astrophysics Data System (ADS)

    Hammerschlag, R. H.; Bettonvil, F. C. M.; Jägers, A. P. L.; Nielsen, G.

    To take advantage of the exceptional seeing above the boundary layer on Antarctic sites, a high-resolution telescope must be mounted on a support tower. An open transparent tower of framework minimizes the upward temperature-disturbed airflow. A typical minimum height is 30m. The tower platform has to be extremely stable against wind-induced rotational motions, which have to be less than fractions of an arc second, unusually small from a mechanical engineering viewpoint. In a traditional structure, structural deflections result in angular deflections of the telescope platform, which introduce tip and tilt motions in the telescope. However, a structure that is designed to deflect with parallel motion relative to the horizontal plane will undergo solely translation deflections in the telescope platform and thus will not degrade the image. The use of a parallel motion structure has been effectively demonstrated in the design of the 15-m tower for the Dutch Open Telescope (DOT) on La Palma. Special framework geometries are developed, which make it possible to construct high towers in stories having platforms with extreme stability against wind-induced tilt. These geometric solutions lead to constructions, being no more massive than a normal steel framework carrying the same load. Consequently, these lightweight towers are well suited to difficult sites as on Antarctica. A geometry with 4 stories has been worked out.

  3. The Travelling Telescope

    NASA Astrophysics Data System (ADS)

    Murabona Oduori, Susan

    2015-08-01

    The telescope has been around for more than 400 years, and through good use of it scientists have made many astonishing discoveries and begun to understand our place in the universe. Most people, however, have never looked through one. Yet it is a great tool for cool science and observation especially in a continent and country with beautifully dark skies. The Travelling Telescope project aims to invite people outside under the stars to learn about those curious lights in the sky.The Travelling Telescope aims to promote science learning to a wide range of Kenyan schools in various locations exchanging knowledge about the sky through direct observations of celestial bodies using state of the art telescopes. In addition to direct observing we also teach science using various hands-on activities and astronomy software, ideal for explaining concepts which are hard to understand, and for a better grasp of the sights visible through the telescope. We are dedicated to promoting science using astronomy especially in schools, targeting children from as young as 3 years to the youth, teachers, their parents and members of the public. Our presentation focuses on the OAD funded project in rural coastal Kenya.

  4. Robotic and Survey Telescopes

    NASA Astrophysics Data System (ADS)

    Woźniak, Przemysław

    Robotic telescopes are revolutionizing the way astronomers collect their dataand conduct sky surveys. This chapter begins with a discussion of principles thatguide the process of designing, constructing, and operating telescopes andobservatories that offer a varying degree of automation, from instruments remotelycontrolled by observers to fully autonomous systems requiring no humansupervision during their normal operations. Emphasis is placed on designtrade-offs involved in building end-to-end systems intended for a wide range ofscience applications. The second part of the chapter contains descriptions ofseveral projects and instruments, both existing and currently under development.It is an attempt to provide a representative selection of actual systems thatillustrates state of the art in technology, as well as important ideas and milestonesin the development of the field. The list of presented instruments spans the fullrange in size starting from small all-sky monitors, through midrange robotic andsurvey telescopes, and finishing with large robotic instruments and surveys.Explosive growth of telescope networking is enabling entirely new modesof interaction between the survey and follow-up observing. Increasingimportance of standardized communication protocols and software is stressed.These developments are driven by the fusion of robotic telescope hardware,massive storage and databases, real-time knowledge extraction, and datacross-correlation on a global scale. The chapter concludes with examplesof major science results enabled by these new technologies and futureprospects.

  5. The Discovery Channel Telescope: a wide-field telescope in Northern Arizona

    NASA Astrophysics Data System (ADS)

    Sebring, Thomas A.; Dunham, Edward W.; Millis, Robert L.

    2004-10-01

    Lowell Observatory has initiated the development of a four meter class optical telescope with significant capabilities for solar system and broad spectrum astronomical research. Key to the Discovery Channel Telescope (DCT) is the ability to rapidly switch between 2 degree FOV imaging via a prime focus camera to 30 arc min FOV instrumentation at Ritchey-Chrétien (RC) focus. The telescope is to be constructed at approximately 7700 feet altitude, Southeast of Flagstaff, Arizona at a site which has exhibited 0.6 arc sec best quartile seeing. The telescope will feature active optics and alignment capability and the Prime Focus Instrument will feature a Mosaic Focal Plane array of 40 2k x 4k CCDs. The RC instrument payload will be approximately 5000 lbs, allowing either large instruments or suites of co-mounted instruments. This telescope is being developed in partnership with Discovery Communications, Inc. (DCI), who will utilize the DCT and the association with Lowell Observatory to develop educational programming about astronomy and technology. The telescope will be a substantial enhancement to the current capabilities of Lowell Observatory.

  6. Conceptual design of a cryogenic system for the next-generation infrared space telescope SPICA

    NASA Astrophysics Data System (ADS)

    Sato, Y.; Sugita, H.; Shinozaki, K.; Okamoto, A.; Yamawaki, T.; Komatsu, K.; Nakagawa, T.; Murakami, H.; Matsuhara, H.; Murakami, M.; Takada, M.; Takai, S.; Okabayashi, A.; Kanao, K.; Tsunematsu, S.; Otsuka, K.; Narasaki, K.

    2010-07-01

    The conceptual design of the Space Infrared Telescope for Cosmology and Astrophysics (SPICA) has been studied as a pre-project of the Japan Aerospace Exploration Agency (JAXA) in collaboration with ESA to be launched in 2018. The SPICA is transferred into a halo orbit around the second Lagrangian point in the Sun-Earth system, where radiant cooling is available effectively. The SPICA has a large IR telescope 3 m in diameter, which is cooled without cryogen to below 6 K by the radiant and mechanical cooling system. Therefore, the SPICA mission will cover mid- and far-IR astronomy with high sensitivity and spatial resolution during a long period of over 5 years for goal. Most heat radiation from the sun and spacecraft is blocked by the Sun Shield and thermal radiation shields covered with Multi-Layer Insulator (MLI) to limit heat radiation to the Scientific Instrument Assembly (SIA). The SIA, which is composed of the primary mirrors and optical benches equipped with Focal Plane Instruments (FPIs), is refrigerated to below 6 K by two sets of 4K-class Joule-Thomson (JT) cooler with a cooling power of 40 mW at 4.5 K. The Far-IR detector is refrigerated to 1.7 K by two sets of 1K-class JT coolers with a cooling power of 10 mW at 1.7 K. Improvements for the higher reliability and sufficient cooling performance are required in the development of SPICA mechanical cryocoolers. Thermal analysis indicates that the SPICA cryogenic system works effectively to limit the total heat load on the SIA to 41.2 mW. This paper describes the conceptual design of the SPICA cryogenic system, which was established with thermal feasibility for nominal operation mode.

  7. Inexpensive Demonstration of Diffraction-Limited Telescope from NASA Stratospheric Balloons

    NASA Astrophysics Data System (ADS)

    Young, Elliot

    NASA s Balloon Program often flies payloads to altitudes of 120,000 ft or higher, above 99.5% of the atmosphere. At those altitudes, the imaging degradation due to atmospheric- induced wavefront errors is virtually zero. In 2009, the SUNRISE balloon mission quantified the wavefront errors with a Shack-Hartmann array and found no evidence of wavefront errors. This means that a large telescope on a balloon should be able to achieve diffraction-limited performance, provided it can be stabilized at a level that is finer than the diffraction limit. At visible wavelengths, the diffraction limit of a 1 or 2 m telescope is 0.1 arcsec or 0.05 arcsec, respectively. NASA recently demonstrated WASP (the Wallops Arc-Second Pointing system) on a balloon flight in October 2011, a coarse pointing system that kept a dummy telescope (24 ft long, 1500 lbs) stabilized at the 0.25 arcsec level. We propose to use an orthogonal transfer CCD (OTCCD) from MIT Lincoln Laboratory to improve the pointing to 0.05 arcsec, an order of magnitude better than the coarse pointing alone and sufficient to provide long integrations at the diffraction limit of a 2-m telescope. Imaging in visible wavelengths is an important new capability. Ground-based adaptive optics (AO) systems on 8-m and 10-m class telescope cannot effectively correct for atmospheric turbulence at wavelengths shorter than 1 μm; the atmospheric wavefront errors are larger at these wavelengths than in the infrared J-H-K bands. At present, only the Hubble Space Telescope can achieve 0.05 arcsec resolution images in visible wavelengths, a capability that is dramatically oversubscribed. With a camera based on an MIT/LL OTCCD, a 2-m balloon-borne telescope could match the spatial resolution of HST. Under this project (and in conjunction with a SWRI Internal Research proposal), we will perform ground tests of a motion-compensation camera based on an MIT/LL Orthogonal Transfer CCD (OTCCD). This device can shift charge in four directions

  8. The Nuclear Compton Telescope

    NASA Astrophysics Data System (ADS)

    Boggs, Steven E.; NCT Collaboration

    2011-09-01

    The Nuclear Compton Telescope (NCT) is a balloon-borne soft gamma-ray (0.2-10 MeV) telescope designed to perform wide-field imaging, high-resolution spectroscopy, and novel polarization analysis of astrophysical sources. NCT employs a novel Compton telescope design, utilizing 12 high spectral resolution germanium detectors, with the ability to localize photon interaction in three dimensions. NCT underwent its first science flight from Fort Sumner, NM in Spring 2009, and was partially destroyed during a second launch attempt from Alice Spring, Australia in Spring 2010. We will present an overview of the NCT program, including results from the Spring 2009 flight, as well as status and plans for the NCT program.

  9. Configurable Aperture Space Telescope

    NASA Technical Reports Server (NTRS)

    Ennico, Kimberly; Vassigh, Kenny; Bendek, Selman; Young, Zion W; Lynch, Dana H.

    2015-01-01

    In December 2014, we were awarded Center Innovation Fund to evaluate an optical and mechanical concept for a novel implementation of a segmented telescope based on modular, interconnected small sats (satlets). The concept is called CAST, a Configurable Aperture Space Telescope. With a current TRL is 2 we will aim to reach TLR 3 in Sept 2015 by demonstrating a 2x2 mirror system to validate our optical model and error budget, provide strawman mechanical architecture and structural damping analyses, and derive future satlet-based observatory performance requirements. CAST provides an alternative access to visible andor UV wavelength space telescope with 1-meter or larger aperture for NASA SMD Astrophysics and Planetary Science community after the retirement of HST.

  10. Configurable Aperture Space Telescope

    NASA Technical Reports Server (NTRS)

    Ennico, Kimberly; Bendek, Eduardo

    2015-01-01

    In December 2014, we were awarded Center Innovation Fund to evaluate an optical and mechanical concept for a novel implementation of a segmented telescope based on modular, interconnected small sats (satlets). The concept is called CAST, a Configurable Aperture Space Telescope. With a current TRL is 2 we will aim to reach TLR 3 in Sept 2015 by demonstrating a 2x2 mirror system to validate our optical model and error budget, provide straw man mechanical architecture and structural damping analyses, and derive future satlet-based observatory performance requirements. CAST provides an alternative access to visible and/or UV wavelength space telescope with 1-meter or larger aperture for NASA SMD Astrophysics and Planetary Science community after the retirement of HST

  11. LSST telescope modeling overview

    NASA Astrophysics Data System (ADS)

    Sebag, J.; Andrew, J.; Angeli, G.; Araujo, C.; Barr, J.; Callahan, S.; Cho, M.; Claver, C.; Daruich, F.; Gressler, W.; Hileman, E.; Liang, M.; Muller, G.; Neill, D.; Schoening, W.; Warner, M.; Wiecha, O.; Xin, B.; Orden Martinez, Alfredo; Perezagua Aguado, Manuel; García Marchena, Luis; Ruiz de Argandoña, Ismael

    2016-08-01

    During this early stage of construction of the Large Synoptic Survey Telescope (LSST), modeling has become a crucial system engineering process to ensure that the final detailed design of all the sub-systems that compose the telescope meet requirements and interfaces. Modeling includes multiple tools and types of analyses that are performed to address specific technical issues. Three-dimensional (3D) Computeraided Design (CAD) modeling has become central for controlling interfaces between subsystems and identifying potential interferences. The LSST Telescope dynamic requirements are challenging because of the nature of the LSST survey which requires a high cadence of rapid slews and short settling times. The combination of finite element methods (FEM), coupled with control system dynamic analysis, provides a method to validate these specifications. An overview of these modeling activities is reported in this paper including specific cases that illustrate its impact.

  12. Ultrathin zoom telescopic objective.

    PubMed

    Li, Lei; Wang, Di; Liu, Chao; Wang, Qiong-Hua

    2016-08-08

    We report an ultrathin zoom telescopic objective that can achieve continuous zoom change and has reduced compact volume. The objective consists of an annular folded lens and three electrowetting liquid lenses. The annular folded lens undertakes the main part of the focal power of the lens system. Due to a multiple-fold design, the optical path is folded in a lens with the thickness of ~1.98mm. The electrowetting liquid lenses constitute a zoom part. Based on the proposed objective, an ultrathin zoom telescopic camera is demonstrated. We analyze the properties of the proposed objective. The aperture of the proposed objective is ~15mm. The total length of the system is ~18mm with a tunable focal length ~48mm to ~65mm. Compared with the conventional zoom telescopic objective, the total length has been largely reduced.

  13. The Discovery Channel Telescope

    NASA Astrophysics Data System (ADS)

    Millis, R. L.; Dunham, E. W.; Sebring, T. A.; Smith, B. W.; de Kock, M.; Wiecha, O.

    2004-11-01

    The Discovery Channel Telescope (DCT) is a 4.2-m telescope to be built at a new site near Happy Jack, Arizona. The DCT features a large prime focus mosaic CCD camera with a 2-degree-diameter field of view especially designed for surveys of KBOs, Centaurs, NEAs and other moving or time-variable targets. The telescope can be switched quickly to a Ritchey-Chretien configuration for optical/IR spectroscopy or near-IR imaging. This flexibility allows timely follow-up physical studies of high priority objects discovered in survey mode. The ULE (ultra-low-expansion) meniscus primary and secondary mirror blanks for the telescope are currently in fabrication by Corning Glass. Goodrich Aerospace, Vertex RSI, M3 Engineering and Technology Corp., and e2v Technologies have recently completed in-depth conceptual design studies of the optics, mount, enclosure, and mosaic focal plane, respectively. The results of these studies were subjected to a formal design review in July, 2004. Site testing at the 7760-ft altitude Happy Jack site began in 2001. Differential image motion observations from 117 nights since January 1, 2003 gave median seeing of 0.84 arcsec FWHM, and the average of the first quartile was 0.62 arcsec. The National Environmental Policy Act (NEPA) process for securing long-term access to this site on the Coconino National Forest is nearing completion and ground breaking is expected in the spring of 2005. The Discovery Channel Telescope is a project of the Lowell Observatory with major financial support from Discovery Communications, Inc. (DCI). DCI plans ongoing television programming featuring the construction of the telescope and the research ultimately undertaken with the DCT. An additional partner can be accommodated in the project. Interested parties should contact the lead author.

  14. The ANTARES neutrino telescope

    NASA Astrophysics Data System (ADS)

    Distefano, Carla

    The ANTARES collaboration has completed in 2008 the construction of an underwater high-energy neutrino telescope in the Mediterranean Sea, located 40 km off the French coast at a depth of 2500 m. The detector consists of 885 optical modules, which are distributed in 12 detector lines, various calibration systems and devices for environmental measurements. With an instrumented volume of about 0.05 km3, ANTARES is the largest Cherenkov neutrino detector currently operating in the Northern hemisphere. A general overview on the ANTARES telescope is given. The preliminary results from the various physics analyses on the collected data will be presented.

  15. The Lunar Configurable Array Telescope (LCAT)

    NASA Astrophysics Data System (ADS)

    Meinel, Aden B.; Meinel, Marjorie P.

    1990-01-01

    The desire for a much larger space telescope than HST by astronomers is clearly demonstrated by the attendance at this Workshop. The reality is that a much larger space telescope than the HST collides with cost scaling reality. Coupled with this reality is the fact that any multi-billion dollar science project must have broad-based support from the science community and solid political support at both Presidential and Congressional levels. The HST successor is certainly in the same multi-billion dollar class as the Super Collider of the physics community, a project that has finally achieved the broad support base necessary for funding to follow. Advocacy of a bigger HST on the general grounds that 'bigger is better' will not be sufficient. A new concept needs to be developed that clearly diverges from scaling up of a traditional HST-type space telescope. With these realities in mind we have a few comments regarding the nature of a possible space telescope that may depart from what the organizers of this Workshop had in mind. The national goal declared by the President is Space Station, the Moon and Mars, in that order. Space Station is a potential location where a large system could be assembled prior to being sent into a high orbit. It is not a desirable environment for a large space telescope. Mars is not relevant as an observatory site. The Moon is very relevant for reasons we will address. Our comments are based on the premise of a permanent Lunar Outpost. One of the main arguments for a lunar telescope is a degree of permanency, that is, as long as a Lunar Outpost is maintained. In contrast, the relatively short lifetime of an orbiting telescope is a disadvantage, especially as a cost penalty. Access to a telescope in a 100,000 km orbit for refurbishment and resupply is a major problem with no solution in the present NASA planning. A telescope in conjunction with a Lunar Outpost means the possibility for continual upgrading or modifying the telescope to meet

  16. The Lunar Configurable Array Telescope (LCAT)

    NASA Technical Reports Server (NTRS)

    Meinel, Aden B.; Meinel, Marjorie P.

    1989-01-01

    The desire for a much larger space telescope than HST by astronomers is clearly demonstrated by the attendance at this Workshop. The reality is that a much larger space telescope than the HST collides with cost scaling reality. Coupled with this reality is the fact that any multi-billion dollar science project must have broad-based support from the science community and solid political support at both Presidential and Congressional levels. The HST successor is certainly in the same multi-billion dollar class as the Super Collider of the physics community, a project that has finally achieved the broad support base necessary for funding to follow. Advocacy of a bigger HST on the general grounds that 'bigger is better' will not be sufficient. A new concept needs to be developed that clearly diverges from scaling up of a traditional HST-type space telescope. With these realities in mind we have a few comments regarding the nature of a possible space telescope that may depart from what the organizers of this Workshop had in mind. The national goal declared by the President is Space Station, the Moon and Mars, in that order. Space Station is a potential location where a large system could be assembled prior to being sent into a high orbit. It is not a desirable environment for a large space telescope. Mars is not relevant as an observatory site. The Moon is very relevant for reasons we will address. Our comments are based on the premise of a permanent Lunar Outpost. One of the main arguments for a lunar telescope is a degree of permanency, that is, as long as a Lunar Outpost is maintained. In contrast, the relatively short lifetime of an orbiting telescope is a disadvantage, especially as a cost penalty. Access to a telescope in a 100,000 km orbit for refurbishment and resupply is a major problem with no solution in the present NASA planning. A telescope in conjunction with a Lunar Outpost means the possibility for continual upgrading or modifying the telescope to meet

  17. Space infrared telescope pointing control system. Automated star pattern recognition

    NASA Technical Reports Server (NTRS)

    Powell, J. D.; Vanbezooijen, R. W. H.

    1985-01-01

    The Space Infrared Telescope Facility (SIRTF) is a free flying spacecraft carrying a 1 meter class cryogenically cooled infrared telescope nearly three oders of magnitude most sensitive than the current generation of infrared telescopes. Three automatic target acquisition methods will be presented that are based on the use of an imaging star tracker. The methods are distinguished by the number of guidestars that are required per target, the amount of computational capability necessary, and the time required for the complete acquisition process. Each method is described in detail.

  18. Remote Observing with the Pomona College 1-meter telescope

    NASA Astrophysics Data System (ADS)

    Penprase, B.

    2005-12-01

    We summarize our operations during the past year with our 1-meter Pomona College telescope located in Wrightwood California at the Table Mountain site . New programs for observing GRB host galaxies, and monitoring open clusters for potential planetary transits are described. The remote observing makes use of the ACE control system, and we summarize the performance and operation of our telescope from its mountain site using campus internet links. During the year the telescope is used extensively in laboratory classes, and we describe some of the curricular impact the facility has had for our students.

  19. Cooling Technology for Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    DiPirro, Michael; Cleveland, Paul; Durand, Dale; Klavins, Andy; Muheim, Daniella; Paine, Christopher; Petach, Mike; Tenerelli, Domenick; Tolomeo, Jason; Walyus, Keith

    2007-01-01

    NASA's New Millennium Program funded an effort to develop a system cooling technology, which is applicable to all future infrared, sub-millimeter and millimeter cryogenic space telescopes. In particular, this technology is necessary for the proposed large space telescope Single Aperture Far-Infrared Telescope (SAFIR) mission. This technology will also enhance the performance and lower the risk and cost for other cryogenic missions. The new paradigm for cooling to low temperatures will involve passive cooling using lightweight deployable membranes that serve both as sunshields and V-groove radiators, in combination with active cooling using mechanical coolers operating down to 4 K. The Cooling Technology for Large Space Telescopes (LST) mission planned to develop and demonstrate a multi-layered sunshield, which is actively cooled by a multi-stage mechanical cryocooler, and further the models and analyses critical to scaling to future missions. The outer four layers of the sunshield cool passively by radiation, while the innermost layer is actively cooled to enable the sunshield to decrease the incident solar irradiance by a factor of more than one million. The cryocooler cools the inner layer of the sunshield to 20 K, and provides cooling to 6 K at a telescope mounting plate. The technology readiness level (TRL) of 7 will be achieved by the active cooling technology following the technology validation flight in Low Earth Orbit. In accordance with the New Millennium charter, tests and modeling are tightly integrated to advance the technology and the flight design for "ST-class" missions. Commercial off-the-shelf engineering analysis products are used to develop validated modeling capabilities to allow the techniques and results from LST to apply to a wide variety of future missions. The LST mission plans to "rewrite the book" on cryo-thermal testing and modeling techniques, and validate modeling techniques to scale to future space telescopes such as SAFIR.

  20. Hubble Space Telescope: The Telescope, the Observations & the Servicing Mission

    NASA Astrophysics Data System (ADS)

    1999-11-01

    Today the HST Archives contain more than 260 000 astronomical observations. More than 13 000 astronomical objects have been observed by hundreds of different groups of scientists. Direct proof of the scientific significance of this project is the record-breaking number of papers published : over 2400 to date. Some of HST's most memorable achievements are: * the discovery of myriads of very faint galaxies in the early Universe, * unprecedented, accurate measurements of distances to the farthest galaxies, * significant improvement in the determination of the Hubble constant and thus the age of the Universe, * confirmation of the existence of blacks holes, * a far better understanding of the birth, life and death of stars, * a very detailed look at the secrets of the process by which planets are created. Europe and HST ESA's contribution to HST represents a nominal investment of 15%. ESA provided one of the two imaging instruments - the Faint Object Camera (FOC) - and the solar panels. It also has 15 scientists and computer staff working at the Space Telescope Science Institute in Baltimore (Maryland). In Europe the astronomical community receives observational assistance from the Space Telescope European Coordinating Facility (ST-ECF) located in Garching, Munich. In return for ESA's investment, European astronomers have access to approximately 15% of the observing time. In reality the actual observing time competitively allocated to European astronomers is closer to 20%. Looking back at almost ten years of operation, the head of ST-ECF, European HST Project Scientist Piero Benvenuti states: "Hubble has been of paramount importance to European astronomy, much more than the mere 20% of observing time. It has given the opportunity for European scientists to use a top class instrument that Europe alone would not be able to build and operate. In specific areas of research they have now, mainly due to HST, achieved international leadership." One of the major reasons for

  1. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister with callouts and characteristics. The ATM was designed and developed by the Marshall Space Flight Center.

  2. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister. The ATM was designed and developed by the Marshall Space Flight Center.

  3. Apollo Telescope Mount Illustration

    NASA Technical Reports Server (NTRS)

    1971-01-01

    The Apollo Telescope Mount (ATM) served as the first marned astronomical observatory in space. It was designed for solar research from Earth orbit aboard the Skylab. This image is a cutaway illustration of the ATM canister with callouts. The ATM was designed and developed by the Marshall Space Flight Center.

  4. A Simple "Tubeless" Telescope

    ERIC Educational Resources Information Center

    Straulino, S.; Bonechi, L.

    2010-01-01

    Two lenses make it possible to create a simple telescope with quite large magnification. The set-up is very simple and can be reproduced in schools, provided the laboratory has a range of lenses with different focal lengths. In this article, the authors adopt the Keplerian configuration, which is composed of two converging lenses. This instrument,…

  5. The Falcon Telescope Network

    NASA Astrophysics Data System (ADS)

    Chun, F.; Tippets, R.; Dearborn, M.; Gresham, K.; Freckleton, R.; Douglas, M.

    2014-09-01

    The Falcon Telescope Network (FTN) is a global network of small aperture telescopes developed by the Center for Space Situational Awareness Research in the Department of Physics at the United States Air Force Academy (USAFA). Consisting of commercially available equipment, the FTN is a collaborative effort between USAFA and other educational institutions ranging from two- and four-year colleges to major research universities. USAFA provides the equipment (e.g. telescope, mount, camera, filter wheel, dome, weather station, computers and storage devices) while the educational partners provide the building and infrastructure to support an observatory. The user base includes USAFA along with K-12 and higher education faculty and students. Since the FTN has a general use purpose, objects of interest include satellites, astronomical research, and STEM support images. The raw imagery, all in the public domain, will be accessible to FTN partners and will be archived at USAFA in the Cadet Space Operations Center. FTN users will be able to submit observational requests via a web interface. The requests will then be prioritized based on the type of user, the object of interest, and a user-defined priority. A network wide schedule will be developed every 24 hours and each FTN site will autonomously execute its portion of the schedule. After an observational request is completed, the FTN user will receive notification of collection and a link to the data. The Falcon Telescope Network is an ambitious endeavor, but demonstrates the cooperation that can be achieved by multiple educational institutions.

  6. Exploring Galileo's Telescope

    ERIC Educational Resources Information Center

    Straulino, Samuele; Terzuoli, Alessandra

    2010-01-01

    In the first months of 2009, the International Year of Astronomy, the authors developed an educational project for middle-level students connected with the first astronomical discoveries that Galileo Galilei (1564-1642) made 400 years ago. The project included the construction of a basic telescope and the observation of the Moon. The project, if…

  7. Wearable telescopic contact lens.

    PubMed

    Arianpour, Ashkan; Schuster, Glenn M; Tremblay, Eric J; Stamenov, Igor; Groisman, Alex; Legerton, Jerry; Meyers, William; Amigo, Goretty Alonso; Ford, Joseph E

    2015-08-20

    We describe the design, fabrication, and testing of a 1.6 mm thick scleral contact lens providing both 1× and 2.8× magnified vision paths, intended for use as a switchable eye-borne telescopic low-vision aid. The F/9.7 telescopic vision path uses an 8.2 mm diameter annular entrance pupil and 4 internal reflections in a polymethyl methacrylate precision optic. This gas-impermeable insert is contained inside a smooth outer casing of rigid gas-permeable polymer, which also provides achromatic correction for refraction at the curved lens face. The unmagnified F/4.1 vision path is through the central aperture of the lens, with additional transmission between the annular telescope rings to enable peripheral vision. We discuss potential solutions for providing oxygenation for an extended wear version of the lens. The prototype lenses were characterized using a scale-model human eye, and telescope functionality was confirmed in a small-scale clinical (nondispensed) demonstration.

  8. Hubble Space Telescope Assembly

    NASA Technical Reports Server (NTRS)

    1986-01-01

    Engineers and technicians conduct a fit check of the Hubble Space Telescope (HST) Solar Array flight article in a clean room of the Lockheed Missile and Space Company. The Solar Array is 40- feet (12.1-meters) long and 8.2-feet (2.5-meters) wide, and provides power to the spacecraft. The HST is the first of NASA's great observatories and the most complex and sensitive optical telescope ever made. The purpose of the HST is to study the cosmos from a low-Earth orbit by placing the telescope in space, enabling astronomers to collect data that is free of the Earth's atmosphere. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had overall responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Cornecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company, Sunnyvale, California, produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  9. Membrane photon sieve telescopes.

    PubMed

    Andersen, Geoff

    2010-11-20

    We present results of research into the design and construction of membrane photon sieves as primaries for next-generation lightweight space telescopes. We have created prototypes in electroformed nickel as well as diazo and CP-1 polymer films. In two such cases, diffraction-limited imaging performance was demonstrated over a narrow bandwidth.

  10. A Novel Dust Telescope

    NASA Astrophysics Data System (ADS)

    Grün, E.; Srama, R.; Krüger, H.; Kempf, S.; Harris, D.; Conlon, T.; Auer, S.

    2001-11-01

    Dust particles in space, like photons, are born at remote sites in space and time. From knowledge of the dust particles' birthplace and the particles' bulk properties, we can learn about the remote environment out of which the particles were formed. This approach is carried out by means of a dust telescope on a dust observatory in space. A dust telescope is a combination of a dust trajectory sensor together with a chemical composition analyzer for dust particles. A novel dust telescope is described. It consists of a highly sensitive dust trajectory sensor, and a large area chemical dust analyzer. It can provide valuable information about the particles' birthplace which may not be accessible by other techniques. Dust particles' trajectories are determined by the measurement of the electric signals that are induced when a charged grain flies through an appropriately configured electrode systems. After the successful identification of a few charged micron-sized dust grains in space by the Cassini Cosmic Dust Analyzer, this dust telescope has a ten fold increased sensitivity of charge detection (10-16 Coulombs) and will be able to obtain trajectories for sub-micron sized dust grains. State-of-the art dust chemical analyzers have sufficient mass resolution to resolve ions with atomic mass numbers above 100. However, since their impact areas are small they can analyze statistically meaningful numbers of grains only in the dust-rich environments of comets or ringed planets. Therefore, this dust telescope includes a large area (0.1 m2) chemical dust analyzer of mass resolution > 100 that will allow us to obtain statistically significant measurements of interplanetary and interstellar dust grains in space.

  11. Giant Magellan Telescope: overview

    NASA Astrophysics Data System (ADS)

    Johns, Matt; McCarthy, Patrick; Raybould, Keith; Bouchez, Antonin; Farahani, Arash; Filgueira, Jose; Jacoby, George; Shectman, Steve; Sheehan, Michael

    2012-09-01

    The Giant Magellan Telescope (GMT) is a 25-meter optical/infrared extremely large telescope that is being built by an international consortium of universities and research institutions. It will be located at the Las Campanas Observatory, Chile. The GMT primary mirror consists of seven 8.4-m borosilicate honeycomb mirror segments made at the Steward Observatory Mirror Lab (SOML). Six identical off-axis segments and one on-axis segment are arranged on a single nearly-paraboloidal parent surface having an overall focal ratio of f/0.7. The fabrication, testing and verification procedures required to produce the closely-matched off-axis mirror segments were developed during the production of the first mirror. Production of the second and third off-axis segments is underway. GMT incorporates a seven-segment Gregorian adaptive secondary to implement three modes of adaptive-optics operation: natural-guide star AO, laser-tomography AO, and ground-layer AO. A wide-field corrector/ADC is available for use in seeing-limited mode over a 20-arcmin diameter field of view. Up to seven instruments can be mounted simultaneously on the telescope in a large Gregorian Instrument Rotator. Conceptual design studies were completed for six AO and seeing-limited instruments, plus a multi-object fiber feed, and a roadmap for phased deployment of the GMT instrument suite is being developed. The partner institutions have made firm commitments for approximately 45% of the funds required to build the telescope. Project Office efforts are currently focused on advancing the telescope and enclosure design in preparation for subsystem- and system-level preliminary design reviews which are scheduled to be completed in the first half of 2013.

  12. An early lunar-based telescope - The Lunar Transit Telescope (LTT)

    NASA Technical Reports Server (NTRS)

    Mcgraw, John T.

    1990-01-01

    The first telescope accompanying return to the moon, a simple but elegant two meter class instrument capable of producing an extraordinary survey of the universe is proposed. This telescope produces a deep image of the sky obtained simultaneously in several broad bandpasses in the wavelength range from about 0.1 to 2 microns, with diffraction limited imaging in the infrared and approximately 0.1 arcsec resolution at shorter wavelengths. In an 18.6 year mission, the survey would include approximately 2 percent of the sky with multiple observations of all the surveyed area. This survey is accomplished with a telescope which has no moving parts and requires no continuing support beyond initial deployment.

  13. The Advanced Technology Solar Telescope: beginning construction of the world's largest solar telescope

    NASA Astrophysics Data System (ADS)

    Rimmele, T. R.; Wagner, J.; Keil, S.; Elmore, D.; Hubbard, R.; Hansen, E.; Warner, M.; Jeffers, P.; Phelps, L.; Marshall, H.; Goodrich, B.; Richards, K.; Hegwer, S.; Kneale, R.; Ditsler, J.

    2010-07-01

    The 4m Advance Technology Solar Telescope (ATST) will be the most powerful solar telescope and the world's leading ground-based resource for studying solar magnetism that controls the solar wind, flares, coronal mass ejections and variability in the Sun's output. The project has successfully passed its final design review and the Environmental Impact Study for construction of ATST on Haleakala, Maui, HI has been concluded in December of 2009. The project is now entering its construction phase. As its highest priority science driver ATST shall provide high resolution and high sensitivity observations of the dynamic solar magnetic fields throughout the solar atmosphere, including the corona at infrared wavelengths. With its 4 m aperture, ATST will resolve features at 0."03 at visible wavelengths and obtain 0."1 resolution at the magnetically highly sensitive near infrared wavelengths. A high order adaptive optics system delivers a corrected beam to the initial set of state-of-the-art, facility class instrumentation located in the coudé laboratory facility. The initial set of first generation instruments consists of five facility class instruments, including imagers and spectropolarimeters. The high polarimetric sensitivity and accuracy required for measurements of the illusive solar magnetic fields place strong constraints on the polarization analysis and calibration. Development and construction of a fourmeter solar telescope presents many technical challenges, including thermal control of the enclosure, telescope structure and optics and wavefront control. A brief overview of the science goals and observational requirements of the ATST will be given, followed by a summary of the design status of the telescope and its instrumentation, including design status of major subsystems, such as the telescope mount assembly, enclosure, mirror assemblies, and wavefront correction

  14. A Deployable Primary Mirror for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Lake, Mark S.; Phelps, James E.; Dyer, Jack E.; Caudle, David A.; Tam, Anthony; Escobedo, Javier; Kasl, Eldon P.

    1999-01-01

    NASA Langley Research Center, Composite Optics, Inc., and Nyma/ADF have developed jointly a deployable primary mirror for space telescopes that combines over five years of research on deployment of optical-precision structures and over ten years of development of fabrication techniques for optical-precision composite mirror panels and structures. The deployable mirror is directly applicable to a broad class of non-imaging "lidar" (light direction a nd ranging) telescopes whose figure-error requirements are in the range of one to ten microns RMS. Furthermore, the mirror design can be readily modified to accommodate imaging-quality reflector panels and active panel-alignment control mechanisms for application to imaging telescopes. The present paper: 1) describes the deployable mirror concept; 2) explains the status of the mirror development; and 3) provides some technical specifications for a 2.55- m-diameter, proof-of-concept mirror. Keywords: precision deployment, hinge joint, latch joint, deployable structures, fabrication, space telescopes, optical instruments, microdynamics.

  15. Wavefront Analysis of Adaptive Telescope

    NASA Technical Reports Server (NTRS)

    Hadaway, James B.; Hillman, Lloyd

    1997-01-01

    The motivation for this work came from a NASA Headquarters interest in investigating design concepts for a large space telescope employing active optics technology. The development of telescope optical requirements and potential optical design configurations is reported.

  16. Beyond 31 mag arcsec-2: The Frontier of Low Surface Brightness Imaging with the Largest Optical Telescopes

    NASA Astrophysics Data System (ADS)

    Trujillo, Ignacio; Fliri, Jüergen

    2016-06-01

    The detection of structures in the sky with optical surface brightnesses fainter than 30 mag arcsec-2 (3σ in 10 × 10 arcsec boxes; r-band) has remained elusive in current photometric deep surveys. Here we show how present-day telescopes of 10 m class can provide broadband imaging 1.5-2 mag deeper than most previous results within a reasonable amount of time (i.e., <10 hr on-source integration). In particular, we illustrate the ability of the 10.4 m Gran Telescopio de Canarias telescope to produce imaging with a limiting surface brightness of 31.5 mag arcsec-2 (3σ in 10 × 10 arcsec boxes; r-band) using 8.1 hr on source. We apply this power to explore the stellar halo of the galaxy UGC 00180, a galaxy analogous to M31 located at ˜150 Mpc, by obtaining a radial profile of surface brightness down to μ r ˜ 33 mag arcsec-2. This depth is similar to that obtained using the star-counts techniques for Local Group galaxies, but is achieved at a distance where this technique is unfeasible. We find that the mass of the stellar halo of this galaxy is ˜4 × 109 M ⊙, i.e., (3 ± 1)% of the total stellar mass of the whole system. This amount of mass in the stellar halo is in agreement with current theoretical expectations for galaxies of this kind.

  17. Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST)

    NASA Astrophysics Data System (ADS)

    Baldauf, Brian; Conti, Alberto

    2016-01-01

    The "Search for Life" via imaging of exoplanets is a mission that requires extremely stable telescopes with apertures in the 10 m to 20 m range. The High Definition Space Telescope (HDST) envisioned for this mission would have an aperture >10 m, which is a larger payload than what can be delivered to space using a single launch vehicle. Building and assembling the mirror segments enabling large telescopes will likely require multiple launches and assembly in space. Space-based telescopes with large apertures will require major changes to system architectures.The Optical Telescope Assembly (OTA) for HDST is a primary mission cost driver. Enabling and affordable solutions for this next generation of large aperture space-based telescope are needed.This paper reports on the concept for the Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST), which demonstrates on-orbit robotic and/or astronaut assembly of a precision optical telescope in space. It will also facilitate demonstration of active correction of phase and mirror shape. MODEST is proposed to be delivered to the ISS using standard Express Logistics Carriers (ELCs) and can mounted to one of a variety of ISS pallets. Post-assembly value includes space, ground, and environmental studies, and a testbed for new instruments. This demonstration program for next generation mirror technology provides significant risk reduction and demonstrates the technology in a six-mirror phased telescope. Other key features of the demonstration include the use of an active primary optical surface with wavefront feedback control that allows on-orbit optimization and demonstration of precise surface control to meet optical system wavefront and stability requirements.MODEST will also be used to evaluate advances in lightweight mirror and metering structure materials such as SiC or Carbon Fiber Reinforced Polymer that have excellent mechanical and thermal properties, e.g. high stiffness, high modulus, high thermal

  18. Uzaybimer Radio Telescope Control System

    NASA Astrophysics Data System (ADS)

    Balbay, R.; Öz, G. K.; Arslan, Ö.; Özeren, F. F.; Küçük, İ.

    2016-12-01

    A 13 meters former NATO radar is being converted into a radio telescope. The radio telescope is controlled by a system which has been developed at UZAYBİMER. The Telescope Control System(TCS) has been designed using modern industrial systems. TCS has been developed in LabView platform in which works Windows embedded OS. The position feedback used on radio telescopes is an industrial EtherCAT standard. ASCOM library is used for astronomical calculations.

  19. The Primeval Structure Telescope

    NASA Astrophysics Data System (ADS)

    Peterson, J. B.; Pen, U. L.; Wu, X. P.

    2004-12-01

    The Primeval Structure Telescope (PaST) will be used to study early ionization of the universe. The telescope will image and spectrally resolve hyperfine emission of neutral hydrogen at redshifts from about 6 to 20. Recently released data, obtained with the WMAP satellite, indicate that the universe was ionized very early, at around redshift 15. Right now, there is very little information on this ionization, since the WMAP data do not tell us the ionization history or the energy source. If the energy source was emission from collapsed objects, perhaps ultraviolet radiation from the first stars, the ionization did not occur homogenously. Earlier star formation in high-density regions causes these to be ionized first. Just when the ionization was half complete, the large-scale structure of the universe became visible in the ionization pattern. We will use redshifted 21 cm brightness to image the largest of the ionized bubbles in three dimensions, allowing us to determine the redshift of the early ionization. In addition, we will be able to study the evolution and merging of the ionized bubbles. PAST will be a sparse array telescope consisting of 10,000 log periodic antennas, providing over 50,000 square meters of effective collecting area. These antennas will be grouped into 80 phased arrays of 127 antennas. Current plans have these phased arrays fixed, pointed at the North Celestial Pole. Later, we can add electronic beam steering. Signals from the 80 phased arrays will be processed using a correlator built from a network of about 100 PC computers. The telescope will occupy ten square kilometers in the Ulastai Valley, Xin Jiang, China. The telescope will be built almost entirely of inexpensive commercially available off-the-shelf components. A series of tests of prototypes, made on-site, have allowed us to study the performance of the telescope and its components. We will present these results and show sky images obtained with the prototypes. We anticipate that one

  20. Comparisons of Monthly Mean 10 M Wind Speeds from Satellites and NWP Products Over the Global Ocean

    DTIC Science & Technology

    2009-10-09

    Resolution QSCAT SSM/I NOGAPS ERA-40 NCEP Sea Winds instrument on the Quick Scatterometer Special Sensor Microwave/Imager Navy Operational...measurements with 25-point smoothing as described earlier. [25] Within the latitudes spanning the Arctic and Antarctic , no ice mask is applied in order to...ET AL.: 10 M WINDS OVER THE GLOBAL OCEAN D16109 egies that blend two or more of these products to produce improved forcing fields. [53

  1. 17 CFR 249.510 - Form 10-M, consent to service of process by a nonresident general partner of a broker-dealer firm.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 17 Commodity and Securities Exchanges 3 2011-04-01 2011-04-01 false Form 10-M, consent to service... ACT OF 1934 Forms for Statements Made in Connection With Exempt Tender Offers § 249.510 Form 10-M... Note: For Federal Register citations affecting Form 10-M, see the List of CFR Sections Affected,...

  2. Structures and Stabilities of the Metal Doped Gold Nano-Clusters: M@Au10 (M = W, Mo, Ru, Co).

    PubMed

    Hossain, Delwar; Pittman, Charles U; Gwaltney, Steven R

    2014-01-01

    The structures and stabilities of a series of endohedral gold clusters containing ten gold atoms M@Au10 (M = W, Mo, Ru, Co) have been determined using density functional theory. The gradient-corrected functional BP86, the Tao-Perdew-Staroverov-Scuseria TPSS meta-GGA functional, and the hybrid density functionals B3LYP and PBE1PBE were employed to calculate the structures, binding energies, adiabatic ionization potentials, and adiabatic electron affinities for these clusters. The LanL2DZ effective core potentials and the corresponding valence basis sets were employed. The M@Au10 (M = W, Mo, Ru, Co) clusters have higher binding energies than an empty Au10 cluster. In addition, the large HOMO-LUMO gaps suggest that the M@Au10 (M = W, Mo, Ru, Co) clusters are all likely to be stable chemically. The ionization potentials and electron affinities for these clusters are very high, and the W@Au10 and Mo@Au10 clusters have electron affinities similar to the super-halogen Al13.

  3. Structures and Stabilities of the Metal Doped Gold Nano-Clusters: M@Au10 (M = W, Mo, Ru, Co)

    PubMed Central

    Hossain, Delwar; Pittman, Charles U.; Gwaltney, Steven R.

    2014-01-01

    The structures and stabilities of a series of endohedral gold clusters containing ten gold atoms M@Au10 (M = W, Mo, Ru, Co) have been determined using density functional theory. The gradient-corrected functional BP86, the Tao-Perdew-Staroverov-Scuseria TPSS meta-GGA functional, and the hybrid density functionals B3LYP and PBE1PBE were employed to calculate the structures, binding energies, adiabatic ionization potentials, and adiabatic electron affinities for these clusters. The LanL2DZ effective core potentials and the corresponding valence basis sets were employed. The M@Au10 (M = W, Mo, Ru, Co) clusters have higher binding energies than an empty Au10 cluster. In addition, the large HOMO–LUMO gaps suggest that the M@Au10 (M = W, Mo, Ru, Co) clusters are all likely to be stable chemically. The ionization potentials and electron affinities for these clusters are very high, and the W@Au10 and Mo@Au10 clusters have electron affinities similar to the super-halogen Al13. PMID:24611036

  4. Lunar transit telescope lander design

    NASA Technical Reports Server (NTRS)

    Omar, Husam A.

    1991-01-01

    The Program Development group at NASA's Marshall Space Flight Center has been involved in studying the feasibility of placing a 16 meter telescope on the lunar surface to scan the skies using visible/ Ultraviolet/ Infrared light frequencies. The precursor telescope is now called the TRANSIT LUNAR TELESCOPE (LTT). The Program Development Group at Marshall Space Flight Center has been given the task of developing the basic concepts and providing a feasibility study on building such a telescope. The telescope should be simple with minimum weight and volume to fit into one of the available launch vehicles. The preliminary launch date is set for 2005. A study was done to determine the launch vehicle to be used to deliver the telescope to the lunar surface. The TITAN IV/Centaur system was chosen. The engineering challenge was to design the largest possible telescope to fit into the TITAN IV/Centaur launch system. The telescope will be comprised of the primary, secondary and tertiary mirrors and their supporting system in addition to the lander that will land the telescope on the lunar surface and will also serve as the telescope's base. The lunar lander should be designed integrally with the telescope in order to minimize its weight, thus allowing more weight for the telescope and its support components. The objective of this study were to design a lander that meets all the constraints of the launching system. The basic constraints of the TITAN IV/Centaur system are given.

  5. Lunar transit telescope lander design

    NASA Technical Reports Server (NTRS)

    Omar, Husam A.

    1992-01-01

    The Program Development group at NASA's Marshall Space Flight Center has been involved in studying the feasibility of placing a 16 meter telescope on the lunar surface to scan the skies using visible/ Ultraviolet/ Infrared light frequencies. The precursor telescope is now called the TRANSIT LUNAR TELESCOPE (LTT). The Program Development Group at Marshall Space Flight Center has been given the task of developing the basic concepts and providing a feasibility study on building such a telescope. The telescope should be simple with minimum weight and volume to fit into one of the available launch vehicles. The preliminary launch date is set for 2005. A study was done to determine the launch vehicle to be used to deliver the telescope to the lunar surface. The TITAN IV/Centaur system was chosen. The engineering challenge was to design the largest possible telescope to fit into the TITAN IV/Centaur launch system. The telescope will be comprised of the primary, secondary and tertiary mirrors and their supporting system in addition to the lander that will land the telescope on the lunar surface and will also serve as the telescope's base. The lunar lander should be designed integrally with the telescope in order to minimize its weight, thus allowing more weight for the telescope and its support components. The objective of this study were to design a lander that meets all the constraints of the launching system. The basic constraints of the TITAN IV/Centaur system are given.

  6. Science operations with Space Telescope

    NASA Technical Reports Server (NTRS)

    Giacconi, R.

    1982-01-01

    The operation, instrumentation, and expected contributions of the Space Telescope are discussed. Space Telescope capabilities are described. The organization and nature of the Space Telescope Science Institute are outlined, including the allocation of observing time and the data rights and data access policies of the institute.

  7. Lowell Observatory's Discovery Channel Telescope

    NASA Astrophysics Data System (ADS)

    Hall, Jeffrey C.

    2017-01-01

    Lowell Observatory broke ground on its 4.3-meter Discovery Channel Telescope (DCT) in July 2005 and celebrated first light for the telescope in July 2012. In this overview to this special session, I will discuss the origin and development of the project, the telescope's general specifications and performance, its current operating status, and the initial instrument suite.

  8. The single mirror small size telescope (SST-1M) of the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Aguilar, J. A.; Bilnik, W.; Borkowski, J.; Cadoux, F.; Christov, A.; della Volpe, D.; Favre, Y.; Heller, M.; Kasperek, J.; Lyard, E.; Marszałek, A.; Moderski, R.; Montaruli, T.; Porcelli, A.; Prandini, E.; Rajda, P.; Rameez, M.; Schioppa, E., Jr.; Troyano Pujadas, I.; Zietara, K.; Blocki, J.; Bogacz, L.; Bulik, T.; Frankowski, A.; Grudzinska, M.; Idźkowski, B.; Jamrozy, M.; Janiak, M.; Lalik, K.; Mach, E.; Mandat, D.; Michałowski, J.; Neronov, A.; Niemiec, J.; Ostrowski, M.; Paśko, P.; Pech, M.; Schovanek, P.; Seweryn, K.; Skowron, K.; Sliusar, V.; Stawarz, L.; Stodulska, M.; Stodulski, M.; Toscano, S.; Walter, R.; WiÈ©cek, M.; Zagdański, A.

    2016-07-01

    The Small Size Telescope with Single Mirror (SST-1M) is one of the proposed types of Small Size Telescopes (SST) for the Cherenkov Telescope Array (CTA). The CTA south array will be composed of about 100 telescopes, out of which about 70 are of SST class, which are optimized for the detection of gamma rays in the energy range from 5 TeV to 300 TeV. The SST-1M implements a Davies-Cotton optics with a 4 m dish diameter with a field of view of 9°. The Cherenkov light produced in atmospheric showers is focused onto a 88 cm wide hexagonal photo-detection plane, composed of 1296 custom designed large area hexagonal silicon photomultipliers (SiPM) and a fully digital readout and trigger system. The SST-1M camera has been designed to provide high performance in a robust as well as compact and lightweight design. In this contribution, we review the different steps that led to the realization of the telescope prototype and its innovative camera.

  9. ALMA telescope reaches new heights

    NASA Astrophysics Data System (ADS)

    2009-09-01

    the electromagnetic spectrum. Light at these wavelengths comes from some of the coldest, but also from some of the most distant objects in the cosmos. These include cold clouds of gas and dust where new stars are being born and remote galaxies towards the edge of the observable universe. The Universe is relatively unexplored at submillimetre wavelengths, as the telescopes need extremely dry atmospheric conditions, such as those at Chajnantor, and advanced detector technology. More information The Atacama Large Millimeter/submillimeter Array (ALMA), an international astronomy facility, is a partnership of Europe, North America and East Asia in cooperation with the Republic of Chile. ESO is the European partner in ALMA. ALMA, the largest astronomical project in existence, is a revolutionary telescope, comprising an array of 66 giant 12-metre and 7-metre diameter antennas observing at millimetre and submillimetre wavelengths. ALMA will start scientific observations in 2011. ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a

  10. The Bionic Telescope

    NASA Astrophysics Data System (ADS)

    Woolf, Neville

    2009-05-01

    Four hundred years after children in a spectacle makers workshop accidentally discovered the telescope, the development of this device has been a continuous replacement of the ``natural'' by the deliberate. The human eye is gone. The lens is gone. The tube is gone. The dome is on the verge of going. The size of the optics are ceasing to be set by transportation limits. Adaptive optics are preferred to stable optics. We deliberately break the Lagrange invariant. We focus on lasers instead of stars, and natural observing environments are being replaced by adaptive environments. The goals for the new ground based telescope encompass the oldest and newest ideas, to find signs of life elsewhere, and to find how all the universe developed.

  11. Origins Space Telescope

    NASA Astrophysics Data System (ADS)

    Cooray, Asantha R.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its spectrographs will enable 3D surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. I will summarize the OST STDT, mission design and instruments, key science drivers, and the study plan over the next two years.

  12. Telescopic limiting magnitudes

    NASA Technical Reports Server (NTRS)

    Schaefer, Bradley E.

    1990-01-01

    The prediction of the magnitude of the faintest star visible through a telescope by a visual observer is a difficult problem in physiology. Many prediction formulas have been advanced over the years, but most do not even consider the magnification used. Here, the prediction algorithm problem is attacked with two complimentary approaches: (1) First, a theoretical algorithm was developed based on physiological data for the sensitivity of the eye. This algorithm also accounts for the transmission of the atmosphere and the telescope, the brightness of the sky, the color of the star, the age of the observer, the aperture, and the magnification. (2) Second, 314 observed values for the limiting magnitude were collected as a test of the formula. It is found that the formula does accurately predict the average observed limiting magnitudes under all conditions.

  13. Telescopes of galileo.

    PubMed

    Greco, V; Molesini, G; Quercioli, F

    1993-11-01

    The Florentine Istituto e Museo di Storia delta Scienza houses two complete telescopes and a single objective lens (reconstructed from several fragments) that can be attributed to Galileo. These optics have been partially dismantled and made available for optical testing with state-of-the-art equipment. The lenses were investigated individually; the focal length and the radii of curvature were measured, and the optical layout of the instruments was worked out. The optical quality of the surfaces and the overall performance of the two complete telescopes have been evaluated interferometrically at a wavelength of 633 nm (with a He-Ne laser source). It was found in particular that the optics of Galileo came close to attaining diffraction-limited operation.

  14. Galileo's wondrous telescope

    NASA Astrophysics Data System (ADS)

    Cartlidge, Edwin

    2008-06-01

    If you need reminding of just how wrong the great and the good can be, take a trip to the Museum of the History of Science in Florence, Italy. The museum is staging an exhibition entitled "Galileo's telescope - the instrument that changed the world" to mark the 400th anniversary this year of Galileo Galilei's revolutionary astronomical discoveries, which were made possible by the invention of the telescope. At the start of the 17th century, astronomers assumed that all the planets and the stars in the heavens had been identified and that there was nothing new for them to discover, as the exhibition's curator, Giorgio Strano, points out. "No-one could have imagined what wondrous new things were about to be revealed by an instrument created by inserting two eyeglass lenses into the ends of a tube," he adds.

  15. Telescopic horizon scanning.

    PubMed

    Koenderink, Jan

    2014-12-20

    The problem of "distortionless" viewing with terrestrial telescopic systems (mainly "binoculars") remains problematic. The so called "globe effect" is only partially counteracted in modern designs. Theories addressing the phenomenon have never reached definitive closure. In this paper, we show that exact distortionless viewing with terrestrial telescopic systems is not possible in general, but that it is in principle possible in-very frequent in battle field and marine applications-the case of horizon scanning. However, this involves cylindrical optical elements. For opto-electronic systems, a full solution is more readily feasible. The solution involves a novel interpretation of the relevant constraints and objectives. For final design decisions, it is not necessary to rely on a corpus of psychophysical (or ergonomic) data, although one has to decide whether the instrument is intended as an extension of the eye or as a "pictorial" device.

  16. Nonmechanical bifocal zoom telescope.

    PubMed

    Valley, Pouria; Reza Dodge, Mohammad; Schwiegerling, Jim; Peyman, Gholam; Peyghambarian, N

    2010-08-01

    We report on a novel zoom lens with no moving parts in the form of a switchable Galilean telescope. This zoom telescope consists of two flat liquid-crystal diffractive lenses with apertures of 10mm that can each take on the focal lengths of -50 and +100cm, with a spacing of 50cm and, hence, a zoom ratio of 4x. The lenses are driven using a low-voltage ac source with 1.6V and exhibit millisecond switching times. The spectral characteristic of this diffractive zoom system is evaluated for light sources of various bandwidths. Potential applications for this technology include a zoom lens with no moving parts for camera phones and medical imaging devices.

  17. TAUVEX - UV Space Telescope

    NASA Astrophysics Data System (ADS)

    Topaz, Jeremy; Braun, Ofer; Brosch, Noah

    1993-01-01

    The TAUVEX UV Space Telescope currently under construction by El-Op Ltd. in Israel is designed both for recording images of the sky in the UV region and to serve as the optical monitor for the SODART X-Ray Telescope being built by the Danish Space Research Institute. The two systems, together with several other experiments, will be flown on the S-R-G satellite to be launched by the CIS in 1995. TAUVEX will image a field of about 1 deg simultaneously in three spectral bands. In addition, it will record a selected object in a high-speed time-resolved mode in these bands. The concept and design of TAUVEX is described in this paper.

  18. The Neutrino Telescope ANTARES

    NASA Astrophysics Data System (ADS)

    Hernández, Juan José

    Neutrinos can reveal a brand new Universe at high energies. The ANTARES collaboration [1] , formed in 1996, works towards the building and deployment of a neutrino telescope. This detector could observe and study high energy astrophysical sources such as X-ray binary systems, young supernova remnants or Active Galactic Nuclei and help to discover or set exclusion limits on some of the elementary particles and objects that have been put forward as candidates to fill the Universe (WIMPS, neutralinos, topological deffects, Q-balls, etc). A neutrino telescope will certainly open a new observational window and can shed light on the most energetic phenomena of the Universe. A review of the progress made by the ANTARES collaboration to achieve this goal is presented

  19. A New Generation of Sub Mm Telescopes, Made of Carbon Fiber Reinforced Plastic

    NASA Technical Reports Server (NTRS)

    Mezger, P.; Baars, J. W. M.; Ulich, B. L.

    1984-01-01

    Carbon fiber reinforced plastic (CFRP) appears to be the material most suited for the construction of submillimeter telescopes (SMT) not only for ground-based use but also for space applications. The accuracy of the CFRP reflectors needs to be improved beyond value of the 17 micron rms envisaged for the 10 m SMT.

  20. [Galileo and his telescope].

    PubMed

    Strebel, Christoph

    2006-01-01

    Galileo's publication of observations made with his newly reinvented telescope provoked a fierce debate. In April 1610 Martinus Horky, a young Bohemian astronomer, had an opportunity to make his own observations with Galileo's telescope in the presence of Antonio Magini and other astronomers. Horky and the other witnesses denied the adequacy of Galileo's telescope and therefore the bona fides of his discoveries. Kepler conjectured Horky as well as all his witnesses to be myopic. But Kepler's objection could not stop the publication of Horky's Peregrinatio contra nuncium sidereum (Modena, 1610), the first printed refutation of Galileo's Sidereus nuncius. In his treatise, Horky adresses four questions: 1) Do the four newly observed heavenly bodies actually exist? Horky denies their existence on various grounds: a) God, as every astronomer teaches, has created only seven moveable heavenly bodies and astronomical knowledge originates in God, too. b) Heavenly bodies are either stars or planets. Galileo's moveable heavenly bodies fit into neither category. c) If they do exist, why have they not already been observed by other scholars? Horky concludes that there are no such heavenly bodies. 2) What are these phenomena? They are purely artefactual, and produced by Galileo's telescope. 3) How are they like? Galileo's "stars" are so small as to be almost invisible. Galileo claims that he has measured their distances from each other. This however is impossible due to their diminutive size and other observational problems. Hence, Galileo's claim is a further proof that he is a fraud. 4) Why are they? For Galileo they are a chance to earn money but for astronomers like Horky they are a reason to offer thanks and honour to God. Horky's treatise was favourably received by the enemies of Galileo. But Kepler's critique was devastating. After calling on Kepler in Prague, Horky had to revoke the contents of his book.

  1. The Large Area Telescope

    SciTech Connect

    Michelson, Peter F.; /KIPAC, Menlo Park /Stanford U., HEPL

    2007-11-13

    The Large Area Telescope (LAT), one of two instruments on the Gamma-ray Large Area Space Telescope (GLAST) mission, is an imaging, wide field-of-view, high-energy pair-conversion telescope, covering the energy range from {approx}20 MeV to more than 300 GeV. The LAT is being built by an international collaboration with contributions from space agencies, high-energy particle physics institutes, and universities in France, Italy, Japan, Sweden, and the United States. The scientific objectives the LAT will address include resolving the high-energy gamma-ray sky and determining the nature of the unidentified gamma-ray sources and the origin of the apparently isotropic diffuse emission observed by EGRET; understanding the mechanisms of particle acceleration in celestial sources, including active galactic nuclei, pulsars, and supernovae remnants; studying the high-energy behavior of gamma-ray bursts and transients; using high-energy gamma-rays to probe the early universe to z {ge} 6; and probing the nature of dark matter. The components of the LAT include a precision silicon-strip detector tracker and a CsI(Tl) calorimeter, a segmented anticoincidence shield that covers the tracker array, and a programmable trigger and data acquisition system. The calorimeter's depth and segmentation enable the high-energy reach of the LAT and contribute significantly to background rejection. The aspect ratio of the tracker (height/width) is 0.4, allowing a large field-of-view and ensuring that nearly all pair-conversion showers initiated in the tracker will pass into the calorimeter for energy measurement. This paper includes a description of each of these LAT subsystems as well as a summary of the overall performance of the telescope.

  2. Hubble Space Telescope satellite

    NASA Technical Reports Server (NTRS)

    Mitchell, R. E.

    1985-01-01

    The Hubble Space Telescope, named for the American astronomer Edwin Powell Hubble, will be the largest and most powerful astronomical instrument ever orbited. Placed above the obscuring effects of the earth's atmosphere in a 600-km orbit, this remotely-controlled, free-flying satellite observatory will expand the terrestrial-equivalent resolution of the universe by a factor of seven, or a volumetric factor of 350. This telescope has a 2.4-m primary mirror and can accommodate five scientific instruments (cameras, spectrographs and photometers). The optics are suitable for a spectral range from 1100 angstrom to 1 mm wavelength. With a projected service life of fifteen years, the spacecraft can be serviced on-orbit for replacement of degraded systems, to insert advanced scientific instruments, and to reboost the telescope from decayed altitudes. The anticipated image quality will be a result of extremely precise lambda/20 optics, stringent cleanliness, and very stable pointing: jitter will be held to less than 0.01 arcsecond for indefinite observation periods, consistent with instrument apertures as small as 0.1 arcsecond.

  3. "Racializing" Class

    ERIC Educational Resources Information Center

    Hatt-Echeverria, Beth; Urrieta, Luis, Jr.

    2003-01-01

    In an effort to explore how racial and class oppressions intersect, the authors use their autobiographical narratives to depict cultural and experiential continuity and discontinuity in growing up white working class versus Chicano working class. They specifically focus on "racializing class" due to the ways class is often used as a copout by…

  4. Nearby active galactic nuclei seen via adaptive optics at the Keck Telescope

    NASA Astrophysics Data System (ADS)

    Max, Claire

    2004-02-01

    In recent years it has become increasingly clear that mergers between galaxies play a critical role in galaxy evolution, in the formation of central black holes, and in the phenomena of active galactic nuclei (AGNs) and quasar activity. The advent of adaptive optics on the new generation of 6-10 m telescopes is making it possible to study nearby AGNs and merging galaxies with spatial resolutions of10 - 100 pc. In this talk I will describe and discuss observations of NGC 6240 and Cygnus A, archetypes of merging disk galaxies and of powerful radiogalaxies respectively. I will make use of infrared observations using the adaptive optics system on the 10-m Keck Telescope, as well as visible-light observations from the Hubble Space Telescope.

  5. Comparing NEO Search Telescopes

    NASA Astrophysics Data System (ADS)

    Myhrvold, Nathan

    2016-04-01

    Multiple terrestrial and space-based telescopes have been proposed for detecting and tracking near-Earth objects (NEOs). Detailed simulations of the search performance of these systems have used complex computer codes that are not widely available, which hinders accurate cross-comparison of the proposals and obscures whether they have consistent assumptions. Moreover, some proposed instruments would survey infrared (IR) bands, whereas others would operate in the visible band, and differences among asteroid thermal and visible-light models used in the simulations further complicate like-to-like comparisons. I use simple physical principles to estimate basic performance metrics for the ground-based Large Synoptic Survey Telescope and three space-based instruments—Sentinel, NEOCam, and a Cubesat constellation. The performance is measured against two different NEO distributions, the Bottke et al. distribution of general NEOs, and the Veres et al. distribution of Earth-impacting NEO. The results of the comparison show simplified relative performance metrics, including the expected number of NEOs visible in the search volumes and the initial detection rates expected for each system. Although these simplified comparisons do not capture all of the details, they give considerable insight into the physical factors limiting performance. Multiple asteroid thermal models are considered, including FRM, NEATM, and a new generalized form of FRM. I describe issues with how IR albedo and emissivity have been estimated in previous studies, which may render them inaccurate. A thermal model for tumbling asteroids is also developed and suggests that tumbling asteroids may be surprisingly difficult for IR telescopes to observe.

  6. The Planck Telescope reflectors

    NASA Astrophysics Data System (ADS)

    Stute, Thomas

    2004-09-01

    The mechanical division of EADS-Astrium GmbH, Friedrichshafen is currently engaged with the development, manufacturing and testing of the advanced dimensionally stable composite reflectors for the ESA satellite borne telescope Planck. The objective of the ESA mission Planck is to analyse the first light that filled the universe, the cosmic microwave background radiation. Under contract of the Danish Space Research Institute and ESA EADS-Astrium GmbH is developing the all CFRP primary and secondary reflectors for the 1.5-metre telescope which is the main instrument of the Planck satellite. The operational frequency ranges from to 25 GHz to 1000 GHz. The demanding high contour accuracy and surface roughness requirements are met. The design provides the extreme dimensional stability required by the cryogenic operational environment at around 40 K. The elliptical off-axis reflectors display a classical lightweight sandwich design with CFRP core and facesheets. Isostatic mounts provide the interfaces to the telescope structure. Protected VDA provides the reflecting surface. The manufacturing is performed at the Friedrichshafen premises of EADS-Space Transportation GmbH, the former Dornier composite workshops. Advanced manufacturing technologies like true angle lay-up by CNC fibre placement and filament winding are utilized. The protected coating is applied at the CAHA facilities at the Calar Alto Observatory, Spain. The exhaustive environmental testing is performed at the facilities of IABG, Munich (mechanical testing) and for the cryo-optical tests at CSL Liege. The project is in advanced state with both Qualification Models being under environmental testing. The flight models will be delivered in 2004. The paper gives an overview over the requirements and the main structural features how these requirements are met. Special production aspects and available test results are reported.

  7. Is Your Telescope Tweeting?

    NASA Astrophysics Data System (ADS)

    Atkinson, Nancy

    2009-05-01

    Half of the world's population today was born after the Apollo Moon landings. The best way to reach this generation and get them excited about today's space exploration and astronomy news and events is through online social media, which are technologies that allow anyone to communicate with everyone. Twitter is a growing popular social media tool that uses short, 140 character "Tweets" to quickly and concisely convey updates on what you "are doing." With the right combination of information, personality and fun, telescopes and spacecraft are using Twitter for public outreach, providing important status updates while making the public feel like they are part of the mission.

  8. SST dual-mirror telescopes for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Dumas, Delphine; Laporte, Philippe; Sol, Hélène; Pareschi, Giovanni; Canestrari, Rodolfo; Stringhetti, Luca; Catalano, Osvaldo; White, Richard; Greenshaw, Tim; Hinton, Jim; Blake, Simon

    2014-07-01

    The Cherenkov Telescope Array (CTA) is an international collaboration that aims to create the world's foremost very high energy gamma-ray observatory, composed of large, medium and small size telescopes (SST). The SSTs will be the most numerous telescopes on site and will focus on capturing the rarer highest energy photons. Three prototypes of SST are designed and currently under construction; two of them, ASTRI and SST-GATE, have been designed, based on a dual-mirror Schwarzschild-Couder (SC) design which has never been built before for any astronomical observation. The SC optical design allows for a small plate scale, a wide field of view and a lightweight cameras aiming to minimize the cost of SST telescopes in order to increase their number in the array. The aim of this article is to report the progress of the two telescope projects prototyping telescope structures and cameras for the Small Size Telescopes for CTA. After a discussion of the CTA project and its scientific objectives, the performance of the SC design is described, with focus on the specific designs of SST-GATE and ASTRI telescopes. The design of both prototypes and their progress is reported in the current prototyping phase. The designs of Cherenkov cameras, CHEC and ASTRI, to be mounted on these telescopes are discussed and progresses are reported.

  9. High incidence of interleukin 10 mRNA but not interleukin 2 mRNA detected in human breast tumours.

    PubMed Central

    Venetsanakos, E.; Beckman, I.; Bradley, J.; Skinner, J. M.

    1997-01-01

    Despite the presence of a lymphocytic infiltrate in solid cancers, the failure for tumour growth to be contained suggests an inadequate immune response to the tumour. Poor cytotoxicity exerted by tumour-infiltrating lymphocytes (TILs) against tumour cells in vitro, combined with continued tumour growth in vivo, suggests deficiencies in TIL function or numbers. Various theories have been postulated to explain how tumour cells may escape immunosurveillance and control. One of the many hypotheses is the failure of production of cytokines, which are necessary for T cells to mediate their function. Thus, the expression of cytokine mRNA in human breast tumour sections was investigated by reverse transcriptase polymerase chain reaction (RT-PCR) with cytokine-specific primers. A relatively consistent finding was detection of interleukin (IL) 10 mRNA among the tumours. No IL-2 and little IL-4 mRNA was detected in the tumours. IL-6 and IL-10 mRNA was detected in only one and two of the normal breast tissues respectively. IL-2, IL-4 and tumour necrosis factor (TNF)-alpha mRNA was not detected in any of the normal breast tissues. The reduced function of TILs may be related to IL-10, which has known inhibitory effects on T-cell activation. Images Figure 1 PMID:9192989

  10. MeV electron acceleration at 1 kHz with <10 mJ laser pulses

    NASA Astrophysics Data System (ADS)

    Salehi, Fatholah; Goers, Andy; Hine, George; Feder, Linus; Kuk, Donghoon; Miao, Bo; Woodbury, Daniel; Kim, Ki-Yong; Milchberg, Howard

    2017-01-01

    We demonstrate laser driven acceleration of electrons to MeV-scale energies at 1 kHz repetition rate using <10 mJ pulses focused on near-critical density He and H2 gas jets. Using the H2 gas jet, electron acceleration to 0.5 MeV in 10 fC bunches was observed with laser pulse energy as low as 1.3 mJ. Increasing the pulse energy to 10 mJ, we measure 1pC charge bunches with >1 MeV energy for both He and H gas jets. Such a high repetition rate, high flux ultrafast source has immediate application to time resolved probing of matter for scientific, medical, or security applications, either using the electrons directly or using a high-Z foil converter to generate ultrafast γ-rays. This work is supported by the US Department of Energy, the National Science Foundation, and the Air Force Office of Scientific Research.

  11. Performance of the Gamma-ray Cherenkov Telescope structure: a dual-mirror telescope prototype proposed for the future Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Dournaux, J. L.; Amans, J. P.; Dangeon, L.; Fasola, G.; Gironnet, J.; Huet, J. M.; Laporte, P.; Abchiche, A.; Barkaoui, S.; Bousquet, J. J.; Buchholtz, G.; Dumas, D.; Gaudemard, J.; Jégouzo, I.; Poinsignon, P.; Vergne, L.; Sol, H.

    2016-07-01

    The Cherenkov Telescope Array (CTA) project aims to create the next generation Very High-Energy (VHE) gamma-ray telescope array. It will be devoted to the observation of gamma rays from 20 GeV to above 100 TeV. Because of this wide energy band, three classes of telescopes, associated with different energy ranges and different mirror sizes, are defined. The Small Size Telescopes (SSTs) are associated with the highest energy range. Seventy of these telescopes are foreseen on the Southern site of the CTA. The large number of telescopes constrains their mechanical structure because easy maintenance and reduced cost per telescope are needed. Moreover, of course, the design shall fulfill the required performance and lifetime in the environment conditions of the site. The Observatoire de Paris started design studies in 2011 of the mechanical structure of the GCT (Gamma-ray Cherenkov Telescope), a four-meter prototype telescope for the SSTs of CTA, from optical and preliminary mechanical designs made by the University of Durham. At the end of 2014 these studies finally resulted in a lightweight ( 8 tons) and stiff design. This structure was based on the dual-mirror Schwarzschild-Couder (SC) optical design, which is an interesting and innovative alternative to the one-mirror Davies-Cotton design commonly used in ground-based Cherenkov astronomy. The benefits of such a design are many since it enables a compact structure, lightweight camera and a good angular resolution across the entire field-of-view. The mechanical structure was assembled on the Meudon site of the Observatoire de Paris in spring 2015. The secondary mirror, panels of the primary mirror and the Telescope Control System were successfully implemented afterwards leading now to a fully operational telescope. This paper focuses on the mechanics of the telescope prototype. It describes the mechanical structure and presents its performance identified from computations or direct measurements. Upgrades of the design

  12. Novel In-Space Manufacturing Concepts for the Development of Large Space Telescopes

    NASA Technical Reports Server (NTRS)

    Mooney, James T.; Reardon, Patrick; Gregory Don; Manning, Andrew; Blackmon, Jim; Howsman, Tom; Williams, Philip; Brantley, Whitt; Rakoczy, John; Herren, Kenneth

    2006-01-01

    There is a continuous demand for larger, lighter, and higher quality telescopes. Over the past several decades, we have seen the evolution from launchable 2 meter-class telescopes (such as Hubble), to today s demand for deployable 6 meter-class telescopes (such as JWST), to tomorrow s need for up to 150 meter-class telescopes. As the apertures continue to grow, it will become much more difficult and expensive to launch assembled telescope structures. To address this issue, we are seeing the emergence of new novel structural concepts, such as inflatable structures and membrane optics. While these structural concepts do show promise, it is very difficult to achieve and maintain high surface figure quality. Another potential solution to develop large space telescopes is to move the fabrication facility into space and launch the raw materials. In this paper we present initial in-space manufacturing concepts to enable the development of large telescopes. This includes novel approaches for the fabrication of both the optical elements and the telescope support structure. We will also discuss potential optical designs for large space telescopes and describe their relation to the fabrication methods. These concepts are being developed to meet the demanding requirements of DARPA s LASSO (Large Aperture Space Surveillance Optic) program which currently requires a 150 meter optical aperture with a 17 degree field of view.

  13. Ares V Launch Capability Enables Future Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2007-01-01

    NASA's Ares V cargo launch vehicle offers the potential to completely change the paradigm of future space science mission architectures. A major finding of the NASA Advanced Telescope and Observatory Capability Roadmap Study was that current launch vehicle mass and volume constraints severely limit future space science missions. And thus, that significant technology development is required to package increasingly larger collecting apertures into existing launch shrouds. The Ares V greatly relaxes these constraints. For example, while a Delta IV has the ability to launch approximate a 4.5 meter diameter payload with a mass of 13,000 kg to L2, the Ares V is projected to have the ability to launch an 8 to 12 meter diameter payload with a mass of 60,000 kg to L2 and 130,000 kg to Low Earth Orbit. This paper summarizes the Ares V payload launch capability and introduces how it might enable new classes of future space telescopes such as 6 to 8 meter class monolithic primary mirror observatories, 15 meter class segmented telescopes, 6 to 8 meter class x-ray telescopes or high-energy particle calorimeters.

  14. The CCAT Telescope

    NASA Astrophysics Data System (ADS)

    Glenn, Jason; CCAT

    2013-01-01

    CCAT will be a 25 m diameter on-axis Gregory telescope operating in the 0.2 to 2.1 mm wavelength range. It will be located at an altitude of 5600 m on Cerro Chajnantor in northern Chile. CCAT will support cameras and spectrometers with up to 1 field of view at its f/6 Nasmyth foci. The key performance requirements for the telescope are a half wavefront error <12.5 μm rms and pointing error <0.35"/350 μm). CCAT will have an f/0.4 primary with an active surface to compensate gravitational and thermal deformations. The primary will be made of 2 m keystone-shaped segments, each with 16 machined aluminum tiles mounted on a carbon-fiber-reinforced-plastic (CFRP) subframe. The segments will be supported by a CFRP spaceframe truss on an elevation over azimuth mount made of steel. CCAT will be inside an enclosure to reduce wavefront and pointing errors due to wind forces and thermal deformation due to solar illumination.

  15. The Green Bank Telescope

    NASA Astrophysics Data System (ADS)

    Jewell, P. R.

    1999-12-01

    The Green Bank Telescope The 100-m NRAO Green Bank Telescope will be completed in early 2000. The GBT has a large number of unique design and performance features that will give it unprecedented scientific capability. This poster display will review those features, which include an offset feed (clear aperture) design, an active surface, a closed-loop laser metrology system for surface figure and pointing control, broad frequency coverage from 100 MHz to 115 GHz, a versatile receiver selection mechanism, and a new multi-input, 256k-channel autocorrelation spectrometer. The status of the project, the commissioning schedule, plans for early operations, the initial instrumentation suite, and plans for future instrumentation will be reviewed. Scientific areas for which the GBT will have a large impact will be discussed, including observations of young galaxies at extreme redshifts, pulsars, HI and molecular spectroscopy, VLBI work, and millimeter-wave spectroscopy and continuum studies. The National Radio Astronomy Observatory is a facility of the National Science Foundation, operated under cooperative agreement by Associated Universities, Inc.

  16. Magellan Telescopes operations 2008

    NASA Astrophysics Data System (ADS)

    Osip, David J.; Phillips, Mark M.; Palunas, Povilas; Perez, Frank; Leroy, M.

    2008-07-01

    The twin 6.5m Magellan Telescopes have been in routine operations at the Las Campanas Observatory in the Chilean Andes since 2001 and 2002 respectively. The telescopes are owned and operated by Carnegie for the benefit of the Magellan consortium members (Carnegie Institution of Washington, Harvard University, the University of Arizona, Massachusetts Institute of Technology, and the University of Michigan). This paper provides an up to date review of the scientific, technical, and administrative structure of the 'Magellan Model' for observatory operations. With a modest operations budget and a reasonably small staff, the observatory is operated in the "classical" mode, wherein the visiting observer is a key member of the operations team. Under this model, all instrumentation is supplied entirely by the consortium members and the various instrument teams continue to play a critical support role beyond initial deployment and commissioning activities. Here, we present a critical analysis of the Magellan operations model and suggest lessons learned and changes implemented as we continue to evolve an organizational structure that can efficiently deliver a high scientific return for the investment of the partners.

  17. Near anastigmatic grazing incidence telescope

    NASA Technical Reports Server (NTRS)

    Korsch, D.

    1984-01-01

    A performance capability assessment is presently conducted for short versus long grazing incidence telescope designs, in view of the observation that the field curvature and astigmatism that are the primary residual aberrations of a Wolter-type incidence telescope can be substantially reduced through mirror length reduction. A major advantage of the short element telescope is that, if sufficiently short, both the paraboloid and hyperboloid surfaces may be fabricated as a single piece; this significantly facilitates the task of alignment.

  18. Cost Modeling for Space Telescope

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip

    2011-01-01

    Parametric cost models are an important tool for planning missions, compare concepts and justify technology investments. This paper presents on-going efforts to develop single variable and multi-variable cost models for space telescope optical telescope assembly (OTA). These models are based on data collected from historical space telescope missions. Standard statistical methods are used to derive CERs for OTA cost versus aperture diameter and mass. The results are compared with previously published models.

  19. High-precision robotic equatorial C-ring telescope mounts: design, fabrication, and performance

    NASA Astrophysics Data System (ADS)

    Dubberley, Matthew A.

    2010-07-01

    The performance of the C-ring telescope mount rivals other designs in stiffness, tracking, simplicity, lack of field rotation, mechanical size and operating envelope. Issues relating to cost, fabrication, and complexity have suppressed the prevalence of the C-ring mount. The Las Cumbres Observatory Global Telescope (LCOGT) robotic C-ring telescope mounts, built for its network of 1.0m and 0.4m telescopes, solve many of these issues. The design yields a scalable mount with performance capabilities well suited for telescopes located at the best astronomical sites in the world at a low cost. Pointing has been demonstrated to be under 7 arc-sec RMS. Unguided tracking performance is 0.6 arc-sec for 1 minute and 2 arc-sec for 15 minutes. Slew speeds of 10deg/sec are reliably used with sub-second settling times. The mount coupled with the 1.0m telescope yields a well damped 16 Hz system. Axes are driven with zero backlash direct drive motors with a 0.01 arc-sec resolution. High system bandwidth yields superb disturbance rejection making it ideal for open air operation. Drive and bearings are maintenance free and feature a novel "bug cover" to seal them from wear and damage. Low costs are achieved with the drive/feedback configuration, structure design, and fabrication techniques, as well minimizing operating and maintenance.

  20. CLASS for Class.

    NASA Astrophysics Data System (ADS)

    Bluestein, Howard B.

    1993-09-01

    Faculty and students from the School of Meteorology at the University of Oklahoma and staff members from the Atmospheric Technology Division at the National Center for Atmospheric Research (NCAR) participated in a special course given during the last two weeks of May 1992. The purpose of the course was to give students the opportunity to use the NCAR mobile CLASS (Cross-Chain LORAN Atmospheric Sounding System) in the field and to interpret data they collected themselves in the context of material learned earlier in a lecture setting. Soundings were obtained in parts of Texas and Oklahoma in the environment of multicell storms, in supercells, in a gust front, and on the cold side of a cold front.

  1. Overview of the Nuclear Compton Telescope

    NASA Astrophysics Data System (ADS)

    Perez-Becker, Daniel A.; Liu, Z.; Boggs, S. E.; NCT Collaboration

    2008-03-01

    The Nuclear Compton Telescope (NCT) is a balloon-borne soft gamma-ray (0.2-10 MeV) telescope designed to study astrophysical sources of nuclear line emission and polarization. It consists of twelve high spectral resolution 3D Germanium Detectors that track gamma-ray Compton scatter interactions. Tracking technologies provide dramatic improvements in Compton efficiency and sensitivity: with less than 1% of the detector volume of COMPTEL, NCT achieves a similar effective area. NCT is breaking new ground in the measurement of polarized gamma-ray emission from astrophysical sources, while simultaneously providing a testing platform for novel event analysis, background reduction, and imaging techniques for modern Compton telescopes. NCT is currently being prepared for a 36-hour flight from New Mexico in September 2008, followed by a long duration flight from Australia in December 2009. On these science flights, NCT will map the galactic positron annihilation, Al-26, and Fe-60 emission, and perform a discovery study of polarization from all classes of gamma-ray sources. We will present an overview of the NCT instrument and the planned flight program.

  2. Modular Orbital Demonstration of an Evolvable Space Telescope

    NASA Astrophysics Data System (ADS)

    Baldauf, Brian

    2016-06-01

    The key driver for a telescope's sensitivityis directly related to the size of t he mirror area that collects light from the objects being observed.The "Search for Life" via imaging of exoplanets is a mission that requires extremely stable telescopes with apertures in the 10 m to 20 m range. The HDST envisioned for this mission would have an aperture >10 m, which is a larger payload than can be delivered to space using a single launch vehicle. Building and assembling the mirror segments enabling large telescopes will likely require multiple launches and assembly in space. The Optical Telescope Assembly for HDST is a primary mission cost driver. Enabling affordable solutions for this next generation of large aperture space-based telescope are needed.This reports on the concept for the MODEST, which demonstrates on-orbit robotic and/or astronaut assembly of a precision optical telescope in space. It will facilitate demonstration of active correction of phase and mirror shape. MODEST is proposed to be delivered to the ISS using standard Express Logistics Carriers and can mounted to one of a variety of ISS pallets. Post-assembly value includes space, ground, and environmental studies, a testbed for new instruments, and a tool for student's exploration of space. This demonstration program for next generation mirror technology provides significant risk reduction and demonstrates the technology in a six-mirror phased telescope. Key features of the demonstration include the use of an active primary optical surface with wavefront feedback control that allows on-orbit optimization and demonstration of precise surface control to meet optical system wavefront and stability requirements.MODEST will also be used to evaluate advances in lightweight mirror and metering structure materials such as SiC or Ceramic Matrix Composite that have excellent mechanical and thermal properties, e.g. high stiffness, high thermal conductivity, and low thermal expansion. It has been demonstrated

  3. Single-wavelength coarse phasing in segmented telescopes.

    PubMed

    Simar, J F; Stockman, Y; Surdej, J

    2015-02-10

    Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with larger sizes. The diameters of monolithic primary mirrors are restricted to 10 m because of manufacturing limitations. For space telescopes, the primary mirrors are limited to less than 5 m due to fairing capacity. Segmented primary mirrors thus constitute an alternative solution to deal with the steady increase of primary mirror size. The optical path difference between the individual segments must be close to 0 (a few nanometers) in order to be diffraction-limited. In this paper, we propose a new intersegment piston sensor based on the coherence measurement of a star image. This sensor is intended to be used in the co-phasing system of future segmented mirrors.

  4. Large space telescope, phase A. Volume 3: Optical telescope assembly

    NASA Technical Reports Server (NTRS)

    1972-01-01

    The development and characteristics of the optical telescope assembly for the Large Space Telescope are discussed. The systems considerations are based on mission-related parameters and optical equipment requirements. Information is included on: (1) structural design and analysis, (2) thermal design, (3) stabilization and control, (4) alignment, focus, and figure control, (5) electronic subsystem, and (6) scientific instrument design.

  5. Gamma-Ray Telescopes: 400 Years of Astronomical Telescopes

    NASA Technical Reports Server (NTRS)

    Gehrels, Neil; Cannizzo, John K.

    2010-01-01

    The last half-century has seen dramatic developments in gamma-ray telescopes, from their initial conception and development through to their blossoming into full maturity as a potent research tool in astronomy. Gamma-ray telescopes are leading research in diverse areas such as gamma-ray bursts, blazars, Galactic transients, and the Galactic distribution of Al-26.

  6. SIM.EM-K3 Key comparison of 10 mH inductance standards at 1 kHz

    NASA Astrophysics Data System (ADS)

    Moreno, J. A.; Côté, M.; Koffman, A.; Castro, B. I.; Vasconcellos, R. de Barros e.; Kyriazis, G.; Cazabat, M.; Izquierdo, D.; Faverio, C.; Slomovitz, D.

    2016-01-01

    A key comparison of 10 mH inductance standards at 1 kHz has been carried out with the participation of seven National Metrology Institutes of the Inter-American Metrology System, within the frame of the International Committee for Weights and Measures Mutual Recognition Arrangement (MRA), which was piloted by CENAM, Mexico. Three previously characterized commercial inductors, contained in individual enclosures with controlled temperature were used as traveling standards. This document presents the results and technical details of the comparison. Main text To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the CIPM Mutual Recognition Arrangement (CIPM MRA).

  7. Properties of nanocrystalline Fe75Si15M10 (M-Cr and Al) powders prepared by mechanical alloying.

    PubMed

    Kalita, M P C; Perumal, A; Srinivasan, A; Pandey, Brajesh; Verma, H C

    2008-08-01

    We report the structural and magnetic properties of the nanocrystalline Fe75Si15M10 (M-Al and Cr) powders prepared by mechanical alloying. The milling process produced a non-equilibrium solid solutions of bcc alpha-Fe(Si,Cr) and alpha-Fe(Si,Al). The average dislocation density increases and the average crystallite size decreases with increasing milling time. Magnetic property studies show that the coercivity of the sample increases and magnetization of the sample decreases with increasing milling time. The evolution of a non-equilibrium solid solution and the resulting magnetic properties of nanocrystalline powders are explained on the basis of Neel theory and modified random anisotropy model proposed by Shen et al.

  8. Integrated Laboratory Demonstrations of Multi-Object Adaptive Optics on a Simulated 10 Meter Telescope at Visible Wavelengths

    NASA Astrophysics Data System (ADS)

    Ammons, S. Mark; Johnson, Luke; Laag, Edward A.; Kupke, Renate; Gavel, Donald T.; Bauman, Brian J.; Max, Claire E.

    2010-05-01

    One important frontier for astronomical adaptive optics (AO) involves methods such as multi-object AO and multi-conjugate AO that have the potential to give a significantly larger field of view than conventional AO techniques. A second key emphasis over the next decade will be to push astronomical AO to visible wavelengths. We have conducted the first laboratory simulations of wide-field, laser guide star AO at visible wavelengths on a 10 m class telescope. These experiments, utilizing the UCO/Lick Observatory’s multi-object/laser tomographic adaptive optics (MOAO/LTAO) test bed, demonstrate new techniques in wave front sensing and control that are crucial to future on-sky MOAO systems. We (1) test and confirm the feasibility of highly accurate atmospheric tomography with laser guide stars, (2) demonstrate key innovations allowing open-loop operation of Shack–Hartmann wave front sensors (with errors of ∼30 nm) as will be needed for MOAO, and (3) build a complete error budget model describing system performance. The AO system maintains a performance of 32.4% Strehl ratio on-axis, with 24.5% and 22.6% at 10″ and 15″, respectively, at a science wavelength of 710 nm (R-band) over the equivalent of 0.8 s of simulation. The mean ensquared energy on-axis in a 50 mas spaxel is 46%. The off-axis Strehl ratios are obtained at radial separations 2–3 times the isoplanatic angle of the atmosphere at 710 nm. The MOAO-corrected field of view is ∼25 times larger in area than that limited by anisoplanatism at R-band. The error budget we assemble is composed almost entirely of terms verified through independent, empirical experiments, with minimal parameterization of theoretical models. We find that error terms arising from calibration inaccuracies and optical drift are comparable in magnitude to traditional terms like fitting error and tomographic error. This makes a strong case for implementing additional calibration facilities in future AO systems, including

  9. Heart rate recovery after the 10-m incremental shuttle walking test in older adults with intellectual disabilities.

    PubMed

    Oppewal, Alyt; Hilgenkamp, Thessa I M; van Wijck, Ruud; Evenhuis, Heleen M

    2014-03-01

    Heart rate recovery (HRR) after exercise is an independent predictor for cardiovascular and all-cause mortality. To investigate the usefulness of HRR in cardiorespiratory exercise testing in older adults with intellectual disabilities (ID), the aims of this study were (a) to assess HRR in older adults with ID after the 10-m incremental shuttle walking test (ISWT) and (b) its association with personal characteristics (gender, age, distance walked on the ISWT, level of ID, genetic syndrome causing ID, autism, behavioral problems, and peak heart rate (HRpeak)). HRR was assessed after the 10-m incremental shuttle walking test in 300 older adults (>50 years) with borderline to profound ID. HRR was defined as the change from HRpeak during the ISWT to heart rate measured after 1, 2, 3, 4, and 5 min of passive recovery. The largest decrease in heart rate was in the first minute of recovery leveling off toward the fifth minute of recovery. An abnormal HHR (≤12 bpm) was seen in 36.1% of the participants with Down syndrome (DS) and in 30.7% of the participants with ID by other causes. After the fifth minute the heart rates of 69.4% of the participants with DS and of 61.4% of the participants with ID by other causes returned to resting levels. HRpeak and distance walked on the ISWT were positively related to all HRR measures. More severe ID was negatively related and having DS positively related to HRR after 3-5 min of recovery. The other characteristics were not significantly associated to HRR. HRR is a potentially useful outcome measure in cardiorespiratory fitness testing of older adults with ID with a direct, objective, and non-invasive measurement. Further research is needed to identify the relation between HRR and adverse health outcomes in this population.

  10. The Travelling Telescope

    NASA Astrophysics Data System (ADS)

    Owen, Daniel

    2015-08-01

    The telescope has been around for over 400 years, yet most people have never looked though one. We invite people outside under the stars to learn about those curious lights in the sky, and have a close encounter with the cosmos.Our main aim is to promote science, technology, engineering, and mathematics to the young minds by inspiring, empowering and engaging them using astronomy and astrophysics tools and concepts. We would like to see Africa compete with the rest of the world and we believe this can happen through having a scientifically literate society. We also work closely wit teachers, parents and the general public to further our objectives. We will present on our recently awarded project to work with schools in rural coastal Kenya, a very poor area of the country. We will also present on other work we continue to do with schools to make our project sustainable even after the OAD funding.

  11. Hubble Space Telescope Image

    NASA Technical Reports Server (NTRS)

    1997-01-01

    Astronomers using the Hubble Space Telescope (HST) have identified what may be the most luminous star known; a celestial mammoth that releases up to 10-million times the power of the Sun and is big enough to fill the diameter of Earth's orbit. The star unleashes as much energy in six seconds as our Sun does in one year. The image, taken by a UCLA-led team with the recently installed Near-Infrared Camera and Multi-Object Spectrometer (NICMOS) aboard the HST, also reveals a bright nebula, created by extremely massive stellar eruptions. The UCLA astronomers estimate that the star, called the Pistol Star, (for the pistol shaped nebula surrounding it), is approximately 25,000 light-years from Earth, near the center of our Milky Way galaxy. The Pistol Star is not visible to the eye, but is located in the direction of the constellation Sagittarius, hidden behind the great dust clouds along the Milky Way

  12. Composite telescope technology

    NASA Astrophysics Data System (ADS)

    Chen, Peter C.; Rabin, Douglas

    2014-07-01

    We report the development of optical mirrors based on polymer matrix composite materials. Advantages of this technology are low cost and versatility. By using appropriate combinations of polymers and various metallic and nonmetallic particles and fibers, the properties of the materials can be tailored to suit a wide variety of applications. We report the fabrication and testing of flat and curved mirrors made with metal powders, multiple mirrors replicated with high degree of uniformity from the same mandrels, cryogenic testing, mirrors made of ferromagnetic materials that can be actively or adaptively controlled by non-contact actuation, optics with very smooth surfaces made by replication, and by spincasting. We discuss development of a new generation of ultra-compact, low power active optics and 3D printing of athermal telescopes.

  13. Information and Communications Technology (ICT) Infrastructure for the ASTRI SST-2M telescope prototype for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Gianotti, F.; Tacchini, A.; Leto, G.; Martinetti, E.; Bruno, P.; Bellassai, G.; Conforti, V.; Gallozzi, S.; Mastropietro, M.; Tanci, C.; Malaguti, G.; Trifoglio, M.

    2016-08-01

    The Cherenkov Telescope Array (CTA) represents the next generation of ground-based observatories for very high energy gamma-ray astronomy. The CTA will consist of two arrays at two different sites, one in the northern and one in the southern hemisphere. The current CTA design foresees, in the southern site, the installation of many tens of imaging atmospheric Cherenkov telescopes of three different classes, namely large, medium and small, so defined in relation to their mirror area; the northern hemisphere array would consist of few tens of the two larger telescope types. The Italian National Institute for Astrophysics (INAF) is developing the Cherenkov Small Size Telescope ASTRI SST- 2M end-to-end prototype telescope within the framework of the International Cherenkov Telescope Array (CTA) project. The ASTRI prototype has been installed at the INAF observing station located in Serra La Nave on Mt. Etna, Italy. Furthermore a mini-array, composed of nine of ASTRI telescopes, has been proposed to be installed at the Southern CTA site. Among the several different infrastructures belonging the ASTRI project, the Information and Communication Technology (ICT) equipment is dedicated to operations of computing and data storage, as well as the control of the entire telescope, and it is designed to achieve the maximum efficiency for all performance requirements. Thus a complete and stand-alone computer centre has been designed and implemented. The goal is to obtain optimal ICT equipment, with an adequate level of redundancy, that might be scaled up for the ASTRI mini-array, taking into account the necessary control, monitor and alarm system requirements. In this contribution we present the ICT equipment currently installed at the Serra La Nave observing station where the ASTRI SST-2M prototype will be operated. The computer centre and the control room are described with particular emphasis on the Local Area Network scheme, the computing and data storage system, and the

  14. The Metagenomic Telescope

    PubMed Central

    Szalkai, Balázs; Scheer, Ildikó; Nagy, Kinga; Vértessy, Beáta G.; Grolmusz, Vince

    2014-01-01

    Next generation sequencing technologies led to the discovery of numerous new microbe species in diverse environmental samples. Some of the new species contain genes never encountered before. Some of these genes encode proteins with novel functions, and some of these genes encode proteins that perform some well-known function in a novel way. A tool, named the Metagenomic Telescope, is described here that applies artificial intelligence methods, and seems to be capable of identifying new protein functions even in the well-studied model organisms. As a proof-of-principle demonstration of the Metagenomic Telescope, we considered DNA repair enzymes in the present work. First we identified proteins in DNA repair in well–known organisms (i.e., proteins in base excision repair, nucleotide excision repair, mismatch repair and DNA break repair); next we applied multiple alignments and then built hidden Markov profiles for each protein separately, across well–researched organisms; next, using public depositories of metagenomes, originating from extreme environments, we identified DNA repair genes in the samples. While the phylogenetic classification of the metagenomic samples are not typically available, we hypothesized that some very special DNA repair strategies need to be applied in bacteria and Archaea living in those extreme circumstances. It is a difficult task to evaluate the results obtained from mostly unknown species; therefore we applied again the hidden Markov profiling: for the identified DNA repair genes in the extreme metagenomes, we prepared new hidden Markov profiles (for each genes separately, subsequent to a cluster analysis); and we searched for similarities to those profiles in model organisms. We have found well known DNA repair proteins, numerous proteins with unknown functions, and also proteins with known, but different functions in the model organisms. PMID:25054802

  15. The metagenomic telescope.

    PubMed

    Szalkai, Balázs; Scheer, Ildikó; Nagy, Kinga; Vértessy, Beáta G; Grolmusz, Vince

    2014-01-01

    Next generation sequencing technologies led to the discovery of numerous new microbe species in diverse environmental samples. Some of the new species contain genes never encountered before. Some of these genes encode proteins with novel functions, and some of these genes encode proteins that perform some well-known function in a novel way. A tool, named the Metagenomic Telescope, is described here that applies artificial intelligence methods, and seems to be capable of identifying new protein functions even in the well-studied model organisms. As a proof-of-principle demonstration of the Metagenomic Telescope, we considered DNA repair enzymes in the present work. First we identified proteins in DNA repair in well-known organisms (i.e., proteins in base excision repair, nucleotide excision repair, mismatch repair and DNA break repair); next we applied multiple alignments and then built hidden Markov profiles for each protein separately, across well-researched organisms; next, using public depositories of metagenomes, originating from extreme environments, we identified DNA repair genes in the samples. While the phylogenetic classification of the metagenomic samples are not typically available, we hypothesized that some very special DNA repair strategies need to be applied in bacteria and Archaea living in those extreme circumstances. It is a difficult task to evaluate the results obtained from mostly unknown species; therefore we applied again the hidden Markov profiling: for the identified DNA repair genes in the extreme metagenomes, we prepared new hidden Markov profiles (for each genes separately, subsequent to a cluster analysis); and we searched for similarities to those profiles in model organisms. We have found well known DNA repair proteins, numerous proteins with unknown functions, and also proteins with known, but different functions in the model organisms.

  16. Smart co-phasing system for segmented mirror telescopes

    NASA Astrophysics Data System (ADS)

    Simar, Juan F.; Stockman, Yvan; Surdej, Jean

    2016-07-01

    Space observations of fainter and more distant astronomical objects constantly require telescope primary mirrors with a larger size. The diameter of monolithic primary mirrors is limited to 10 m because of manufacturing and logistics limitations. For space telescopes, monolithic primary mirrors are limited to less than 5 m due to fairing capacity. Segmented primary mirrors thus constitute an alternative solution to deal with the steadily increase of the primary mirror size. The optical path difference between the individual segments must be close to zero (few nm) in order to be diffraction limited over the full telescope aperture. In this paper a new system that may co-phase 7 segments at once with the light of a star and without artificial one is proposed. First the measuring methods and feedback system is explained, then the breadboard setup is presented and the results are analyzed and discussed, finally a comparison with Keck telescope is performed. This system can be adapted in order to be used in the co-phasing system of future segmented mirrors, its dynamic range starts from several hundred of microns till some tenths of nanometers

  17. The Zadko Telescope: Exploring the Transient Universe

    NASA Astrophysics Data System (ADS)

    Coward, D. M.; Gendre, B.; Tanga, P.; Turpin, D.; Zadko, J.; Dodson, R.; Devogéle, M.; Howell, E. J.; Kennewell, J. A.; Boër, M.; Klotz, A.; Dornic, D.; Moore, J. A.; Heary, A.

    2017-01-01

    The Zadko telescope is a 1 m f/4 Cassegrain telescope, situated in the state of Western Australia about 80-km north of Perth. The facility plays a niche role in Australian astronomy, as it is the only meter class facility in Australia dedicated to automated follow-up imaging of alerts or triggers received from different external instruments/detectors spanning the entire electromagnetic spectrum. Furthermore, the location of the facility at a longitude not covered by other meter class facilities provides an important resource for time critical projects. This paper reviews the status of the Zadko facility and science projects since it began robotic operations in March 2010. We report on major upgrades to the infrastructure and equipment (2012-2014) that has resulted in significantly improved robotic operations. Second, we review the core science projects, which include automated rapid follow-up of gamma ray burst (GRB) optical afterglows, imaging of neutrino counterpart candidates from the ANTARES neutrino observatory, photometry of rare (Barbarian) asteroids, supernovae searches in nearby galaxies. Finally, we discuss participation in newly commencing international projects, including the optical follow-up of gravitational wave (GW) candidates from the United States and European GW observatory network and present first tests for very low latency follow-up of fast radio bursts. In the context of these projects, we outline plans for a future upgrade that will optimise the facility for alert triggered imaging from the radio, optical, high-energy, neutrino, and GW bands.

  18. A project of a two meter telescope in North Africa

    NASA Astrophysics Data System (ADS)

    Benkhaldoun, Zouhair

    2015-03-01

    Site testing undertaken during the last 20 years by Moroccan researchers through international studies have shown that the Atlas mountains in Morocco has potentialities similar to those sites which host the largest telescopes in world. Given the quality of the sites and opportunities to conduct modern research, we believe that the installation of a 2m diameter telescope will open new horizons for Astronomy in Morocco and north Africa allowing our region to enter definitively into the very exclusive club of countries possessing an instrument of that size. A state of the art astrophysical observatory on any good astronomical observation site should be equipped with a modern 2m-class, robotic telescope and some smaller telescopes. Our plan should be to operate one of the most efficient robotic 2m class telescopes worldwide in order to offer optimal scientific opportunities for researchers and maintain highest standards for the education of students. Beside all categories of astronomical research fields, students will have the possibility to be educated intensively on the design, manufacturing and operating of modern state of the art computer controlled instruments. In the frame of such education and observation studies several PhD and dissertational work packages are possible. Many of the observations will be published in articles worldwide and a number of guest observers from other countries will have the possibility to take part in collaborations. This could be a starting point of an international reputation of our region in the field of modern astronomy.

  19. A Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST)

    NASA Astrophysics Data System (ADS)

    Conti, Alberto; Arenberg, Jonathan; Baldauf, Brian

    2017-01-01

    The “Search for Life” (direct imaging of earth-like planets) will require extremely stable telescopes with apertures in the 10 m to 20 m range. Such apertures are larger than what can be delivered to space using current or planned future launch vehicles. Building and assembling large telescopes in space is therefore likely to require not only multiple launches but importantly assembly in spce. As a result, space-based telescopes with large apertures will require major changes to our conventional telescope design and architecture.Here we report on the concept for the Modular Orbital Demonstration of an Evolvable Space Telescope (MODEST) to demonstrates the on-orbit robotic and/or astronaut assembly of an optical telescope in space. MODEST is a proposed International Space Station (ISS demonstration that will make use of the standard Express Logistics Carriers (ELCs) and can mounted to one of a variety of ISS pallets.MODEST will provides significant risk reduction for the next generation of space observatories, and demonstrates the technology needed to assemble a six-mirror phased telescope. Key modest features include the use of an active primary optical surface with wavefront feedback control to allow on-orbit optimization, and the precise surface control to meet optical system wavefront and stability requirements.MODEST will also be used to evaluate advances in lightweight mirror and metering structure materials such as SiC or Carbon Fiber Reinforced Polymer (CFRP) that have excellent mechanical and thermal properties, e.g. high stiffness, high modulus, high thermal conductivity, and low thermal expansion. Mirrors built from these materials can be rapidly replicated in a highly cost effective manner, making them an excellent candidate for a low cost, high performance Optical Telescope Assembly paving the way for enabling affordable solutions for the next generation of large aperture space-based telescope.MODEST post-assembly value includes space, ground, and

  20. Kashima 34-m Radio Telescope

    NASA Technical Reports Server (NTRS)

    Sekido, Mamoru; Kawai, Eiji

    2013-01-01

    The Kashima 34-m radio telescope has been continuously operated and maintained by the National Institute of Information and Communications Technology (NICT) as a facility of the Kashima Space Technology Center (KSTC) in Japan. This brief report summarizes the status of this telescope, the staff, and activities during 2012.

  1. Astrometry with Hubble Space Telescope

    NASA Astrophysics Data System (ADS)

    Benedict, G.; Murdin, P.

    2000-11-01

    In 1990 NASA launched the HUBBLE SPACE TELESCOPE. In addition to cameras and spectrographs usable from the far ultraviolet to the near-infrared, the observatory contains three white-light INTERFEROMETERS. As part of engineering and science support their primary task was telescope guiding; to position and hold science targets within the science instrument apertures with tolerances approaching 0.1'...

  2. Telescopes, Mounts and Control Systems

    NASA Astrophysics Data System (ADS)

    Mobberley, M.; Murdin, P.

    2003-04-01

    The amateur astronomer used to have a relatively basic choice of equipment: a refractor (see REFRACTING TELESCOPES), or a Newtonian reflector (see REFLECTING TELESCOPES); there were few other options. The refractor has always been the stereotype astronomer's instrument: a spy glass, with a lens at one end and an eyepiece at the other. However, in practice, the reflector has always been better aper...

  3. Asteroseismology with FRESIP: A meter class space telescope

    NASA Technical Reports Server (NTRS)

    Milford, Peter

    1994-01-01

    The requirements for asteroseismology and searching for occulting inner planets are similar. The FRESIP mission will be suited to making asteroseismology measurements. Recommendation: Use 30-60 second integrations from one or more CCD's in the FRESIP mosaic, sampled continuously for the entire mission to measure stellar non-radial oscillations with amplitudes of parts per million and frequencies of 0.1 to 10 MHz. These measurements lead to determination of stellar interior helium abundances, rotation rates, depth of convection zones and measuring stellar cycle frequency changes for a variety of stellar types, enabling major advances in stellar structure and evolutionary theories.

  4. Wind buffeting of large telescopes.

    PubMed

    MacMynowski, Douglas G; Andersen, Torben

    2010-02-01

    Unsteady wind loads due to turbulence within the telescope enclosure are one of the largest dynamic disturbances for ground-based optical telescopes. The desire to minimize the response to the wind influences the design of the telescope enclosure, structure, and control systems. There is now significant experience in detailed integrated modeling to predict image jitter due to wind. Based on this experience, a relatively simple model is proposed that is verified (from a more detailed model) to capture the relevant physics. In addition to illustrating the important elements of the telescope design that influence wind response, this model is used to understand the sensitivity of telescope image jitter to a wide range of design parameters.

  5. A suggested 12-m telescope optical system configuration for China

    NASA Astrophysics Data System (ADS)

    Su, Ding-qiang; Liang, Ming; Yuan, Xiangyan; Bai, Hua; Cui, Xiangqun

    2016-08-01

    This is an optical/infrared telescope. It is a general purpose telescope. A segmented primary mirror is adopted with diameter 12 m and f-ratio 1.6. This telescope has prime focus, Cassegrain, Nasmyth and coudé systems. The prime focus system has a 1.5° field-of-view corrector with excellent image quality. It will be used for multi-object fibre spectroscopic observation and CCD photography. In this 12-m telescope, all systems except the prime focus system share the same secondary mirror; the Nasmyth and coudé systems are formed by adding relay mirrors; and the method of moving a secondary mirror is used to enhance image quality. All these features originate from the innovative optical system of the Chinese 2.16-m telescope. At the Cassegrain focus, a dark object spectrograph, for example, can be installed without any corrector; and in case a field of view is needed, a corrector may be added. Both the Nasmyth and coudé systems have exceptionally excellent image quality and the exchange between them occurs very conveniently. Many instruments in visible and infrared wavebands, some with an adaptive optics system, will be installed at the Nasmyth platform. Coudé system will be used for interferometry and for those instruments which require high stability. This configuration has a nearly full range of systems but it is not complex, and it can even be adopted by 20-40-m class telescopes.

  6. Monitoring Io volcanism with AO telescopes during and after the NH flyby

    NASA Astrophysics Data System (ADS)

    Marchis, F.; Spencer, J. R.; Lopes, R. M.; Davies, A. G.; Dumas, C.

    2007-12-01

    To support the New Horizons (NH) Jupiter encounter we monitored Io's volcanic activity using high angular resolution images in the near infrared (1-5 microns) provided by adaptive optics (AO) systems available on 8-10m class telescopes. We initiated the campaign on Feb. 25 2007 with data obtained with the VLT-Yepun telescope (ESO, Paranal, Chile), just before NH closest approach. We continued monitoring with the Gemini North telescope (Hawaii, USA). The last observation was taken on May 28 2007. Numerous active volcanoes are visible in the data but the Tvashtar eruption is by far the most energetic. Extremely high angular resolution data from NH revealed fine detail of the eruption, such as the presence of an active plume [1]. This volcano has an interesting past history. It was seen as a powerful eruption from Nov. 26 1999 during the Galileo I25 [2] flyby to Feb. 19 2001 from the ground [3]. It was dormant or below our ground-based limit of detection (T<330 K assuming an area of 460 km2) between Dec 2001 and May 2004 [4,5]. The re-awakening of the volcano was reported by Laver et al. [6] in April 2006 based on Keck Adaptive Optics (AO) observations. Our last Gemini AO observation taken on May 26 shows that Tvashtar was still very active. Based on the previous behavior of this volcano [7] it is very likely that the activity reported in 2007 is a continuation of the Tvashtar-2006 eruption. Other hot spots, such as Loki Patera, Pele, and a new hot spot located north of Loki Patera, were seen in our data. We will describe the global picture of Io's volcanic activity derived from our observations, comparing it with previous observations from the Galileo spacecraft and using ground-based AO. 1. Spencer et al., AGU, this session, 2007 2. McEwen et al., Science, 288, 1193-1198, 2000 3. Marchis et al. Icarus, 160, 124-131, 2002 4. Marchis et al., Icarus, 176, 1, 2005 5. Marchis et al., AGU Fall meeting, V33C-1483, 2004 6. Laver et al., Icarus, in press, 2006 7. Milazzo et

  7. The ASTRI prototype and mini-array: precursor telescopes for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Pareschi, Giovanni

    2016-07-01

    In the framework of the Cherenkov Telescope Array (CTA) Observatory, the Italian National Institute of Astrophysics (INAF) has recently inaugurated in Sicily (Italy), at the Serra La Nave astronomical site on the slopes of Mount Etna, a large field of view (9.6 degrees) dual-mirror prototype (ASTRI SST-2M) of the CTA small size class of telescopes. CTA plans to install about 70 small size telescopes in the southern site to allow the study of the gamma rays from a few TeV up to hundreds of TeV. The ASTRI SST-2M telescope prototype has been developed following an end-to-end approach, since it includes the entire system of structure, mirror's optics (primary and secondary mirrors), camera, and control/acquisition software. Although it is a technological prototype, the ASTRI SST-2M prototype will be able to perform systematic monitoring of bright TeV sources. A remarkable improvement in terms of performance could come from the operation of the ASTRI mini-array, led by INAF in synergy with the Universidade de Sao Paulo (Brazil) and the North-West University (South Africa) and with also a contribution by INFN. The ASTRI mini-array will be composed of at least nine ASTRI SST-2M units. It is proposed as one of the CTA mini-array of telescope precursors and initial seeds of CTA, to be installed at the final CTA southern site. Apart from the assessment of a number of technological aspects related to CTA, the ASTRI mini-array will extend and improve the sensitivity, similar to the H.E.S.S. one in the 1-10 TeV energy range, up to about 100 TeV.

  8. Class Matters

    ERIC Educational Resources Information Center

    Valdata, Patricia

    2005-01-01

    Ever since George Washington opted for the title of president rather than king, Americans have been uncomfortable with the idea of class distinctions. This article presents an interview with Dr. Janet Galligani Casey regarding the idea of class distinctions. Galligani Casey, who grew up in a working-class neighborhood in Somerville, Massachusetts,…

  9. Class Size.

    ERIC Educational Resources Information Center

    Underwood, Siobhan; Lumsden, Linda S.

    1994-01-01

    The items featured in this annotated bibliography touch on several aspects of the multifaceted class-size debate. Allen Odden reviews the literature and contends that class-size reduction should be used "sparingly and strategically." C. M. Achilles and colleagues examines two different class-size situations and find student test…

  10. DAG Telescope: A New Potential for MOS Observations

    NASA Astrophysics Data System (ADS)

    Alis, S.; Yesilyaprak, C.; Yerli, S. K.

    2016-10-01

    East Anatolian Observatory (aka. DAG) is a national project supported by the Turkish Government for building a 4 m class telescope which will be working in the optical and near-IR domain. As the tender process has been completed and kick-off to the telescope and the mirror production has been initiated, the project team is looking for possible collaborations for the focal plane instrumentation. This contribution is intended to describe the DAG project and to show its opportunities for a state-of-the-art MOS instrument.

  11. Holographically corrected telescope for high-bandwidth optical communications.

    PubMed

    Andersen, G; Knize, R J

    1999-11-20

    We present a design for an optical data communications receiver-transmitter pair based on the holographic correction of a large diameter, poor-quality, reflecting primary mirror. The telescope has a narrow bandwidth (<0.1 nm) with good signal frequency isolation (>60 dB) and is scalable to meter-class apertures. We demonstrate the correction of a reflector telescope with over 2000 waves of aberration to diffraction-limited operation, capable of handling data transmission rates up to 100 GHz.

  12. Control Software for the VERITAS Cerenkov Telescope System

    NASA Astrophysics Data System (ADS)

    Krawczynski, H.; Olevitch, M.; Sembroski, G.; Gibbs, K.

    2003-07-01

    The VERITAS collab oration is developing a system of initially 4 and ˇ eventually 7 Cerenkov telescopes of the 12 m diameter class for high sensitivity gamma-ray astronomy in the >50 GeV energy range. In this contribution we describe the software that controls and monitors the various VERITAS subsystems. The software uses an object-oriented approach to cop e with the complexities that arise from using sub-groups of the 7 VERITAS telescopes to observe several sources at the same time. Inter-pro cess communication is based on the CORBA object Request Broker proto col and watch-dog processes monitor the sub-system performance.

  13. Seismic Imager Space Telescope

    NASA Technical Reports Server (NTRS)

    Sidick, Erkin; Coste, Keith; Cunningham, J.; Sievers,Michael W.; Agnes, Gregory S.; Polanco, Otto R.; Green, Joseph J.; Cameron, Bruce A.; Redding, David C.; Avouac, Jean Philippe; Ampuero, Jean Paul; Leprince, Sebastien; Michel, Remi

    2012-01-01

    A concept has been developed for a geostationary seismic imager (GSI), a space telescope in geostationary orbit above the Pacific coast of the Americas that would provide movies of many large earthquakes occurring in the area from Southern Chile to Southern Alaska. The GSI movies would cover a field of view as long as 300 km, at a spatial resolution of 3 to 15 m and a temporal resolution of 1 to 2 Hz, which is sufficient for accurate measurement of surface displacements and photometric changes induced by seismic waves. Computer processing of the movie images would exploit these dynamic changes to accurately measure the rapidly evolving surface waves and surface ruptures as they happen. These measurements would provide key information to advance the understanding of the mechanisms governing earthquake ruptures, and the propagation and arrest of damaging seismic waves. GSI operational strategy is to react to earthquakes detected by ground seismometers, slewing the satellite to point at the epicenters of earthquakes above a certain magnitude. Some of these earthquakes will be foreshocks of larger earthquakes; these will be observed, as the spacecraft would have been pointed in the right direction. This strategy was tested against the historical record for the Pacific coast of the Americas, from 1973 until the present. Based on the seismicity recorded during this time period, a GSI mission with a lifetime of 10 years could have been in position to observe at least 13 (22 on average) earthquakes of magnitude larger than 6, and at least one (2 on average) earthquake of magnitude larger than 7. A GSI would provide data unprecedented in its extent and temporal and spatial resolution. It would provide this data for some of the world's most seismically active regions, and do so better and at a lower cost than could be done with ground-based instrumentation. A GSI would revolutionize the understanding of earthquake dynamics, perhaps leading ultimately to effective warning

  14. Pre-selecting muon events in the camera server of the ASTRI telescopes for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Maccarone, Maria C.; Mineo, Teresa; Capalbi, Milvia; Conforti, Vito; Coffaro, Martina

    2016-08-01

    The Cherenkov Telescope Array (CTA) represents the next generation of ground based observatories for very high energy gamma ray astronomy. The CTA will consist of two arrays at two different sites, one in the northern and one in the southern hemisphere. The current CTA design foresees, in the southern site, the installation of many tens of imaging atmospheric Cherenkov telescopes of three different classes, namely large, medium, and small, so defined in relation to their mirror area; the northern hemisphere array would consist of few tens of the two larger telescope types. The telescopes will be equipped with cameras composed either of photomultipliers or silicon photomultipliers, and with different trigger and read-out electronics. In such a scenario, several different methods will be used for the telescopes' calibration. Nevertheless, the optical throughput of any CTA telescope, independently of its type, can be calibrated analyzing the characteristic image produced by local atmospheric highly energetic muons that induce the emission of Cherenkov light which is imaged as a ring onto the focal plane if their impact point is relatively close to the telescope optical axis. Large sized telescopes would be able to detect useful muon events under stereo coincidence and such stereo muon events will be directly addressed to the central CTA array data acquisition pipeline to be analyzed. For the medium and small sized telescopes, due to their smaller mirror area and large inter-telescope distance, the stereo coincidence rate will tend to zero; nevertheless, muon events will be detected by single telescopes that must therefore be able to identify them as possible useful calibration candidates, even if no stereo coincidence is available. This is the case for the ASTRI telescopes, proposed as pre-production units of the small size array of the CTA, which are able to detect muon events during regular data taking without requiring any dedicated trigger. We present two fast

  15. A Ten-Meter Ground-Station Telescope for Deep-Space Optical Communications: A Preliminary Design

    NASA Technical Reports Server (NTRS)

    Britcliffe, M.; Hoppe, D.; Roberts, W.; Page, N.

    2001-01-01

    This article describes a telescope design for a 10-m optical ground station for deep-space communications. The design for a direct-detection optical communications telescope differs dramatically from a telescope for imaging applications. In general, the requirements for optical manufacturing and tracking performance are much less stringent for direct detection of optical signals. The technical challenge is providing a design that will operate in the daytime/nighttime conditions required for a Deep Space Network tracking application. The design presented addresses these requirements. The design will provide higher performance at lower cost than existing designs.

  16. MeV electron acceleration at 1kHz with <10 mJ laser pulses

    NASA Astrophysics Data System (ADS)

    Salehi, Fatholah; Goers, Andy; Hine, George; Feder, Linus; Kuk, Donghoon; Kim, Ki-Yong; Milchberg, Howard

    2016-10-01

    We demonstrate laser driven acceleration of electrons at 1 kHz repetition rate with pC charge above 1MeV per shot using < 10 mJ pulse energies focused on a near-critical density He or H2 gas jet. Using the H2 gas jet, electron acceleration to 0.5 MeV in 10 fC bunches was observed with laser pulse energy as low as 1.3mJ . Using a near-critical density gas jet sets the critical power required for relativistic self-focusing low enough for mJ scale laser pulses to self- focus and drive strong wakefields. Experiments and particle-in-cell simulations show that optimal drive pulse duration and chirp for maximum electron bunch charge and energy depends on the target gas species. High repetition rate, high charge, and short duration electron bunches driven by very modest pulse energies constitutes an ideal portable electron source for applications such as ultrafast electron diffraction experiments and high rep. rate γ-ray production. This work is supported by the US Department of Energy, the National Science Foundation, and the Air Force Office of Scientific Research.

  17. A 10 mK scanning tunneling microscope operating in ultra high vacuum and high magnetic fields.

    PubMed

    Assig, Maximilian; Etzkorn, Markus; Enders, Axel; Stiepany, Wolfgang; Ast, Christian R; Kern, Klaus

    2013-03-01

    We present design and performance of a scanning tunneling microscope (STM) that operates at temperatures down to 10 mK providing ultimate energy resolution on the atomic scale. The STM is attached to a dilution refrigerator with direct access to an ultra high vacuum chamber allowing in situ sample preparation. High magnetic fields of up to 14 T perpendicular and up to 0.5 T parallel to the sample surface can be applied. Temperature sensors mounted directly at the tip and sample position verified the base temperature within a small error margin. Using a superconducting Al tip and a metallic Cu(111) sample, we determined an effective temperature of 38 ± 1 mK from the thermal broadening observed in the tunneling spectra. This results in an upper limit for the energy resolution of ΔE = 3.5 kBT = 11.4 ± 0.3 μeV. The stability between tip and sample is 4 pm at a temperature of 15 mK as demonstrated by topography measurements on a Cu(111) surface.

  18. High-cycle fatigue of 10M Ni-Mn-Ga magnetic shape memory alloy in reversed mechanical loading

    NASA Astrophysics Data System (ADS)

    Aaltio, I.; Soroka, A.; Ge, Y.; Söderberg, O.; Hannula, S.-P.

    2010-07-01

    Application of Ni-Mn-Ga magnetic shape memory alloys in magnetic-field-induced actuation relies on their performance in long-term high-cycle fatigue. In this paper the performance and changes in the microstructure of a Ni-Mn-Ga 10M martensite single crystal material are reported in a long-term mechanically induced shape change cycling. The longest test was run for 2 × 109 cycles at a frequency of 250 Hz and a strain amplitude of ± 1%. After the test a clear increase of the dynamic stiffness of the material was detected. Three specimens out of ten were cycled until fracture occurred and their fracture mechanism was studied. It was observed that the macroscopic crack growth took place roughly at a 45° angle with respect to the loading direction that was along the lang100rang crystallographic direction of the sample. The macroscopic fracture plane seemed to correspond roughly to the {111} crystal planes. On a microscopic scale the fracture propagated in a step-like manner at least partly along crystallographic planes. The steps at the fracture plane correspond to the {101} twin planes, with the height of steps along the lang101rang direction. The final fracture of the samples occurred in a brittle manner after the critical stress was exceeded.

  19. SOFIA: Flying the Telescope

    NASA Technical Reports Server (NTRS)

    Asher, Troy; Cumming, Steve

    2012-01-01

    The Stratospheric Observatory For Infrared Astronomy (SOFIA) is an international cooperative development and operations program between the United States National Aeronautics and Space Administration (NASA) and the German Space Agency, DLR (Deutsches Zentrum fuer Luft-und Raumfahrt). SOFIA is a 2.5 meter, optical/infrared/sub-millimeter telescope mounted in a Boeing model 747SP-21 aircraft and will be used for many basic astronomical observations performed at stratospheric altitudes. It will accommodate installation of different focal plane instruments with in-flight accessibility provided by investigators selected from the international science community. The Facility operational lifetime is planned to be greater than 20 years. This presentation will present the results of developmental testing of SOFIA, including analysis, envelope expansion and the first operational mission. It will describe a brief history of open cavities in flight, how NASA designed and tested SOFIAs cavity, as well as flight test results. It will focus on how the test team achieved key milestones by systematically and efficiently reducing the number of test points to only those absolutely necessary to achieve mission requirements, thereby meeting all requirements and saving the potential loss of program funding. Finally, it will showcase examples of the observatory in action and the first operational mission of the observatory, illustrating the usefulness of the system to the international scientific community. Lessons learned on how to whittle a mountain of test points into a manageable sum will be presented at the conclusion.

  20. Astronomy with Small Telescopes

    NASA Astrophysics Data System (ADS)

    Paczynski, Bohdan

    2006-06-01

    While there are more than a dozen telescopes larger than 10 meters there is plenty of interesting astronomy which can be done with much smaller instruments. Notice that the existing SDSS, and the future PanSTARRS and LSST saturate at 15 mag. An example of interesting science is provided with ASAS (All Sky Automated Survey) which used aperture of 7 cm to discover over 50,000 variable stars brighter than 14 mag, covering almost 3/4 of the sky. Most of these are new discoveries.ASAS like instruments are most likely more efficient in a search for afterglows following gamma-ray bursts (GRB) than CFHT and its Megacam. In fact it should be possible to detect the afterglows without a GRB trigger by imaging all visible sky every 15 minutes down to 16 mag using a number of ASAS-like instruments.Another example of small instruments being essential, is their ability to detect 'killer asteroids' prior to their impact. It will take a number of small instruments, somewhat more powerful than ASAS, to detect boulders as small as 10 - 20 meters at a distance of several days prior to their impact. This will provide time to evacuate a region in case of Tunguska-like event, or to provide news of a spectacular but harmless event in case of a more modest impact.

  1. POST: Polar Stratospheric Telescope

    NASA Astrophysics Data System (ADS)

    Bely, Pierre Y.; Ford, Holland C.; Burg, Richard; Petro, Larry; White, Rick; Bally, John

    1995-10-01

    The tropopause, typically at 16 to 18 km altitude at the lower latitudes, dips to 8 km in the polar regions. This makes the cold, dry and nonturbulent lower stratosphere accessible to tethered aerostats. Tethered aerostats can fly as high as 12 km and are extremely reliable, lasting for many years. In contrast to free-flying balloons, they can stay on station for weeks at a time, and payloads can be safely recovered for maintenance and adjustment and relaunched in a matter of hours. We propose to use such a platform, located first in the Arctic (near Fairbanks, Alaska) and, potentially, later in the Antarctic, to operate a new technology 6-meter, diluted aperture telescope with diffraction-limited performance in the near infrared. Thanks to the low ambient temperature (220 K), thermal emission from the optics is of the same order as that of the zodiacal light in the 2 to 3 micron band. Since this wavelength interval is the darkest part of the zodiacal light spectrum from optical wavelengths to 100 microns, the combination of high resolution images and a very dark sky make it the spectral region of choice for observing the redshifted light from galaxies and clusters of galaxies at moderate to high redshifts.

  2. Operating a heterogeneous telescope network

    NASA Astrophysics Data System (ADS)

    Allan, Alasdair; Bischoff, Karsten; Burgdorf, Martin; Cavanagh, Brad; Christian, Damien; Clay, Neil; Dickens, Rob; Economou, Frossie; Fadavi, Mehri; Frazer, Stephen; Granzer, Thomas; Grosvenor, Sandy; Hessman, Frederic V.; Jenness, Tim; Koratkar, Anuradha; Lehner, Matthew; Mottram, Chris; Naylor, Tim; Saunders, Eric S.; Solomos, Nikolaos; Steele, Iain A.; Tuparev, Georg; Vestrand, W. Thomas; White, Robert R.; Yost, Sarah

    2006-06-01

    In the last few years the ubiquitous availability of high bandwidth networks has changed the way both robotic and non-robotic telescopes operate, with single isolated telescopes being integrated into expanding "smart" telescope networks that can span continents and respond to transient events in seconds. The Heterogeneous Telescope Networks (HTN)* Consortium represents a number of major research groups in the field of robotic telescopes, and together we are proposing a standards based approach to providing interoperability between the existing proprietary telescope networks. We further propose standards for interoperability, and integration with, the emerging Virtual Observatory. We present the results of the first interoperability meeting held last year and discuss the protocol and transport standards agreed at the meeting, which deals with the complex issue of how to optimally schedule observations on geographically distributed resources. We discuss a free market approach to this scheduling problem, which must initially be based on ad-hoc agreements between the participants in the network, but which may eventually expand into a electronic market for the exchange of telescope time.

  3. Space Telescope Systems Description Handbook

    NASA Technical Reports Server (NTRS)

    Carter, R. E.

    1985-01-01

    The objective of the Space Telescope Project is to orbit a high quality optical 2.4-meter telescope system by the Space Shuttle for use by the astronomical community in conjunction with NASA. The scientific objectives of the Space Telescope are to determine the constitution, physical characteristics, and dynamics of celestial bodies; the nature of processes which occur in the extreme physical conditions existing in stellar objects; the history and evolution of the universe; and whether the laws of nature are universal in the space-time continuum. Like ground-based telescopes, the Space Telescope was designed as a general-purpose instrument, capable of utilizing a wide variety of scientific instruments at its focal plane. This multi-purpose characteristic will allow the Space Telescope to be effectively used as a national facility, capable of supporting the astronomical needs for an international user community and hence making contributions to man's needs. By using the Space Shuttle to provide scientific instrument upgrading and subsystems maintenance, the useful and effective operational lifetime of the Space Telescope will be extended to a decade or more.

  4. Geodetic Observatory Wettzell - 20-m Radio Telescope and Twin Telescope

    NASA Technical Reports Server (NTRS)

    Neidhardt, Alexander; Kronschnabl, Gerhard; Schatz, Raimund

    2013-01-01

    In the year 2012, the 20-m radio telescope at the Geodetic Observatory Wettzell, Germany again contributed very successfully to the International VLBI Service for Geodesy and Astrometry observing program. Technical changes, developments, improvements, and upgrades were made to increase the reliability of the entire VLBI observing system. In parallel, the new Twin radio telescope Wettzell (TTW) got the first feedhorn, while the construction of the HF-receiving and the controlling system was continued.

  5. Asteroid Detection with the Space Surveillance Telescope

    NASA Astrophysics Data System (ADS)

    Woods, D.; Shah, R.; Johnson, J.; Pearce, E.; Lambour, R.; Faccenda, W.

    2013-09-01

    The Space Surveillance Telescope (SST) is a 3.5 m wide field-of-view system developed for DARPA by MIT Lincoln Laboratory to advance the nation's capabilities in space situational awareness. In addition to the national interest in identifying and cataloging man-made space objects, there is a growing concern for near-Earth asteroid identification and tracking. MIT is developing a program to detect near-Earth asteroids, as an extension of the Lincoln Near-Earth Asteroid Research (LINEAR) survey, to identify potentially hazardous near-Earth objects, and to extend the catalog of known asteroids to smaller sizes (< 140 m). MIT believes SST's capability to detect asteroids on size scales as small as 5-10 m is well suited to provide NASA with a sample of small asteroids of interest for its proposed mission to send astronauts to near-Earth asteroids as a stepping-stone to further manned exploration of the Solar System. The Keck Institute for Space Studies (Brophy et al. 2012), studied the feasibility of asteroid capture into lunar orbit as a destination for additional investigation. A major requirement of such an effort is the development of a sample of suitable asteroids, a job that SST is uniquely able to achieve by means of its capacity for search rate and sensitivity. The SST also brings the capability of high speed photometry at rates of 100 Hz to 1 kHz; we present initial observations of asteroids using the photometers.

  6. B cells expressing IL-10 mRNA modulate memory T cells after DNA-Hsp65 immunization

    PubMed Central

    Fontoura, I. C.; Trombone, A.P.F.; Almeida, L. P.; Lorenzi, J. C. C.; Rossetti, R. A. M.; Malardo, T.; Padilha, E.; Schluchting, W.; Silva, R. L. L.; Gembre, A. F.; Fiuza, J. E. C.; Silva, C. L.; Panunto-Castelo, A.; Coelho-Castelo, A. A. M.

    2015-01-01

    In DNA vaccines, the gene of interest is cloned into a bacterial plasmid that is engineered to induce protein production for long periods in eukaryotic cells. Previous research has shown that the intramuscular immunization of BALB/c mice with a naked plasmid DNA fragment encoding the Mycobacterium leprae 65-kDa heat-shock protein (pcDNA3-Hsp65) induces protection against M. tuberculosis challenge. A key stage in the protective immune response after immunization is the generation of memory T cells. Previously, we have shown that B cells capture plasmid DNA-Hsp65 and thereby modulate the formation of CD8+ memory T cells after M. tuberculosis challenge in mice. Therefore, clarifying how B cells act as part of the protective immune response after DNA immunization is important for the development of more-effective vaccines. The aim of this study was to investigate the mechanisms by which B cells modulate memory T cells after DNA-Hsp65 immunization. C57BL/6 and BKO mice were injected three times, at 15-day intervals, with 100 µg naked pcDNA-Hsp65 per mouse. Thirty days after immunization, the percentages of effector memory T (TEM) cells (CD4+ and CD8+/CD44high/CD62Llow) and memory CD8+ T cells (CD8+/CD44high/CD62Llow/CD127+) were measured with flow cytometry. Interferon γ, interleukin 12 (IL-12), and IL-10 mRNAs were also quantified in whole spleen cells and purified B cells (CD43−) with real-time qPCR. Our data suggest that a B-cell subpopulation expressing IL-10 downregulated proinflammatory cytokine expression in the spleen, increasing the survival of CD4+ TEM cells and CD8+ TEM/CD127+ cells. PMID:26397973

  7. An 8 Meter Monolithic UV/Optical Space Telescope

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Postman, Marc

    2008-01-01

    The planned Ares V launch vehicle with its 10 meter fairing and at least 55,600 kg capacity to Earth Sun L2 enables entirely new classes of space telescopes. A consortium from NASA, Space Telescope Science Institute, and aerospace industry are studying an 8-meter monolithic primary mirror UV/optical/NIR space telescope to enable new astrophysical research that is not feasible with existing or near-term missions, either space or ground. This paper briefly reviews the science case for such a mission and presents the results of an on-going technical feasibility study, including: optical design; structural design/analysis including primary mirror support structure, sun shade and secondary mirror support structure; thermal analysis; launch vehicle performance and trajectory; spacecraft including structure, propulsion, GN&C, avionics, power systems and reaction wheels; operations & servicing; mass budget and cost.

  8. Prism beamswitch for radio telescopes.

    PubMed

    Payne, J M; Ulich, B L

    1978-12-01

    A dielectric prism and switching mechanism have been constructed for beamswitching a Cassegrain radio telescope. Spatially extended radio sources may be mapped without significant confusion utilizing the sensitivity and stability inherent in the conventional Dicke radiometer.

  9. Automated telescope for variability studies

    NASA Astrophysics Data System (ADS)

    Ganesh, S.; Baliyan, K. S.; Chandra, S.; Joshi, U. C.; Kalyaan, A.; Mathur, S. N.

    PRL has installed a 50 cm telescope at Mt Abu, Gurushikhar. The backend instrument consists of a 1K × 1K EMCCD camera with standard UBVRI filters and also has polarization measurement capability using a second filter wheel with polaroid sheets oriented at different position angles. This 50 cm telescope observatory is operated in a robotic mode with different methods of scheduling of the objects being observed. This includes batch mode, fully manual as well as fully autonomous mode of operation. Linux based command line as well as GUI software are used entirely in this observatory. This talk will present the details of the telescope and associated instruments and auxiliary facilities for weather monitoring that were developed in house to ensure the safe and reliable operation of the telescope. The facility has been in use for a couple of years now and various objects have been observed. Some of the interesting results will also be presented.

  10. Anastigmatic three-mirror telescope

    NASA Technical Reports Server (NTRS)

    Korsch, D. G. (Inventor)

    1978-01-01

    A three-mirror telescope for extraterrestrial observations is described. An ellipsoidal primary mirror, a hyperbolic secondary mirror, and an ellipsoidal tertiary mirror, produce an image in a conveniently located finite plane for viewing.

  11. Space Telescope moving target tracking

    NASA Technical Reports Server (NTRS)

    Strikwerda, T. E.; Strohbehn, K.; Fowler, K. R.; Skillman, D. R.

    1985-01-01

    This paper formulates a Space Telescope (ST) moving target tracking algorithm and evaluates a practical implementation. The algorithm is shown to be satisfactory for tracking such moving objects as the moons of Mars.

  12. Large aperture Fresnel telescopes/011

    SciTech Connect

    Hyde, R.A., LLNL

    1998-07-16

    At Livermore we`ve spent the last two years examining an alternative approach towards very large aperture (VLA) telescopes, one based upon transmissive Fresnel lenses rather than on mirrors. Fresnel lenses are attractive for VLA telescopes because they are launchable (lightweight, packagable, and deployable) and because they virtually eliminate the traditional, very tight, surface shape requirements faced by reflecting telescopes. Their (potentially severe) optical drawback, a very narrow spectral bandwidth, can be eliminated by use of a second (much smaller) chromatically-correcting Fresnel element. This enables Fresnel VLA telescopes to provide either single band ({Delta}{lambda}/{lambda} {approximately} 0.1), multiple band, or continuous spectral coverage. Building and fielding such large Fresnel lenses will present a significant challenge, but one which appears, with effort, to be solvable.

  13. Hubble Space Telescope-Illustration

    NASA Technical Reports Server (NTRS)

    1989-01-01

    This illustration depicts a side view of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  14. The Large Binocular Telescope Project

    NASA Astrophysics Data System (ADS)

    Hill, J. M.

    1994-12-01

    The Large Binocular Telescope (LBT) Project has evolved from concepts first proposed in 1985. The present partners involved in the design and construction of this 2 x 8.4 meter binocular telescope are the University of Arizona, Italy represented by the Osservatorio Astronomico di Arcetri and the Research Corporation based in Tucson. These three partners have committed sufficient funds to build the enclosure and the telescope populated with a single 8.4 meter optical train --- approximately 40 million dollars (1989). Based on this commitment, design and construction activities are now moving forward. Additional partners are being sought. The next mirror to be cast at the Steward Observatory Mirror Lab in late fall 1995 will be the first borosilicate honeycomb primary for LBT. The baseline optical configuration of LBT includes wide field Cassegrain secondaries with optical foci above the primaries to provide a corrected one degree field at F/4. The infrared F/15 secondaries are a Gregorian design to allow maximum flexibility for adaptive optics. The F/15 secondaries are undersized to provide a low thermal background focal plane which is unvignetted over a 4 arcminute diameter field-of-view. The interferometric focus combining the light from the two 8.4 meter primaries will reimage two folded Gregorian focal planes to a central location. The telescope elevation structure accommodates swing arms which allow rapid interchange of the various secondary and tertiary mirrors. Maximum stiffness and minimal thermal disturbance continue to be important drivers for the detailed design of the telescope. The telescope structure accommodates installation of a vacuum bell jar for aluminizing the primary mirrors in-situ on the telescope. The detailed design of the telescope structure will be completed in 1995 by ADS Italia (Lecco) and European Industrial Engineering (Mestre). The final enclosure design is now in progress at M3 Engineering (Tucson) and ADS Italia. Construction

  15. The Large Binocular Telescope Project

    NASA Astrophysics Data System (ADS)

    Hill, J. M.

    1995-05-01

    The Large Binocular Telescope (LBT) Project has evolved from concepts first proposed in 1985. The present partners involved in the design and construction of this 2 x 8.4 meter binocular telescope are the University of Arizona, Italy represented by the Osservatorio Astrofisico di Arcetri and the Research Corporation based in Tucson. These three partners have committed sufficient funds to build the enclosure and the telescope populated with a single 8.4 meter optical train --- approximately 40 million dollars (1989). Based on this commitment, design and construction activities are now moving forward. Additional partners are being sought. The next mirror to be cast at the Steward Observatory Mirror Lab in spring of 1996 will be the first borosilicate honeycomb primary for LBT. The baseline optical configuration of LBT includes wide field Cassegrain secondaries with optical foci above the primaries to provide a corrected one degree field at F/4. The infrared F/15 secondaries are a Gregorian design to allow maximicrons flexibility for adaptive optics. The F/15 secondaries are undersized to provide a low thermal background focal plane which is unvignetted over a 4 arcminute diameter field-of-view. The interferometric focus combining the light from the two 8.4 meter primaries will reimage two folded Gregorian focal planes to a central location. The telescope elevation structure accommodates swing arms which allow rapid interchange of the various secondary and tertiary mirrors. Maximicrons stiffness and minimal thermal disturbance continue to be important drivers for the detailed design of the telescope. The telescope structure accommodates installation of a vacuum bell jar for aluminizing the primary mirrors in-situ on the telescope. The detailed design of the telescope structure will be completed in 1995 by ADS Italia (Lecco) and European Industrial Engineering (Mestre). The final enclosure design is now in progress at M3 Engineering (Tucson) and ADS Italia

  16. Hubble Space Telescope-Illustration

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This is a cutaway illustration of the Hubble Space Telescope (HST) with callouts. The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  17. Hubble Space Telescope-Concept

    NASA Technical Reports Server (NTRS)

    1986-01-01

    This is an artist's concept of the Hubble Space Telescope (HST). The HST is the product of a partnership between NASA, European Space Agency Contractors, and the international community of astronomers. It is named after Edwin P. Hubble, an American Astronomer who discovered the expanding nature of the universe and was the first to realize the true nature of galaxies. The purpose of the HST, the most complex and sensitive optical telescope ever made, is to study the cosmos from a low-Earth orbit. By placing the telescope in space, astronomers are able to collect data that is free of the Earth's atmosphere. The HST detects objects 25 times fainter than the dimmest objects seen from Earth and provides astronomers with an observable universe 250 times larger than is visible from ground-based telescopes, perhaps as far away as 14 billion light-years. The HST views galaxies, stars, planets, comets, possibly other solar systems, and even unusual phenomena such as quasars, with 10 times the clarity of ground-based telescopes. The major elements of the HST are the Optical Telescope Assembly (OTA), the Support System Module (SSM), and the Scientific Instruments (SI). The HST is approximately the size of a railroad car, with two cylinders joined together and wrapped in a silvery reflective heat shield blanket. Wing-like solar arrays extend horizontally from each side of these cylinders, and dish-shaped anternas extend above and below the body of the telescope. The HST was deployed from the Space Shuttle Discovery (STS-31 mission) into Earth orbit in April 1990. The Marshall Space Flight Center had responsibility for design, development, and construction of the HST. The Perkin-Elmer Corporation, in Danbury, Connecticut, developed the optical system and guidance sensors. The Lockheed Missile and Space Company of Sunnyvale, California produced the protective outer shroud and spacecraft systems, and assembled and tested the finished telescope.

  18. Imaging phased telescope array study

    NASA Technical Reports Server (NTRS)

    Harvey, James E.

    1989-01-01

    The problems encountered in obtaining a wide field-of-view with large, space-based direct imaging phased telescope arrays were considered. After defining some of the critical systems issues, previous relevant work in the literature was reviewed and summarized. An extensive list was made of potential error sources and the error sources were categorized in the form of an error budget tree including optical design errors, optical fabrication errors, assembly and alignment errors, and environmental errors. After choosing a top level image quality requirment as a goal, a preliminary tops-down error budget allocation was performed; then, based upon engineering experience, detailed analysis, or data from the literature, a bottoms-up error budget reallocation was performed in an attempt to achieve an equitable distribution of difficulty in satisfying the various allocations. This exercise provided a realistic allocation for residual off-axis optical design errors in the presence of state-of-the-art optical fabrication and alignment errors. Three different computational techniques were developed for computing the image degradation of phased telescope arrays due to aberrations of the individual telescopes. Parametric studies and sensitivity analyses were then performed for a variety of subaperture configurations and telescope design parameters in an attempt to determine how the off-axis performance of a phased telescope array varies as the telescopes are scaled up in size. The Air Force Weapons Laboratory (AFWL) multipurpose telescope testbed (MMTT) configuration was analyzed in detail with regard to image degradation due to field curvature and distortion of the individual telescopes as they are scaled up in size.

  19. BCK Network of Optical Telescopes

    NASA Astrophysics Data System (ADS)

    McGruder, Charles H.; Antoniuk, Krill; Carini, Michael T.; Gelderman, Richard; Hammond, Benjamin; Hicks, Stacy; Laney, David; Shakhovskoy, David; Strolger, Louis-Gregory; Williams, Joshua

    2015-01-01

    The BCK network consists of three research grade telescopes: 0.6m (B) at the Bell Observatory near Western Kentucky University (WKU), 1.3m (C) at the Crimean Astrophysical Observatory and a 1.3m (K) at Kitt Peak National Observatory. The Bell Telescope is operated remotely from WKU while the Robotically Controlled Telescope (RCT) at Kitt Peak possesses an autonomous scheduler. The BCK telescopes are distributed longitudinally over 145º and can be used to observe continuously up to 21.2 hours/day. The network will be chiefly employed to observe variable stars, blazars and unpredictable celestial events.Because celestial objects with ground-based telescopes cannot be observed optically during the daytime, continuous ground-based astronomical observations are only possible via a network of longitudinally distributed telescopes. When the sun rises in Crimea after it sets at Bell, continuous observations are possible. This occurs for about six and ½ months per year - mid September to early April. A network is highly desirable for events that are not predictable for instance the appearance of supernovae, gamma-ray bursts, or undiscovered exoplanetsVariable stars are really only known in significant numbers to about 14 mag. But, as the magnitude increases the number of stars in any field increases very sharply, so there are many variable stars to discover at faint magnitude (m > 14). Discovering new variables makes great undergraduate student projects, a major component of astronomical research at WKU. In addition, pinning down the periods of variable stars is greatly facilitated with a network of telescopes.The BCK telescope network will also be used for monitoring the optical variability of blazars. The network provides increased coverage on daily variability timescales by minimizing interruptions due to weather and or mechanical problems at any one observatory and is used for obtaining continuous (12+ hours) of observations of rapid variability in blazars which would

  20. Demonstration Telescopes Using "Dollar Optics"

    NASA Astrophysics Data System (ADS)

    Ross, Paul

    2008-05-01

    I propose a poster that illustrates the use of "dollar optics” for experimentation and for the creation of demonstration telescopes. Handling a variety of lenses and mirrors provides an opportunity for discovering practical optics. Some part of this path of exploration must have been traveled by Galileo as he experimented with spectacle lenses. "Dollar optics” include reading glasses (positive meniscus lenses), convex and concave mirrors, Fresnel sheets, magnifying lenses, and eye loupes. Unwanted distance spectacles (negative meniscus lenses) are available at second-hand stores. Galileo telescopes, "long” 17th century telescopes, and useful demonstration models of Newtonian reflectors can be made with "dollar” optics. The poster will illustrate practical information about "dollar optics” and telescopes: magnification, focal length, and "diopters” disassembling spectacles; creating cheap mounts for spectacle lenses; the importance of optical axes and alignment; eyepieces; and focusing. (A table would be useful with the poster to set out a hands-on display of "dollar optic” telescopes.) Educators, experimenters, and those concerned with astronomy outreach might be interested in this poster. Working with "dollar optics” requires facility with simple tools, interest in planning projects, patience, imagination, and the willingness to invest some time and effort. "Dollar optics” may help to foster creativity and hands-on enthusiasm - as did Galileo's work with simple lenses 400 years ago. "Oh! When will there be an end put to the new observations and discoveries of this admirable instrument?” - Galileo Galilei as quoted by Henry C. King, The History of the Telescope.

  1. SLAS Library Telescope Program (Abstract)

    NASA Astrophysics Data System (ADS)

    Small, J. S.

    2016-12-01

    (Abstract only) In the fall of 2014, I submitted to the members of the St. Louis Astronomical Society to take the $1,000 profit we had from a convention we had hosted and use it to purchase three telescopes to modify for a Library Telescope program that was invented by Mark Stowbridge and promoted by the New Hampshire Astronomical Society. I had met Mark at NEAF in 2012 when he was walking the floor demonstrating the telescope. We held meetings with three libraries, the St. Louis County Library system, the St. Louis Public Library system and an independent library in Kirkwood, Missouri. The response was overwhelming! SLCL responded with a request for ten telescopes and SLPL asked for five. We did our first build in October, 2014 and placed a total of eighteen telescopes. Since that time, SLAS has placed a total of eighty-eight telescopes in library systems around the St. Louis Metro area, expanding into neighboring counties and across the river in Illinois. In this talk, I will discuss how to approach this project and put it in place in your libraries!

  2. SOFIA: Flying the Telescope

    NASA Technical Reports Server (NTRS)

    Asher, Troy A.; Cumming, Stephen B.

    2012-01-01

    and a proof of concept mission for which SOFIA was opportunely positioned is showcased. Success on this time-critical mission to observe a rare astronomical event proved the usefulness of an airborne observatory and the value in waiting for the capability provided by SOFIA. Finally, lessons learned in the test program are presented with emphasis on how lessons from previous aircraft and successful test programs were applied to SOFIA. Effective application of these lessons was crucial to the success of the SOFIA flight test program. SOFIA is an international cooperative program between NASA and the German Space Agency, DLR. It is a 2.5 meter (100-inch) telescope mounted in a Boeing 747SP aircraft used for astronomical observations at altitudes above 35,000 feet. SOFIA will accommodate a host of scientific instruments from the international science community and has a planned operational lifespan of more than 20 years.

  3. Reconstructing the 3D fracture distribution model from core (10 cm) to outcrop (10 m) and lineament (10 km) scales

    NASA Astrophysics Data System (ADS)

    Darcel, C.; Davy, P.; Bour, O.; de Dreuzy, J.

    2006-12-01

    model from both outcrop and well fracturing observations, and we discuss the consistency between the along-core fracturing intensity profile, the outcrop fracture traces, and the lineament maps. In the Forsmark site investigated by SKB, we conclude that the power-law distribution model is statistically consistent from core scale (80 mm) to outcrop scale (~10 m); the consistency with the lineament scale (10 km) is still questionable. An important subhorizontal fracturing exists at shallow depth, but it does not seems to affect the statistics of highly dipping fractures.

  4. The Swift Ultra-Violet/Optical Telescope

    NASA Astrophysics Data System (ADS)

    Roming, Peter; Hunsberger, Sally; Nousek, John; Ivanushkina, Mariya; Mason, Keith; Breeveld, Alice; Gehrels, Neil

    2004-05-01

    The Ultra-Violet/Optical Telescope (UVOT) is one of three telescopes on board the Swift Gamma-Ray Burst Mission. It supplies the Swift mission with the ability to detect the early UV and optical photons of GRB afterglows. The UVOT is of a modified Ritchey-Chrétien design with MCP intensified CCD detectors that provide sub-arcsecond resolution while operating in both a photon-timing and an imaging mode. A filter wheel accommodates broadband UV and visual filters for determining photometric redshifts in the range of 1.5 < z < 4.4. The filter wheel also houses UV and visual grisms for low-resolution spectroscopy. The UVOT will help answer questions about GRBs such as: how many times has reionization occurred in the Universe; what is the nature of dark bursts; what is the initial Lorentz factor of the fireball; and are there subclasses or new classes of GRBs? This work is sponsored at Penn State by NASA's Office of Space Science through contract NAS5-00136, and at MSSL by funding from PPARC.

  5. Virtualizing observation computing infrastructure at Subaru Telescope

    NASA Astrophysics Data System (ADS)

    Jeschke, Eric; Inagaki, Takeshi; Kackley, Russell; Schubert, Kiaina; Tait, Philip

    2016-08-01

    Subaru Telescope, an 8-meter class optical telescope located in Hawaii, has been using a high-availability commodity cluster as a platform for our Observation Control System (OCS). Until recently, we have followed a tried-and-tested practice of running the system under a native (Linux) OS installation with dedicated attached RAID systems and following a strict cluster deployment model to facilitate failover handling of hardware problems,1.2 Following the apparent benefits of virtualizing (i.e. running in Virtual Machines (VMs)) many of the non- observation critical systems at the base facility, we recently began to explore the idea of migrating other parts of the observatory's computing infrastructure to virtualized systems, including the summit OCS, data analysis systems and even the front ends of various Instrument Control Systems. In this paper we describe our experience with the initial migration of the Observation Control System to virtual machines running on the cluster and using a new generation tool - ansible - to automate installation and deployment. This change has significant impacts for ease of cluster maintenance, upgrades, snapshots/backups, risk-management, availability, performance, cost-savings and energy use. In this paper we discuss some of the trade-offs involved in this virtualization and some of the impacts for the above-mentioned areas, as well as the specific techniques we are using to accomplish the changeover, simplify installation and reduce management complexity.

  6. FERMI LARGE AREA TELESCOPE SECOND SOURCE CATALOG

    SciTech Connect

    Nolan, P. L.; Ajello, M.; Allafort, A.; Bechtol, K.; Berenji, B.; Blandford, R. D.; Bloom, E. D.; Abdo, A. A.; Ackermann, M.; Antolini, E.; Bonamente, E.; Atwood, W. B.; Belfiore, A.; Axelsson, M.; Baldini, L.; Bellazzini, R.; Ballet, J.; Bastieri, D.; Bignami, G. F. E-mail: Gino.Tosti@pg.infn.it E-mail: tburnett@u.washington.edu; and others

    2012-04-01

    We present the second catalog of high-energy {gamma}-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24 month period. The second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in five energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100 MeV to 100 GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely {gamma}-ray-producing source classes.

  7. Fermi Large Area Telescope Second Source Catalog

    NASA Technical Reports Server (NTRS)

    Nolan, P. L.; Abdo, A. A.; Ackermann, M.; Ajello, M; Allafort, A.; Antolini, E; Bonnell, J.; Cannon, A.; Celik O.; Corbet, R.; Davis, D. S.; DeCesar, M. E.; Ferrara, E. C.; Gehrels, N.; Harding, A. K.; Hays, E.; Johnson, T. E.; McConville, W.; McEnery, J. E; Perkins, J. S.; Racusin, J. L; Scargle, J. D.; Stephens, T. E.; Thompson, D. J.; Troja, E.

    2012-01-01

    We present the second catalog of high-energy gamma-ray sources detected by the Large Area Telescope (LAT), the primary science instrument on the Fermi Gamma-ray Space Telescope (Fermi), derived from data taken during the first 24 months of the science phase of the mission, which began on 2008 August 4. Source detection is based on the average flux over the 24-month period. The Second Fermi-LAT catalog (2FGL) includes source location regions, defined in terms of elliptical fits to the 95% confidence regions and spectral fits in terms of power-law, exponentially cutoff power-law, or log-normal forms. Also included are flux measurements in 5 energy bands and light curves on monthly intervals for each source. Twelve sources in the catalog are modeled as spatially extended. We provide a detailed comparison of the results from this catalog with those from the first Fermi-LAT catalog (1FGL). Although the diffuse Galactic and isotropic models used in the 2FGL analysis are improved compared to the 1FGL catalog, we attach caution flags to 162 of the sources to indicate possible confusion with residual imperfections in the diffuse model. The 2FGL catalog contains 1873 sources detected and characterized in the 100 11eV to 100 GeV range of which we consider 127 as being firmly identified and 1171 as being reliably associated with counterparts of known or likely gamma-ray-producing source classes.

  8. DKIST telescope mount factory testing overview and lessons learned

    NASA Astrophysics Data System (ADS)

    Jeffers, Paul; Trieloff, Todd; Kärcher, Hans; Seubert, Steffen; McBride, William

    2016-07-01

    The Daniel K Inouye Solar Telescope (DKIST) will be the largest solar telescope in the world, and will be able to provide the sharpest views ever taken of the solar surface. The telescope has a 4m aperture primary mirror, however due to the off axis nature of the optical layout, the telescope Mount has proportions similar to an 8 metre class telescope. The Telescope Mount Assembly (TMA) includes both the telescope Mount and the 16m diameter laboratory table or Coudé Rotator. The Coudé Rotator supports the full instrument suite of up to 40 tonnes and has full rotation capabilities similar to the Mount azimuth axis. The TMA has been going through the design, fabrication and assembly process since 2009 with Ingersoll Machine Tool's and this culminated with the Factory Acceptance Testing (FAT). The preparation for the FAT started not long after the Final Design Review was complete and planning continued through the assembly stages. The official Factory Acceptance testing of the Coudé Rotator was conducted during May/Jun 2014 and the Mount in Feb through Apr 2015. This paper provides an overview and discussion of the testing that was carried out. The depth and extent of testing will be described with discussion on what we would do differently next time. Also details of the preparation / process that lead into the testing will be presented. Most importantly the results will be summarized and lessons learned during the testing provided as well as discussion on how this influences the planned site assembly and extent of re-test post assembly.

  9. Adaptive Optics at the World's Biggest Optical Telescope

    NASA Astrophysics Data System (ADS)

    Hart, M.; Esposito, S.; Rabien, S.

    2010-09-01

    The Large Binocular Telescope (LBT) on Mt. Graham, Arizona, comprises two 8.4 m primary mirrors on a common mount. The two apertures will be co-phased to create a single telescope with 110 m2 of collecting area and 22.7 m baseline. From the outset, adaptive optics (AO) was incorporated into the design through two adaptive secondary mirrors (ASM), each 91 cm in diameter with 672 actuators, which feed all of the instruments mounted at the telescope's four pairs of Gregorian foci. The first ASM has now seen first light on sky with natural guide stars. Strehl ratios at 1.6 μm under average seeing are estimated to be ~80%, and diffraction-limited performance is maintained for stars down to magnitude 15. At the same time, pioneering work at the 6.5 m MMT telescope has for the first time shown the compelling benefits of ground-layer AO compensation. This technique relies on the signals from multiple laser beacons to sense and correct aberration arising close to the telescope with the result that near IR seeing is reduced by a factor of 2-3 over a field of many arc minutes. Building on these efforts at both telescopes, a project is underway to enhance the LBT's AO capability by the addition of wavefront sensing with multiple laser guide stars. The Advanced Rayleigh Ground-layer adaptive Optics System (ARGOS) is now in the construction phase. We provide an overview of ARGOS and how it foreshadows AO systems destined for the 30 m class telescopes of tomorrow.

  10. Life Extension Activities for the Hubble Space Telescope

    NASA Technical Reports Server (NTRS)

    Walyus, Keith D.; Pepe, Joyce A. K.; Prior, Michael

    2004-01-01

    With the cancellation of the Hubble Space Telescope (HST) Servicing Mission 4 (SM4), the HST Project will face numerous challenges to keep the Telescope operating during the remainder of the decade. As part of the SM4, the HST Project had planned to install various upgrades to the Telescope including the installation of new batteries and new rate integrating gyros. Without these upgrades, reliability analysis indicates that the spacecraft will lose the capability to conduct science operations later this decade. The HST team will be severely challenged to maximize the Telescope's remaining operational lifetime, while still trying to maximize - its science output and quality. Two of the biggest areas of concern are the age and condition of the batteries and gyros. Together they offer the largest potential extension in Telescope lifetime and present the biggest challenges to the HST team. The six Ni-H batteries on HST are the original batteries from launch. With fourteen years of operational life, these batteries have collectively lasted longer than any other comparable mission. Yet as with all batteries, their capacity has been declining. Engineers are examining various methods to prolong the life of these mission critical batteries, and retard the rate of degradation. This paper will focus on these and other efforts to prolong the life of the HST, thus enabling it to remain a world-class observatory for as long as possible.

  11. Ideas for future large single dish radio telescopes

    NASA Astrophysics Data System (ADS)

    Kärcher, Hans J.; Baars, Jacob W. M.

    2014-07-01

    The existing large single dish radio telescopes of the 100m class (Effelsberg, Green Bank) were built in the 1970s and 1990s. With some active optics they work now down to 3 millimeter wavelength where the atmospheric quality of the site is also a limiting factor. Other smaller single dish telescopes (50m LMT Mexico, 30m IRAM Spain) are located higher and reach sub-millimeter quality, and the much smaller 12m antennas of the ALMA array reach at a very high site the Terahertz region. They use advanced technologies as carbon fiber structures and flexible body control. We review natural limits to telescope design and use the examples of a number of telescopes for an overview of the available state-of-the-art in design, engineering and technologies. Without considering the scientific justification we then offer suggestions to realize ultimate performance of huge single dish telescopes (up to 160m). We provide an outlook on design options, technological frontiers and cost estimates.

  12. The Carlsberg Meridian Telescope: an astrometric robotic telescope

    NASA Astrophysics Data System (ADS)

    Evans, D. W.

    2001-12-01

    An overview is given of the Carlsberg Meridian Telescope on La Palma, which is one of the oldest robotic telescopes, having started observing on La Palma in 1984. In the spring of 1997, a further stage of automation was made when we converted the telescope to remote operation. Since then, the telescope has been operated over the Internet from Britain, Denmark or Spain. In 1997, a CCD camera, operating in a drift-scan mode, was installed. A year later the telescope underwent a major upgrade and a larger 2k×2k CCD camera was installed, with a Sloan r' filter. With the new system, the magnitude limit is r'=17 and the positional accuracy is in the range 0.03'' to 0.05''. The main task of the project is to map the sky in the declination range -3o to +50o, with the aim of providing an astrometric and photometric catalogue that can accurately transfer the Hipparcos/Tycho reference frame to Schmidt plates. We will release the first data by the end of 2001. Using the photometric information, extinction data for La Palma is also provided.

  13. The Carlsberg Meridian Telescope: An Astrometric Robotic Telescope

    NASA Astrophysics Data System (ADS)

    Evans, Dafydd Wyn

    An overview is given of the Carlsberg Meridian Telescope on La Palma, which is one of the oldest robotic telescopes, having started observing in 1984. In the spring of 1997, a further stage of automation was made when we converted the telescope to remote operation. Since then, the telescope has been operated over the Internet from Britain, Denmark or Spain. Two years ago, the telescope underwent a major upgrade and a 2k×2k CCD camera was installed, with a Sloan r' filter, operating in a drift scan mode. With the new system, the magnitude limit is r'=17 and the positional accuracy is in the range 0.03'' to 0.05''. The main task of the project is to map the sky in the declination range -3o to +50o, with the aim of providing an astrometric and photometric catalogue that can accurately transfer the Hipparcos/Tycho reference frame to Schmidt plates. We will release the first data by the end of the year.

  14. James Webb Space Telescope: large deployable cryogenic telescope in space

    NASA Astrophysics Data System (ADS)

    Lightsey, Paul A.; Atkinson, Charles; Clampin, Mark; Feinberg, Lee D.

    2012-01-01

    The James Webb Space Telescope (JWST) is an infrared space telescope designed to explore four major science themes: first light and reionization, the assembly of galaxies, the birth of stars and protoplanetary systems, and planetary systems and origins of life. JWST is a segmented architecture telescope with an aperture of 6.6 m. It will operate at cryogenic temperature (40 K), achieved via passive cooling, in an orbit about the Earth-Sun second Lagrange point (L2). Passive cooling is facilitated by means of a large sunshield that provides thermal isolation and protection from direct illumination from the Sun. The large size of the telescope and spacecraft systems require that they are stowed for launch in a configuration that fits the Ariane 5 fairing, and then deployed after launch. Routine wavefront sensing and control measurements are used to achieve phasing of the segmented primary mirror and initial alignment of the telescope. A suite of instruments will provide the capability to observe over a spectral range from 0.6- to 27-μm wavelengths with imaging and spectroscopic configurations. An overview is presented of the architecture and selected optical design features of JWST are described.

  15. Silicon pore optics for the ATHENA telescope

    NASA Astrophysics Data System (ADS)

    Collon, Maximilien J.; Vacanti, Giuseppe; Günther, Ramses; Yanson, Alex; Barriere, Nicolas; Landgraf, Boris; Vervest, Mark; Chatbi, Abdelhakim; van der Hoeven, Roy; Beijersbergen, Marco W.; Bavdaz, Marcos; Wille, Eric; Shortt, Brian; Haneveld, Jeroen; Koelewijn, Arenda; van Baren, Coen; Eigenraam, Alexander; Müller, Peter; Krumrey, Michael; Burwitz, Vadim; Pareschi, Giovanni; Conconi, Paolo; Massahi, Sonny; Christensen, Finn E.; Valsecchi, Giuseppe

    2016-07-01

    Silicon Pore Optics is a high-energy optics technology, invented to enable the next generation of high-resolution, large area X-ray telescopes such as the ATHENA observatory, a European large (L) class mission with a launch date of 2028. The technology development is carried out by a consortium of industrial and academic partners and focuses on building an optics with a focal length of 12 m that shall achieve an angular resolution better than 5". So far we have built optics with a focal length of 50 m and 20 m. This paper presents details of the work carried out to build silicon stacks for a 12 m optics and to integrate them into mirror modules. It will also present results of x-ray tests taking place at PTB's XPBF with synchrotron radiation and the PANTER test facility.

  16. LISA Telescope Spacer Design Issues

    NASA Technical Reports Server (NTRS)

    Livas, Jeff; Arsenovic, P.; Catelluci, K.; Generie, J.; Howard, J.; Stebbins, Howard R.; Preston, A.; Sanjuan, J.; Williams, L.; Mueller, G.

    2010-01-01

    The LISA mission observes gravitational waves by measuring the separations between freely floating proof masses located 5 million kilometers apart with an accuracy of - 10 picometers. The separations are measured interferometrically. The telescope is an afocal Cassegrain style design with a magnification of 80x. The entrance pupil has a 40 cm diameter and will either be centered on-axis or de-centered off-axis to avoid obscurations. Its two main purposes are to transform the small diameter beam used on the optical bench to a diffraction limited collimated beam to efficiently transfer the metrology laser between spacecraft, and to receive the incoming light from the far spacecraft. It transmits and receives simultaneously. The basic optical design and requirements are well understood for a conventional telescope design for imaging applications, but the LISA design is complicated by the additional requirement that the total optical path through the telescope must remain stable at the picometer level over the measurement band during the mission to meet the measurement accuracy. We describe the mechanical requirements for the telescope and the preliminary work that has been done to understand the materials and mechanical issues associated with the design of a passive metering structure to support the telescope and to maintain the spacing between the primary and secondary mirrors in the LISA on-orbit environment. This includes the requirements flowdown from the science goals, thermal modeling of the spacecraft and telescope to determine the expected temperature distribution, layout options for the telescope including an on- and off-axis design. Plans for fabrication and testing will be outlined.

  17. Preliminary LISA Telescope Spacer Design

    NASA Technical Reports Server (NTRS)

    Livas, J.; Arsenovic, P.; Catellucci, K.; Generie, J.; Howard, J.; Stebbins, R. T.

    2010-01-01

    The Laser Interferometric Space Antenna (LISA) mission observes gravitational waves by measuring the separations between freely floating proof masses located 5 million kilometers apart with an accuracy of approximately 10 picometers. The separations are measured interferometrically. The telescope is an afocal Cassegrain style design with a magnification of 80x. The entrance pupil has a 40 cm diameter and will either be centered on-axis or de-centered off-axis to avoid obscurations. Its two main purposes are to transform the small diameter beam used on the optical bench to a diffraction limited collimated beam to efficiently transfer the metrology laser between spacecraft, and to receive the incoming light from the far spacecraft. It transmits and receives simultaneously. The basic optical design and requirements are well understood for a conventional telescope design for imaging applications, but the LISA design is complicated by the additional requirement that the total optical path through the telescope must remain stable at the picometer level over the measurement band during the mission to meet the measurement accuracy. This poster describes the requirements for the telescope and the preliminary work that has been done to understand the materials and mechanical issues associated with the design of a passive metering structure to support the telescope and to maintain the spacing between the primary and secondary mirrors in the LISA on-orbit environment. This includes the requirements flowdown from the science goals, thermal modeling of the spacecraft and telescope to determine the expected temperature distribution,layout options for the telescope including an on- and off-axis design, and plans for fabrication and testing.

  18. ROBAST: Development of a ROOT-based ray-tracing library for cosmic-ray telescopes and its applications in the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Okumura, Akira; Noda, Koji; Rulten, Cameron

    2016-03-01

    We have developed a non-sequential ray-tracing simulation library, ROOT-basedsimulatorforraytracing (ROBAST), which is aimed to be widely used in optical simulations of cosmic-ray (CR) and gamma-ray telescopes. The library is written in C++, and fully utilizes the geometry library of the ROOT framework. Despite the importance of optics simulations in CR experiments, no open-source software for ray-tracing simulations that can be widely used in the community has existed. To reduce the dispensable effort needed to develop multiple ray-tracing simulators by different research groups, we have successfully used ROBAST for many years to perform optics simulations for the Cherenkov Telescope Array (CTA). Among the six proposed telescope designs for CTA, ROBAST is currently used for three telescopes: a Schwarzschild-Couder (SC) medium-sized telescope, one of SC small-sized telescopes, and a large-sized telescope (LST). ROBAST is also used for the simulation and development of hexagonal light concentrators proposed for the LST focal plane. Making full use of the ROOT geometry library with additional ROBAST classes, we are able to build the complex optics geometries typically used in CR experiments and ground-based gamma-ray telescopes. We introduce ROBAST and its features developed for CR experiments, and show several successful applications for CTA.

  19. James Webb Space Telescope Optical Telescope Element Mirror Coatings

    NASA Technical Reports Server (NTRS)

    Keski-Kuha, Ritva A.; Bowers, Charles W.; Quijada, Manuel A.; Heaney, James B.; Gallagher, Benjamin; McKay, Andrew; Stevenson, Ian

    2012-01-01

    James Webb Space Telescope (JWST) Optical Telescope Element (OTE) mirror coating program has been completed. The science goals of the JWST mission require a uniform, low stress, durable optical coating with high reflectivity over the JWST spectral region. The coating has to be environmentally stable, radiation resistant and compatible with the cryogenic operating environment. The large size, 1.52 m point to point, light weight, beryllium primary mirror (PM) segments and flawless coating process during the flight mirror coating program that consisted coating of 21 flight mirrors were among many technical challenges. This paper provides an overview of the JWST telescope mirror coating program. The paper summarizes the coating development program and performance of the flight mirrors.

  20. Impacts of tilling and covering treatments on the biosolids solar drying conversion from Class B to Class A

    Technology Transfer Automated Retrieval System (TEKTRAN)

    The objective of this study was to evaluate the effects of tillage and cover treatments of solar drying on the conversion of Class B treated sewage sludge to a Class A product. The experiments were performed over two years at Green Valley, Arizona in steel-constructed sand-filled drying beds of 1.0m...

  1. Large aperture millimeter/submillimeter telescope: which is more cost-effective, aperture synthesis telescope versus large single dish telescope?

    NASA Astrophysics Data System (ADS)

    Iguchi, Satoru; Saito, Masao

    2016-07-01

    The Atacama Large Millimeter/submillimeter Array (ALMA) consists of 66 antennas with the aperture equivalent to a 91-m diameter antenna. The Green Bank Telescope (GBT) is the world's largest, 100-m diameter telescope in the wavelength range of 3 mm to 30 cm. The Large Millimeter Telescope (LMT) will be the world's largest, 50-m diameter, steerable millimeter-wavelength telescope. The Cerro Chajnantor Atacama Telescope (CCAT) will be the world's largest, 25-m diameter, submillimeter-wavelength telescope. We will investigate advantages and disadvantages of both the aperture synthesis telescope and the large single-dish telescope taking the cost effectiveness into consideration, and will propose the design of antenna structure for a future telescope project at millimeter and submillimeter wavelengths.

  2. The Spitzer Space Telescope Mission

    NASA Technical Reports Server (NTRS)

    Werner, M. W.

    2005-01-01

    The Spitzer Space Telescope, NASA's Great Observatory for infrared astronomy, was launched 2003 August 25 and is returning excellent scientific data from its Earth-trailing solar orbit. Spitzer combines the intrinsic sensitivity achievable with a cryogenic telescope in space with the great imaging and spectroscopic power of modern detector arrays to provide the user community with huge gains in capability for exploration of the cosmos in the infrared. The observatory systems are largely performing as expected, and the projected cryogenic lifetime is about five years. Spitzer is thus both a scientific and a technical precursor to the infrared astronomy missions of the future. This very brief paper refers interested readers to several sets of recent publications which describe both the scientific and the technical features of Spitzer in detail. Note that, until 2003 December, Spitzer was known as the Space Infrared Telescope Facility (SIRTF).

  3. Quantum telescope: feasibility and constraints.

    PubMed

    Kurek, A R; Pięta, T; Stebel, T; Pollo, A; Popowicz, A

    2016-03-15

    The quantum telescope is a recent idea aimed at beating the diffraction limit of spaceborne telescopes and possibly other distant target imaging systems. There is no agreement yet on the best setup of such devices, but some configurations have already been proposed. In this Letter we characterize the predicted performance of quantum telescopes and their possible limitations. Our extensive simulations confirm that the presented model of such instruments is feasible and the device can provide considerable gains in the angular resolution of imaging in the UV, optical, and infrared bands. We argue that it is generally possible to construct and manufacture such instruments using the latest or soon to be available technology. We refer to the latest literature to discuss the feasibility of the proposed QT system design.

  4. Double Compton scatter telescope calibration

    NASA Technical Reports Server (NTRS)

    Dayton, B.; Simone, J.; Green, M.; Long, J.; Zanrosso, E.; Zych, A. D.; White, R. S.

    1981-01-01

    Calibration techniques for a medium energy gamma ray telescope are described. Gain calibration using Compton edge spectra involves comparisons of pulse height spectra with spectra simulated by a Monte Carlo computer code which includes Compton scattering and pair production, plural scattering and variable energy resolution, and cell size. The telescope considered comprises 56 cells of liquid scintillator in four size groups, with a total liquid volume of 325 l; each cell has its own photomultiplier tube. Energy and angular resolutions and the PMT gain calibration procedure are verified with double scatter data for monoenergetic gamma rays at a known location. Detection probabilities for any cell combination in the two telescope arrays are calculated per steradian as a function of the scattering for a number of different energies with a Van de Graaff accelerator.

  5. Feature-based telescope scheduler

    NASA Astrophysics Data System (ADS)

    Naghib, Elahesadat; Vanderbei, Robert J.; Stubbs, Christopher

    2016-07-01

    Feature-based Scheduler offers a sequencing strategy for ground-based telescopes. This scheduler is designed in the framework of Markovian Decision Process (MDP), and consists of a sub-linear online controller, and an offline supervisory control-optimizer. Online control law is computed at the moment of decision for the next visit, and the supervisory optimizer trains the controller by simulation data. Choice of the Differential Evolution (DE) optimizer, and introducing a reduced state space of the telescope system, offer an efficient and parallelizable optimization algorithm. In this study, we applied the proposed scheduler to the problem of Large Synoptic Survey Telescope (LSST). Preliminary results for a simplified model of LSST is promising in terms of both optimality, and computational cost.

  6. LSST telescope and site status

    NASA Astrophysics Data System (ADS)

    Gressler, William J.

    2016-07-01

    The Large Synoptic Survey Telescope (LSST) Project1 received its construction authorization from the National Science Foundation in August 2014. The Telescope and Site (T and S) group has made considerable progress towards completion in subsystems required to support the scope of the LSST science mission. The LSST goal is to conduct a wide, fast, deep survey via a 3-mirror wide field of view optical design, a 3.2-Gpixel camera, and an automated data processing system. The summit facility is currently under construction on Cerro Pachón in Chile, with major vendor subsystem deliveries and integration planned over the next several years. This paper summarizes the status of the activities of the T and S group, tasked with design, analysis, and construction of the summit and base facilities and infrastructure necessary to control the survey, capture the light, and calibrate the data. All major telescope work package procurements have been awarded to vendors and are in varying stages of design and fabrication maturity and completion. The unique M1M3 primary/tertiary mirror polishing effort is completed and the mirror now resides in storage waiting future testing. Significant progress has been achieved on all the major telescope subsystems including the summit facility, telescope mount assembly, dome, hexapod and rotator systems, coating plant, base facility, and the calibration telescope. In parallel, in-house efforts including the software needed to control the observatory such as the scheduler and the active optics control, have also seen substantial advancement. The progress and status of these subsystems and future LSST plans during this construction phase are presented.

  7. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Greenhouse, Matthew

    2008-01-01

    The James Webb Space Telescope is being developed by NASA in partnership with the European and Canadian space agencies for launch during 2013. This mission is expected to carry the legacy of discovery of the Hubble Space Telescope through the next decade, and is designed with unique capability to address key questions about formation of the first galaxies after the Big Bang, their subsequelet volution, and the formation of stars and planets within our own galaxy. This talk will present an overview of the mission science objectives and the status of the mission development.

  8. Superconductor lunar telescopes --Abstract only

    NASA Technical Reports Server (NTRS)

    Chen, P. C.; Pitts, R.; Shore, S.; Oliversen, R.; Stolarik, J.; Segal, K.; Hojaji, H.

    1994-01-01

    We propose a new type of telescope designed specifically for the lunar environment of high vacuum and low temperature. Large area UV-Visible-IR telescope arrays can be built with ultra-light-weight replica optics. High T(sub c) superconductors provide support, steering, and positioning. Advantages of this approach are light-weight payload compatible with existing launch vehicles, configurable large area optical arrays, no excavation or heavy construction, and frictionless electronically controlled mechanisms. We have built a prototype and will be demonstarting some of its working characteristics.

  9. Apollo Telescope Mount Spar Assembly

    NASA Technical Reports Server (NTRS)

    1969-01-01

    The Apollo Telescope Mount (ATM), designed and developed by the Marshall Space Flight Center, served as the primary scientific instrument unit aboard the Skylab. The ATM contained eight complex astronomical instruments designed to observe the Sun over a wide spectrum from visible light to x-rays. This image shows the ATM spar assembly. All solar telescopes, the fine Sun sensors, and some auxiliary systems are mounted on the spar, a cruciform lightweight perforated metal mounting panel that divides the 10-foot long canister lengthwise into four equal compartments. The spar assembly was nested inside a cylindrical canister that fit into the rack, a complex frame, and was protected by the solar shield.

  10. Wide field of view telescope

    DOEpatents

    Ackermann, Mark R.; McGraw, John T.; Zimmer, Peter C.

    2008-01-15

    A wide field of view telescope having two concave and two convex reflective surfaces, each with an aspheric surface contour, has a flat focal plane array. Each of the primary, secondary, tertiary, and quaternary reflective surfaces are rotationally symmetric about the optical axis. The combination of the reflective surfaces results in a wide field of view in the range of approximately 3.8.degree. to approximately 6.5.degree.. The length of the telescope along the optical axis is approximately equal to or less than the diameter of the largest of the reflective surfaces.

  11. The network of INTA telescopes

    NASA Astrophysics Data System (ADS)

    Cuesta, L.

    2008-06-01

    The Spanish Instituto Nacional de Técnica Aeroespacial has a network of three telescopes located at some of the best places for astronomy in mainland Spain. The first is at the Observatorio de Calar Alto in Almeria, at an altitude of more than 2100 m. The second is near Calatayud in Zaragoza, at the summit of a 1400-m high mountain. The last is on the campus of the Instituto Nacional de Técnica Aerospatial (INTA), in Madrid. The three telescopes are either 40 or 50 cm in diameter and will be available for communications and educational projects.

  12. Artificial Intelligence in Autonomous Telescopes

    NASA Astrophysics Data System (ADS)

    Mahoney, William; Thanjavur, Karun

    2011-03-01

    Artificial Intelligence (AI) is key to the natural evolution of today's automated telescopes to fully autonomous systems. Based on its rapid development over the past five decades, AI offers numerous, well-tested techniques for knowledge based decision making essential for real-time telescope monitoring and control, with minimal - and eventually no - human intervention. We present three applications of AI developed at CFHT for monitoring instantaneous sky conditions, assessing quality of imaging data, and a prototype for scheduling observations in real-time. Closely complementing the current remote operations at CFHT, we foresee further development of these methods and full integration in the near future.

  13. LISA telescope spacer design investigations

    NASA Astrophysics Data System (ADS)

    Sanjuan, Josep; Mueller, Guido; Livas, Jeffrey; Preston, Alix; Arsenovic, Petar; Castellucci, Kevin; Generie, Joseph; Howard, Joseph; Stebbins, Robin

    The Laser Interferometer Space Antenna (LISA) is a space-based gravitational wave observa-tory with the goal of observing Gravitational Waves (GWs) from astronomical sources in a frequency range from 30 µHz to 0.1 Hz. The detection of GWs at such low frequency requires measurements of distances at the pico-meter level between bodies separated by 5 million kilo-meters. The LISA mission consists of three identical spacecraft (SC) separated by 5 × 106 km forming an equilateral triangle. Each SC contains two optical assemblies and two vacuum en-closures housing one proof mass (PM) in geodesic (free fall) motion each. The two assemblies on one SC are each pointing towards an identical assembly on each of the other two SC to form a non-equal arm interferometer. The measurement of the GW strain is done by measuring the change in the length of the optical path between the PMs of one arm relative to the other arms caused by the pass of a GW. An important element of the Interferometric Measurement System (IMS) is the telescope which, on one hand, gathers the light coming from the far SC (˜100 pW) and, on the other hand, expands and collimates the small outgoing beam ( 1 W) and sends it to the far SC. Due to the very demanding sensitivity requirements care must be taken in the design and validation of the telescope not to degrade the IMS performance. For instance, the diameter of the telescope sets the the shot noise of the IMS and depends critically on the diameter of the primary and the divergence angle of the outgoing beam. As the telescope is rather fast telescope, the divergence angle is a critical function of the overall separation between the primary and secondary. Any long term changes of the distance of more than a a few micro-meter would be detrimental to the LISA mission. Similarly challenging are the requirements on the in-band path-length noise for the telescope which has to be kept below 1 pm Hz-1/2 in the LISA band. Different configurations (on-axis/off axis

  14. New Information about Old Telescopes

    NASA Astrophysics Data System (ADS)

    Van Helden, Albert

    2016-01-01

    It has long been known that the earliest telescopes were primitive, suffering from a number of defects such as spherical and chromatic aberrations, grinding and polishing errors, and poor quality glass. In the last two decades, much new information has been uncovered by the cooperation between historians and scientists. As a result, we now have a much better, and more complete, history of early telescopes, from spectacle lenses and the invention of the instrument to the demise of long-focus non-achromatic refractors and their replacement by reflectors in the eighteenth century. We can begin to quantify the properties of these early instruments, and the results are often surprising.

  15. Development of Large-Aperture, Light-Weight Fresnel Lenses for Gossamer Space Telescopes

    SciTech Connect

    Sham, D; Hyde, R; Weisberg, A; Early, J; Rushford, M; Britten, J

    2002-04-29

    In order to examine more distant astronomical objects, with higher resolution, future space telescopes require objectives with significantly larger aperture than presently available. NASA has identified a progression in size from the 2.4m aperture objective currently used in the HUBBLE space telescope[l,2], to 25m and greater in order to observe, e.g., extra-solar planets. Since weight is a crucial factor for any object sent into space, the relative weight of large optics over a given area must be reduced[3]. The areal mass density of the primary mirror for the Hubble space telescope is {approx}200 kg/m{sup 2}. This is expected to be reduced to around 15 kg/m{sup 2} for the successor to Hubble--the next generation space telescope (NGST)[4]. For future very large aperture telescopes needed for extra-solar planet detection, the areal mass density must be reduced even further. For example, the areal mass density goal for the Gossamer space telescopes is < 1 kg/m{sup 2}. The production of lightweight focusing optics at >10m size is also an enabling technology for many other applications such as Earth observation, power beaming, and optical communications.

  16. Cherenkov telescopes as optical telescopes for bright sources: today's specialized 30-m telescopes?

    NASA Astrophysics Data System (ADS)

    Lacki, Brian C.

    2011-10-01

    Imaging Atmospheric Cherenkov Telescopes (IACTs) use large-aperture (3-30 m) optical telescopes with arcminute angular resolution to detect TeV gamma-rays in the atmosphere. I show that IACTs are well suited for optical observations of bright sources (V≲ 8-10), because these sources are brighter than the sky background. Their advantages are especially great on rapid time-scales. Thus, IACTs might study many phenomena optically, including transiting exoplanets and the brightest gamma-ray bursts. In principle, an IACT could achieve millimagnitude photometry of these objects with second-long exposures. I also consider the potential for optical spectroscopy with IACTs, finding that their poor angular resolution limits their usefulness for high spectral resolutions, unless complex instruments are developed. The high photon collection rate of IACTs is potentially useful for precise polarimetry. Finally, I briefly discuss the broader possibilities of extremely large, low-resolution telescopes, including a 10 arcsec resolution telescope and space-borne telescopes.

  17. Physics and astrophysics with gamma-ray telescopes

    NASA Astrophysics Data System (ADS)

    Vandenbroucke, J.; Fermi LAT Collaboration

    2012-08-01

    In the past few years gamma-ray astronomy has entered a golden age. A modern suite of telescopes is now scanning the sky over both hemispheres and over six orders of magnitude in energy. At ˜TeV energies, only a handful of sources were known a decade ago, but the current generation of ground-based imaging atmospheric Cherenkov telescopes (H.E.S.S., MAGIC, and VERITAS) has increased this number to nearly one hundred. With a large field of view and duty cycle, the Tibet and Milagro air shower detectors have demonstrated the promise of the direct particle detection technique for TeV gamma rays. At ˜GeV energies, the Fermi Gamma-ray Space Telescope has increased the number of known sources by nearly an order of magnitude in its first year of operation. New classes of sources that were previously theorized to be gamma-ray emitters have now been confirmed observationally. Moreover, there have been surprise discoveries of GeV gamma-ray emission from source classes for which no theory predicted it was possible. In addition to elucidating the processes of high-energy astrophysics, gamma-ray telescopes are making essential contributions to fundamental physics topics including quantum gravity, gravitational waves, and dark matter. I summarize the current census of astrophysical gamma-ray sources, highlight some recent discoveries relevant to fundamental physics, and describe the synergetic connections between gamma-ray and neutrino astronomy. This is a brief overview intended in particular for particle physicists and neutrino astronomers, based on a presentation at the Neutrino 2010 conference in Athens, Greece. I focus in particular on results from Fermi (which was launched soon after Neutrino 2008), and conclude with a description of the next generation of instruments, namely HAWC and the Cherenkov Telescope Array.

  18. VISTA: Pioneering New Survey Telescope Starts Work

    NASA Astrophysics Data System (ADS)

    2009-12-01

    catalogues at data centres in the United Kingdom at the Universities of Cambridge and Edinburgh. All data will become public and be available to astronomers around the globe. Jim Emerson of Queen Mary, University of London and leader of the VISTA consortium, is looking forward to a rich harvest of science from the new telescope: "History has shown us some of the most exciting results that come out of projects like VISTA are the ones you least expect - and I'm personally very excited to see what these will be!" Notes [1] The VISTA Consortium is led by Queen Mary, University of London and consists of: Queen Mary, University of London; Queen's University of Belfast; University of Birmingham; University of Cambridge; Cardiff University; University of Central Lancashire; University of Durham; The University of Edinburgh; University of Hertfordshire; Keele University; Leicester University; Liverpool John Moores University; University of Nottingham; University of Oxford; University of St Andrews; University of Southampton; University of Sussex and University College London. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey

  19. Different cutoff values for 10-m walking speed simply classification of walking independence in stroke patients with or without cognitive impairment

    PubMed Central

    Yoshimoto, Yoshinobu; Oyama, Yukitsuna; Tanaka, Mamoru

    2015-01-01

    [Purpose] The aim of this study was to determine the threshold for classifying walking independence in stroke patients with and without cognitive disorders. [Subjects] The subjects were 130 patients with initial stroke hemiplegia. [Methods] The following factors were analyzed for associations with walking independence: Brunnstrom stage, one-leg standing time on the paralytic side, one-leg standing time on the non-paralytic side, and 10-m walking speed. We classified the patients with Mini-Mental State Examination (MMSE) scores ≥24 points into the high-score group and those with MMSE scores of ≤23 points into the low-score group and examined the main factors and cutoff values associated with walking independence in each group. [Results] The high-score group included 69 subjects (53.1%), and the low-score group included 61 subjects (46.9%). The primary factor associated with high MMSE scores among the stroke patients was the 10-m walking time. Using a cutoff level for the 10-m walking speed of 41.4 m/min resulted in a positive likelihood ratio of 6.3. The primary factor associated with low MMSE scores among the stroke patients was the 10-m walking time. Using a cutoff level for the 10-m walking speed of 48.0 m/min resulted in a positive likelihood ratio of 7.6. [Conclusion] The cutoff value for the 10-m walking speed can be used to evaluate walking independence in patients with stroke among patients with high or low MMSE scores. PMID:26157250

  20. Different cutoff values for 10-m walking speed simply classification of walking independence in stroke patients with or without cognitive impairment.

    PubMed

    Yoshimoto, Yoshinobu; Oyama, Yukitsuna; Tanaka, Mamoru

    2015-05-01

    [Purpose] The aim of this study was to determine the threshold for classifying walking independence in stroke patients with and without cognitive disorders. [Subjects] The subjects were 130 patients with initial stroke hemiplegia. [Methods] The following factors were analyzed for associations with walking independence: Brunnstrom stage, one-leg standing time on the paralytic side, one-leg standing time on the non-paralytic side, and 10-m walking speed. We classified the patients with Mini-Mental State Examination (MMSE) scores ≥24 points into the high-score group and those with MMSE scores of ≤23 points into the low-score group and examined the main factors and cutoff values associated with walking independence in each group. [Results] The high-score group included 69 subjects (53.1%), and the low-score group included 61 subjects (46.9%). The primary factor associated with high MMSE scores among the stroke patients was the 10-m walking time. Using a cutoff level for the 10-m walking speed of 41.4 m/min resulted in a positive likelihood ratio of 6.3. The primary factor associated with low MMSE scores among the stroke patients was the 10-m walking time. Using a cutoff level for the 10-m walking speed of 48.0 m/min resulted in a positive likelihood ratio of 7.6. [Conclusion] The cutoff value for the 10-m walking speed can be used to evaluate walking independence in patients with stroke among patients with high or low MMSE scores.

  1. LSST Telescope and Site Overview

    NASA Astrophysics Data System (ADS)

    Krabbendam, Victor; Claver, C. F.; Andrew, J.; Barr, J.; Gressler, W.; Kingsley, J.; Neill, D. R.; Olivier, S.; Sebag, J.; LSST Collaboration

    2007-12-01

    The LSST Telescope and Site has been designed to meet the stringent goals of the survey in terms of image quality and throughput. The telescope system delivers 0.25 arc sec FWHM seeing to the overall system image quality error budget. An active optics control system has been identified to measure wavefront quality in the focal plane and use this to reconstruct the figure and alignment errors in the optics. The primary-tertiary monolithic mirror is being fabricated at the Steward Observatory Mirror Lab using their structured borosilicate spin casting technology. Fabrication of the mold is underway, with "high fire” scheduled for spring 2008, and final delivery in late 2011. Baseline designs for active mirror support and optical testing for the monolith and conventional secondary mirror systems have been developed. The telescope is compact, stiff, and agile to maximize observing efficiency. The 300 ton structure can make 3.5 degree moves (at a 30 degree zenith angle) on the sky in less than 5 seconds. The dome will track and slew to follow the telescope pointing with minimal power. The summit facility has been designed to support operations and maintenance for minimal down time

  2. Neutrino telescopes in the World

    SciTech Connect

    Ernenwein, J.-P.

    2007-01-12

    Neutrino astronomy has rapidly developed these last years, being the only way to get specific and reliable information about astrophysical objects still poorly understood.Currently two neutrino telescopes are operational in the World: BAIKAL, in the lake of the same name in Siberia, and AMANDA, in the ices of the South Pole. Two telescopes of the same type are under construction in the Mediterranean Sea: ANTARES and NESTOR. All these telescopes belong to a first generation, with an instrumented volume smaller or equal to 0.02 km3. Also in the Mediterranean Sea, the NEMO project is just in its stag phase, within the framework of a cubic kilometer size neutrino telescope study. Lastly, the ICECUBE detector, with a volume reaching about 1 km3, is under construction on the site of AMANDA experiment, while an extension of the BAIKAL detector toward km3 is under study. We will present here the characteristics of these experiments, as well as the results of their observations.

  3. Hubble Space Telescope prescription retrieval.

    PubMed

    Redding, D; Dumont, P; Yu, J

    1993-04-01

    Prescription retrieval is a technique for directly estimating optical prescription parameters from images. We apply it to estimate the value of the Hubble Space Telescope primary mirror conic constant. Our results agree with other studies that examined primary-mirror test fixtures and results. In addition they show that small aberrations exist on the planetary-camera repeater optics.

  4. Fermi's Large Area Telescope (LAT)

    NASA Video Gallery

    Fermi’s Large Area Telescope (LAT) is the spacecraft’s main scientificinstrument. This animation shows a gamma ray (purple) entering the LAT,where it is converted into an electron (red) and a...

  5. Push-To Telescope Mathematics

    ERIC Educational Resources Information Center

    Teets, Donald

    2012-01-01

    Two coordinate systems are related here, one defined by the earth's equator and north pole, the other by the orientation of a telescope at some location on the surface of the earth. Applying an interesting though somewhat obscure property of orthogonal matrices and using the cross-product simplifies this relationship, revealing that a surprisingly…

  6. POST: a polar stratospheric telescope

    NASA Astrophysics Data System (ADS)

    Ford, Holland C.; Bely, Pierre Y.; Bally, John; Crocker, James H.; Dopita, Mike; Tilley, James N.; Allen, Ronald; Bartko, Frank; White, Richard L.; Burg, Richard; Burrows, Christopher J.; Clampin, Mark; Harper, Doyal A.; Illingworth, Garth; McCray, Richard; Meyer, Stephan; Mould, Jeremy; Norman, Colin

    1994-06-01

    The lower stratosphere in the polar regions offers conditions for observation in the near-infrared comparable to those obtained from space. We describe a concept for a 6-meter, diluted aperture, near-infrared telescope carried by a tethered aerostat flying at 12 km altitude, to serve as a testbed for future space astronomical observatories while producing frontier science.

  7. GISOT: a giant solar telescope

    NASA Astrophysics Data System (ADS)

    Hammerschlag, Robert H.; von der Lühe, Oskar F.; Bettonvil, Felix C.; Jägers, Aswin P.; Snik, Frans

    2004-10-01

    A concept is presented for an extremely large high-resolution solar telescope with an aperture of 11 m and diffraction limited for visual wavelengths. The structure of GISOT will be transparent to wind and placed on a transparent stiff tower. For efficient wind flushing, all optics, including the primary mirror, will be located above the elevation axis. The aperture will be of the order of 11 m, not rotatively symmetrical, but of an elongated shape with dimensions 11 x 4 m. It consists of a central on-axis 4 m mirror with on both sides 3 pieces of 2 m mirrors. The optical layout will be kept simple to guarantee quality and minimize stray light. A Coudé room for instruments is planned below the telescope. The telescope will not be housed in a dome-like construction, which interferes with the open principle. Instead the telescope will be protected by a foldable tent construction with a diameter of the order of 30 m, which doesn"t form any obstruction during observations, but can withstand the severe weather circumstances on mountain sites. Because of the nature of the solar scene, extremely high resolution in only one dimension is sufficient to solve many exciting problems in solar physics and in this respect the concept of GISOT is very promising.

  8. Neptune and Titan Observed with Keck Telescope Adaptive Optics

    SciTech Connect

    Max, C.E.; Macintosh, B.A.; Gibbard, S.; Gavel, D.T.; Roe, H.; De Pater, I.; Ghez, A.M.; Acton, S.; Wizinowich, P.L.; Lai, O.

    2000-05-05

    The authors report on observations taken during engineering science validation time using the new adaptive optics system at the 10-m Keck II Telescope. They observe Neptune and Titan at near-infrared wavelengths. These objects are ideal for adaptive optics imaging because they are bright and small, yet have many diffraction-limited resolution elements across their disks. In addition Neptune and Titan have prominent physical features, some of which change markedly with time. They have observed infrared-bright storms on Neptune, and very low-albedo surface regions on Titan, Saturn's largest moon, Spatial resolution on Neptune and Titan was 0.05-0.06 and 0.04-0.05 arc sec, respectively.

  9. Neptune and Titan observed with Keck Telescope adaptive optics

    NASA Astrophysics Data System (ADS)

    Max, Claire E.; Macintosh, Bruce A.; Gibbard, Seran; Gavel, Donald T.; Roe, Henry; de Pater, Imke; Ghez, Andrea M.; Acton, Scott; Wizinowich, Peter L.; Lai, Olivier

    2000-07-01

    We report on observations taken during engineering science validation time using the new adaptive optics system at the 10-m Keck II Telescope. We observed Neptune and Titan at near- infrared wavelengths. These objects are ideal for adaptive optics imaging because they are bright and small, yet have many diffraction-limited resolution elements across their disks. In addition Neptune and Titan have prominent physical features, some of which change markedly with time. We have observed infrared-bright 'storms' on Neptune, and very low- albedo surface regions on Titan, Saturn's largest moon. Spatial resolution on Neptune and Titan was 0.05 - 0.06 and 0.04 - 0.05 arc sec, respectively.

  10. Remote operation of telescopes - Long-distance observation

    NASA Astrophysics Data System (ADS)

    Ford, H. C.

    1982-10-01

    Communications, equipment, and siting and cost considerations for establishing a remotely controlled 10 m optical telescope on Mauna Kea to be operated by the University of California are discussed. The 13,800 ft elevation of the site permits clear viewing most of the year while simultaneously presenting a rarefied and cold atmosphere which can significantly degrade operator performance. A high-bandpass satellite communications link between researchers and operators located in California would permit both research and equipment diagnostics studies to be performed, as well as save travel expenses. A 500 kb/sec data transmission rate will furnish a live picture every five minutes via a 5 MHz bandpass. An on-site control room featuring a computer, tape drive, plotter, terminal, modem, and electronics will cost $54/mo if amortized over a 50 yr installation lifetime.

  11. The James Webb Space Telescope: Mission Overview and Status

    NASA Technical Reports Server (NTRS)

    Greenhouse, Matthew A.

    2011-01-01

    The James Webb Space Telescope (JWST) is the Infrared successor to the Hubble Space Telescope. It is a cryogenic infrared space observatory with a 25 sq m aperture (6 m class) telescope yielding diffraction limited angular resolution at a wave1ength of 2 micron. The science instrument payload includes three passively cooled near-infrared instruments providing broad- and narrow-band imagery, coronagraphy, as well as multi-object and integral-field spectroscopy over the 0.6 Telescope. Technology development and mission design are complete, and construction is underway in all areas of the program.

  12. The Thirty Meter Telescope (TMT): An International Observatory

    NASA Astrophysics Data System (ADS)

    Sanders, Gary H.

    2013-06-01

    The Thirty Meter Telescope (TMT) will be the first truly global ground-based optical/infrared observatory. It will initiate the era of extremely large (30-meter class) telescopes with diffraction limited performance from its vantage point in the northern hemisphere on Mauna Kea, Hawaii, USA. The astronomy communities of India, Canada, China, Japan and the USA are shaping its science goals, suite of instrumentation and the system design of the TMT observatory. With large and open Nasmyth-focus platforms for generations of science instruments, TMT will have the versatility and flexibility for its envisioned 50 years of forefront astronomy. The TMT design employs the filled-aperture finely-segmented primary mirror technology pioneered with the W.M. Keck 10-meter telescopes. With TMT's 492 segments optically phased, and by employing laser guide star assisted multi-conjugate adaptive optics, TMT will achieve the full diffraction limited performance of its 30-meter aperture, enabling unprecedented wide field imaging and multi-object spectroscopy. The TMT project is a global effort of its partners with all partners contributing to the design, technology development, construction and scientific use of the observatory. TMT will extend astronomy with extremely large telescopes to all of its global communities.

  13. Teaching remote observation using telescopes at Aras de los Olmos

    NASA Astrophysics Data System (ADS)

    Ballesteros, F. J.; Gutiérrez-Soto, J.

    2015-05-01

    The Observatorio de Aras de los Olmos (OAO) is the observation station of the Astronomical Observatory of the University of Valencia. It is located in the town of Aras de los Olmos on top of the Muela de Santa Catalina mountain, one of the few dark places in the Valencian Community. The OAO has three remotely operable telescopes, with sizes of 40, 50 and 60 cm. As a general purpose observatory and due to its variety in the available instrumentation, the OAO offers a great flexibility in its observations. Among other activities, the OAO telescopes becomes a top-rated first-class teaching resource. In this contribution we present the remote observation system of the OAO telescopes. This system allows direct interaction with telescopes for a large number of students, from the classroom or from their homes. Experience during 2013--14 academic year at the Valencian International University was very satisfactory. The Observatory is now considering offering this service to other universities.

  14. FORCAST Camera Installed on SOFIA Telescope

    NASA Video Gallery

    Cornell University's Faint Object Infrared Camera for the SOFIA Telescope, or FORCAST, being installed on the Stratospheric Observatory for Infrared Astronomy's 2.5-meter telescope in preparation f...

  15. Rangefinder Metrology for the Green Bank Telescope

    NASA Astrophysics Data System (ADS)

    Goldman, M. A.; Creager, R. E.; Parker, D. H.; Payne, J. A.

    A scanning laser rangefinder metrology system for the 100 meter Green Bank Telescope is described. Use of this system for correction of the primary reflector's shape and pointing of the telescope is described.

  16. Eclipse Photographs Through a Small Telescope

    NASA Astrophysics Data System (ADS)

    Kramer, Bill

    1999-08-01

    Results of previous eclipse photography using a small telescope (Questar 90mm x 1200mm EFL) and camera. During the presentation of images, tips and ideas for getting good pictures through a telescope will be discussed.

  17. Galileo, telescopic astronomy, and the Copernican system.

    NASA Astrophysics Data System (ADS)

    van Helden, A.

    Contents: 1. Introduction. 2. Telescopic discoveries. 3. Sunspots, Copernicanism, and theology. 4. The decree of 1616. 5. The Dialogue. 6. The trial of Galileo. 7. The aftermath of the trial. 8. Telescopic astronomy after Galileo.

  18. The mini-array of ASTRI SST-2M telescopes, precursors for the Cherenkov Telescope Array

    NASA Astrophysics Data System (ADS)

    Pareschi, Giovanni; Bonnoli, Giacomo; Vercellone, Stefano; ASTRI Collaboration; CTA Consortium

    2016-05-01

    In the framework of the Cherenkov Telescope Array (CTA) Observatory, the Italian National Institute of Astrophysics (INAF) has recently inaugurated in Sicily (Italy), at the Serra La Nave astronomical site on the slopes of Mount Etna, a large field of view (FoV, ~ 9.6°) dual-mirror prototype (ASTRI SST-2M) of the CTA small size class of telescopes (SST). The CTA plans to install about 70 SST in the southern site to allow the study of the gamma rays from a few TeV up to hundreds of TeV. The ASTRI SST-2M telescope prototype has been developed following an end-to-end approach, since it includes the entire system of structure, mirrors optics (primary and secondary mirrors), camera, and control/acquisition software. A remarkable performance improvement could come from the operation of the ASTRI mini-array, led by INAF in synergy with the Universidade de Sao Paulo (Brazil) and the North-West University (South Africa). The ASTRI mini-array will be composed of nine ASTRI SST-2M units and it is proposed as a precursor and initial seed of the CTA to be installed at the final CTA southern site. Apart from the assessment of a number of technological aspects related to the CTA, the ASTRI mini-array will, if compared for instance to H.E.S.S., extend the point source sensitivity up to ~ 100 TeV, also improving it above 5-10 TeV. Moreover, the unprecedented width of the FoV, with its homogeneous acceptance and angular resolution, will significantly contribute to the achievement of original results during the early CTA science phase.

  19. Project CLASS.

    ERIC Educational Resources Information Center

    McBain, Susan L.; And Others

    Project CLASS (Competency-Based Live-Ability Skills) uses a series of 60 modules to teach life survival skills to adults with low-level reading ability--especially Adult Basic Education/English as a Second Language students. Two versions of the modules have been developed: one for use with teacher-directed instruction and another for independent…

  20. Origins Space Telescope: Telescope Design and Instrument Specifications

    NASA Astrophysics Data System (ADS)

    Meixner, Margaret; Carter, Ruth; Leisawitz, David; Dipirro, Mike; Flores, Anel; Staguhn, Johannes; Kellog, James; Roellig, Thomas L.; Melnick, Gary J.; Bradford, Charles; Wright, Edward L.; Zmuidzinas, Jonas; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, one of the four science and technology definition studies of NASA Headquarters for the 2020 Astronomy and Astrophysics Decadal survey. The renaming of the mission reflects Origins science goals that will discover and characterize the most distant galaxies, nearby galaxies and the Milky Way, exoplanets, and the outer reaches of our Solar system. This poster will show the preliminary telescope design that will be a large aperture (>8 m in diameter), cryogenically cooled telescope. We will also present the specifications for the spectrographs and imagers over a potential wavelength range of ~10 microns to 1 millimeter. We look forward to community input into this mission definition over the coming year as we work on the concept design for the mission. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. We welcome you to contact the Science and Technology Definition Team (STDT) with your science needs and ideas by emailing us at firsurveyor_info@lists.ipac.caltech.edu.

  1. The National Large Solar Telescope (NLST) of India

    NASA Astrophysics Data System (ADS)

    Hasan, S. S.

    2012-12-01

    The Indian National Large Solar Telescope (NLST) will be a state-of-the-art 2-m class telescope for carrying out high-resolution studies in the solar atmosphere. Recent numerical simulations suggest that crucial physical processes like vortex flow, dissipation of magnetic fields and the generation of MHD waves can occur efficiently over length scales of tens of kilometers. Current telescopes are unable to resolve solar feature to this level at visible wavelengths. NLST will not only achieve good spatial resolution, but will also have a high photon throughput in order to carry out spectropolarimetric observations to accurately measure vector magnetic fields in the solar atmosphere with a good signal to noise ratio. The main science goals of NLST include: a) Magnetic field generation and the solar cycle; b) Dynamics of magnetized regions; c) Helioseismology; d) Long term variability; e) Energetic phenomena and Activity; and f) Night time astronomy. The optical design of the telescope is optimized for high optical throughput and uses a minimum number of optical elements. A high order adaptive optics system is integrated as part of the design that works with a modest Fried's parameter of 7-cm to give diffraction limited performance. The telescope will be equipped with a suite of post-focus instruments including a high resolution spectrograph and a polarimeter. NLST will also be used for carrying out stellar observations during the night. The mechanical design of the telescope, building, and the innovative dome takes advantage of the natural air flush which will help to keep the open telescope in temperature equilibrium. Critical to the successful implementation of NLST is the selection of a site with optimum atmospheric properties, such as the number of sunshine hours and good "seeing" over long periods. A site characterization programme carried over several years has established the existence of suitable sites in the Ladakh region. After its completion, currently

  2. The Carlina-type diluted telescope. Stellar fringes on Deneb

    NASA Astrophysics Data System (ADS)

    Le Coroller, H.; Dejonghe, J.; Hespeels, F.; Arnold, L.; Andersen, T.; Deram, P.; Ricci, D.; Berio, P.; Blazit, A.; Clausse, J.-M.; Guillaume, C.; Meunier, J. P.; Regal, X.; Sottile, R.

    2015-01-01

    new class of telescopes named large diluted telescopes. Its optical architecture has many advantages for future projects: Planet Formation Imager (PFI), post-ELTs, interferometer in space.

  3. The Hubble Space Telescope: Problems and Solutions.

    ERIC Educational Resources Information Center

    Villard, Ray

    1990-01-01

    Presented is the best understanding of the flaw discovered in the optics of the Hubble Space Telescope and the possible solutions to the problems. The spherical aberration in the telescope's mirror and its effect on the quality of the telescope's imaging ability is discussed. (CW)

  4. World atlas of large optical telescopes

    NASA Technical Reports Server (NTRS)

    Meszaros, S. P.

    1979-01-01

    By 1980 there will be approximately 100 large optical telescopes in the world with mirror or lens diameters of one meter (39 inches) and larger. This atlas gives information on these telescopes and shows their locations on continent-sized maps. Observatory locations considered suitable for the construction of future large telescopes are also shown.

  5. The Baker Observatory Robotic Autonomous Telescope

    NASA Astrophysics Data System (ADS)

    Hicks, L. L.; Reed, M. D.; Thompson, M. A.; Gilker, J. T.

    We describe the Baker Observatory Robotic Autonomous Telescope project. The hardware includes a 16 inch Meade LX-200 telescope, an AstroHaven 7 feet dome, an Apogee U47 CCD camera and filter wheel, a Boltwood Cloud Sensor II, and various other minor hardware. We are implementing RTS2 for the Telescope Control System and incorporating custom drivers for ancillary systems.

  6. First Light Adaptive Optics Images from the Keck II Telescope: A New Era of High Angular Resolution Imagery

    NASA Astrophysics Data System (ADS)

    Wizinowich, P.; Acton, D. S.; Shelton, C.; Stomski, P.; Gathright, J.; Ho, K.; Lupton, W.; Tsubota, K.; Lai, O.; Max, C.; Brase, J.; An, J.; Avicola, K.; Olivier, S.; Gavel, D.; Macintosh, B.; Ghez, A.; Larkin, J.

    2000-03-01

    Adaptive optics (AO) is a technology that corrects in real time for the blurring effects of atmospheric turbulence, in principle allowing Earth-bound telescopes to achieve their diffraction limit and to ``see'' as clearly as if they were in space. The power of AO using natural guide stars has been amply demonstrated in recent years on telescopes up to 3-4 m in diameter. The next breakthrough in astronomical resolution was expected to occur with the implementation of AO on the new generation of large, 8-10 m diameter telescopes. In this paper we report the initial results from the first of these AO systems, now coming on line on the 10 m diameter Keck II Telescope. The results include the highest angular resolution images ever obtained from a single telescope (0.022" and 0.040" at 0.85 and 1.65 μm wavelengths, respectively), as well as tests of system performance on three astronomical targets.

  7. Spitzer Space Telescope mission design

    NASA Technical Reports Server (NTRS)

    Kwok, Johnny H.; Garcia, Mark D.; Bonfiglio, Eugene; Long, Stacia M.

    2004-01-01

    This paper gives a description of the mission design, launch, orbit, and navigation results for the Spitzer space telescope mission. The Spitzer telescope was launched by the Delta II Heavy launch vehicle into a heliocentric Earth trailing orbit. This orbit is flown for the first time and will be used by several future astronomical missions such as Kepler, SIM, and LISA. This paper describes the launch strategy for a winter versus a summer launch and how it affects communications. It also describes how the solar orbit affects the design and operations of the Observatory. It describes the actual launch timeline, launch vehicle flight performance, and the long term behavior of the as flown orbit. It also provides the orbit knowledge from in-flight navigation data.

  8. Focusing X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    O'Dell, Stephen; Brissenden, Roger; Davis, William; Elsner, Ronald; Elvis, Martin; Freeman, Mark; Gaetz, Terrance; Gorenstein, Paul; Gubarev, Mikhall; Jerlus, Diab; Juda, Michael; Kolodziejczak, Jeffrey; Murray, Stephen; Petre, Robert; Podgorski, William; Ramsey, Brian; Reid, Paul; Saha, Timo; Wolk, Scott; Troller-McKinstry, Susan; Weisskopf, Martin; Wilke, Rudeger; Zhang, William

    2010-01-01

    During the half-century history of x-ray astronomy, focusing x-ray telescopes, through increased effective area and finer angular resolution, have improved sensitivity by 8 orders of magnitude. Here, we review previous and current x-ray-telescope missions. Next, we describe the planned next-generation x-ray-astronomy facility, the International X-ray Observatory (IXO). We conclude with an overview of a concept for the next next-generation facility, Generation X. Its scientific objectives will require very large areas (about 10,000 sq m) of highly-nested, lightweight grazing-incidence mirrors, with exceptional (about 0.1-arcsec) resolution. Achieving this angular resolution with lightweight mirrors will likely require on-orbit adjustment of alignment and figure.

  9. Kunlun Dark Universe Survey Telescope

    NASA Astrophysics Data System (ADS)

    Zhu, Yongtian; Wang, Lifan; Yuan, Xiangyan; Gu, Bozhong; Li, Xinnan; Yang, Shihai; Gong, Xuefei; Du, Fujia; Qi, Yongjun; Xu, Lingzhe

    2014-07-01

    Chinese Antarctic Observatory has been listed as National large research infrastructure during twelfth five-year plan. Kunlun Dark Universe Survey Telescope, one of two major facility of Chinese Antarctic Observatory, is a 2.5-meter optic/infrared telescope and will be built at the Chinese Antarctic Kunlun Station. It is intended to take advantage of the exceptional seeing conditions, as well as the low temperature reducing background for infrared observations. KDUST will adopt an innovative optical system, which can deliver very good image quality over a 2 square degree flat field of view. All of parts of it have been designed carefully to endure the extremely harsh environment. KDUST will be perched on a 14.5-meter-high tower to lift it above the turbulence layer. In this paper, preliminary design and key technology pre-research of KDUST will be introduced.

  10. Hubble Space Telescope Servicing begins.

    NASA Astrophysics Data System (ADS)

    1993-12-01

    The day's work began when astronauts Story Musgrave and Jeff Hoffman stepped out into the cargo bay at 9h41 pm CST, Saturday (4h41 am CET, Sunday). They immediately set to work replacing two gyroscope assemblies, known as the Rate Sensor Units, two associated electronics boxes, called Electronic Control Units, and eight electrical fuse plugs. The work was completed ahead of schedule, but the astronauts had trouble closing the doors of the compartment housing the gyros and took over an hour to get them shut. The astronauts also prepared equipment for the replacement of the solar arrays. "The feeling down here is one of great satisfaction for a tremendous job today" said spacecraft communicator Greg Harbaugh in mission control. "We are very proud of the work that you all did and we are very confident in the continued success of the mission. Everything is going great and tomorrow is going to be another great day". ESA astronaut Claude Nicollier played a vital role during the spacewalk moving the astronauts and their equipment around the cargo bay with the shuttle's robot arm. The Hubble Space Telescope servicing mission features more robot arm operations than any other shuttle flight. The telescope's left-hand solar array was rolled up successfully at 6h24 am CST (1h24 pm CET). The 11-tonne observatory was rotated 180 degrees on its turntable before commands were sent to retract the second array at 8h23 am CST (3h23 pm CET). The crew stopped the retraction when it appeared the system may have jammed. Mission control instructed the crew to jettison the array, a procedure that they have trained for. Tomorrow astronauts Kathy Thornton and Tom Akers will make a six-hour spacewalk to jettison the troublesome wing, store the other in the cargo bay, and install two new panels supplied by ESA. The second set of arrays feature thermal shields and a modified thermal compensation system to prevent the flexing that affected the first pair. The Hubble Space Telescope was plucked

  11. THE OPTIMAL GRAVITATIONAL LENS TELESCOPE

    SciTech Connect

    Surdej, J.; Hanot, C.; Sadibekova, T.; Delacroix, C.; Habraken, S.; Coleman, P.; Dominik, M.; Le Coroller, H.; Mawet, D.; Quintana, H.; Sluse, D.

    2010-05-15

    Given an observed gravitational lens mirage produced by a foreground deflector (cf. galaxy, quasar, cluster, ...), it is possible via numerical lens inversion to retrieve the real source image, taking full advantage of the magnifying power of the cosmic lens. This has been achieved in the past for several remarkable gravitational lens systems. Instead, we propose here to invert an observed multiply imaged source directly at the telescope using an ad hoc optical instrument which is described in the present paper. Compared to the previous method, this should allow one to detect fainter source features as well as to use such an optimal gravitational lens telescope to explore even fainter objects located behind and near the lens. Laboratory and numerical experiments illustrate this new approach.

  12. Telescoping Space-Station Modules

    NASA Technical Reports Server (NTRS)

    Witcofski, R. D.

    1986-01-01

    New telescoping-space-station design involves module within a module. After being carried to orbit within payload bay of Space Shuttle orbiter, outer module telescopically deployed to achieve nearly twice as much usable space-station volume per Space Shuttle launch. Closed-loop or "race-track" space-station configurations possible with this concept and provide additional benefits. One benefit involves making one of modules double-walled haven safe from debris, radiation, and like. Module accessible from either end, and readily available to all positions in space station. Concept also provides flexibility in methods in which Space Shuttle orbiter docked or berthed with space station and decrease chances of damage.

  13. The Ortega Telescope Andor CCD

    NASA Astrophysics Data System (ADS)

    Tucker, M.; Batcheldor, D.

    2012-07-01

    We present a preliminary instrument report for an Andor iKon-L 936 charge-couple device (CCD) being operated at Florida Tech's 0.8 m Ortega Telescope. This camera will replace the current Finger Lakes Instrumentation (FLI) Proline CCD. Details of the custom mount produced for this camera are presented, as is a quantitative and qualitative comparison of the new and old cameras. We find that the Andor camera has 50 times less noise than the FLI, has no significant dark current over 30 seconds, and has a smooth, regular flat field. The Andor camera will provide significantly better sensitivity for direct imaging programs and, once it can be satisfactorily tested on-sky, will become the standard imaging device on the Ortega Telescope.

  14. Workshop on Mars Telescopic Observations

    NASA Technical Reports Server (NTRS)

    Bell, J. F., III (Editor); Moersch, J. E. (Editor)

    1995-01-01

    The Mars Telescopic Observations Workshop, held August 14-15, 1995, at Cornell University in Ithaca, New York, was organized and planned with two primary goals in mind: The first goal was to facilitate discussions among and between amateur and professional observers and to create a workshop environment fostering collaborations and comparisons within the Mars observing community. The second goal was to explore the role of continuing telescopic observations of Mars in the upcoming era of increased spacecraft exploration. The 24 papers presented at the workshop described the current NASA plans for Mars exploration over the next decade, current and recent Mars research being performed by professional astronomers, and current and past Mars observations being performed by amateur observers and observing associations. The workshop was divided into short topical sessions concentrating on programmatic overviews, groundbased support of upcoming spacecraft experiments, atmospheric observations, surface observations, modeling and numerical studies, and contributions from amateur astronomers.

  15. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan P.

    2011-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. It will be a large (6.6m) cold (50K) telescope launched in about 5 years into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and black holes within them evolved from the epoch of reionization to the present. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. I will conclude the talk with a description of recent technical progress in the construction of the observatory.

  16. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan P.

    2011-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. It will be a large (6.6m) cold (50K) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and black holes within them evolved from the epoch of reionization to the present. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. I will conclude the talk with a description of recent technical progress in the construction of the observatory.

  17. Opening the Dutch Open Telescope

    NASA Astrophysics Data System (ADS)

    Rutten, R. J.; de Wijn, A. G.; Sütterlin, P.; Bettonvil, F. C. M.; Hammerschlag, R. H.

    2002-10-01

    We hope to "open the DOT" to the international solar physics community as a facility for high-resolution tomography of the solar atmosphere. Our aim is to do so combining peer-review time allocation with service-mode operation in a "hands-on-telescope" education program bringing students to La Palma to assist in the observing and processing. The largest step needed is considerable speedup of the DOT speckle processing.

  18. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan P.

    2011-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes, and is currently the largest scientific project under construction in the United States. It will be a large (6.6m) cold (50K) telescope launched in about 5 years into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. Science with the James Webb Space Telescope falls into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and black holes within them evolved from the epoch of reionization to the present. The Birth of Stars and Proto planetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. I will conclude the talk with a description of recent technical progress in the construction of the observatory.

  19. Building the Green Bank Telescope

    NASA Astrophysics Data System (ADS)

    Kellermann, Kenneth I.

    2017-01-01

    In a previous presentation, I reported on how the freak collapse of the NRAO 300-ft transit radio telescope led to the inclusion of $75 million for a new radio telescope in the 1989 Congressional Emergency Supplemental Appropriations Act. But, this was only the beginning. NRAO was faced with challenging specifications and an unworkable schedule, but there was no design and no project team. Only one bid was even close to the Congressional appropriation. In an attempt to meet the unrealistic antenna delivery date, the contractor started construction of the foundation and fabrication of antenna members before the design was finished, leading to retrofits, redesign, and multiple delays. The antenna contractor was twice sold to other companies leading to further delays and cost escalation. In order to recoup their mounting losses, the new owners sued NRAO for $29 million for claimed design changes, and NRAO countersued demanding to be reimbursed for added project management costs and lost scientific data resulting from the seven-year delay in the completion of the telescope. Legal fees and a small net award in favor of the contractor left NRAO and the NSF with a nine million dollar bill which NSF handled by an innovative accounting adjustment.

  20. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Nowak, Maria; Eichorn, William; Hill, Michael; Hylan, Jason; Marsh, James; Ohl, Raymond; Sampler, Henry; Wright, Geraldine; Crane, Allen; Herrera, Acey; Quigley, Robert; Jetten, Mark; Young, Philip

    2007-01-01

    The James Webb Space Telescope (JWST) is a 6.6m diameter, segmented, deployable telescope for cryogenic IR space astronomy (approx.40K). The JWST Observatory architecture includes the Optical Telescope Element and the Integrated Science Instrument Module (ISIM) element that contains four science instruments (SI) including a Guider. The ISIM optical metering structure is a roughly 2.2x1.7x2.2mY, asymmetric frame that is composed of carbon fiber and resin tubes bonded to invar end fittings and composite gussets and clips. The structure supports the SIs, isolates the SIs from the OTE, and supports thermal and electrical subsystems. The structure is attached to the OTE structure via strut-like kinematic mounts. The ISM structure must meet its requirements at the approx.40K cryogenic operating temperature. The SIs are aligned to the structure s coordinate system under ambient, clean room conditions using laser tracker and theodolite metrology. The ISM structure is thermally cycled for stress relief and in order to measure temperature-induced mechanical, structural changes. These ambient-to-cryogenic changes in the alignment of SI and OTE-related interfaces are an important component in the JWST Observatory alignment plan and must be verified.

  1. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan P.

    2012-01-01

    The James Webb Space Telescope is the scientific successor to the Hubble and Spitzer Space Telescopes. It will be a large (6.6m) cold (SDK) telescope launched into orbit around the second Earth-Sun Lagrange point. It is a partnership of NASA with the European and Canadian Space Agencies. The science goals for JWST include the formation of the first stars and galaxies in the early universe; the chemical, morphological and dynamical buildup of galaxies and the formation of stars and planetary systems. Recently, the goals have expanded to include studies of dark energy, dark matter, active galactic nuclei, exoplanets and Solar System objects. Webb will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Near-Infrared Imager and Slitless Spectrograph will cover the wavelength range 0.6 to S microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. The observatory is confirmed for launch in 2018; the design is complete and it is in its construction phase. Recent progress includes the completion of the mirrors, the delivery of the first flight instruments and the start of the integration and test phase.

  2. Sensitivity of coded mask telescopes

    SciTech Connect

    Skinner, Gerald K

    2008-05-20

    Simple formulas are often used to estimate the sensitivity of coded mask x-ray or gamma-ray telescopes, but these are strictly applicable only if a number of basic assumptions are met. Complications arise, for example, if a grid structure is used to support the mask elements, if the detector spatial resolution is not good enough to completely resolve all the detail in the shadow of the mask, or if any of a number of other simplifying conditions are not fulfilled. We derive more general expressions for the Poisson-noise-limited sensitivity of astronomical telescopes using the coded mask technique, noting explicitly in what circumstances they are applicable. The emphasis is on using nomenclature and techniques that result in simple and revealing results. Where no convenient expression is available a procedure is given that allows the calculation of the sensitivity. We consider certain aspects of the optimization of the design of a coded mask telescope and show that when the detector spatial resolution and the mask to detector separation are fixed, the best source location accuracy is obtained when the mask elements are equal in size to the detector pixels.

  3. QUIJOTE telescope design and fabrication

    NASA Astrophysics Data System (ADS)

    Gomez, Alberto; Murga, Gaizka; Etxeita, Borja; Sanquirce, Rubén; Rebolo, Rafael; Rubiño-Martin, Jose Alberto; Herreros, José-Miguel; Hoyland, Roger; Gomez, Francisca; Génova-Santos, Ricardo T.; Piccirillo, Lucio; Maffei, Bruno; Watson, Robert

    2010-07-01

    The QUIJOTE CMB experiment aims to characterize the polarization of the CMB in the frequency range 10-30 GHz and large angular scales. It will be installed in the Teide Observatory, following the projects that the Anisotropy of the Cosmic Microwave Background group has developed in the past (Tenerife experiment, IAC-Bartol experiment...) and is running at the present time (VSA, Cosmosomas). The QUIJOTE CMB experiment will consist of two telescopes which will be installed inside a unique enclosure, which is already constructed. The layout of both telescopes is based on an altazimuth mount supporting a primary and a secondary mirror disposed in a offset Gregorian Dragon scheme. The use of industrial-like fabrication techniques, such as sand-mould casting, CNC machining, and laser tracker measuring for alignment, provided the required performances for microwave observation. A fast-track construction scheme, altogether with the use of these fabrication techniques allowed designing and manufacturing the opto-mechanics of the telescope in 14 months prior to delivery for final start-up in December 2008.

  4. EUSO-TA prototype telescope

    NASA Astrophysics Data System (ADS)

    Bisconti, Francesca

    2016-07-01

    EUSO-TA is one of the prototypes developed for the JEM-EUSO project, a space-based large field-of-view telescope to observe the fluorescence light emitted by cosmic ray air showers in the atmosphere. EUSO-TA is a ground-based prototype located at the Telescope Array (TA) site in Utah, USA, where an Electron Light Source and a Central Laser Facility are installed. The purpose of the EUSO-TA project is to calibrate the prototype with the TA fluorescence detector in presence of well-known light sources and cosmic ray air showers. In 2015, the detector started the first measurements and tests using the mentioned light sources have been performed successfully. A first cosmic ray candidate has been observed, as well as stars of different magnitude and color index. Since Silicon Photo-Multipliers (SiPMs) are very promising for fluorescence telescopes of next generation, they are under consideration for the realization of a new prototype of EUSO Photo Detector Module (PDM). The response of this sensor type is under investigation through simulations and laboratory experimentation.

  5. CMB Telescopes and Optical Systems

    NASA Astrophysics Data System (ADS)

    Hanany, Shaul; Niemack, Michael D.; Page, Lyman

    The cosmic microwave background radiation (CMB) is now firmly establishedas a fundamental and essential probe of the geometry, constituents, and birth ofthe observable universe. The CMB is a potent observable because it can bemeasured with precision and accuracy. Just as importantly, theoretical models ofthe universe can predict the characteristics of the CMB to high accuracy, andthose predictions can be directly compared to observations. There are multipleaspects associated with making a precise measurement. In this chapter, we focuson optical components for the instrumentation used to measure the CMBpolarization and temperature anisotropy. We begin with an overview of generalconsiderations for CMB observations and discuss common concepts used inthe community. We next consider a variety of alternatives available for adesigner of a CMB telescope. Our discussion is guided by the ground- andballoon-based instruments that have been implemented over the years. In thesame vein, we compare the arc-minute resolution Atacama CosmologyTelescope (ACT) and the South Pole Telescope (SPT). CMB interferometersare presented briefly. We conclude with a comparison of the four CMBsatellites, Relikt, COBE, WMAP, and Planck, to demonstrate a remarkableevolution in design, sensitivity, resolution, and complexity over the past30 years.

  6. The NASA Spitzer Space Telescope.

    PubMed

    Gehrz, R D; Roellig, T L; Werner, M W; Fazio, G G; Houck, J R; Low, F J; Rieke, G H; Soifer, B T; Levine, D A; Romana, E A

    2007-01-01

    The National Aeronautics and Space Administration's Spitzer Space Telescope (formerly the Space Infrared Telescope Facility) is the fourth and final facility in the Great Observatories Program, joining Hubble Space Telescope (1990), the Compton Gamma-Ray Observatory (1991-2000), and the Chandra X-Ray Observatory (1999). Spitzer, with a sensitivity that is almost three orders of magnitude greater than that of any previous ground-based and space-based infrared observatory, is expected to revolutionize our understanding of the creation of the universe, the formation and evolution of primitive galaxies, the origin of stars and planets, and the chemical evolution of the universe. This review presents a brief overview of the scientific objectives and history of infrared astronomy. We discuss Spitzer's expected role in infrared astronomy for the new millennium. We describe pertinent details of the design, construction, launch, in-orbit checkout, and operations of the observatory and summarize some science highlights from the first two and a half years of Spitzer operations. More information about Spitzer can be found at http://spitzer.caltech.edu/.

  7. Sensitivity of coded mask telescopes.

    PubMed

    Skinner, Gerald K

    2008-05-20

    Simple formulas are often used to estimate the sensitivity of coded mask x-ray or gamma-ray telescopes, but these are strictly applicable only if a number of basic assumptions are met. Complications arise, for example, if a grid structure is used to support the mask elements, if the detector spatial resolution is not good enough to completely resolve all the detail in the shadow of the mask, or if any of a number of other simplifying conditions are not fulfilled. We derive more general expressions for the Poisson-noise-limited sensitivity of astronomical telescopes using the coded mask technique, noting explicitly in what circumstances they are applicable. The emphasis is on using nomenclature and techniques that result in simple and revealing results. Where no convenient expression is available a procedure is given that allows the calculation of the sensitivity. We consider certain aspects of the optimization of the design of a coded mask telescope and show that when the detector spatial resolution and the mask to detector separation are fixed, the best source location accuracy is obtained when the mask elements are equal in size to the detector pixels.

  8. Portable triple silicon detector telescope spectrometer for skin dosimetry

    NASA Astrophysics Data System (ADS)

    Helt-Hansen, J.; Larsen, H. E.; Christensen, P.

    1999-12-01

    The features of a newly developed portable beta telescope spectrometer are described. The detector probe uses three silicon detectors with the thickness: 50μm/150μm/7000μm covered by a 2μm thick titanium window. Rejection of photon contributions from mixed beta/photon exposures is achieved by coincidence requirements between the detector signals. The silicon detectors, together with cooling aggregate, bias supplies, preamplifiers and charge generation for calibration are contained in a handy detector probe. Through a 3- or 10-m cable the detector unit is connected to a compact, portable processing unit including a laptop computer executing control, monitor, histogram and display tasks. The use of digital signal processing at an early stage of the signal chain has facilitated the achievement of a compact, low-weight device. 256 channels are available for each of the three detectors. The LabVIEWTM software distributed by National Instruments was used for all program developments for the spectrometer, comprising also the capability of evaluating the absorbed dose rates from the measured beta spectra. The report describes the capability of the telescope spectrometer to measure beta and photon spectra as well as beta dose rates in mixed beta/photon radiation fields. It also describes the main features of the digital signal-processing electronics.

  9. Equal-Curvature X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    Saha, Timo T.; Zhang, William

    2002-01-01

    We introduce a new type of x-ray telescope design; an Equal-Curvature telescope. We simply add a second order axial sag to the base grazing incidence cone-cone telescope. The radius of curvature of the sag terms is the same on the primary surface and on the secondary surface. The design is optimized so that the on-axis image spot at the focal plane is minimized. The on-axis RMS (root mean square) spot diameter of two studied telescopes is less than 0.2 arc-seconds. The off-axis performance is comparable to equivalent Wolter type 1 telescopes.

  10. Cost Modeling for Space Optical Telescope Assemblies

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Henrichs, Todd; Luedtke, Alexander; West, Miranda

    2011-01-01

    Parametric cost models are used to plan missions, compare concepts and justify technology investments. This paper reviews an on-going effort to develop cost modes for space telescopes. This paper summarizes the methodology used to develop cost models and documents how changes to the database have changed previously published preliminary cost models. While the cost models are evolving, the previously published findings remain valid: it costs less per square meter of collecting aperture to build a large telescope than a small telescope; technology development as a function of time reduces cost; and lower areal density telescopes cost more than more massive telescopes.

  11. Serviceable Large Low Cost/Mass Infrared 4 Kelvin Telescope Passively Cooled

    NASA Astrophysics Data System (ADS)

    Tenerelli, Domenick; Tolomeo, J.; Klavins, A.; Putnam, D.

    2012-05-01

    An innovative space telescope concept was studied for the New Millenium program for ST6. The telescope called a Dual Anamorphic Reflector Telescope (DART) features two single curvature monolith parabolic surfaces. The telescope system personifies simplicity which extrapolates to low cost and mass. We at Lockheed Martin have implemented this design in two large prototypes that demonstrate imaging in the IR without the use of corrective optics as well as demonstrate the mass scaling advantageous of this architecture. A serviceable deployment concept is described which will enable apertures greater than 10m with areal density less than 10 kg/m2 to be realized for space applications. Because of the overall simplicity of the architecture the instrument section is easily replaceable when new detector technology is developed. In addition the simplicity of the overall architecture allows the system to assembled on the International Space Station (ISS). Anti sun pointing, low conductance support structure and deployable sun shade made of multiple deployable shields in an open groove configuration maintains telescope temperatures near 4K with minimal gradients

  12. Metrology System for a Large, Somewhat Flexible Telescope

    NASA Technical Reports Server (NTRS)

    Liebe, Carl Christian; Bartman, Randall; Cook, Walter; Craig, William

    2009-01-01

    A proposed metrology system would be incorporated into a proposed telescope that would include focusing optics on a rigid bench connected via a deployable mast to another rigid bench holding a focal-plane array of photon counting photodetectors. Deformations of the deployable mast would give rise to optical misalignments that would alter the directions (and, hence, locations) of incidence of photons on the focal plane. The metrology system would measure the relative displacement of the focusing- optics bench and the focal-plane array bench. The measurement data would be used in post-processing of the digitized photodetector outputs to compensate for the mast-deformation-induced changes in the locations of incidence of photons on the focal plane, thereby making it possible to determine the original directions of incidence of photons with greater accuracy. The proposed metrology system is designed specifically for the Nuclear Spectroscopic Telescope Array (NuSTAR) a proposed spaceborne x-ray telescope. The basic principles of design and operation are also applicable to other large, somewhat flexible telescopes, both terrestrial and spaceborne. In the NuSTAR, the structural member connecting the optical bench and the photodetector array would be a 10-m-long deployable mast, and there is a requirement to keep errors in measured directions of incidence of photons below 10 arc seconds (3 sigma). The proposed system would include three diode lasers that would be mounted on the focusing-optics bench. For clarity, only one laser is shown in the figure, which is a greatly simplified schematic diagram of the system. Each laser would be aimed at a position-sensitive photodiode that would be mounted on the detector bench alongside the aforementioned telescope photodetector array. The diode lasers would operate at a wavelength of 830 nm, each at a power of 200 mW. Each laser beam would be focused to a spot of .1-mm diameter on the corresponding position-sensitive photodiode. To

  13. Wavefront Analysis of Adaptive Telescope

    NASA Technical Reports Server (NTRS)

    Hadaway, James B.; Hillman, Lloyd

    1997-01-01

    The motivation for this work came from a NASA Headquarters interest in investigating design concepts for a large space telescope employing active optics technology. Current and foreseeable launch vehicles will be limited to carrying around 4-5 meter diameter objects. Thus, if a large, filled-aperture telescope (6-20 meters in diameter) is to be placed in space, it will be required to have a deployable primary mirror. Such a mirror may be an inflatable membrane or a segmented mirror consisting of many smaller pieces. In any case, it is expected that the deployed primary will not be of sufficient quality to achieve diffraction-limited performance for its aperture size. Thus, an active optics system will be needed to correct for initial as well as environmentally-produced primary figure errors. Marshall Space Flight Center has developed considerable expertise in the area of active optics with the PAMELA test-bed. The combination of this experience along with the Marshall optical shop's work in mirror fabrication made MSFC the logical choice to lead NASA's effort to develop active optics technology for large, space-based, astronomical telescopes. Furthermore, UAH's support of MSFC in the areas of optical design, fabrication, and testing of space-based optical systems placed us in a key position to play a major role in the development of this future-generation telescope. A careful study of the active optics components had to be carried out in order to determine control segment size, segment quality, and segment controllability required to achieve diffraction-limited resolution with a given primary mirror. With this in mind, UAH undertook the following effort to provide NASA/MSFC with optical design and analysis support for the large telescope study. All of the work performed under this contract has already been reported, as a team member with MSFC, to NASA Headquarters in a series of presentations given between May and December of 1995. As specified on the delivery

  14. Twin-Telescope Wettzell (TTW)

    NASA Astrophysics Data System (ADS)

    Hase, H.; Dassing, R.; Kronschnabl, G.; Schlüter, W.; Schwarz, W.; Lauber, P.; Kilger, R.

    2007-07-01

    Following the recommendations made by the VLBI2010 vision report of the IVS, a proposal has been made to construct a Twin Telescope for the Fundamental Station Wettzell in order to meet the future requirements of the next VLBI generation. The Twin Telescope consists of two identical radiotelescopes. It is a project of the Federal Agency for Cartography and Geodesy (BKG). This article summarizes the project and some design ideas for the Twin-Telescope. %ZALMA (2005). Technical Specification for Design, Manufacturing, Transport and Integration on Site of the ALMA ANTENNAS, Doc. ALMA-34.00.00.00.006-BSPE. Behrend, D. (2006). VLBI2010 Antenna Specs, Data sheet. DeBoer, D. (2001). The ATA Offset Gregorian Antenna, ATA Memo #16, February 10. Imbriale, W.A. (2006). Design of a Wideband Radio Telescope, Jet Propulsion Laboratory and S. Weinreb and H. Mandi, California Institute of Technology. Kilger, R. (2007). TWIN-Design studies, Presentation for the IVS board members (internal document),Wettzell. Kronschnabl, G. (2006). Subject: Memo from Bill Petrachenko, E-mail to the Twin-Working Group (in German), July. Lindgren, ETS-Lindgren (2005). The Model 3164-05 Open Boundary Quadridge Horn, Data Sheet. Niell, A., A. Whitney, W. Petrachenko, W. Schlüter, N. Vandenberg, H.Hase, Y. Koyama, C. Ma, H. Schuh, G. Tucari (2006). in: IVS Annual Report 2005, pg. 13-40, NASA/TP-2006-214136, April. Olsson, R., Kildal, P.-S., and Weinreb, S. (2006). IEEE Transactions on Antennas and Propagation, Vol. 54, No. 2, February. Petrachenko, B. (2006). The Case For and Against Multiple Antennas at a Site, IVS Memorandum, 2006-019v01. Petrachenko, B. (2006). IVS Memorandum, 2006-016v01. RFSpin (2004). Double Ridged Waveguide Horn-Model DRH20, Antenna Specifications, Data Sheet. Rohde&Schwarz (2004). SHF Antennas Crossed Log- Periodic Antennas HL024A1/S1, Data Sheet. Rohde&Schwarz (2004). SHF Antennas Log-Periodic Antennas HL050/HL050S1, Data Sheet. Rogers, A.E.E. (2006). Simulations of broadband

  15. Aligning Astronomical Telescopes via Identification of Stars

    NASA Technical Reports Server (NTRS)

    Whorton, Mark

    2010-01-01

    A proposed method of automated, precise alignment of a ground-based astronomical telescope would eliminate the need for initial manual alignment. The method, based on automated identification of known stars and other celestial objects in the telescope field of view, would also eliminate the need for an initial estimate of the aiming direction. The method does not require any equipment other than a digital imaging device such as a charge-coupled-device digital imaging camera and control computers of the telescope and camera, all of which are standard components in professional astronomical telescope systems and in high-end amateur astronomical telescope systems. The method could be implemented in software running in the telescope or camera control computer or in an external computer communicating with the telescope pointing mount and camera control computers.

  16. Object-oriented software design for the Mt. Wilson 100-inch Hooker telescope adaptive optics system

    NASA Astrophysics Data System (ADS)

    Schneider, Thomas G.

    2000-06-01

    The object oriented software design paradigm has been instrumented in the development of the Adoptics software used in the Hooker telescope's ADOPT adaptive optics system. The software runs on a Pentium-class PC host and eight DSP processors connected to the host's motherboard bus. C++ classes were created to implement most of the host software's functionality, with the object oriented features of inheritance, encapsulation and abstraction being the most useful. Careful class design at the inception of the project allowed for the rapid addition of features without comprising the integrity of the software. Base class implementations include the DSP system, real-time graphical displays and opto-mechanical actuator control.

  17. Investigation on High Performance of 10m Semi Anechoic Chamber by using Open-Top Hollow Pyramidal Hybrid EM Wave Absorber

    NASA Astrophysics Data System (ADS)

    Kurihara, Hiroshi; Saito, Toshifumi; Suzuki, Yoshikazu; Nishikata, Atsuhiro; Hashimoto, Osamu

    The emission radiated from electric and electronic equipments is evaluated through OATS. Recently, it is not fully prepared the environment for OATS because of a variety of communication radiation sources (e.g., digital television broadcast and cellular phone station). Therefore, the EM anechoic chambers are becoming more and more important as EMI test site. On the other hand, the EM anechoic chambers are needed high performance in order to cut down EMI countermeasure cost and calculate the antenna factor. The objective of this paper is mainly to present the EM wave absorber design in order to obtain within ±2dB against the theoretical site attenuation values in the 10m semi anechoic chamber at 30MHz to 300MHz. We get the necessary reflectivity of EM wave absorber by the basic site attenuation equation. We design the open-top hollow pyramidal new hybrid EM wave absorber consisted of 180cm long dielectric loss foam and ferrite tiles. Then, we design the 10m semi anechoic chamber by using the ray-tracing simulation and construct it in the size of L24m×W15.2m×H11.2m. More over, we measure the site attenuation of the constructed 10m semi anechoic chamber by using the broadband calculable dipole antennas. As the result, we confirm the validity of the designed open-top hollow pyramidal new hybrid EM wave absorber.

  18. Class distinction

    NASA Astrophysics Data System (ADS)

    White, M. Catherine

    Typical 101 courses discourage many students from pursuing higher level science and math courses. Introductory classes in science and math serve largely as a filter, screening out all but the most promising students, and leaving the majority of college graduates—including most prospective teachers—with little understanding of how science works, according to a study conducted for the National Science Foundation. Because few teachers, particularly at the elementary level, experience any collegiate science teaching that stresses skills of inquiry and investigation, they simply never learn to use those methods in their teaching, the report states.

  19. Eastern Anatolia Observatory (DAG): Recent developments and a prospective observing site for robotic telescopes

    NASA Astrophysics Data System (ADS)

    Yesilyaprak, C.; Yerli, S. K.; Keskin, O.

    2016-12-01

    This document (Eastern Anatolia Observatory (DAG) is the new observatory of Turkey with the optical and near-infrared largest telescope (4 m class) and its robust observing site infrastructure. This national project consists of three phases with DAG (Telescope, Enclosure, Buildings and Infrastructures), FPI (Focal Plane Instruments and Adaptive Optics) and MCP (Mirror Coating Plant) and is supported by the Ministry of Development of Turkey. The tenders of telescope and enclosure have been made and almost all the infrastructure (roads, geological and atmospherical surveys, electricity, fiber optics, cable car, water, generator, etc.) of DAG site (Erzurum/Turkey, 3,170 m altitude) have been completed. This poster is about the recent developments of DAG and about the future possible collaborations for various robotic telescopes which can be set up in DAG site.

  20. Extremely large telescope: a twenty-five meter aperture for the twenty-first century

    NASA Astrophysics Data System (ADS)

    Bash, Frank N.; Sebring, Thomas A.; Ray, Frank B.; Ramsey, Lawrence W.

    1997-03-01

    The 10-meter class Hobby-Eberly telescope (HET), now nearing completion, provides technology for optical Arecibo-type telescopes which can be extrapolated to even larger apertures. Utilizing a fixed elevation angle and a spherical segmented primary mirror provides cost effective and pragmatic solutions to mirror mounting and fabrication. Arecibo-type tracking implies a greatly reduced tracking mass and no change to the gravity vector for the primary mirror. Such a telescope can address 70 percent of the available sky and exhibit optical quality easily sufficient for effective spectroscopy and photometry. The extremely large telescope takes advantage of several key engineering approaches demonstrated by the HET project to achieve a cost comparable to similarly-sized radio rather than optical telescopes. These engineering approaches include: bolted pre-manufactured primary mirror truss, factory manufactured geodesic enclosure dome, air bearing rotation of primary mirror, tracker, and dome systems directly on concrete piers, and tracking via a hexapod system. Current estimates put the cost of the ELT at $200 million for a 25-meter aperture utilizing a 33-meter primary mirror array. Construction of the ELT would provide the astronomy community with an optical telescope nearly an order of magnitude larger than even the largest telescopes in operation or under construction today.

  1. The Xinglong 2.16-m Telescope: Current Instruments and Scientific Projects

    NASA Astrophysics Data System (ADS)

    Fan, Zhou; Wang, Huijuan; Jiang, Xiaojun; Wu, Hong; Li, Hongbin; Huang, Yang; Xu, Dawei; Hu, Zhongwen; Zhu, Yinan; Wang, Jianfeng; Komossa, Stefanie; Zhang, Xiaoming

    2016-11-01

    The Xinglong 2.16-m reflector is the first 2-m class astronomical telescope in China. It was jointly designed and built by the Nanjing Astronomical Instruments Factory (NAIF), Beijing Astronomical Observatory (now National Astronomical Observatories, Chinese Academy of Sciences, NAOC), and Institute of Automation, Chinese Academy of Sciences in 1989. It is a Ritchey-Chrétien (R-C) reflector on an English equatorial mount and the effective aperture is 2.16 m. It had been the largest optical telescope in China for ˜18 years until the Guoshoujing Telescope (also called Large Sky Area Multi-Object Fiber Spectroscopic Telescope, LAMOST) and the Lijiang 2.4-m telescope were built. At present, there are three main instruments on the Cassegrain focus available: the Beijing Faint Object Spectrograph and Camera (BFOSC) for direct imaging and low-resolution (R ˜ 500-2000) spectroscopy, the spectrograph made by Optomechanics Research Inc. (OMR) for low-resolution spectroscopy (the spectral resolutions are similar to those of BFOSC) and the fiber-fed High Resolution Spectrograph (HRS; R ˜ 30,000-65,000). The telescope is widely open to astronomers all over China as well as international astronomical observers. Each year there are more than 40 ongoing observing projects, including 6-8 key projects. Recently, some new techniques and instruments (e.g., astro-frequency comb calibration system, polarimeter, and adaptive optics) have been or will be tested on the telescope to extend its observing abilities.

  2. The Northwest Indiana Robotic Telescope

    NASA Astrophysics Data System (ADS)

    Slavin, Shawn D.; Rengstorf, A. W.; Aros, J. C.; Segally, W. B.

    2011-01-01

    The Northwest Indiana Robotic (NIRo) Telescope is a remote, automated observing facility recently built by Purdue University Calumet (PUC) at a site in Lowell, IN, approximately 30 miles from the PUC campus. The recently dedicated observatory will be used for broadband and narrowband optical observations by PUC students and faculty, as well as pre-college students through the implementation of standards-based, middle-school modules developed by PUC astronomers and education faculty. The NIRo observatory and its web portal are the central technical elements of a project to improve astronomy education at Purdue Calumet and, more broadly, to improve science education in middle schools of the surrounding region. The NIRo Telescope is a 0.5-meter (20-inch) Ritchey-Chrétien design on a Paramount ME robotic mount, featuring a seven-position filter wheel (UBVRI, Hα, Clear), Peltier (thermoelectrically) cooled CCD camera with 3056 x 3056, square, 12 μm pixels, and off-axis guiding. It provides a coma-free imaging field of 0.5 degrees square, with a plate scale of 0.6 arcseconds per pixel. The observatory has a wireless internet connection, local weather station which publishes data to an internet weather site, and a suite of CCTV security cameras on an IP-based, networked video server. Control of power to every piece of instrumentation is maintained via internet-accessible power distribution units. The telescope can be controlled on-site, or off-site in an attended fashion via an internet connection, but will be used primarily in an unattended mode of automated observation, where queued observations will be scheduled daily from a database of requests. Completed observational data from queued operation will be stored on a campus-based server, which also runs the web portal and observation database. Partial support for this work was provided by the National Science Foundation's Course, Curriculum, and Laboratory Improvement (CCLI) program under Award No. 0736592.

  3. The James Webb Space Telescope

    NASA Technical Reports Server (NTRS)

    Gardner, Jonathan P.

    2007-01-01

    The scientific capabilities of the James Webb Space Telescope (JWST) fall into four themes. The End of the Dark Ages: First Light and Reionization theme seeks to identify the first luminous sources to form and to determine the ionization history of the universe. The Assembly of Galaxies theme seeks to determine how galaxies and the dark matter, gas, stars, metals, morphological structures, and active nuclei within them evolved from the epoch of reionization to the present. The Birth of Stars and Protoplanetary Systems theme seeks to unravel the birth and early evolution of stars, from infall onto dust-enshrouded protostars, to the genesis of planetary systems. The Planetary Systems and the Origins of Life theme seeks to determine the physical and chemical properties of planetary systems around nearby stars and of our own, and investigate the potential for life in those systems. To enable these four science themes, JWST will be a large (6.6m) cold (50K) telescope launched to the second Earth-Sun Lagrange point early in the next decade. It is the successor to the Hubble Space Telescope, and is a partnership of NASA, ESA and CSA. JWST will have four instruments: The Near-Infrared Camera, the Near-Infrared multi-object Spectrograph, and the Tunable Filter Imager will cover the wavelength range 0.6 to 5 microns, while the Mid-Infrared Instrument will do both imaging and spectroscopy from 5 to 28.5 microns. In this paper, the status and capabilities of the observatory and instruments in the context of the major scientific goals are reviewed.

  4. Hubble Space Telescope battery background

    NASA Technical Reports Server (NTRS)

    Standlee, Dan

    1991-01-01

    The following topics are presented in viewgraph form and include the following: the MSFC Hubble Space Telescope (HST) Nickel-Hydrogen Battery Contract; HST battery design requirements; HST nickel-hydrogen battery development; HST nickel-hydrogen battery module; HST NiH2 battery module hardware; pressure vessel design; HST NiH2 cell design; offset non-opposing vs. rabbit ear cell; HST NiH2 specified capacity; HST NiH2 battery design; and HST NiH2 module design.

  5. Revealing the Hidden Wave: Using the Very Small Radio Telescope to Teach High School Physics

    ERIC Educational Resources Information Center

    Doherty, Michael; Fish, Vincent L.; Needles, Madeleine

    2011-01-01

    Scientists and teachers have worked together to produce teaching materials for the Very Small Radio Telescope (VSRT), an easy-to-use, low-cost apparatus that can be used in multiple laboratory experiments in high school and university physics and astronomy classes. In this article, we describe the motivation for the VSRT and several of the…

  6. Large aperture diffractive space telescope

    DOEpatents

    Hyde, Roderick A.

    2001-01-01

    A large (10's of meters) aperture space telescope including two separate spacecraft--an optical primary objective lens functioning as a magnifying glass and an optical secondary functioning as an eyepiece. The spacecraft are spaced up to several kilometers apart with the eyepiece directly behind the magnifying glass "aiming" at an intended target with their relative orientation determining the optical axis of the telescope and hence the targets being observed. The objective lens includes a very large-aperture, very-thin-membrane, diffractive lens, e.g., a Fresnel lens, which intercepts incoming light over its full aperture and focuses it towards the eyepiece. The eyepiece has a much smaller, meter-scale aperture and is designed to move along the focal surface of the objective lens, gathering up the incoming light and converting it to high quality images. The positions of the two space craft are controlled both to maintain a good optical focus and to point at desired targets which may be either earth bound or celestial.

  7. TMT telescope structure thermal model

    NASA Astrophysics Data System (ADS)

    Vogiatzis, Konstantinos; Sadjadpour, Amir; Roberts, Scott

    2014-08-01

    The thermal behavior of the Thirty Meter Telescope (TMT) Telescope Structure (STR) and the STR mounted subsystems depends on the heat load of the System, the thermal properties of component materials and the environment as well as their interactions through convection, conduction and radiation. In this paper the thermal environment is described and the latest three-dimensional Computational Solid Dynamics (CSD) model is presented. The model tracks the diurnal temperature variation of the STR and the corresponding deformations. The resulting displacements are fed into the TMT Merit Function Routine (MFR), which converts them into translations and rotations of the optical surfaces. They, in turn, are multiplied by the TMT optical sensitivity matrix that delivers the corresponding pointing error. Thus the thermal performance of the structure can be assessed for requirement compliance, thermal drift correction strategies and look-up tables can be developed and design guidance can be provided. Results for a representative diurnal cycle based on measured temperature data from the TMT site on Mauna Kea and CFD simulations are presented and conclusions are drawn.

  8. Far Ultraviolot Space Telescope (FAUST)

    NASA Technical Reports Server (NTRS)

    Bowyer, S.

    1988-01-01

    The Far Ultraviolet Space Telescope is a compact, wide field-of-view, far ultraviolet instrument designed for observations of extended and point sources of astronomical interest. It was originally used in sounding rocket work by both French and American investigators. The instrument was modified for flight on the space shuttle and flew on the Spacelab 1 mission as a joint effort between the Laboratoire d'Astronomie Spatiale and the University of California, Berkeley. The prime experiment objective of this telescope on the Atmospheric Laboratory Applications and Science (ATLAS 1) NASA mission is to observe faint astronomical sources in the far ultraviolet with sensitivities far higher than previously available. The experiment will cover the 1300 to 1800 A band, which is inaccessible to observers on earth. The observing program during the mission consists of obtaining deep sky images during spacecraft nighttime. The targets will include hot stars and nebulae in our own galaxy, faint diffuse galactic features similar to the cirrus clouds seen by the Infrared Astronomical Satellite (IRAS), large nearby galaxies, nearby clusters of galaxies, and objects of cosmological interest such as quasars and the diffuse far ultraviolet background.

  9. Origins Space Telescope: Community Participation

    NASA Astrophysics Data System (ADS)

    Carey, Sean J.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its imagers and spectrographs will enable a variety of surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. This poster will outline the ways in which the astronomical community can participate in the STDT activities and a summary of tools that are currently available or are planned for the community during the study. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu.

  10. Space Telescopes and Orbital Debris

    NASA Astrophysics Data System (ADS)

    Seitzer, Patrick

    2009-01-01

    Almost 12,000 artificial objects orbiting the Earth are currently in the public catalog of orbital elements maintained by the USAF. Only a small fraction of them are operational satellites. The remainder is satellites whose missions have ended, rocket bodies, and parts and debris from larger parent objects. And the catalog only contains the biggest and brightest of the objects in orbit. The Low Earth Orbit (LEO) regime where most of this population concentrates is also a regime of incredible interest to astronomers, since it is where flagship missions such as the Hubble Space Telescope and other Great Observatories operate. I'll review the current state of knowledge of the orbital debris population, how it has grown with time, and how this environment could affect current and future space telescopes. There are mitigation measures which many spacecraft operators have adopted which can control the growth of the debris population. Orbital debris research at the University of Michigan is funded by NASA's Orbital Debris Program Office, Johnson Space Center, Houston, Texas.

  11. Mars Telescopic Observations Workshop II

    NASA Technical Reports Server (NTRS)

    Sprague, A. L. (Editor); Bell, J. F., III (Editor)

    1997-01-01

    Mars Telescopic Observations Workshop E convened in Tucson, Arizona, in October 1997 by popular demand slightly over two years following the first successful Mars Telescopic Observations Workshop, held in Ithaca, New York, in August 1995. Experts on Mars from the United Kingdom, Japan, Germany, and the United States were present. Twenty-eight oral presentations were made and generous time allotted for useful discussions among participants. The goals of the workshop were to (1) summarize active groundbased observing programs and evaluate them in the context of current and future space missions to Mars, (2) discuss new technologies and instrumentation in the context of changing emphasis of observations and theory useful for groundbased observing, and (3) more fully understand capabilities of current and planned Mars missions to better judge which groundbased observations are and will continue to be of importance to our overall Mars program. In addition, the exciting new discoveries presented from the Pathfinder experiments and the progress report from the Mars Global Surveyor infused the participants with satisfaction for the successes achieved in the early stages of these missions. Just as exciting was the enthusiasm for new groundbased programs designed to address new challenges resulting from mission science results. We would like to thank the National Aeronautics and Space Administration as well as Dr. David Black, director of the Lunar and Planetary Institute, and the staff of the Institute's Publications and Program Services Department for providing logistical, administrative, and publication support services for this workshop.

  12. Origins Space Telescope: Study Plan

    NASA Astrophysics Data System (ADS)

    Cooray, Asantha R.; Origins Space Telescope Study Team

    2017-01-01

    The Origins Space Telescope (OST) is the mission concept for the Far-Infrared Surveyor, a study in development by NASA in preparation for the 2020 Astronomy and Astrophysics Decadal Survey. Origins is planned to be a large aperture, actively-cooled telescope covering a wide span of the mid- to far-infrared spectrum. Its spectrographs will enable 3D surveys of the sky that will discover and characterize the most distant galaxies, Milky-Way, exoplanets, and the outer reaches of our Solar system. Origins will enable flagship-quality general observing programs led by the astronomical community in the 2030s. The Science and Technology Definition Team (STDT) would like to hear your science needs and ideas for this mission. The team can be contacted at firsurveyor_info@lists.ipac.caltech.edu. This presentation will provide a summary of the OST STDT, the OST Study Team based at NASA Goddard Space Flight Center, study partners, and the advisory panel to the study. This presentation will also summarize recent activities, including the process used to reach a decision on the mission architecture, the identification of key science drivers, and the key study milestones between 2017 and 2020.

  13. JWST Telescope Integration and Test Progress

    NASA Technical Reports Server (NTRS)

    Matthews, Gary W.; Whitman, Tony L.; Feinberg, Lee D.; Voyton, Mark F.; Lander, Juli A.; Keski-Kuha, Ritva

    2016-01-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. The JWST Optical Telescope Element (Telescope) integration and test program is well underway. The telescope was completed in the spring of 2016 and the cryogenic test equipment has been through two optical test programs leading up to the final flight verification program. The details of the telescope mirror integration will be provided along with the current status of the flight observatory. In addition, the results of the two optical ground support equipment cryo tests will be shown and how these plans fold into the flight verification program.

  14. JWST telescope integration and test progress

    NASA Astrophysics Data System (ADS)

    Matthews, Gary W.; Whitman, Tony L.; Feinberg, Lee D.; Voyton, Mark F.; Lander, Juli A.; Keski-Kuha, Ritva

    2016-07-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. The JWST Optical Telescope Element (Telescope) integration and test program is well underway. The telescope was completed in the spring of 2016 and the cryogenic test equipment has been through two optical test programs leading up to the final flight verification program. The details of the telescope mirror integration will be provided along with the current status of the flight observatory. In addition, the results of the two optical ground support equipment cryo tests will be shown and how these plans fold into the flight verification program.

  15. JWST telescope integration and test status

    NASA Astrophysics Data System (ADS)

    Matthews, Gary; Scorse, Thomas; Kennard, Scott; Spina, John; Whitman, Tony; Texter, Scott; Atkinson, Charles; Young, Greg; Keski-Kuha, Ritva; Marsh, James; Lander, Juli; Feinberg, Lee

    2014-08-01

    The James Webb Space Telescope (JWST) is a 6.5m, segmented, IR telescope that will explore the first light of the universe after the big bang. 2014 is an incredible year for the Telescope Alignment, Integration, and Test portion of the program. Long awaited and planned, the two segment Pathfinder telescope will be built and the Optical Ground Support Equipment (OGSE) will be integrated into the large cryo-vacuum chamber at the Johnson Spaceflight Center. The current status of the integration equipment and the demonstrations leading up to the flight-like Pathfinder telescope will be provided as the first step to the final verification of the complex cryo test equipment. The plans and status of bringing the OGSE on-line and ready for a series of risk reduction cryo tests starting in 2015 on the Pathfinder Telescope will also be presented.

  16. Optical aperture synthesis with electronically connected telescopes.

    PubMed

    Dravins, Dainis; Lagadec, Tiphaine; Nuñez, Paul D

    2015-04-16

    Highest resolution imaging in astronomy is achieved by interferometry, connecting telescopes over increasingly longer distances and at successively shorter wavelengths. Here, we present the first diffraction-limited images in visual light, produced by an array of independent optical telescopes, connected electronically only, with no optical links between them. With an array of small telescopes, second-order optical coherence of the sources is measured through intensity interferometry over 180 baselines between pairs of telescopes, and two-dimensional images reconstructed. The technique aims at diffraction-limited optical aperture synthesis over kilometre-long baselines to reach resolutions showing details on stellar surfaces and perhaps even the silhouettes of transiting exoplanets. Intensity interferometry circumvents problems of atmospheric turbulence that constrain ordinary interferometry. Since the electronic signal can be copied, many baselines can be built up between dispersed telescopes, and over long distances. Using arrays of air Cherenkov telescopes, this should enable the optical equivalent of interferometric arrays currently operating at radio wavelengths.

  17. Concept for a Large Space Telescope for Detailed Spectroscopy of Terrestrial exo-planets

    NASA Astrophysics Data System (ADS)

    Angel, J. R. P.; Woolf, N. J.; Burge, J. H.

    1998-12-01

    Once terrestrial planets of other stars are detected, cryogenic space telescopes of large collecting area will be needed to obtain detailed atmospheric spectra in the thermal infrared. Our concept is for an ultralightweight telescope with area approaching 1000 m(2) , made from large flat panels of stretched plastic membrane. Thin reflective material held in tension from points around a plane perimeter is fundamentally stable; its flat shape is not critically dependent on tension, and will hold even against penetration by micrometeorites. The perimeter support points would be actively controlled to maintain their co-planarity. We envisage about ten panels each about 10 m square, arranged on a rigid carbon composite truss to approximate a 100 m x 10 m mirror with 1 km focal length. A separate free-flyer at the quasi-focus would complete the telescope. Where all the beams from the target star overlap, a 10 m concave secondary would be used to form an image of the primary array at about 1/10 scale, and slightly below the plane of incoming beams. At each panel image would be a 1 m tertiary, suitably shaped so as to recollimate each individual starlight beam, or to bring all the beams to a common focus. From this point on the instrument might use the focus directly, or multi-aperture interferometric nulling techniques as described by Angel and Woolf. The unaberrated field will be large enough for exoplanet studies. The new technology goes beyond that needed for an 8 m NGST in two main ways: 1) need for thin metallized plastic of large size and uniform thickness and 2) capability to assemble or deploy in space the structure to support the panels.

  18. Compliant Baffle for Large Telescope Daylight Imaging

    DTIC Science & Technology

    2014-09-01

    Compliant Baffle for Large Telescope Daylight Imaging Steven Griffin, Andrew Whiting, Shawn Haar The Boeing Company Stacie Williams Air Force...not impact wind loading induced jitter on the 3.6 m telescope . Analysis was performed to design a compliant baffle out of a synthetic fabric that...will be a comparison of angular rate sensors and accelerometers mounted on the telescope . 1.0 INTRODUCTION Unsteady wind loading is the largest

  19. Telescope Systems for Balloon-Borne Research

    NASA Technical Reports Server (NTRS)

    Swift, C. (Editor); Witteborn, F. C. (Editor); Shipley, A. (Editor)

    1974-01-01

    The proceedings of a conference on the use of balloons for scientific research are presented. The subjects discussed include the following: (1) astronomical observations with balloon-borne telescopes, (2) orientable, stabilized balloon-borne gondola for around-the-world flights, (3) ultraviolet stellar spectrophotometry from a balloon platform, (4) infrared telescope for balloon-borne infrared astronomy, and (5) stabilization, pointing, and command control of balloon-borne telescopes.

  20. Segmented Mirror Telescope Model and Simulation

    DTIC Science & Technology

    2011-06-01

    NAVAL POSTGRADUATE SCHOOL MONTEREY, CALIFORNIA THESIS SEGMENTED MIRROR TELESCOPE MODEL AND SIMULATION by Travis W. Axtell June 2011 Thesis Co...Mirror Telescope Model and Simulation Travis W. Axtell Naval Postgraduate School Monterey, CA 93943 Department of the Navy Approved for public release...Department of Defense or the U.S. Government. IRB Protocol Number: N/A The Segmented Mirror Telescope (SMT) housed at the Naval Postgraduate School is a

  1. ANTARES: The first undersea neutrino telescope

    NASA Astrophysics Data System (ADS)

    Ageron, M.; Aguilar, J. A.; Al Samarai, I.; Albert, A.; Ameli, F.; André, M.; Anghinolfi, M.; Anton, G.; Anvar, S.; Ardid, M.; Arnaud, K.; Aslanides, E.; Assis Jesus, A. C.; Astraatmadja, T.; Aubert, J.-J.; Auer, R.; Barbarito, E.; Baret, B.; Basa, S.; Bazzotti, M.; Becherini, Y.; Beltramelli, J.; Bersani, A.; Bertin, V.; Beurthey, S.; Biagi, S.; Bigongiari, C.; Billault, M.; Blaes, R.; Bogazzi, C.; de Botton, N.; Bou-Cabo, M.; Boudahef, B.; Bouwhuis, M. C.; Brown, A. M.; Brunner, J.; Busto, J.; Caillat, L.; Calzas, A.; Camarena, F.; Capone, A.; Caponetto, L.; Cârloganu, C.; Carminati, G.; Carmona, E.; Carr, J.; Carton, P. H.; Cassano, B.; Castorina, E.; Cecchini, S.; Ceres, A.; Chaleil, Th.; Charvis, Ph.; Chauchot, P.; Chiarusi, T.; Circella, M.; Compère, C.; Coniglione, R.; Coppolani, X.; Cosquer, A.; Costantini, H.; Cottini, N.; Coyle, P.; Cuneo, S.; Curtil, C.; D'Amato, C.; Damy, G.; van Dantzig, R.; de Bonis, G.; Decock, G.; Decowski, M. P.; Dekeyser, I.; Delagnes, E.; Desages-Ardellier, F.; Deschamps, A.; Destelle, J.-J.; di Maria, F.; Dinkespiler, B.; Distefano, C.; Dominique, J.-L.; Donzaud, C.; Dornic, D.; Dorosti, Q.; Drogou, J.-F.; Drouhin, D.; Druillole, F.; Durand, D.; Durand, R.; Eberl, T.; Emanuele, U.; Engelen, J. J.; Ernenwein, J.-P.; Escoffier, S.; Falchini, E.; Favard, S.; Fehr, F.; Feinstein, F.; Ferri, M.; Ferry, S.; Fiorello, C.; Flaminio, V.; Folger, F.; Fritsch, U.; Fuda, J.-L.; Galatá, S.; Galeotti, S.; Gay, P.; Gensolen, F.; Giacomelli, G.; Gojak, C.; Gómez-González, J. P.; Goret, Ph.; Graf, K.; Guillard, G.; Halladjian, G.; Hallewell, G.; van Haren, H.; Hartmann, B.; Heijboer, A. J.; Heine, E.; Hello, Y.; Henry, S.; Hernández-Rey, J. J.; Herold, B.; Hößl, J.; Hogenbirk, J.; Hsu, C. C.; Hubbard, J. R.; Jaquet, M.; Jaspers, M.; de Jong, M.; Jourde, D.; Kadler, M.; Kalantar-Nayestanaki, N.; Kalekin, O.; Kappes, A.; Karg, T.; Karkar, S.; Karolak, M.; Katz, U.; Keller, P.; Kestener, P.; Kok, E.; Kok, H.; Kooijman, P.; Kopper, C.; Kouchner, A.; Kretschmer, W.; Kruijer, A.; Kuch, S.; Kulikovskiy, V.; Lachartre, D.; Lafoux, H.; Lagier, P.; Lahmann, R.; Lahonde-Hamdoun, C.; Lamare, P.; Lambard, G.; Languillat, J.-C.; Larosa, G.; Lavalle, J.; Le Guen, Y.; Le Provost, H.; Levansuu, A.; Lefèvre, D.; Legou, T.; Lelaizant, G.; Lévéque, C.; Lim, G.; Lo Presti, D.; Loehner, H.; Loucatos, S.; Louis, F.; Lucarelli, F.; Lyashuk, V.; Magnier, P.; Mangano, S.; Marcel, A.; Marcelin, M.; Margiotta, A.; Martinez-Mora, J. A.; Masullo, R.; Mazéas, F.; Mazure, A.; Meli, A.; Melissas, M.; Migneco, E.; Mongelli, M.; Montaruli, T.; Morganti, M.; Moscoso, L.; Motz, H.; Musumeci, M.; Naumann, C.; Naumann-Godo, M.; Neff, M.; Niess, V.; Nooren, G. J. L.; Oberski, J. E. J.; Olivetto, C.; Palanque-Delabrouille, N.; Palioselitis, D.; Papaleo, R.; Păvălaş, G. E.; Payet, K.; Payre, P.; Peek, H.; Petrovic, J.; Piattelli, P.; Picot-Clemente, N.; Picq, C.; Piret, Y.; Poinsignon, J.; Popa, V.; Pradier, T.; Presani, E.; Prono, G.; Racca, C.; Raia, G.; van Randwijk, J.; Real, D.; Reed, C.; Réthoré, F.; Rewiersma, P.; Riccobene, G.; Richardt, C.; Richter, R.; Ricol, J. S.; Rigaud, V.; Roca, V.; Roensch, K.; Rolin, J.-F.; Rostovtsev, A.; Rottura, A.; Roux, J.; Rujoiu, M.; Ruppi, M.; Russo, G. V.; Salesa, F.; Salomon, K.; Sapienza, P.; Schmitt, F.; Schöck, F.; Schuller, J.-P.; Schüssler, F.; Sciliberto, D.; Shanidze, R.; Shirokov, E.; Simeone, F.; Sottoriva, A.; Spies, A.; Spona, T.; Spurio, M.; Steijger, J. J. M.; Stolarczyk, Th.; Streeb, K.; Sulak, L.; Taiuti, M.; Tamburini, C.; Tao, C.; Tasca, L.; Terreni, G.; Tezier, D.; Toscano, S.; Urbano, F.; Valdy, P.; Vallage, B.; van Elewyck, V.; Vannoni, G.; Vecchi, M.; Venekamp, G.; Verlaat, B.; Vernin, P.; Virique, E.; de Vries, G.; van Wijk, R.; Wijnker, G.; Wobbe, G.; de Wolf, E.; Yakovenko, Y.; Yepes, H.; Zaborov, D.; Zaccone, H.; Zornoza, J. D.; Zúñiga, J.

    2011-11-01

    The ANTARES Neutrino Telescope was completed in May 2008 and is the first operational Neutrino Telescope in the Mediterranean Sea. The main purpose of the detector is to perform neutrino astronomy and the apparatus also offers facilities for marine and Earth sciences. This paper describes the design, the construction and the installation of the telescope in the deep sea, offshore from Toulon in France. An illustration of the detector performance is given.

  2. The Advanced Patricle-astrophysics Telescope (APT) Mission Concept

    NASA Astrophysics Data System (ADS)

    Buckley, James

    2017-01-01

    The Advanced Pair Telescope (APT) is a concept for a probe-class gamma-ray mission aimed at two primary science objects: (1) providing sensitivity to thermal-WIMP dark matter over the entire natural range of annihilation cross-sections and masses and (2) identifying short GRBs or gravity wave sources by detecting and localizing MeV gamma-ray transients. The instrument combines a pair tracker and Compton telescope in one simple monolithic design. By using scintillating fibers for the tracker and wavelength-shifting fibers to readout CsI detectors, the instrument could achieve an order of magnitude improvement in sensitivity compared with Fermi at GeV energies, and several orders of magnitude improvement in MeV sensitivity compared to Comptel. The instrument would have roughly the same number of electronic channels as Fermi, but would provide an effective area of 12m2, and a geometry factor of 100 m2 str. The same CsI detectors used in the tracker/Compton telescope could be used for detection of high-energy transition radiation for measurements of light cosmic-ray abundances, making this a multi-purpose astro-particle physics observatory. The instantaneous all-sky sensitivity would provide a capability almost unique over the entire electromagnetic spectrum, providing a critical component of multi-messenger studies of the universe. We acknowledge support from the Washington University McDonnell Center for the Space Sciences.

  3. Design and construction of the Discovery Channel Telescope enclosure

    NASA Astrophysics Data System (ADS)

    Marshall, Heather K.; Teran, Jose U.; Bond, Kevin

    2010-07-01

    The Discovery Channel Telescope (DCT) is a project of Lowell Observatory, undertaken with support from Discovery Communications, Inc., to design and construct a 4-meter class telescope and support facility on a site approximately 40 miles southeast of Flagstaff, Arizona. The Discovery Channel Telescope Enclosure was completed in November, 2009. The DCT Enclosure is an octagonal steel structure with insulated composite panel skin. The structure rotates on sixteen compliant bogie assemblies attached to the stationary facility. The shutter is composed of two independently actuated, bi-parting structures that provide a viewing aperture. To improve seeing, the skin is covered with adhesive aluminum foil tape and the enclosed observing area is passively ventilated via rollup doors. The observing area can also be actively ventilated using a downdraft fan, and there are provisions for upgrades to active air conditioning. The enclosure also includes operational equipment such as a bridge crane, personnel lift, and access platforms. This paper discusses some of the design trades as well as the construction challenges and lessons learned by the DCT Project, its designer M3 Engineering and Technology Corporation (M3), and its general contractor, Building and Engineering Contractors, Southwest (BEC Southwest).

  4. DNA synthesis and microtubule assembly-related events in fertilized Paracentrotus lividus eggs: reversible inhibition by 10 mM procaine.

    PubMed

    Raymond, M N; Foucault, G; Coffe, G; Pudles, J

    1986-04-01

    This report describes the effects of 10 mM procaine on microtubule assembly and on DNA synthesis, as followed by [3H]colchicine binding assays and [3H]thymidine incorporation respectively, in fertilized Paracentrotus lividus eggs. In the absence of microtubule assembly inhibitors, about 25% of the total egg tubulin is submitted to two cycles of polymerization prior to the first cell division, this polymerization process precedes DNA synthesis. If the zygotes are treated with 10 mM procaine in the course of the cell cycle, tubulin polymerization is inhibited or microtubules are disassembled. DNA synthesis is inhibited when procaine treatment is performed 10 min, before the initiation of the S-period. However, when the drug is applied in the course of this synthetic period, the process is normally accomplished, but the next S-period becomes inhibited. Moreover, procaine treatment increases the cytoplasmic pH of the fertilized eggs by about 0.6 to 0.8 pH units. This pH increase precedes microtubule disassembly and inhibition of DNA synthesis. Washing out the drug induces a decrease of the intracellular pH which returns to about the same value as that of the fertilized egg controls. This pH change is then followed by the reinitiation of microtubule assembly, DNA synthesis and cell division. Our results show that the inhibition of both tubulin polymerization and DNA synthesis in fertilized eggs treated with 10 mM procaine, appears to be related to the drug-induced increase in cytoplasmic pH.

  5. Absence of ocular effects after either single or repeated exposure to 10 mW/cm(2) from a 60 GHz CW source.

    PubMed

    Kues, H A; D'Anna, S A; Osiander, R; Green, W R; Monahan, J C

    1999-12-01

    This study was designed to examine ocular effects associated with exposure to millimeter waves (60 GHz). Rabbits served as the primary experimental subjects. To confirm the results of the rabbit experiments in a higher species, the second phase of the study used nonhuman primates (Macaca mulatta). First, this study used time-resolved infrared radiometry to assess the field distribution patterns produced by different antennas operating at 60 GHz. These results allowed us to select an antenna that produced a uniform energy distribution and the best distance at which to expose our experimental subjects. The study then examined ocular changes after exposure at an incident power density of 10 mW/cm(2). Acute exposure of both rabbits and nonhuman primates consisted of a single 8 h exposure, and the repeated exposure protocol consisted of five separate 4 h exposures on consecutive days. One eye in each animal was exposed and the contralateral eye served as the sham-exposed control. After postexposure diagnostic examinations, animals were euthanized and the eyes were removed. Ocular tissue was examined by both light and transmission electron microscopy. Neither microscopic examinations nor the diagnostic procedures performed on the eyes of acute and repeatedly exposed rabbits found any ocular changes that could be attributed to millimeter-wave exposure at 10 mW/cm(2). Examination of the primates after comparable exposures also failed to detect any ocular changes due to exposure. On the basis of our results, we conclude that single or repeated exposure to 60 GHz CW radiation at 10 mW/cm(2) does not result in any detectable ocular damage.

  6. Preliminary Cost Model for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Prince, F. Andrew; Smart, Christian; Stephens, Kyle; Henrichs, Todd

    2009-01-01

    Parametric cost models are routinely used to plan missions, compare concepts and justify technology investments. However, great care is required. Some space telescope cost models, such as those based only on mass, lack sufficient detail to support such analysis and may lead to inaccurate conclusions. Similarly, using ground based telescope models which include the dome cost will also lead to inaccurate conclusions. This paper reviews current and historical models. Then, based on data from 22 different NASA space telescopes, this paper tests those models and presents preliminary analysis of single and multi-variable space telescope cost models.

  7. Robotic telescope observing with the BAA

    NASA Astrophysics Data System (ADS)

    Meadows, P.

    2010-06-01

    Have you ever wished you had access to a telescope that can image down to magnitude 20 from the comfort of your own home? This is now made possible by using the growing number of robotic telescopes around the world that are available for amateur astronomers to acquire such CCD imagery. In 2008, using income derived from the legacy of renowned BAA observer Harold Ridley, the Robotic Telescope Project was started to encourage members to contribute to the various BAA Observing Sections using robotic telescopes, by providing a 50% subsidy on commercial rates (up to a limit per member).

  8. The Dutch Open Telescope on La Palma

    NASA Astrophysics Data System (ADS)

    Rutten, R. J.; Bettonvil, F. C. M.; Hammerschlag, R. H.; Jägers, A. P. L.; Leenaarts, J.; Snik, F.; Sütterlin, P.; Tziotziou, K.; de Wijn, A. G.

    The Dutch Open Telescope (DOT) on La Palma is an innovative solar telescope combining open telescope structure and an open support tower with a multi-wavelength imaging assembly and with synchronous speckle cameras to generate high-resolution movies which sample different layers of the solar atmosphere simultaneously and co-spatially at high resolution over long durations. The DOT test and development phase is nearly concluded. The installation of an advanced speckle processor enables full science utilization including "Open-DOT" time allocation to the international community. Co-pointing with spectropolarimeters at other Canary Island telescopes and with TRACE furnishes valuable Solar-B precursor capabilities.

  9. A New 800 mm Automatic Telescope

    NASA Astrophysics Data System (ADS)

    Andrievsky, S. M.; Molotov, I. E.; Fashchevsky, N. N.; Podlesnyak, S. V.; Zhukov, V. V.; Kouprianov, V. V.; Kashuba, S. G.; Kashuba, V. I.; Mel'nichenko, V. F.; Gorbanev, Yu. M.

    A new automatic telescope, a 800-millimeter main mirror catadioptric anastigmatic aplanat, was constructed by specialists of Odessa National University Astronomical observatory (Ukraine) in cooperation with their colleagues from the ISON project (Russia), and was recently put into operation. The telescope is mounted at Mayaki station in suburb of Odessa. It is equipped with a focal corrector and a professional CCD camera. The telescope is used now for observations of geostationary objects, asteroids, and comets. In addition, this telescope can be used for the high precision photometric observations of faint objects up to 20m.

  10. Developing a Telescope Simulator Towards a Global Autonomous Robotic Telescope Network

    NASA Astrophysics Data System (ADS)

    Giakoumidis, N.; Ioannou, Z.; Dong, H.; Mavridis, N.

    2013-05-01

    A robotic telescope network is a system that integrates a number of telescopes to observe a variety of astronomical targets without being operated by a human. This system autonomously selects and observes targets in accordance to an optimized target. It dynamically allocates telescope resources depending on the observation requests, specifications of the telescopes, target visibility, meteorological conditions, daylight, location restrictions and availability and many other factors. In this paper, we introduce a telescope simulator, which can control a telescope to a desired position in order to observe a specific object. The system includes a Client Module, a Server Module, and a Dynamic Scheduler module. We make use and integrate a number of open source software to simulate the movement of a robotic telescope, the telescope characteristics, the observational data and weather conditions in order to test and optimize our system.

  11. Deep Mapping Observations of the Galactic Circumnuclear Disk with Two Single-dish Telescopes

    NASA Astrophysics Data System (ADS)

    Takekawa, S.; Oka, T.; Tanaka, K.

    2015-12-01

    The circumnuclear disk (CND) is a potential reservoir for material accreting into the central parsec of our Galaxy. Two giant molecular clouds (GMCs; +20 km s-1 and +50 km s-1 clouds) are adjacent to the CND. Although several authors have suggested the physical connection between these GMCs and the CND, no compelling evidence of physical connections has been found to date. Recently we have performed deep OTF mapping observations of the CND with the NRO 45 m radio telescope and the ASTE 10 m telescope in the HCN J=1-0, SiO J=2-1, CS J=2-1, HCO+ J=4-3 lines, etc. We discovered a bridge in the l-b-V space which connects the CND and the +20 km s-1 cloud. We interpret this as a gas streamer from outside to the CND.

  12. The Cosmology Large Angular Scale Surveyor (CLASS)

    NASA Technical Reports Server (NTRS)

    Harrington, Kathleen; Marriange, Tobias; Aamir, Ali; Appel, John W.; Bennett, Charles L.; Boone, Fletcher; Brewer, Michael; Chan, Manwei; Chuss, David T.; Colazo, Felipe; Denis, Kevin; Moseley, Samuel H.; Rostem, Karwan; Wollack, Edward

    2016-01-01

    The Cosmology Large Angular Scale Surveyor (CLASS) is a four telescope array designed to characterize relic primordial gravitational waves from in ation and the optical depth to reionization through a measurement of the polarized cosmic microwave background (CMB) on the largest angular scales. The frequencies of the four CLASS telescopes, one at 38 GHz, two at 93 GHz, and one dichroic system at 145/217 GHz, are chosen to avoid spectral regions of high atmospheric emission and span the minimum of the polarized Galactic foregrounds: synchrotron emission at lower frequencies and dust emission at higher frequencies. Low-noise transition edge sensor detectors and a rapid front-end polarization modulator provide a unique combination of high sensitivity, stability, and control of systematics. The CLASS site, at 5200 m in the Chilean Atacama desert, allows for daily mapping of up to 70% of the sky and enables the characterization of CMB polarization at the largest angular scales. Using this combination of a broad frequency range, large sky coverage, control over systematics, and high sensitivity, CLASS will observe the reionization and recombination peaks of the CMB E- and B-mode power spectra. CLASS will make a cosmic variance limited measurement of the optical depth to reionization and will measure or place upper limits on the tensor-to-scalar ratio, r, down to a level of 0.01 (95% C.L.).

  13. SkyView Virtual Telescope:

    NASA Astrophysics Data System (ADS)

    McGlynn, Thomas A.; McDonald, Laura M.; Scollick, Keith A.

    2015-11-01

    The SkyView Virtual telescope provides access to survey datasets ranging from radio through the gamma-ray regimes. Over 100 survey datasets are currently available. The SkyView library referenced here is used as the basis for the SkyView web site (at http://skvyiew.gsfc.nasa.gov) but is designed for individual use by researchers as well. SkyView's approach to access surveys is distinct from most other toolkits. Rather than providing links to the original data, SkyView attempts to immediately re-render the source data in the user-requested reference frame, projection, scaling, orientation, etc. The library includes a set of geometry transformation and mosaicking tools that may be integrated into other applications independent of SkyView.

  14. Diffractive X-Ray Telescopes

    NASA Technical Reports Server (NTRS)

    Skinner, Gerald K.

    2010-01-01

    Diffractive X-ray telescopes, using zone plates, phase Fresnel lenses, or related optical elements have the potential to provide astronomers with true imaging capability with resolution many orders of magnitude better than available in any other waveband. Lenses that would be relatively easy to fabricate could have an angular resolution of the order of micro-arc-seconds or even better, that would allow, for example, imaging of the distorted spacetime in the immediate vicinity of the super-massive black holes in the center of active galaxies. What then is precluding their immediate adoption? Extremely long focal lengths, very limited bandwidth, and difficulty stabilizing the image are the main problems. The history, and status of the development of such lenses is reviewed here and the prospects for managing the challenges that they present are discussed.

  15. SLAC Cosmic Ray Telescope Facility

    SciTech Connect

    Va'vra, J.

    2010-02-15

    SLAC does not have a test beam for the HEP detector development at present. We have therefore created a cosmic ray telescope (CRT) facility, which is presently being used to test the FDIRC prototype. We have used it in the past to debug this prototype with the original SLAC electronics before going to the ESA test beam. Presently, it is used to test a new waveform digitizing electronics developed by the University of Hawaii, and we are also planning to incorporate the new Orsay TDC/ADC electronics. As a next step, we plan to put in a full size DIRC bar box with a new focusing optics, and test it together with a final SuberB electronics. The CRT is located in building 121 at SLAC. We anticipate more users to join in the future. This purpose of this note is to provide an introductory manual for newcomers.

  16. Adaptive Optics for Large Telescopes

    SciTech Connect

    Olivier, S

    2008-06-27

    The use of adaptive optics was originally conceived by astronomers seeking to correct the blurring of images made with large telescopes due to the effects of atmospheric turbulence. The basic idea is to use a device, a wave front corrector, to adjust the phase of light passing through an optical system, based on some measurement of the spatial variation of the phase transverse to the light propagation direction, using a wave front sensor. Although the original concept was intended for application to astronomical imaging, the technique can be more generally applied. For instance, adaptive optics systems have been used for several decades to correct for aberrations in high-power laser systems. At Lawrence Livermore National Laboratory (LLNL), the world's largest laser system, the National Ignition Facility, uses adaptive optics to correct for aberrations in each of the 192 beams, all of which must be precisely focused on a millimeter scale target in order to perform nuclear physics experiments.

  17. Compact telescope for free-space communications

    NASA Astrophysics Data System (ADS)

    Draganov, Vladimir; James, Daryl G.

    2002-10-01

    Several types of telescopes are used for free space telecommunications. The most common are Cassegrain and Gregorian telescopes. The main difference between Cassegrain and Gregorian optical systems is that Gregorian telescopes employ a concave secondary mirror located beyond the focus of the primary mirror. This results in longer tube lengths, as the distance between mirrors is slightly more than the sum of their focal lengths, which is the reason Cassegrain systems are the most common. In addition, Gregorian telescopes produce an upright image, while Cassegrain telescopes produce an inverted image. FSONA is presenting a new compact optical system, which can be described as a modified Gregorian telescope. This telescope is ideally suited for free space optical communications but also has many other applications. The compact telescope is created from a standard Gregorian system by flipping the secondary mirror over a folding mirror installed approximately in the middle of the optical path between primary and secondary mirrors. In this manner, the primary mirror is constructed with a concentric "double curved" geometry, and a central obscuring folding mirror which matches the diameter of the smaller curve of the primary is mounted a short distance in front. This "double curved" geometry is easily produced using diamond turning technology, and the result is a compact telescope approximately 1/2 the length of a regular Gregorian telescope and roughly 2/3 the length of a Cassegrain telescope. There are several advantages to using this type of telescope: 1. The system is very compact. Telescope can be as short as 1/7 of the focal length of the system. 2. For Cassegrain and Gregorian systems it is very critical to keep tight tolerances on the centration between primary and secondary mirrors. The modified Gregorian telescope will always have perfect centration because both curved surfaces are machined at the same time on a diamond turning lathe. The folding mirror is flat

  18. The Onsala Twin Telescope Project

    NASA Astrophysics Data System (ADS)

    Haas, R.

    2013-08-01

    This paper described the Onsala Twin Telescope project. The project aims at the construction of two new radio telescopes at the Onsala Space Observatory, following the VLBI2010 concept. The project starts in 2013 and is expected to be finalized within 4 years. Z% O. Rydbeck. Chalmers Tekniska Högskola, Göteborg, ISBN 91-7032-621-5, 407-823, 1991. B. Petrachenko, A. Niell, D. Behrend, B. Corey, J. Böhm, P. Charlot, A. Collioud, J. Gipson, R. Haas, Th. Hobiger, Y. Koyama, D. MacMillan, Z. Malkin, T. Nilsson, A. Pany, G. Tuccari, A. Whitney, and J. Wresnik. Design Aspects of the VLBI2010 System. NASA/TM-2009-214180, 58 pp., 2009. R. Haas, G. Elgered, J. Löfgren, T. Ning, and H.-G. Scherneck. Onsala Space Observatory - IVS Network Station. In K. D. Baver and D. Behrend, editors, International VLBI Service for Geodesy and Astrometry 2011 Annual Report, NASA/TP-2012-217505, 88-91, 2012. H.-G. Scherneck, G. Elgered, J. M. Johansson, and B. O. Rönnäng. Phys. Chem. Earth, Vol. 23, No. 7-8, 811-823, 1998. A. R. Whitney. Ph.D. thesis, Dept. of Electrical engineering, MIT Cambridge, MA., 1974. B. A. Harper, J. D. Kepert, and J. D. Ginger. Guidelines for converting between various wind averaging periods in tropical cyclone conditions. WMO/TD-No. 1555, 64 pp., 2010 (available at \\url{http://www.wmo.int/pages/prog/www/tcp/documents/WMO_TD_1555_en.pdf})

  19. ESO Telescope Designer Raymond Wilson Wins Prestigious Kavli Award for Astrophysics

    NASA Astrophysics Data System (ADS)

    2010-06-01

    with four individual telescopes with 17.5 cm thick 8.2-metre mirrors. Active optics has contributed towards making the VLT the world's most successful ground-based observatory and will be an integral part of ESO's European Extremely Large Telescope (E-ELT) project. Active optics technology is also part of the twin 10-metre Keck telescopes, the Subaru telescope's 8.2-metre mirror and the two 8.1-metre Gemini telescopes. Co-prize winners Jerry Nelson and Roger Angel respectively pioneered the use of segmentation in telescope primary mirrors - as used on the Keck telescopes, and the development of lightweight mirrors with short focal ratios. A webcast from Oslo, Norway, announcing the prize winners is available at www.kavlifoundation.org and www.kavliprize.no. More information ESO, the European Southern Observatory, is the foremost intergovernmental astronomy organisation in Europe and the world's most productive astronomical observatory. It is supported by 14 countries: Austria, Belgium, the Czech Republic, Denmark, France, Finland, Germany, Italy, the Netherlands, Portugal, Spain, Sweden, Switzerland and the United Kingdom. ESO carries out an ambitious programme focused on the design, construction and operation of powerful ground-based observing facilities enabling astronomers to make important scientific discoveries. ESO also plays a leading role in promoting and organising cooperation in astronomical research. ESO operates three unique world-class observing sites in Chile: La Silla, Paranal and Chajnantor. At Paranal, ESO operates the Very Large Telescope, the world's most advanced visible-light astronomical observatory and VISTA, the world's largest survey telescope. ESO is the European partner of a revolutionary astronomical telescope ALMA, the largest astronomical project in existence. ESO is currently planning a 42-metre European Extremely Large optical/near-infrared Telescope, the E-ELT, which will become "the world's biggest eye on the sky".

  20. A CAMAC-based multi-channel digital delay generator for TACTIC gamma-ray telescope

    NASA Astrophysics Data System (ADS)

    Kaul, S. R.; Yadav, K. K.; Tickoo, A. K.; Koul, R.

    A programmable multi-channel CAMAC-based Digital Delay Generator (DDG) having a full scale delay of sim256ns and a resolution of sim 1ns has been developed for the TACTIC gamma-ray telescope array. The TACTIC telescope array comprises 4 times 10 m^2 altitude-azimuth mounted tracking light collectors arranged in a manner so that they represent the centre and three vertices of an equilateral triangle of side 20 m. The central element deploys a 349-pixel imaging camera and is referred to as the IMAGING Element (IE) while the three elements located at the vertices deploy low resolution 16 pixel cameras and are referred to as VERTEX Elements (VE). The function of the DDG is to achieve time synchronization between the trigger pulse from the IE and the 3 VE photomultiplier outputs so that the charge content of their respective 16 detector channels can be faithfully recorded. The unequal signal propagation time between the telescope elements arises because of their physical separation and the relative delay between them depends upon the pointing direction of the source which is being tracked by all the 4 telescope elements simultaneously. The design details of the DDG module (based on AD9500 IC) along with the edure for implementing the delays in the 3 VEs as a function of the source hour angle will be presented here.

  1. Adaptive Optics Imaging of Neptune with the W.M. Keck Telescope

    NASA Astrophysics Data System (ADS)

    Macintosh, B.; Max, C. E.; Roe, H.; Gibbard, S.; Gavel, D.; Acton, S.; Lai, O.; Wizinowich, P.; de Pater, I.; Ghez, A.; Baines, K.

    1999-09-01

    We present near-IR images of Neptune with a resolution of 0.05 arcseconds obtained with the new adaptive optics (AO) system at the 10-m W.M. Keck II telescope. The resolution and contrast of these images allows us to fit radiative transfer models to Neptune's clear atmosphere, completely uncontaminated by scattered light from bright storms or bands. We can measure for the first time the precise infrared spatial extent of storm features and calculate their reflectance in broad-band and methane-absorption near-IR bandpasses. The images show many bands and cloud features, and detect a bright southern-hemisphere complex that may be associated with a large dark spot similar to that seen by Voyager. These observations demonstrate that AO on an 8-10 meter telescope is a powerful new tool for studying objects in the outer solar system, surpassing the resolution of the NICMOS instrument on the Hubble Space Telescope by a factor of 2-4. This research was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract W-7405-ENG-48. It was supported in part by NASA grant NRA-97-OSS-04-98-053(R3281). The adaptive optics system on the Keck II telescope was funded by the W.M. Keck foundation under a grant to the California Association for Research in Astronomy, and by NASA.

  2. Overture: The grid classes

    SciTech Connect

    Brislawn, K.; Brown, D.; Chesshire, G.; Henshaw, W.

    1997-01-01

    Overture is a library containing classes for grids, overlapping grid generation and the discretization and solution of PDEs on overlapping grids. This document describes the Overture grid classes, including classes for single grids and classes for collections of grids.

  3. ALPACA: An Inexpensive but Uniquely Powerful Imaging Survey Telescope

    NASA Astrophysics Data System (ADS)

    Crotts, Arlin P.; ALPACA Consortium

    2006-12-01

    ALPACA (Advanced Liquid-mirror Probe of Astrophysics, Cosmology and Asteroids) is an 8-meter optical telescope destined for Cerro Tololo and designed to scan a strip of sky passing overhead and extending over 1000 square degrees. The imaging survey will be conducted in five photometric bands covering the optical waveband and allow for photometric descrimination of many source types, including supernova types and asteroid categories, and allow photometric redshift determination for both galaxies and supernovae. The ALPACA is intended to extend over at least a three years and reach a cumulative point-source detection of about 28th magnitude AB at 10-sigma. ALPACA will deliver nightly photometry for many classes of variable and moving objects. Most crucial, perhaps, will be the exquisitely deep, numerous and well-sampled multiband lightcurve sample for supernova, particularly SNe Ia to redshifts z 0.8. This is an excellent redshift range for dark energy model descrimination, but also can be used for unprecedentedly sensitive tests and improvements of the SN Ia standard candle relation. There are many other superlative projects that will be conducted with ALPACA data, including studies of high redshift galaxies, quasars and AGN, large scale structure, novae, variable stars, Galactic Bulge microlensing, Galactic structure, stellar populations, extrasolar planets, Kuiper Belt objects, Near-Earth objects and many other classes of targets. ALPACA is based on the 6-meter LZT (Large Zenith Telescope), which is currently operating in British Columbia and producing largely seeing-limited imaging. ALPACA has undergone conceptual design review and is now under design. Seeing tests are underway at sites on Cerro Tololo. We hope to achieve first light on ALPACA by late 2009. Proto-ALPACA is a stage of the project with the full-sized telescope with a smaller field of view, and will be first operational. ALPACA might eventually add instrumentation; a multiobject spectrograph is

  4. Mechanical cooler system for the next-generation infrared space telescope SPICA

    NASA Astrophysics Data System (ADS)

    Shinozaki, Keisuke; Ogawa, Hiroyuki; Nakagawa, Takao; Sato, Yoichi; Sugita, Hiroyuki; Yamawaki, Toshihiko; Mizutani, Tadahito; Matsuhara, Hideo; Kawada, Mitsunobu; Okabayashi, Akinobu; Tsunematsu, Shoji; Narasaki, Katsuhiro; Shibai, Hiroshi

    2016-07-01

    The Space Infrared Telescope for Cosmology and Astrophysics (SPICA) is a pre-project of JAXA in collaboration with ESA to be launched in the 2020s. The SPICA mission is to be launched into a halo orbit around the second Lagrangian point in the Sun-Earth system, which allows us to use effective radiant cooling in combination with a mechanical cooling system in order to cool a 2.5m-class large IR telescope below 8K. Recently, a new system design in particular thermal structure of the payload module has been studied by considering the technical feasibility of a cryogenic cooled telescope within current constraints of the mission in the CDF (Concurrent Design Facility) study of ESA/ESTEC. Then, the thermal design of the mechanical cooler system, for which the Japanese side is responsible, has been examined based on the CDF study and the feasible solution giving a proper margin has been obtained. As a baseline, 4K / 1K-class Joule-Thomson coolers are used to cool the telescope and thermal interface for Focal Plane Instruments (FPIs). Additionally, two sets of double stirling coolers (2STs) are used to cool the Telescope shield. In this design, nominal operation of FPIs can be kept when one mechanical cooler is in failure.

  5. Out of field of view rejection measurements of the ZIP telescope No. 2

    NASA Astrophysics Data System (ADS)

    Wong, W. K.; Wang, D.; Murdock, T. L.

    1983-01-01

    Recent re-measurement of the Out-of Field-of View-Rejection (OFVR) characteristics of the ZIP telescope No. 2 indicated that the Point Source Power Transmittance (PSPT) was increased by as much as a factor of 400 at one off-axis source orientation in comparison with the OFVR measurement of the identical telescope three years ago. The OFVR degradation was caused by particulate contamination of the telescope optical surfaces. After cleaning of the primary mirror, the OFVR performance was restored for off-axis angles of 2 degrees to 7 degrees, but the OFVR was still degraded by a factor of 2 to 20 for off-axis angles between 8 degrees to 15 degrees. This remaining degradation was also restored after cleaning of the secondary mirror. Since the original OFVR measurement, the telescope package was opened about 10 times in a Class 100 clean room environment for integration and testing and was exposed to Class 100 environment 3 to 4 days at a time. Subsequently, the telescope was sealed and stored in an evacuated vessel at room temperature for two years.

  6. Space Infrared Telescope Facility science instruments overview

    NASA Technical Reports Server (NTRS)

    Bothwell, Mary

    1991-01-01

    The Space Infrared Telescope Facility (SIRTF) will contain three cryogenically cooled infrared instruments: the Infrared Array Camera (IRAC), the Infrared Spectrograph (IRS), and the Multiband Infrared Photometer for SIRTF (MIPS). These instruments are sensitive to infrared radiation in the 1.8-1,200 micrometer range. This paper will discuss the three instruments' functional requirements and their accommodation in the SIRTF telescope system.

  7. The development of the Schmidt telescope

    NASA Astrophysics Data System (ADS)

    Wolfschmidt, G.

    2009-06-01

    % Bernhard Schmidt (1879-1935) was born in Estonia. After a few years of studying engineering he ran an optical workshop in Mittweida, Saxonia, between 1901 and 1927. Astronomers appreciated the quality of his telescopes. Starting in 1925, on behalf of the Hamburg Observatory, he developed a short focal length optical system with a large field of view. For this purpose, Schmidt moved his workshop to the observatory. He succeeded in inventing the ``Schmidt telescope'' which allows the imaging of a large field of the sky without any distortions. Schmidt's first telescope (spherical mirror diameter 0.44 m, correction plate 0.36 m diameter, aperture ratio 1:1.75, and focal length 0.625 m) has been used since 1962 at the Boyden Observatory in Bloemfontein/South Africa. Apart from his 0.36 m telescope, Schmidt produced a second larger one of 0.60 m aperture. Shortly after Schmidt's death, the director of the observatory published details on the invention and production of the Schmidt telescope. After World War II, Schmidt telescopes have been widely used. The first large Schmidt telescope, the ``Big Schmidt'' (1.26 m), Mount Palomar, USA, was completed in 1948. The 0.80 m Schmidt telescope of Hamburg Observatory, planned since 1936, finished in 1954, is now on Calar Alto/Spain.

  8. Proposed Integrated Radio-Telescope Network

    NASA Technical Reports Server (NTRS)

    Cohen, M. H.; Ewing, M. S.; Levy, G. S.; Mallis, R. K.; Readhead, A. C. S.; Smith, J. R.; Backer, D. C.

    1982-01-01

    Proposed network of radio telescopes, controlled by a central computer and managed by a single organization, offer potential for research on a scale that could not be matched by present privately and publicly-owned radio telescopes. With 10 antenna sites, network would establish base lines thousands of miles long. Antennas will be linked to computer center by telephone circuits.

  9. A Mechanical Analogue of the Refracting Telescope

    ERIC Educational Resources Information Center

    Vannoni, Maurizio; Molesini, Giuseppe; Sordini, Andrea; Straulino, Samuele

    2011-01-01

    The recent celebration of the discoveries made by Galileo four centuries ago has attracted new attention to the refracting telescope and to its use as an instrument for the observation of the night sky. This has offered the opportunity for addressing in the classroom the basic principles explaining the operation of the telescope. When doing so, a…

  10. Longer-baseline telescopes using quantum repeaters.

    PubMed

    Gottesman, Daniel; Jennewein, Thomas; Croke, Sarah

    2012-08-17

    We present an approach to building interferometric telescopes using ideas of quantum information. Current optical interferometers have limited baseline lengths, and thus limited resolution, because of noise and loss of signal due to the transmission of photons between the telescopes. The technology of quantum repeaters has the potential to eliminate this limit, allowing in principle interferometers with arbitrarily long baselines.

  11. Southern Fireworks above ESO Telescopes

    NASA Astrophysics Data System (ADS)

    1999-05-01

    New Insights from Observations of Mysterious Gamma-Ray Burst International teams of astronomers are now busy working on new and exciting data obtained during the last week with telescopes at the European Southern Observatory (ESO). Their object of study is the remnant of a mysterious cosmic explosion far out in space, first detected as a gigantic outburst of gamma rays on May 10. Gamma-Ray Bursters (GRBs) are brief flashes of very energetic radiation - they represent by far the most powerful type of explosion known in the Universe and their afterglow in optical light can be 10 million times brighter than the brightest supernovae [1]. The May 10 event ranks among the brightest one hundred of the over 2500 GRB's detected in the last decade. The new observations include detailed images and spectra from the VLT 8.2-m ANTU (UT1) telescope at Paranal, obtained at short notice during a special Target of Opportunity programme. This happened just over one month after that powerful telescope entered into regular service and demonstrates its great potential for exciting science. In particular, in an observational first, the VLT measured linear polarization of the light from the optical counterpart, indicating for the first time that synchrotron radiation is involved . It also determined a staggering distance of more than 7,000 million light-years to this GRB . The astronomers are optimistic that the extensive observations will help them to better understand the true nature of such a dramatic event and thus to bring them nearer to the solution of one of the greatest riddles of modern astrophysics. A prime example of international collaboration The present story is about important new results at the front-line of current research. At the same time, it is also a fine illustration of a successful collaboration among several international teams of astronomers and the very effective way modern science functions. It began on May 10, at 08:49 hrs Universal Time (UT), when the Burst

  12. Enhancing the Introductory Astronomical Experience with the Use of a Tablet and Telescope

    NASA Astrophysics Data System (ADS)

    Gill, Robert M.; Burin, Michael J.

    2013-02-01

    College and university general education (GE) classes are designed to broaden the understanding of all college and university students in areas outside their major interest. However, most GE classes are lecture type and do not facilitate hands-on experimental or observational activities related to the specific subject matter. Utilizing astronomy application programs (apps), currently available for the iPad and iPhone, in conjunction with a small inexpensive telescope, allows students unique hands-on experiences to explore and observe astronomical objects and concepts independently outside of class. These activities enhance the students' overall GE experience in a unique way not possible prior to the development of these technologies.

  13. Multilayer active shell mirrors for space telescopes

    NASA Astrophysics Data System (ADS)

    Steeves, John; Jackson, Kathryn; Pellegrino, Sergio; Redding, David; Wallace, J. Kent; Bradford, Samuel Case; Barbee, Troy

    2016-07-01

    A novel active mirror technology based on carbon fiber reinforced polymer (CFRP) substrates and replication techniques has been developed. Multiple additional layers are implemented into the design serving various functions. Nanolaminate metal films are used to provide a high quality reflective front surface. A backing layer of thin active material is implemented to provide the surface-parallel actuation scheme. Printed electronics are used to create a custom electrode pattern and flexible routing layer. Mirrors of this design are thin (< 1.0 mm), lightweight (2.7 kg/m2), and have large actuation capabilities. These capabilities, along with the associated manufacturing processes, represent a significant change in design compared to traditional optics. Such mirrors could be used as lightweight primaries for small CubeSat-based telescopes or as meter-class segments for future large aperture observatories. Multiple mirrors can be produced under identical conditions enabling a substantial reduction in manufacturing cost and complexity. An overview of the mirror design and manufacturing processes is presented. Predictions on the actuation performance have been made through finite element simulations demonstrating correctabilities on the order of 250-300× for astigmatic modes with only 41 independent actuators. A description of the custom metrology system used to characterize the active mirrors is also presented. The system is based on a Reverse Hartmann test and can accommodate extremely large deviations in mirror figure (> 100 μm PV) down to sub-micron precision. The system has been validated against several traditional techniques including photogrammetry and interferometry. The mirror performance has been characterized using this system, as well as closed-loop figure correction experiments on 150 mm dia. prototypes. The mirrors have demonstrated post-correction figure accuracies of 200 nm RMS (two dead actuators limiting performance).

  14. Remote secure observing for the Faulkes Telescopes

    NASA Astrophysics Data System (ADS)

    Smith, Robert J.; Steele, Iain A.; Marchant, Jonathan M.; Fraser, Stephen N.; Mucke-Herzberg, Dorothea

    2004-09-01

    Since the Faulkes Telescopes are to be used by a wide variety of audiences, both powerful engineering level and simple graphical interfaces exist giving complete remote and robotic control of the telescope over the internet. Security is extremely important to protect the health of both humans and equipment. Data integrity must also be carefully guarded for images being delivered directly into the classroom. The adopted network architecture is described along with the variety of security and intrusion detection software. We use a combination of SSL, proxies, IPSec, and both Linux iptables and Cisco IOS firewalls to ensure only authenticated and safe commands are sent to the telescopes. With an eye to a possible future global network of robotic telescopes, the system implemented is capable of scaling linearly to any moderate (of order ten) number of telescopes.

  15. Monitoring LMXBs with the Faulkes Telescope

    NASA Astrophysics Data System (ADS)

    Lewis, Fraser; Russell, D. M.; Fender, R. P.; Roche, P.

    The Faulkes Telescope Project is the educational arm of the Las Cumbres Observatory Global Telescope Network (LCOGT). It currently has two 2-metre robotic telescopes, located at Haleakala on Maui (FT North) and Siding Spring in Australia (FT South). It is planned to increase this to six 2-metre telescopes in the future, complemented by a network of 30-40 smaller (0.4 - 1 metre) telescopes providing 24 hour coverage of both northern and southern hemispheres. We are undertaking a monitoring project of 10 low-mass X-ray binaries (LMXBs) using FT North to study the optical continuum behaviour of X-ray transients in quiescence. The introduction of FT South in September 2006 allows us to extend this monitoring to include 17 southern hemisphere LMXBs. With new instrumentation, we also intend to expand this monitoring to include both infrared wavelengths and spectroscopy.

  16. James Webb Space Telescope Project (JWST) Overview

    NASA Technical Reports Server (NTRS)

    Dutta, Mitra

    2008-01-01

    This presentation provides an overview of the James Webb Space Telescope (JWST) Project. The JWST is an infrared telescope designed to collect data in the cosmic dark zone. Specifically, the mission of the JWST is to study the origin and evolution of galaxies, stars and planetary systems. It is a deployable telescope with a 6.5 m diameter, segmented, adjustable primary mirror. outfitted with cryogenic temperature telescope and instruments for infrared performance. The JWST is several times more sensitive than previous telescope and other photographic and electronic detection methods. It hosts a near infrared camera, near infrared spectrometer, mid-infrared instrument and a fine guidance sensor. The JWST mission objection and architecture, integrated science payload, instrument overview, and operational orbit are described.

  17. The Hexa-Pod-Telescope (HPT).

    NASA Astrophysics Data System (ADS)

    Schnur, G. F. O.; Stenvers, K.-H.; Pausch, K.

    The recently completed Hexa-Pod-Telescope (HPT) presents revolutionary new ideas on astronomical telescope design. Six mechanical struts support the HPT. The length of the six struts can be varied to permit the pointing and tracking of the HPT. Supporting the optical structure of the HPT from below allows to avoid superfluous balancing weights of normal telescopes. Compared to a classical telescope of the same mirror diameter the HPT realizes a weight reduction by a factor of 15! The HPT's primary mirror is realized as a hybrid structure consisting of a light-weight Carbon-Fibre-Reinforced Plastic (CFRP) structure permanently fixed to a 55 mm thin Zerodur faceplate, that forms the reflecting surface. Piezoelectrical ceramic positioners serve as active interface between the CFRP-structure and the optical surface. The low weight and extremely good optical quality of the HPT makes it an ideal candidate for larger telescopes in space, the moon and the stratosphere.

  18. Eyeglass. 1. Very large aperture diffractive telescopes.

    PubMed

    Hyde, R A

    1999-07-01

    The Eyeglass is a very large aperture (25-100-m) space telescope consisting of two distinct spacecraft, separated in space by several kilometers. A diffractive lens provides the telescope s large aperture, and a separate, much smaller, space telescope serves as its mobile eyepiece. Use of a transmissive diffractive lens solves two basic problems associated with very large aperture space telescopes; it is inherently launchable (lightweight, packagable, and deployable) it and virtually eliminates the traditional, very tight surface shape tolerances faced by reflecting apertures. The potential drawback to use of a diffractive primary (very narrow spectral bandwidth) is eliminated by corrective optics in the telescope s eyepiece; the Eyeglass can provide diffraction-limited imaging with either single-band (Deltalambda/lambda approximately 0.1), multiband, or continuous spectral coverage.

  19. Eyeglass. 1. Very large aperture diffractive telescopes

    SciTech Connect

    Hyde, R.A.

    1999-07-01

    The Eyeglass is a very large aperture (25{endash}100-m) space telescope consisting of two distinct spacecraft, separated in space by several kilometers. A diffractive lens provides the telescope{close_quote}s large aperture, and a separate, much smaller, space telescope serves as its mobile eyepiece. Use of a transmissive diffractive lens solves two basic problems associated with very large aperture space telescopes; it is inherently launchable (lightweight, packagable, and deployable) it and virtually eliminates the traditional, very tight surface shape tolerances faced by reflecting apertures. The potential drawback to use of a diffractive primary (very narrow spectral bandwidth) is eliminated by corrective optics in the telescope{close_quote}s eyepiece; the Eyeglass can provide diffraction-limited imaging with either single-band ({Delta}{lambda}/{lambda}{approximately}0.1), multiband, or continuous spectral coverage. {copyright} 1999 Optical Society of America

  20. A telescope with augmented reality functions

    NASA Astrophysics Data System (ADS)

    Hou, Qichao; Cheng, Dewen; Wang, Qiwei; Wang, Yongtian

    2016-10-01

    This study introduces a telescope with virtual reality (VR) and augmented reality (AR) functions. In this telescope, information on the micro-display screen is integrated to the reticule of telescope through a beam splitter and is then received by the observer. The design and analysis of telescope optical system with AR and VR ability is accomplished and the opto-mechanical structure is designed. Finally, a proof-of-concept prototype is fabricated and demonstrated. The telescope has an exit pupil diameter of 6 mm at an eye relief of 19 mm, 6° field of view, 5 to 8 times visual magnification , and a 30° field of view of the virtual image.

  1. Using Robotic Telescopes to Teach STEM Skills: Undergraduate and High School Students

    NASA Astrophysics Data System (ADS)

    McLin, Kevin M.

    2011-03-01

    Since 2004 the NASA Education and Public Outreach Group at Sonoma State University has run a small robotic telescope to be used for teaching at the undergraduate and high school levels. The telescope is part of the E/PO efforts of NASA's Fermi Gamma-ray Space Telescope. The telescope is generally run via a queue observing system as part of the PROMPT/Skynet program run out of the University of North Carolina. SSU E/PO Group members teach high school teachers and their students how to use the queue to request observations, how to retrieve their data and how to work with the images. Fundamentals of CCD imaging and data processing are taught, as are concepts basic to making scientific measurements, such as statistical and systematic errors, signal to noise and confidence in results. The telescope has been used in classrooms in high schools and small colleges and universities across the United States. We will describe some of the ways students have been able to access the telescope for their observing projects as well as innovative use of observations in general introductory astronomy classes. We will also describe some of the hurdles that must be overcome if the use of remote observatories is to become more widespread, especially at the high school level.

  2. Optomechanical and thermal design of the Multi-Application Solar Telescope for USO

    NASA Astrophysics Data System (ADS)

    Denis, Stefan; Coucke, Pierre; Gabriel, Eric; Delrez, Christophe; Venkatakrishnan, Parameshwaran

    2008-07-01

    The Multi-Application Solar Telescope (MAST) is a 50 cm diameter class telescope to be installed on the Udaipur Solar Observatory's Island on the Lake Fatehsagar in Udaipur, India. It is dedicated to solar observation. The telescope is designed, manufactured, assembled and installed on-site by the belgian company AMOS SA for the Udaipur Solar Observatory (USO), an academic division of the Physical Research Laboratory (PRL) in India. Despite its limited size, the telescope is expected to be competitive with respect to worldwide large and costly projects thanks to its versatility regarding science goals and also thanks to its demanding optomechanical and thermal specification. This paper describes the optomechanical and thermal design of this telescope and presents solutions adopted by AMOS to meet the specific requirements. The optical configuration of the telescope is based on an afocal off-axis gregorian combination integrated on an Alt.-Az. mechanical mount, with a suite of flat folding mirrors to provide the required stationary collimated beam.

  3. System Design and Implementation of the Virginia Tech Optical Satellite Tracking Telescope

    NASA Astrophysics Data System (ADS)

    Luciani, D.; Black, J.

    2016-09-01

    The Virginia Tech Optical Satellite Tracking Telescope (VTOST) aims to test the feasibility of a commercial off-the-shelf (COTS) designed tracking system for Space Situational Awareness (SSA) data contribution. A novel approach is considered, combining two COTS systems, a high-powered telescope, built for astronomy purposes, and a larger field of view (FOV) camera. Using only publicly available two-line element sets (TLEs), orbital propagation accuracy degrades quickly with time from epoch and is often not accurate enough to task a high-powered, small FOV telescope. Under this experimental approach, the larger FOV camera is used to acquire and track the resident space object (RSO) and provide a real-time pointing update to allow the high-powered telescope to track the RSO and provide possible resolved imagery. VTOST is designed as a remotely taskable sensor, based on current network architecture, capable of serving as a platform for further SSA studies, including unresolved and resolved imagery analysis, network tasking, and orbit determination. Initial design considerations are based on the latest Raven class and other COTS based telescope research, including research by the Air Force Research Lab (AFRL), ExoAnalytic Solutions, and other university level telescope projects. A holistic system design, including astronomy, image processing, and tracking methods, in a low-budget environment is considered. Method comparisons and results of the system design process are presented.

  4. Perfecting 'a sharper image': telescope-making and the dissemination of technical knowledge, 1700-1820

    NASA Astrophysics Data System (ADS)

    Cameron, Gary L.

    2012-07-01

    Telescopes, reflecting telescopes in particular, underwent considerable development during the eighteenth century. Two classes of telescope maker, the for-profit artisan and the amateur 'gentleman-philosopher,' learned techniques of optical fabrication and testing and produced usable astronomical instruments. One means of disseminating technical knowledge was via the book. The year 1738 saw the publication of a highly-influential book, Robert Smith's A Compleat System of Opticks, a work that included detailed information on telescope-making. It was this book that helped spark the astronomical career of William Herschel, and with Smith's information Herschel produced large reflecting telescopes of exquisite quality. However, artisan-opticians, even the renowned James Short, appear to have cut corners on a portion of their production, thus permitting the sale of some instruments of inferior quality. The reasons for this were clearly economical in nature: artisans depending on telescope sales to earn a living simply could not afford the time required for perfection. The mere presence of written works disseminating technical

  5. ALMA Telescope Reaches New Heights

    NASA Astrophysics Data System (ADS)

    2009-09-01

    ball at a distance of nine miles, and to keep their smooth reflecting surfaces accurate to less than the thickness of a human hair. Once the transporter reached the high plateau it carried the antenna to a concrete pad -- a docking station with connections for power and fiber optics -- and positioned it with an accuracy of a small fraction of an inch. The transporter is guided by a laser steering system and, just like some cars, also has ultrasonic collision detectors. These sensors ensure the safety of the state-of-the-art antennas as the transporter drives them across what will soon be a rather crowded plateau. Ultimately, ALMA will have at least 66 antennas distributed over about 200 pads, spread over distances of up to 11.5 miles and operating as a single, giant telescope. Even when ALMA is fully operational, the transporters will be used to move the antennas between pads to reconfigure the telescope for different kinds of observations. This first ALMA antenna at the high site will soon be joined by others, and the ALMA team looks forward to making their first observations from the Chajnantor plateau. They plan to link three antennas by early 2010, and to make the first scientific observations with ALMA in the second half of 2011. ALMA will help astronomers answer important questions about our cosmic origins. The telescope will observe the Universe using light with millimeter and submillimeter wavelengths, between infrared light and radio waves in the electromagnetic spectrum. Light at these wavelengths comes from some of the coldest, and from some of the most distant objects in the cosmos. These include cold clouds of gas and dust where new stars are being born, or remote galaxies towards the edge of the observable universe. The Universe is relatively unexplored at submillimeter wavelengths, as the telescopes need extremely dry atmospheric conditions, such as those at Chajnantor, and advanced detector technology. The Atacama Large Millimeter/submillimeter Array

  6. The absolute calibration strategy of the ASTRI SST-2M telescope proposed for the Cherenkov Telescope Array and its external ground-based illumination system

    NASA Astrophysics Data System (ADS)

    Segreto, A.; Maccarone, M. C.; Catalano, O.; Biondo, B.; Gargano, C.; La Rosa, G.; Russo, F.; Sottile, G.; Fiorini, M.; Incorvaia, S.; Toso, G.

    2016-07-01

    ASTRI is the end-to-end prototype for the CTA small-size class of telescopes in a dual-mirror configuration (SST-2M) proposed by the Italian National Institute of Astrophysics (INAF) in the framework of the Cherenkov Telescope Array. ASTRI SST-2M has been installed at the Serra La Nave Astrophysical Observatory on Mount Etna (Sicily) and its Performance Verification Phase will start in autumn 2016. For the relative pixel calibration and gain monitoring, the ASTRI SST-2M camera is equipped with an internal illumination device, while an external, portable, illumination system, placed at a few km distance from the telescope, will be used for the absolute end-to-end calibration of the telescope spectral response. Moreover analysis of signals induced in the camera pixels by the night sky background (diffuse emission and reference stars) will be used to monitor the long term evolution of the telescope calibration. We present an overview of the ASTRI SST-2M absolute calibration strategy and the external illuminating device that will be used for its spectral calibration

  7. Beyond the Hubble Space Telescope: Early Development of the Next Generation Space Telescope

    NASA Astrophysics Data System (ADS)

    Smith, Robert W.; Patrick McCray, W.

    In this paper we investigate the early history of what was at first called the Next Generation Space Telescope, later to be renamed the James Webb Space Telescope. We argue that the initial ideas for such a Next Generation Space Telescope were developed in the context of the planning for a successor to the Hubble Space Telescope. Much the most important group of astronomers and engineers examining such a successor was based at the Space Telescope Science Institute in Baltimore. By the late 1980s, they had fashioned concepts for a successor that would work in optical, ultraviolet and infrared wavelengths, concepts that would later be regarded as politically unrealistic given the costs associated with them. We also explore how the fortunes of the planned Next Generation Space Telescope were intimately linked to that of its "parent," the Hubble Space Telescope.

  8. Development of the NASA MCAT Auxiliary Telescope for Orbital Debris Research

    NASA Technical Reports Server (NTRS)

    Frith, James; Lederer, Susan; Cowardin, Heather; Buckalew, Brent; Hickson, Paul; Anz-Meador, Phillip

    2016-01-01

    The National Aeronautical and Space Administration (NASA) has recently deployed the Meter Class Autonomous Telescope (MCAT) to Ascension Island. MCAT will provide NASA with a dedicated optical sensor for observations of orbital debris with the goal of statistically sampling the orbital and photometric characteristics of the population from low Earth to Geosynchronous orbits. Additionally, a small auxiliary telescope, co-located with MCAT, is being deployed to augment its observations by providing near-simultaneous photometry and astrometry, as well as offloading low priority targets from MCAT's observing queue. It will also be available to provide observational measurements to the Space Surveillance Network for the United States Air Force.

  9. Elucidation of the Corrosion Inhibition of Mild Steel in 1.0 M HCl by Catechin Monomers from Commercial Green Tea Extracts

    NASA Astrophysics Data System (ADS)

    Nofrizal, S.; Rahim, Afidah A.; Saad, Bahruddin; Bothi Raja, P.; Shah, Affaizza M.; Yahya, S.

    2012-04-01

    The inhibitive action of commercial green tea extracts on mild steel (MS) in a 1.0 M hydrochloric acid solution was investigated by weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). A high-performance liquid chromatographic (HPLC) analysis showed conclusively that of the eight catechin monomers and caffeine found in the original extracts, only four components were responsible for the inhibition of MS. The decreasing adsorption capacity of monomers on MS is related to the stereochemistry of molecules and the number of phenolic groups, and it is as follows: epigallocatechin gallate > epicatechin gallate > epigallocatechin > epicatechin. Adsorption of green tea extract constituent was found to follow Langmuir adsorption isotherm and the calculated Gibb's free energy values indicated the physisorption of inhibitor over MS surface. Physisorption was supported well by the potential zero charge (PZC) and molecular surface energy-level calculations.

  10. Synergistic of a coumarin derivative with potassium iodide on the corrosion inhibition of aluminum alloy in 1.0 M H2SO4

    NASA Astrophysics Data System (ADS)

    Mohamad, Abu Bakar; Kadhum, Abdul Amir H.; Al-Amiery, Ahmed A.; Ying, Lim Chai; Musa, Ahmed Y.

    2014-05-01

    Synergistic effects of the addition of KI on the corrosion inhibitive performance of a coumarin derivative on an aluminum alloy in 1.0 M H2SO4 at different temperatures were studied using various electrochemical measurements. Density functional theory was used to calculate the quantum chemical parameters of the coumarin derivative. The experimental results showed that the coumarin derivative is considered as a mixedtype inhibitor. The corrosion potential values were almost unchanged upon the addition of PBBC to the acidic solution. The inhibition efficiency increases with increasing inhibitor concentration and increases further in the presence of 6.02 mM KI but decreases significantly at higher temperature. The adsorption of PBBC obeyed the Langmuir isotherm, and being chemically adsorbed at lower temperatures, while physical adsorption is favoured at higher temperature. The theoretical results indicated that the coumarin derivative was adsorbed onto the surface of Al2024 through the sulfur, oxygen and nitrogen atoms.

  11. CsI Calorimeter for a Compton-Pair Telescope

    NASA Astrophysics Data System (ADS)

    Grove, Eric J.

    We propose to build and test a hodoscopic CsI(Tl) scintillating-crystal calorimeter for a medium-energy γ-ray Compton and pair telescope. The design and technical approach for this calorimeter relies deeply on heritage from the Fermi LAT CsI Calorimeter, but it dramatically improves the low-energy performance of that design by reading out the scintillation light with silicon photomultipliers (SiPMs), making the technology developed for Fermi applicable in the Compton regime. While such a hodoscopic calorimeter is useful for an entire class of medium-energy γ-ray telescope designs, we propose to build it explicitly to support beam tests and balloon flight of the Proto-ComPair telescope, the development and construction of which was funded in a four-year APRA program beginning in 2015 ("ComPair: Steps to a Medium Energy γ-ray Mission" with PI J. McEnery of GSFC). That award did not include funding for its CsI calorimeter subsystem, and this proposal is intended to cover that gap. ComPair is a MIDEX-class instrument concept to perform a high-sensitivity survey of the γ-ray sky from 0.5 MeV to 500 MeV. ComPair is designed to provide a dramatic increase in sensitivity relative to previous instruments in this energy range (predominantly INTEGRAL/SPI and Compton COMPTEL), with the same transformative sensitivity increase – and corresponding scientific return– that the Fermi Large Area Telescope provided relative to Compton EGRET. To enable transformative science over a broad range of MeV energies and with a wide field of view, ComPair is a combined Compton telescope and pair telescope employing a silicon-strip tracker (for Compton scattering and pair conversion and tracking) and a solid-state CdZnTe calorimeter (for Compton absorption) and CsI calorimeter (for pair calorimetry), surrounded by a plastic scintillator anti-coincidence detector. Under the current proposal, we will complete the detailed design, assembly, and test of the CsI calorimeter for the risk

  12. Evaluating SLOOH Robotic Telescopes for Formal Educational Use

    NASA Astrophysics Data System (ADS)

    Gershun, D.; Berryhill, K. J.; Slater, T. F.

    2012-12-01

    The past several years has seen a gradual shift from telescopes being used only by top researchers to a case where educators across the STEM spectrum now have access to quality telescopes. This has been made possible by equipping telescopes to be controlled over the internet, either robotically which requires no human interaction during observation, or remotely which retain full user controllability. Education researchers around the world have recently focused on applications in elementary and secondary education (McKinnon & Geissinger 2002, Sadler et al. 2007). Responding to this paradigm shift, graduate students and faculty at the University of Wyoming and Center for Physic & Astronomy Education Research (www.caperteam.com) are dedicating time to explore this further at the undergraduate level, in order to better advise STEM educators of the most effective technological resources and curriculum development. Current research focuses on evaluating the academic merit of using SLOOH Space Camera in a summer online course offered by the University of Wyoming Outreach Program. SLOOH has robotic telescopes in the Canary Islands and La Dehesa, Chile. This evaluation will provide valuable data on an emerging technology as well as serve to advise future introductory astronomy sections at the University of Wyoming on the use of similar internet-controlled telescopes. The eight-week course exposed nine graduate science education students to basic night sky observing knowledge as well as provided hands-on experience using several robotic and remote observatories1,2,3,4. This mixed-methods case study collected data in the forms of six focus-group recordings, pre- and post-tests from all participants, a post-class survey, and general observations by the lead researcher. Transcripts and comments are coded to determine the most important features of SLOOH, and testing measures are analyzed to gauge the incoming and outgoing knowledge of participants. Analysis of testing measures

  13. You can teach an old dog new tricks: the Mayall 4-meter telescope

    NASA Astrophysics Data System (ADS)

    Sharp, Nigel A.; Claver, Charles F.; Green, Richard F.; Bulau, Scott E.; Mills, David; Abraham, Antony A.

    2003-02-01

    The Mayall 4-meter telescope on Kitt Peak is a successful and productive telescope now approaching its thirtieth anniversary. Originally designed at 150 inches, built at 158 inches, and with an effective aperture or 3.81m, it is from the generation of thick mirror, equatorially mounted telescopes. At a moderate altitude site, the Mayall had in the past upheld the prejudice that ground-based observing delivers about 1" seeing at best, and that it is no surprise to be considerably fuzzier. Changes in engineering, computer control, and our understanding of telescope seeing, have led to the new generation of lightweight mirrors with complex active support and advanced thermal control, running on altitude-azimuth mounts inside compact, low-volume enclosures. Such telescopes routinely deliver sub-arcsecond seeing, often down below 0.5" even from ‘traditional" sites, and even sharper from higher and more remote sites to which access has been developed over recent decades. Nevertheless, what we have learned can be successfully applied to older telescopes: the Mayall telescope is a case in point, since it now regularly provides sub-arcsecond image quality. We discuss the significant improvements in thermal management and active control of the Mayall system over the last several years, as well as the difficulty of evaluating such changes, especially separating different effects. We also discuss future adjustments to and tuning of existing sub-systems, possible changes to the telescope environment, and planned new features. It takes effort and continual attention to detail, but older facilities can still be world class.

  14. The Perkins Telescope in the 21st Century: An NSF PREST Project

    NASA Astrophysics Data System (ADS)

    Janes, K. A.; Buie, M. W.; Bosh, A. S.; Clemens, D. P.; Jackson, J. M.

    2005-12-01

    With the help of a grant under the NSF "Program for Research and Education with Small Telescopes (PREST)," Boston University and Lowell Observatory are engaged in a project to improve the performance of the 1.83-meter Perkins Telescope on Anderson Mesa near Flagstaff, Arizona. Our goal is to bring the Perkins Telescope into the 21st century, to create effective resources in support of the scientific and educational missions of our two institutions and the larger community. Over the past several years we have re-instrumented the telescope; two facility-class instruments, Mimir, a wide-field infrared imager, polarimeter and spectrometer and PRISM, an optical counterpart, are now in operation at the Perkins Telescope. The new instrumentation at the Perkins will give our partnership and visiting observers access to an important niche in "observation space" not readily available elsewhere. Wide-field polarimetry and imaging and multi-object low-resolution spectroscopy are now possible across the spectrum from the near uv to the thermal IR. We are well-placed for surveys and synoptic studies, ranging from monitoring polarization variations in blazars to mapping the galactic magnetic field to tracking Kuiper-belt objects. Our PREST project includes four components: Thermal management to improve the seeing at the telescope, upgrades to the instrumentation, productivity enhancements to the facility, and integration of the Boston University access to the telescope into our graduate and undergraduate educational programs. In the first year of the PREST grant we have set up a visitor program (see www.lowell.edu/VisitingObservers/), established a graduate-student-in-residence program, installed fans and ductwork around the telescope and dome to improve seeing, and completed a student-led project to construct an innovative grism for optical spectroscopy based on a volume-phase holographic grating.

  15. The Automated Planet Finder telescope's automation and first three years of planet detections

    NASA Astrophysics Data System (ADS)

    Burt, Jennifer

    2016-08-01

    The Automated Planet Finder (APF) is a 2.4m, f/15 telescope located at the UCO's Lick Observatory, atop Mt. Hamilton. The telescope has been specifically optimized to detect and characterize extrasolar planets via high precision, radial velocity (RV) observations using the high-resolution Levy echelle spectrograph. The telescope has demonstrated world-class internal precision levels of 1 m/s when observing bright, RV standard stars. Observing time on the telescope is divided such that ˜80% is spent on exoplanet related research and the remaining ˜20% is made available to the University of California consortium for other science goals. The telescope achieved first light in 2013, and this work describes the APF's early science achievements and its transition from a traditional observing approach to a fully autonomous facility. First we provide a characteristic look at the APF telescope and the Levy spectrograph, focusing on the stability of the instrument and its performance on RV standard stars. Second, we describe the design and implementation of the dynamic scheduling software which has been running our team's nightly observations on the APF for the past year. Third, we discuss the detection of a Neptune-mass planet orbiting the nearby, low-mass star GL687 by the APF in collaboration with the HIRES instrument on Keck I. Fourth, we summarize the APF's detection of two multi-planet systems: the four planet system orbiting HD 141399 and the 6 planet system orbiting HD 219134. Fifth, we expand our science focus to assess the impact that the APF - with the addition of a new, time-varying prioritization scheme to the telescope's dynamic scheduling software - can have on filling out the exoplanet Mass-Radius diagram when pursuing RV follow-up of transiting planets detected by NASA's TESS satellite. Finally, we outline some likely next science goals for the telescope.

  16. Infrastructure for large space telescopes

    NASA Astrophysics Data System (ADS)

    MacEwen, Howard A.; Lillie, Charles F.

    2016-10-01

    It is generally recognized (e.g., in the National Aeronautics and Space Administration response to recent congressional appropriations) that future space observatories must be serviceable, even if they are orbiting in deep space (e.g., around the Sun-Earth libration point, SEL2). On the basis of this legislation, we believe that budgetary considerations throughout the foreseeable future will require that large, long-lived astrophysics missions must be designed as evolvable semipermanent observatories that will be serviced using an operational, in-space infrastructure. We believe that the development of this infrastructure will include the design and development of a small to mid-sized servicing vehicle (MiniServ) as a key element of an affordable infrastructure for in-space assembly and servicing of future space vehicles. This can be accomplished by the adaptation of technology developed over the past half-century into a vehicle approximately the size of the ascent stage of the Apollo Lunar Module to provide some of the servicing capabilities that will be needed by very large telescopes located in deep space in the near future (2020s and 2030s). We specifically address the need for a detailed study of these servicing requirements and the current proposals for using presently available technologies to provide the appropriate infrastructure.

  17. Telescopes for the 1980s

    NASA Astrophysics Data System (ADS)

    Neugebauer, G.

    In the last decades, astronomy has been changed in a number of significant ways. The number of large optical telescopes with diameters on the order of or larger than 2.3 m has increased from 3 shortly after World War II to about 20 at the present time. Whereas prewar astronomy was largely devoted to the visual wavelengths (0.3-0.8 μm), astronomical observations currently span the range from γ ray wavelengths to the longest radio wavelengths. Most significantly, astronomy outside conventional optical astronomy has developed into sophisticated disciplines rather than experimental explorations. Many of the observational advances at the forefront of astronomy now come from other than visual observations. Along with these changes have come fundamental changes in visual astronomy itself. Observations with photographic plates are the exception rather than the rule at most large observatories. Instead, electronic cameras are in common use. A second change, especially in the United States, is that the funding has gone from largely private funding (e.g., the Carnegie Institution of Washington) to funding with the government providing a main share of the support. Indeed, the government has provided the total funding for those disciplines, like X ray astronomy, which use space-borne platforms. These changes have also affected the character of doing astronomy, and astronomers have become much more politically active on the national science scene.

  18. Parallaxes with Hubble Space Telescope

    NASA Astrophysics Data System (ADS)

    Benedict, G. F.; McArthur, B. E.; Harrison, T. E.; Lee, J.; Slesnick, C. L.; HST Astrometry Science Team

    2001-11-01

    We report on parallaxes for astrophysically interesting stars obtained with the Fine Guidance Sensor interferometer on Hubble Space Telescope. These objects include the central star of the planetary nebula NGC 6853, the cataclysmic variable TV Col, and the distance scale calibrators RR Lyr and delta Cep. We will discuss our considerable efforts to characterize the reference stars associated with each prime target, necessary to effect the correction from relative to absolute parallax. These targets were originally chosen by L. W. Fredrick in 1980. We compare these and our past results with all past, non-HST determinations, including those from HIPPARCOS for our brighter targets. The HST Astrometry Sceince Team consists of W. H. Jefferys , P.I., G. F. Benedict, deputy P.I., B. E. McArthur, P. J. Shelus, R. Duncombe (UTexas), E. Nelan (STScI), W. van Altena and J. Lee (Yale), O. Franz and L. Wasserman (Lowell Obs.), and L. Fredrick (UVirginia). We gratefully acknowledge the support of NASA grant NAG5-1603 and our many supporters at STScI and Goddard Spaceflight Center. We thank R. Patterson, J. Rhee, and S. Majewski (UVirginia) and T. Montemayor (UTexas) for assistance with reference star photometry.

  19. Celestial Objects for Common Telescopes

    NASA Astrophysics Data System (ADS)

    Webb, Thomas William

    2010-06-01

    Introduction; Part I. The Instrument and the Observer: 1. The telescope; 2. The mode of observation; Part II. The Solar System: 1. The Sun; 2. Mercury; 3. Venus; 4. The Moon; 5. Index to the map of the moon; 6. Mars; 7. Jupiter; 8. Saturn; 9. Uranus and Neptune; 10. Comets; Part III. The Starry Heavens: 1. Double stars, clusters, and nebulae; 2. Andromeda; 3. Anser; 4. Antinous; 5. Aquarius; 6. Aquila; 7. Argo Navis; 8. Aries; 9. Auriga; 10. Boötes; 11. Camelopardus; 12. Cancer; 13. Canes Venatici; 14. Canis Major; 15. Canis Minor; 16. Capricornus; 17. Cassiopea; 18. Cepheus; 19. Cetus; 20. Clypeus Sobieskii; 21. Coma Berenices; 22. Corona Borealis; 23. Corvus; 24. Crater; 25. Cygnus; 26. Delphinus; 27. Draco; 28. Equuleus; 29. Eridanus; 30. Gemini; 31. Hercules; 32. Hydra; 33. Lacerta; 34. Leo; 35. Leo Minor; 36. Lepus; 37. Libra; 38. Lynx; 39. Lyra; 40. Monoceros; 41. Ophiuchus; 42. Orion; 43. Pegasus; 44. Perseus; 45. Pisces; 46. Sagitta; 47. Sagittarius; 48. Scorpio; Scutum, see Clypeus, Sobieskii; 49. Serpens; 50. Sextans; 51. Taurus; 52. Taurus Poniatowskii; 53. Triangulum; 54. Ursa Major; 55. Ursa Minor; 56. Virgo; 57. Vulpecula.

  20. Parametric Cost Models for Space Telescopes

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Henrichs, Todd; Dollinger, Courtney

    2010-01-01

    Multivariable parametric cost models for space telescopes provide several benefits to designers and space system project managers. They identify major architectural cost drivers and allow high-level design trades. They enable cost-benefit analysis for technology development investment. And, they provide a basis for estimating total project cost. A survey of historical models found that there is no definitive space telescope cost model. In fact, published models vary greatly [1]. Thus, there is a need for parametric space telescopes cost models. An effort is underway to develop single variable [2] and multi-variable [3] parametric space telescope cost models based on the latest available data and applying rigorous analytical techniques. Specific cost estimating relationships (CERs) have been developed which show that aperture diameter is the primary cost driver for large space telescopes; technology development as a function of time reduces cost at the rate of 50% per 17 years; it costs less per square meter of collecting aperture to build a large telescope than a small telescope; and increasing mass reduces cost.

  1. Ground-Based Telescope Parametric Cost Model

    NASA Technical Reports Server (NTRS)

    Stahl, H. Philip; Rowell, Ginger Holmes

    2004-01-01

    A parametric cost model for ground-based telescopes is developed using multi-variable statistical analysis, The model includes both engineering and performance parameters. While diameter continues to be the dominant cost driver, other significant factors include primary mirror radius of curvature and diffraction limited wavelength. The model includes an explicit factor for primary mirror segmentation and/or duplication (i.e.. multi-telescope phased-array systems). Additionally, single variable models based on aperture diameter are derived. This analysis indicates that recent mirror technology advances have indeed reduced the historical telescope cost curve.

  2. Hubble Space Telescope Primer for Cycle 21

    NASA Astrophysics Data System (ADS)

    Gonzaga, S.; et al.

    2012-12-01

    The Hubble Space Telescope Primer for Cycle 21 is a companion document to the HST Call for Proposals1. It provides an overview of the Hubble Space Telescope (HST), with basic information about telescope operations, instrument capabilities, and technical aspects of the proposal preparation process. A thorough understanding of the material in this document is essential for the preparation of a competitive proposal. This document is available as an online HTML document and a PDF file. The HTML version, optimized for online browsing, contains many links to additional information. The PDF version is optimized for printing, but online PDF readers have search capabilities for quick retrieval of specific information.

  3. Dual-Channel Multi-Purpose Telescope

    NASA Technical Reports Server (NTRS)

    Howard, Joseph M.; Content, David

    2009-01-01

    A dual-channel telescope allows for a wide-field telescope design wit h a good, narrow field channel of fewer surfaces for shorter-wavelen gth or planet-finding applications. The design starts with a Korsch three-mirror-anastigmat (TMA) telescope that meets the mission criter ia for image quality over a wide field of view. The internal image a t the Cassegrain focus is typically blurry due to the aberration bala ncing among the three mirrors. The Cassegrain focus is then re-optim ized on the axis of the system where the narrow field channel instru ment is picked off by bending the primary mirror.

  4. Telescoping cylindrical piezoelectric fiber composite actuator assemblies

    NASA Technical Reports Server (NTRS)

    Allison, Sidney G. (Inventor); Shams, Qamar A. (Inventor); Fox, Robert L. (Inventor); Fox, legal representative, Christopher L. (Inventor); Fox Chattin, legal representative, Melanie L. (Inventor)

    2010-01-01

    A telescoping actuator assembly includes a plurality of cylindrical actuators in a concentric arrangement. Each cylindrical actuator is at least one piezoelectric fiber composite actuator having a plurality of piezoelectric fibers extending parallel to one another and to the concentric arrangement's longitudinal axis. Each cylindrical actuator is coupled to concentrically-adjacent ones of the cylindrical actuators such that the plurality of cylindrical actuators can experience telescopic movement. An electrical energy source coupled to the cylindrical actuators applies actuation energy thereto to generate the telescopic movement.

  5. NASA capabilities roadmap: advanced telescopes and observatories

    NASA Technical Reports Server (NTRS)

    Feinberg, Lee D.

    2005-01-01

    The NASA Advanced Telescopes and Observatories (ATO) Capability Roadmap addresses technologies necessary for NASA to enable future space telescopes and observatories collecting all electromagnetic bands, ranging from x-rays to millimeter waves, and including gravity-waves. It has derived capability priorities from current and developing Space Missions Directorate (SMD) strategic roadmaps and, where appropriate, has ensured their consistency with other NASA Strategic and Capability Roadmaps. Technology topics include optics; wavefront sensing and control and interferometry; distributed and advanced spacecraft systems; cryogenic and thermal control systems; large precision structure for observatories; and the infrastructure essential to future space telescopes and observatories.

  6. New technology for large optical telescopes

    NASA Astrophysics Data System (ADS)

    de Jonge, M. J.

    1983-05-01

    A recurrent topic arising in the discussions about new generation large optical telescopes is related to the economic advantages of lightweight reflector surfaces. A description is given of new technologies which might be suited for the construction of lightweight telescopes of low cost. One technology involves the use of sandwich structures, which include aluminum layers, separated by aluminum honeycomb layers. The availability of these structures, which have been developed for aircraft manufacture, has led various groups to study the feasibility of a use of sandwich materials for the manufacture of highly accurate reflecting surfaces, as required for millimeter and submillimeter wave telescopes. The results of these studies are discussed.

  7. MI-6: Michigan interferometry with six telescopes

    NASA Astrophysics Data System (ADS)

    Monnier, John D.; Anderson, M.; Baron, F.; Berger, D. H.; Che, X.; Eckhause, T.; Kraus, S.; Pedretti, E.; Thureau, N.; Millan-Gabet, R.; ten Brummelaar, T.; Irwin, P.; Zhao, M.

    2010-07-01

    Based on the success of four-telescope imaging with the Michigan Infrared Combiner (MIRC) on the CHARA Array, our Michigan-based group will now upgrade our system to combine all six CHARA telescope simultaneously. In order to make this observationally efficient, we have had to improve a number of subsystems and commission new ones, including the new CHAMP fringe tracker, the introduction of photometric channels, the upgrading of the realtime operating systems, and the obvious hardware and software upgrades of the control system and the data pipeline. Here we will discuss the advantages of six-telescope operation, outline our upgrade plans and discuss our current progress.

  8. Design analysis of the astrometrical telescope facility

    NASA Technical Reports Server (NTRS)

    Huang, Chunsheng; Lawrence, George; Levy, Eugene; Mcmillan, Robert

    1989-01-01

    This paper presents a detailed analysis of a space-based telescope requiring an accuracy of 50 pico radians. A relationship between the geometric centroid of a diffraction image and wave aberrations is derived by a combination approach of diffraction optics and geometric optics. Based on sensitivity of the centroid, one-mirror and two-mirror aplanatic telescopes are investigated. The comparison among three telescopes, parabola, Schwartzschild and Ritchey-Chretien are quantitatively carried out in terms of their sensitivities to the systematic errors and random errors. The study shows that the Ritchey-Chretien design is the most preferable.

  9. Dynamics and Control for a Small Telescope

    NASA Astrophysics Data System (ADS)

    Berná, J. A.; Pérez, M.; Bernabeu, G.

    1998-06-01

    Our main goal is to determine the dynamic equations of a certain complex system, as is the case of the mechanical system for a small aperture telescope. Causes of this complexity are: the lack of documents about the operation of the elements belonging to the system, and the variation of dynamics with respect to the time and the position of the telescope. To check that we have obtained a valid set of dynamic equations, we will design a computer control system that will implement a self-guide system for the telescope.

  10. Support structures for large infrared telescopes

    NASA Technical Reports Server (NTRS)

    Hedgepeth, J. M.

    1984-01-01

    An infrared telescope requires an accuracy of its reflecting surfaces of less than a micrometer. Future missions may require such accuracy from telescopes that are 20 meters or larger in diameter. The structure for supporting such a telescope will most probably take the form of a deep truss. Various approaches for constructing the primary mirror in space are illustrated. One that employs automated deployment of interconnected reflector-structure modules was described in detail. Estimates were made of the precision obtainable with properly configured truss structures and the required ability of active control systems for achieving the desired accuracy.

  11. Large X-class Flare Erupting on Jan. 27

    NASA Video Gallery

    On Jan. 27, 2012 a large X-class flare erupted from an active region near the solar west limb. Seen here is a time series of the flare captured by the X-ray telescope on Hinode. These images repres...

  12. Las Cumbres Observatory Global Telescope Network: Keeping Citizen Scientists in the Dark

    NASA Astrophysics Data System (ADS)

    Ross, R. J.

    2012-08-01

    Las Cumbres Observatory Global Telescope Network (LCOGT) is creating a network of telescopes at excellent sites around the world providing 24/7 all sky coverage for astronomical observations. The network of telescopes, ranging in size from 0.4 m to 2.0 m, will be available for both scientific and education users. The LCOGT telescopes are being built quickly and will be deployed soon. The two 2.0 m Faulkes Telescopes, one on Haleakala, Maui (FTN), the other at Siding Spring Observatory, Australia (FTS), are currently in operation. There is also a 0.8 m telescope in the Santa Ynez Valley, California (BOS), which is being used for commissioning and for many local outreach programs. The first 1.0 m telescopes will be heading to Chile and South Africa in 2011 and will each be accompanied by a 0.4 m telescope. Other sites, including Tenerife (Canary Islands, Spain), McDonald Observatory (Texas), Siding Spring (Australia), and Haleakala (Hawaii) will follow, with the possibility of up to two additional sites yet to be selected. The LCOGT education and public outreach effort is transforming into a "Citizen Science" program. Several projects will encompass taking observations through the network, analyzing the data, and sharing the results with other citizen scientists from around the world. The first of these projects, "Agent Exoplanet," will be launched in mid-2011, and will involve analyzing brand-new data to create a light curve of an exoplanet. As the network is not yet complete, this test project will not include actual observing as future ones will. More information about LCOGT and its Citizen Science program can be found online (http://www.lcogt.net). In addition to material to get started in the Citizen Science program, the website also includes resources and content for more hands-on activities using archived data, general astronomy pages, network information, complete access to the public data archive, current news, and recent publications. And don't forget to

  13. The ALMA Telescope Control System

    NASA Astrophysics Data System (ADS)

    Farris, A.; Marson, Ralph; Kern, Jeff

    2005-10-01

    The Atacama Large Millimeter Array (ALMA) is a joint project between North America, Europe and Japan. ALMA is an aperture synthesis radio telescope consisting of 50 12-meter antennas located at an elevation of 5,000 meters in Llano de Chajnantor, Chile. These antennas will operate at frequencies ranging from 31.3 GHz to 950 GHz. The antennas can be moved and placed in different configurations, with baselines between the antennas varying from 150 meters to 20 km. The 50 antennas are supplemented by sixteen additional ones, known as the ALMA Compact Array (ACA): 12 7-meter antennas and 4 12-meter antennas. The ALMA control system will consist of over 70 computers separated by distances of over 20 km. Two aspects of the system are apparent: its distributed nature and its need to accurately synchronize events across many computers separated by large distances. In this paper we describe key features of the architecture of the ALMA Control System, focusing on its properties as a distributed system and on the mechanisms employed to achieve its time synchronization goals. This control system is a distributed system that uses the ALMA Common Software (ACS) as a middleware system layered on top of CORBA. The architecture of the control system extensively employs the component/container model in ACS. In addition, the use of CORBA allows us to employ Java in the higher levels of the control system, leaving C++ to the lower time-critical levels. Python as a scripting language is used by astronomers, to craft standard observing programs, and engineers, in a testing and debugging mode. Key to the concept of an aperture synthesis telescope is a special purpose hardware system known as a correlator, responsible for making various delay model corrections and correlating the signals from the antennas. There are two correlators in ALMA, one for the array of 50 antennas and one for the ACA. This entire system operates under a control system that must synchronize events across the

  14. Teachers in Class

    ERIC Educational Resources Information Center

    Van Galen, Jane

    2008-01-01

    In this article, I argue for a closer read of the daily "class work" of teachers, as posited by Reay, 1998. In developing exploratory class portraits of four teachers who occupy distinctive social positions (two from working-class homes now teaching upper-middle-class children and two from upper-middle-class homes now teaching poor children), I…

  15. Cloud Structures on Neptune Observed with Keck Telescope Adaptive Optics

    NASA Astrophysics Data System (ADS)

    Max, C. E.; Macintosh, B. A.; Gibbard, S. G.; Gavel, D. T.; Roe, H. G.; de Pater, I.; Ghez, A. M.; Acton, D. S.; Lai, O.; Stomski, P.; Wizinowich, P. L.

    2003-01-01

    We report on observations obtained with the adaptive optics system at the 10 m Keck II Telescope during engineering validation and early science observing time for the adaptive optics system. We observed Neptune at near-infrared wavelengths. Angular resolution was 0.05"-0.06", corresponding to a spatial scale of approximately 1000 km at Neptune. We discuss the latitudinal structure of circumferential cloud bands and of compact infrared-bright features seen in the southern hemisphere, as well as their variation with wavelength. We determine the values of I/F (proportional to the ratio of reflected intensity to incident solar flux) in the J and H infrared-wavelength bands, including narrowband filters where there is strong methane absorption. We use the I/F values inside and outside of methane bands to estimate the altitude of clouds responsible for the brightest compact features in the infrared. Our data show that, on two of our four observing dates, the brightest region on Neptune contained highly reflective haze layers located below the tropopause but not deeper than a few bars.

  16. Cosmology with liquid mirror telescopes

    NASA Technical Reports Server (NTRS)

    Hogg, David W.; Gibson, Brad K.; Hickson, Paul

    1993-01-01

    Liquid mirrors provide an exciting means to obtain large optical telescopes for substantially lower costs than conventional technologies. The liquid mirror concept has been demonstrated in the lab with the construction of a diffraction limited 1.5 m mirror. The mirror surface, using liquid mercury, forms a perfect parabolic shape when the mirror cell is rotated at a uniform velocity. A liquid mirror must be able to support a heavy mercury load with minimal flexure and have a fundamental resonant frequency that is as high as possible, to suppress the amplitude of surface waves caused by small vibrations transmitted to the mirror. To minimize the transmission of vibrations to the liquid surface, the entire mirror rests on an air bearing. This necessitates the mirror cell being lightweight, due to the limited load capabilities of the air bearing. The mirror components must also have physical characteristics which minimize the effects of thermal expansion with ambient temperature fluctuations in the observatory. In addition, the 2.7 m mirror construction is designed so that the techniques used may be readily extended to the construction of large mirrors. To attain the goals of a lightweight, rigid mirror, a composite laminant construction was used. The mirror consists of a foam core cut to the desired parabolic shape, with an accuracy of a few mm. An aluminum hub serves as an anchor for the foam and skin, and allows precise centering of the mirror on the air bearing and drive system. Several plys of Kevlar, covered in an epoxy matrix, are then applied to the foam. A final layer of pure epoxy is formed by spin casting. This final layer is parabolic to within a fraction of a mm. An aluminum ring bonded to the circumference of the mirror retains the mercury, and incorporates stainless-steel hard-points for the attachment of balance weights.

  17. DM/LCWFC based adaptive optics system for large aperture telescopes imaging from visible to infrared waveband.

    PubMed

    Sun, Fei; Cao, Zhaoliang; Wang, Yukun; Zhang, Caihua; Zhang, Xingyun; Liu, Yong; Mu, Quanquan; Xuan, Li

    2016-11-28

    Almost all the deformable mirror (DM) based adaptive optics systems (AOSs) used on large aperture telescopes work at the infrared waveband due to the limitation of the number of actuators. To extend the imaging waveband to the visible, we propose a DM and Liquid crystal wavefront corrector (DM/LCWFC) combination AOS. The LCWFC is used to correct the high frequency aberration corresponding to the visible waveband and the aberrations of the infrared are corrected by the DM. The calculated results show that, to a 10 m telescope, DM/LCWFC AOS which contains a 1538 actuators DM and a 404 × 404 pixels LCWFC is equivalent to a DM based AOS with 4057 actuators. It indicates that the DM/LCWFC AOS is possible to work from visible to infrared for larger aperture telescopes. The simulations and laboratory experiment are performed for a 2 m telescope. The experimental results show that, after correction, near diffraction limited resolution USAF target images are obtained at the wavebands of 0.7-0.9 μm, 0.9-1.5 μm and 1.5-1.7 μm respectively. Therefore, the DM/LCWFC AOS may be used to extend imaging waveband of larger aperture telescope to the visible. It is very appropriate for the observation of spatial objects and the scientific research in astronomy.

  18. Desing of a Laser Guide Star System for the Keck II Telescope

    SciTech Connect

    Friedman, H.W.; Erbert, G.V.; Kuklo, T.; Thompson, G.R.; Wong, N.J.; Gavel, D.T.; Salmon, J.T.; Feldman, M.

    1997-09-11

    A laser guide star system similar to that deployed at the Lick Observatory has been designed for the Keck II 10 m telescope on Mauna Kea, Hawaii. The subaperature size on the primary is comparable to that at Lick, and at the same observational wavelength centered about the K band, so that the average power requirements of the laser system are also comparable, at about 20 W. One major difference is that the seeing at Mauna Kea is about a factor of two better than at Lick so that the spot diameter requirements are smaller and this can give rise to reduced back scatter resulting from saturation effects in the sodium layer. To reduce the peak flux in the sodium layer and obtain a smaller spot diameter, the output beam diameter has been increased along with the repetition rate of the laser. As with the Lick laser system, a dye laser is pumped by a series of frequency doubled YAG lasers which are remotely located and coupled to the dye laser on the telescope by optical fibers. The laser system has a full set of beam control optics as well as launch telescope and safety systems. A computer system couples the laser system to the User Interface and Supervisory Control system of the main telescope. The laser system is due to be shipped to Keck during the fall of 1997 where it will be integrated with the telescope at Mauna Kea. The Adaptive Optics and Optics Bench systems will be integrated first and be ready for integration with the laser in the summer of 1998. 1 ref., 8 figs.

  19. The Advanced Technology Large Aperture Space Telescope (ATLAST): Science Drivers and Technology Developments

    NASA Technical Reports Server (NTRS)

    Postman, Marc; Brown, Tom; Sembach, Kenneth; Giavalisco, Mauro; Traub, Wesley; Stapelfeldt, Karl; Calzetti, Daniela; Oegerle, William; Rich, R. Michael; Stahl, H. Phillip; Tumlinson, Jason; Mountain, Matt; Soummer, Remi; Hyde, Tupper

    2011-01-01

    The Advanced Technology Large-Aperture Space Telescope (ATLAST) is a concept for an 8-meter to 16-meter UVOIR space observatory for launch in the 2025-2030 era. ATLAST will allow astronomers to answer fundamental questions at the forefront of modern astrophysics, including "Is there life elsewhere in the Galaxy?" We present a range of science drivers and the resulting performance requirements for ATLAST (8 to 16 milliarcsecond angular resolution, diffraction limited imaging at 0.5 m wavelength, minimum collecting area of 45 square meters, high sensitivity to light wavelengths from 0.1 m to 2.4 m, high stability in wavefront sensing and control). We also discuss the priorities for technology development needed to enable the construction of ATLAST for a cost that is comparable to current generation observatory-class space missions. Keywords: Advanced Technology Large-Aperture Space Telescope (ATLAST); ultraviolet/optical space telescopes; astrophysics; astrobiology; technology development.

  20. A new telescope control system for the Telescopio Nazionale Galileo II: azimuth and elevation axes

    NASA Astrophysics Data System (ADS)

    Ghedina, Adriano; Gonzalez, Manuel; Pérez Ventura, Héctor; Riverol Rodríguez, A. Luis

    2016-07-01

    TNG is a 4m class active optics telescope at the Observatory of Roque de Los Muchachos. In the framework of keeping optimum performances during observation and continuous reliability the telescope control system (TCS) of the TNG is going through a deep upgrade after nearly 20 years of service. The original glass encoders and bulb lamp heads are substituted with modern steel scale drums and scanning units. The obsolete electronic racks and computers for the control loops are replaced with modern and compact commercial drivers with a net improvement in the motors torque ripple. In order to minimize the impact on the number of nights lost during the mechanical and electronic changes in the TCS the new TCS is developed and tested in parallel to the existing one and three steps will be taken to achieve the full upgrade. We describe here the second step that affected the main axes of the telescope, AZ and EL.