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Notes on Soviet space astronomy

Soviet space programs intended for making astronomical observations are reviewed. The Cosmos, Intercosmos, and Prognoz satellites designed for astronomical measurements are identified, and unmanned lunar and planetary missions are discussed, including the Luna, Lunokhod, Mars, and Venera programs. The Salyut 4 space station is described in detail along with the following major astronomical instruments: the Orbiting Solar Telescope 1, the infrared telescope spectrometer, the two solar spectrometers, the light-nuclei mass spectrometer, and the Filin and RT-4 X-ray telescopes. The future of Soviet space astronomy is assessed, particularly the tasks of the Salyut 5 station and the scheduled launch of Salyut 6.

Oberg, J. E.↗

Auger spectroscopic examination of MgF2-coated Al mirrors before and after UV irradiation

Magnesium fluoride protected Al films were studied since these mirrors are commonly used in astronomical instruments whenever a highly reflecting optical surface is required in the wavelength region from 1100 A to 2000 A. Freshly prepared samples of evaporated Al + 250-A thick MgF2 on glass were analyzed by Auger electron spectroscopy in conjunction with surface erosion by Ar(+) ion bombardment before and after UV irradiation. The analysis showed that a very thin layer of surface contamination and not bulk photolysis in the MgF2 film was reponsible for the irradiation-induced reflectance loss. Postirradiation polishing with a mild calcium carbonate abrasive can restore a mirror's reflectance by removing the photolyzed surface film without disturbing the MgF2 layer.

Heaney, J. B.↗

Large multi-lensed telescope - A receiver for point sources in the sky

A large 80-in. (2-meter) multilensed computer-controlled and encoder-pointed telescope is described. It is being used as the receiver in the high-performance lunar laser ranging station on Mt. Haleakala on the island of Maui, Hawaii; however, it could also be used for other astronomical applications when the moon is not up. This telescope, which was designed for applications requiring aperture but not field, could affect the design of future very large astronomical instruments intended mainly for point-source spectroscopy and similar applications. The telescope and its performance to date are discussed.

Faller, J. E.↗

Investigation of small solar system objects with the space telescope

The application of the space telescope (ST) to study small objects in the solar system in order to understand the birth and the early evolution of the solar system is discussed. The upper size limit of the small bodies is defined as approximately 5000 km and includes planetary satellites, planetary rings, asteroids, and comets.The use of the astronomical instruments aboard the ST, such as the faint object camera, ultraviolet and infrared spectrometers, and spectrophotometers, to study the small solar system objects is discussed.

Morrison, D.↗

MOSAIC

The Mosaicked Optical Self-scanned Array Imaging Camera (MOSAIC), is a 50 sq cm active area detector system encompassing 5.76 million picture elements. This camera is being developed for use in astronomical instrumentation requiring the use of large area imaging detectors with high resolution photon counting capability in the space ultraviolet. This paper gives a descriptive outline of the MOSAIC camera system including: the 100 mm diameter microchannel plate intensifier, the 3 x 3 array of 800 x 800 pixel charge coupled devices, the signal processing and buffer storage subsystem, the electronic support and control subsystem, and the data processing subsystem. Performance characteristics of the camera and its subsystems are presented, based on system analysis.

Williams, J. T.↗

World Atlas of large optical telescopes (second edition)

By early 1986 there will be over 120 large optical telescopes in the world engaged in astronomical research with mirror or lens diameters of one meter (39-inches) and larger. This atlas gives information on these telescopes and shows their observatory sites on continent sized maps. Also shown are observatory locations considered suitable for the construction of future large telescopes. Of the 126 major telescopes listed in this atlas, 101 are situated in the Northern Hemisphere and 25 are located in the Southern Hemisphere. The totals by regions are as follows: Europe (excluding the USSR), 30; Soviet Union, 9; Asia (excluding the USSR), 5; Africa, 9; Australia, 6; The Pacific, 4 (all on Hawaii); South America, 17; North America, 46 (the continental US has 38 of these). In all, the United States has 42 of the world's major telescopes on its territory (continental US plus Hawaii) making it by far the leading nation in astronomical instrumentation.

Meszaros, S. P.↗

Imaging front-end systems for millimeter waves and submillimeter waves

Imaging (multi-beam) front-end systems utilize a reflector or a lens, as well as a focal-plane array of receptor elements (beams). To be practical, such systems must utilize focal plane arrays which can be fabricated using hybrid integrated (and eventually monolithic) technology. This paper reviews alternative approaches to focussing elements, auxiliary devices required for local oscillator injection and similar functions, and focal plane arrays. It also discusses general limitations and advantages of these approaches, as well as typical applications to millimeter and submillimeter astronomical instrumentation.

Yngvesson, K. S.↗

Hubble Space Telescope satellite

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.

Mitchell, R. E.↗

Large deployable reflector thermal characteristics in low earth orbits

Preliminary results are presented from the development of a thermal analytical tool capable of analyzing the orbital thermal characteristics of a Large Deployable Reflector (LDR) spaceborne astronomical instrument for observations in the 30-micron to 1-mm range. This LDR thermal analytical tool is a 9X6-node reflector thermal model to be used in conjunction with the thermal analyzer program SINDA, as well as the orbital heat flux program TRASYS for the computation of solar and IR radiation and orbit-related input data.

Wu, Y. C.↗

Grazing incidence reflectance of SiC films produced by plasma-assisted chemical vapor deposition

The grazing incidence reflectance of silicon carbide films produced by plasma-assisted chemical vapor deposition has been evaluated in the spectral region from 256 to 1216 A. The results show that reflectivities higher than conventional coatings can be obtained on coatings deposited both on silicon wafers and quartz substrates. Potential application of silicon carbide films for EUV astronomical instruments will be discussed.

Keski-Kuha, Ritva A. M.↗

Panel on Space Station utilization benefits

An account is given of recent changes in the NASA Space Station, under the guidance of updated user community payload requirements. The user communities are those of astronomy, the life sciences, earth observation, and international applications. Attention is given to the resolutions that will be achievable by astronomical instruments aboard the Space Station, the testing of prototype earth observation instruments aboard the Station's manned module, and the microgravity research efforts planned in conjunction with ESA.

Rubenstein, Sy Z.↗

MERI: An ultra-long-baseline Moon-Earth radio interferometer

An extension of the very long baseline technique currently used with ground based telescopes which will produce a resolution of 0.4 micro-arcsec at 300 GHz is described. The MERI array will open an entirely new regime of wavelengths, resolutions, and sensitivities for radio astronomy. As with any such leap in astronomical instrumentation, this advancement will result in the observation of a variety of known radio sources and the exploration of their structures in unprecedented detail. Even so, it may be the serendipitous discoveries, which are by definition impossible to predict, that ultimately justify the construction of MERI.

Burns, Jack O.↗

Blocked impurity band hybrid infrared focal plane arrays for astronomy

High-performance infrared hybrid focal plane arrays using 10- x 50-element Si:As blocked-impurity-band (BIB) detectors (cutoff wavelength = 28 microns) and matching switched MOSFET multiplexers have been developed and characterized for space astronomy. Use of impurity-band-conduction technology provides detectors which are nuclear-radiation-hard and free of the many anomalies associated with conventional silicon photoconductive detectors. Emphasis in the present work is on recent advances in detector material quality which have led to significantly improved detector and hybrid characteristics. Results demonstrating increased quantum efficiency (particularly at short-wavelength infrared), obtained by varying the BIB detector properties (infrared active layer thickness and arsenic doping profile), are summarized. Measured read noise and dark current for different temperatures are reported. The hybrid array performance achieved demonstrates that BIB detectors are well suited for use in astronomical instrumentation.

Reynolds, D. B.↗

Astrophysics from the moon

Preliminary studies have been conducted for the concept of a lunar base supporting astronomical instruments of power comparable to the VLA, giving attention to aperture-synthesis arrays which could improve angular resolution to the level of a few microarcsec. The only conceivable mode of catastrophic instrument failure envisioned would be a meteorite strike, although the probability for this is small and comparable to that encountered in orbital instruments. Nevertheless, lunar dust may pose problems, lunar soil may be inadequate for support of instrument structures, moonquakes may disturb instruments, gravitational deflection may distort them, and heat radiation and scattered light may exert troublesome influences on observations. Representative parameters for a specific system are presented.

Burke, Bernard F.↗

Explosive Transient Camera (ETC) Program

Since the inception of the ETC program, a wide range of new technologies was developed to support this astronomical instrument. The prototype unit was installed at ETC Site 1. The first partially automated observations were made and some major renovations were later added to the ETC hardware. The ETC was outfitted with new thermoelectrically-cooled CCD cameras and a sophisticated vacuum manifold, which, together, made the ETC a much more reliable unit than the prototype. The ETC instrumentation and building were placed under full computer control, allowing the ETC to operate as an automated, autonomous instrument with virtually no human intervention necessary. The first fully-automated operation of the ETC was performed, during which the ETC monitored the error region of the repeating soft gamma-ray burster SGR 1806-21.

Ricker, George↗

Hybrid silicon focal plane arrays

Applications were demonstrated for hybrid silicon infrared CCD arrays in both ground and space based astronomical instrumentation. The primary goal was to provide a point of departure for both instrument designs and further development of the device. The test device is an indium doped silicon (Si:In) version of the 32 x 32 Rockwell 30331 surface channel hybrid silicon IRCCD. The device structure and a typical instrument interface are shown. The motivation for further study is presented along with a discussion in detail of some of the issues.

Pommerrenig, D.↗

Project TIMS (Teaching Integrated Math/Science)

The goal of this project is to increase the scientific knowledge and appreciation bases and skills of pre-service and in-service middle school teachers, so as to impact positively on teaching, learning, and student retention. This report lists the objectives and summarizes the progress thus far. Included is the working draft of the TIMS (Teaching Integrated Math/Science) curriculum outline. Seven of the eight instructional subject-oriented modules are also included. The modules include informative materials and corresponding questions and educational activities in a textbook format. The subjects included here are the universe and stars; the sun and its place in the universe; our solar system; astronomical instruments and scientific measurements; the moon and eclipses; the earth's atmosphere: its nature and composition; and the earth: directions, time, and seasons. The module not included regards winds and circulation.

Edwards, Leo, Jr.↗

The Second Annual International Space University Alumni Conference

The papers presented at the conference reflect the multidisciplinary nature of the International Space University (ISU) and its alumni. The first papers presented hold special relevance to the design projects, and cover such topics as lunar-based astronomical instrumentation, solar lunar power generation, habitation on the moon, and the legal issues governing multinational astronauts conducting research in space. The next set of papers cover various technical issues such as project success assessment, satellite networks and space station dynamics, thus reflecting the diverse backgrounds of the ISU alumni.

Johnson, Les↗