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101.
Gordon Chin Scott Brylow Marc Foote James Garvin Justin Kasper John Keller Maxim Litvak Igor Mitrofanov David Paige Keith Raney Mark Robinson Anton Sanin David Smith Harlan Spence Paul Spudis S. Alan Stern Maria Zuber 《Space Science Reviews》2007,129(4):391-419
NASA’s Lunar Precursor Robotic Program (LPRP), formulated in response to the President’s Vision for Space Exploration, will
execute a series of robotic missions that will pave the way for eventual permanent human presence on the Moon. The Lunar Reconnaissance
Orbiter (LRO) is first in this series of LPRP missions, and plans to launch in October of 2008 for at least one year of operation.
LRO will employ six individual instruments to produce accurate maps and high-resolution images of future landing sites, to
assess potential lunar resources, and to characterize the radiation environment. LRO will also test the feasibility of one
advanced technology demonstration package. The LRO payload includes: Lunar Orbiter Laser Altimeter (LOLA) which will determine
the global topography of the lunar surface at high resolution, measure landing site slopes, surface roughness, and search
for possible polar surface ice in shadowed regions, Lunar Reconnaissance Orbiter Camera (LROC) which will acquire targeted
narrow angle images of the lunar surface capable of resolving meter-scale features to support landing site selection, as well
as wide-angle images to characterize polar illumination conditions and to identify potential resources, Lunar Exploration
Neutron Detector (LEND) which will map the flux of neutrons from the lunar surface to search for evidence of water ice, and
will provide space radiation environment measurements that may be useful for future human exploration, Diviner Lunar Radiometer
Experiment (DLRE) which will chart the temperature of the entire lunar surface at approximately 300 meter horizontal resolution
to identify cold-traps and potential ice deposits, Lyman-Alpha Mapping Project (LAMP) which will map the entire lunar surface
in the far ultraviolet. LAMP will search for surface ice and frost in the polar regions and provide images of permanently
shadowed regions illuminated only by starlight. Cosmic Ray Telescope for the Effects of Radiation (CRaTER), which will investigate
the effect of galactic cosmic rays on tissue-equivalent plastics as a constraint on models of biological response to background
space radiation. The technology demonstration is an advanced radar (mini-RF) that will demonstrate X- and S-band radar imaging
and interferometry using light weight synthetic aperture radar. This paper will give an introduction to each of these instruments
and an overview of their objectives. 相似文献
102.
Donald L. Hampton James W. Baer Martin A. Huisjen Chris C. Varner Alan Delamere Dennis D. Wellnitz Michael F. A’Hearn Kenneth P. Klaasen 《Space Science Reviews》2005,117(1-2):43-93
A suite of three optical instruments has been developed to observe Comet 9P/Tempel 1, the impact of a dedicated impactor spacecraft,
and the resulting crater formation for the Deep Impact mission. The high-resolution instrument (HRI) consists of an f/35 telescope with 10.5 m focal length, and a combined filtered CCD camera and IR spectrometer. The medium-resolution instrument
(MRI) consists of an f/17.5 telescope with a 2.1 m focal length feeding a filtered CCD camera. The HRI and MRI are mounted on an instrument platform
on the flyby spacecraft, along with the spacecraft star trackers and inertial reference unit. The third instrument is a simple
unfiltered CCD camera with the same telescope as MRI, mounted within the impactor spacecraft. All three instruments use a
Fairchild split-frame-transfer CCD with 1,024× 1,024 active pixels. The IR spectrometer is a two-prism (CaF2 and ZnSe) imaging spectrometer imaged on a Rockwell HAWAII-1R HgCdTe MWIR array. The CCDs and IR FPA are read out and digitized
to 14 bits by a set of dedicated instrument electronics, one set per instrument. Each electronics box is controlled by a radiation-hard
TSC695F microprocessor. Software running on the microprocessor executes imaging commands from a sequence engine on the spacecraft.
Commands and telemetry are transmitted via a MIL-STD-1553 interface, while image data are transmitted to the spacecraft via a low-voltage differential signaling (LVDS) interface standard. The instruments are used as the science instruments and are
used for the optical navigation of both spacecraft. This paper presents an overview of the instrument suite designs, functionality,
calibration and operational considerations. 相似文献
103.
de Jager C. Hartle James B. Drawin H. W. Giovanelli R. G. Freudenthal Hans Wittenberg H. Tobias Cornelius A. Van Der Laan H. Smit J. A. 《Space Science Reviews》1974,15(5):741-746
Space Science Reviews - 相似文献
104.
Scientists and educators at Baylor College of Medicine are using space life sciences research areas as themes for middle school science and health instructional materials. This paper discusses study findings of the most recent unit, Food and Fitness, which teaches concepts related to energy and nutrition through guided inquiry. Results of a field test involving more than 750 students are reported. Use of the teaching materials resulted in significant knowledge gains by students as measured on a pre/post assessment administered by teachers. In addition, an analysis of the time spent by each teacher on each activity suggested that it is preferable to conduct all of the activities in the unit with students rather than allocating the same total amount of time on just a subset of the activities. 相似文献
105.
Fucci RL Gardner J Hanifin JP Jasser S Byrne B Gerner E Rollag M Brainard GC 《Acta Astronautica》2005,56(9-12):1017-1024
Light is being used as a pre-launch countermeasure to circadian and sleep disruption in astronauts. The effect of light on the circadian system is readily monitored by measurement of plasma melatonin. Our group has established an action spectrum for human melatonin regulation and determined the region of 446-477 nm to be the most potent for suppressing plasma melatonin. The aim of this study was to compare the efficacy of 460 and 555 nm for suppressing melatonin using a within-subjects design. Subjects (N=12) were exposed to equal photon densities (7.18 x 10(12) photons/cm2/s) at 460 and 555 nm. Melatonin suppression was significantly stronger at 460 nm (p<0.02). An extension to the action spectrum showed that 420 nm light at 16 and 32 microW/cm2 significantly suppressed melatonin (p<0.04 and p<0.002). These studies will help optimize lighting countermeasures to circadian and sleep disruption during spaceflight. 相似文献
106.
James L. Rand 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(1):5-8
An abnormally large number of catastrophic failures have occurred in recent years which have prompted a number of investigations. This paper documents the efforts by Winzen engineers to determine the cause of these dangerous failures. It is concluded that catastrophic failure will occur if internal caps separate from the wall of the balloon at too low an altitude. Cap separation may be prevented by the use of external caps. 相似文献
107.
H.G. James 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1981,1(2):241-244
WISP/HF is the medium- and high-frequency part of the Waves-In-Space-Plasmas facility. It is a flexible Shuttle/Spacelab instrument for transmitting, receiving and processing signals in the 0.3 to 30 MHz range. WISP/HF will be used to study the transmitting antenna, fundamentals of electromagnetic (EM) and electrostatic (ES) waves in magnetoplasmas, plasma instabilities and nonlinearities, and sounding of ionospheric structure. 相似文献
108.
We are on the verge of a new era of commercial and industrial expansion in space that will have a major impact on America's future and on the future of the world. It is a turning point that will set the US national agenda in space well into the 21st century, and, as such, will have an important impact on space-related activities worldwide. The USA is now gearing up to face the challenges of this new era. James Beggs, NASA Administrator, describes the US space station programme. 相似文献
109.
Garry E. Hunt Philip B. James 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1985,5(8):93-99
In this paper we summarise the current understanding of Martian condensate and dust clouds. The paper is particularly concerned with the spatial, temporal and seasonal characteristics of the clouds. The condensate clouds are composed of water and ice particles and occasionally CO2 particles. Dust clouds are composed of material from the surface and redistributed over the planet through the weather systems. The apparent lack of annual reproductivity of these dust storms forms a major unresolved problem. We discuss in this paper the types of observations needed in future space missions, in particular the requirements for the NASA Mars Geochemical Climatology Orbiter Mission planned for the end of this decade. 相似文献
110.
James M. Rosen 《Space Science Reviews》1969,9(1):58-89
A review of measurements sensitive to dust in the stratosphere is presented with special emphasis on the data obtained during the last 10 years. The measurements made by indirect techniques such as light scattering tend to show more stratospheric dust than the measurements obtained by direct sampling techniques, although this interpretation is somewhat complicated by the injection of dust from the Bali eruption in 1963. The discrepancy is interpreted as indicating that the stratospheric dust smaller than a few microns diameter is volital. Recent direct experimental evidence of the author supports this conclusion.The size distribution of stratospheric dust is presented as a composite of the results of several observers. A natural break in the distribution at a size of about 5 diameter is interpreted as indicating that the smaller dust is terrestrial in origin, while the larger dust is meteoric in origin. Other evidence is presented to support this conclusion. A comparison with particle flux measurements at 100 km and higher indicates that the meteoric component of the stratospheric dust is ablation products rather than single particles that have survived entry into the atmosphere. It is also argued that the small particles accounting for the high flux as measured by rocket and satellite microphone techniques are not present in the stratosphere. 相似文献