The Experts below are selected from a list of 270 Experts worldwide ranked by ideXlab platform
Paul D. Spudis - One of the best experts on this subject based on the ideXlab platform.
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Illumination conditions of the South Pole of the Moon derived using Kaguya topography
Icarus, 2010Co-Authors: D. B. J. Bussey, Paul D. Spudis, J. A. Mcgovern, Catherine D. Neish, Hirotomo Noda, Yoshiaki Ishihara, S. A. SorensenAbstract:Abstract We have used the Kaguya laser altimeter-derived topography to conduct a comprehensive study of the illumination conditions at the Moon’s South Pole. We have determined, by comparing simulated and actual Clementine images, that the Kaguya topography can be used to generate realistic illumination conditions. We generated an average illumination map for the year 2020 for the lunar South Pole region. From this we identified the areas that receive the most illumination. The place receiving the most illumination (86% of the year) is located close to the rim of Shackleton crater at 88.74°S 124.5°E. However two other areas, less than 10 km apart from each other, are collectively lit for 94% of the year. We found that sites exist near the South Pole that are continuously lit for several months during summer. We were also able to map the locations and durations of eclipse periods for these areas. Finally we analyzed the seasonal variations in lighting conditions, from summer to winter, for key areas near the South Pole. We conclude that areas exist near the South Pole that have illumination conditions that make them ideal candidates as future outpost sites.
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THE GEOLOGY OF THE South Pole OF THE MOON AND AGE OF SHACKLETON CRATER. Paul
2008Co-Authors: Paul D. Spudis, J Plescia, D. B. J. Bussey, J. L. Josset, S BeauvivreAbstract:The South Pole of the Moon is located in the rugged, heavily cratered terrain of the Southern highlands [1]. Because the lunar spin axis is oriented about 1.5o from a normal to the ecliptic, sunlight is always at low incidence at the Poles, creating both a unique environment and some difficulty in geological interpretation of the region. Newly obtained radar images of the lunar South Pole permit us to observe several areas of this region that are in permanent sun shadow [2]. Together with earlier data for the Poles from the orbital Clementine and Lunar Prospector missions [3-5], we now have an abundance of information on the geology and environment of the South Pole.
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Geology of Shackleton Crater and the South Pole of the Moon
Geophysical Research Letters, 2008Co-Authors: Paul D. Spudis, Ben Bussey, Jean Luc Joset, J Plescia, S BeauvivreAbstract:Using new SMART-1 AMIE images and Arecibo and Goldstone high resolution radar images of the Moon, we investigate the geological relations of the South Pole, including the 20 km-diameter crater Shackleton. The South Pole is located inside the topographic rim of the South Pole- Aitken (SPA) basin, the largest and oldest impact crater on the Moon and Shackleton is located on the edge of an interior basin massif. The crater Shackleton is found to be older than the mare surface of the Apollo 15 landing site (3.3 Ga), but younger than the Apollo 14 landing site (3.85 Ga). These results suggest that Shackleton may have collected extra-lunar volatile elements for at least the last 2 billion years and is an attractive site for permanent human presence on the Moon.
S Beauvivre - One of the best experts on this subject based on the ideXlab platform.
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THE GEOLOGY OF THE South Pole OF THE MOON AND AGE OF SHACKLETON CRATER. Paul
2008Co-Authors: Paul D. Spudis, J Plescia, D. B. J. Bussey, J. L. Josset, S BeauvivreAbstract:The South Pole of the Moon is located in the rugged, heavily cratered terrain of the Southern highlands [1]. Because the lunar spin axis is oriented about 1.5o from a normal to the ecliptic, sunlight is always at low incidence at the Poles, creating both a unique environment and some difficulty in geological interpretation of the region. Newly obtained radar images of the lunar South Pole permit us to observe several areas of this region that are in permanent sun shadow [2]. Together with earlier data for the Poles from the orbital Clementine and Lunar Prospector missions [3-5], we now have an abundance of information on the geology and environment of the South Pole.
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Geology of Shackleton Crater and the South Pole of the Moon
Geophysical Research Letters, 2008Co-Authors: Paul D. Spudis, Ben Bussey, Jean Luc Joset, J Plescia, S BeauvivreAbstract:Using new SMART-1 AMIE images and Arecibo and Goldstone high resolution radar images of the Moon, we investigate the geological relations of the South Pole, including the 20 km-diameter crater Shackleton. The South Pole is located inside the topographic rim of the South Pole- Aitken (SPA) basin, the largest and oldest impact crater on the Moon and Shackleton is located on the edge of an interior basin massif. The crater Shackleton is found to be older than the mare surface of the Apollo 15 landing site (3.3 Ga), but younger than the Apollo 14 landing site (3.85 Ga). These results suggest that Shackleton may have collected extra-lunar volatile elements for at least the last 2 billion years and is an attractive site for permanent human presence on the Moon.
Mark Hereld - One of the best experts on this subject based on the ideXlab platform.
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THE South Pole NEAR INFRARED SKY BRIGHTNESS
Publications of the Astronomical Society of the Pacific, 1996Co-Authors: H. T. Nguyen, Doyal A. Harper, Mark Hereld, Bernard J. Rauscher, Scott A. Severson, R. F. Lowenstein, F. Morozek, Robert J. PernicAbstract:We report our finding that the South Pole is the darkest known Earth-based site for near infrared astronomical observations. For this reason it has great potentail for the most sensitive surveys of distant or faint objects. We find that the South polar sky background is substantially darker in the standard near infrared J, H, and K filters, and in an optimized KDARK filter centered at 2.36 microns. In particular, the KDARK background at the South Pole is only 162 ± 67 mu-Jy arcsec-2 at the zenith. This is consistent with the results described in an accompanying paper by Ashley et al. 1996, and is comparable to the sky brightness measured by high altitude balloon in the 2.4 micron (Matsumoto et al. 1994).
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SPIREX — Near Infrared Astronomy from the South Pole
Experimental Astronomy, 1994Co-Authors: Mark HereldAbstract:Over the next several years we will deploy a series of spectrometers, imagers, and telescopes at the South Pole as part of a project named SPIREX-for South Pole Infrared Explorer. Our goal is to survey a substantial area of the sky to study the origins of galaxies and stars.
John W. V. Storey - One of the best experts on this subject based on the ideXlab platform.
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Operation of the Near Infrared Sky Monitor at the South Pole
Publications of the Astronomical Society of Australia, 2002Co-Authors: Jon Lawrence, Michael C. B. Ashley, R. J. Pernic, Michael G. Burton, Paolo G. Calisse, J. R. Everett, A. Phillips, John W. V. StoreyAbstract:The near infrared sky spectral brightness has been measured at the South Pole with the Near Infrared Sky Monitor (NISM) throughout the 2001 winter season. The sky is found to be typically more than an order of magnitude darker than at temperate latitude sites, consistent with previous South Pole observations. Reliable robotic operation of the NISM, a low power, autonomous instrument, has been demonstrated throughout the Antarctic winter. Data analysis yields a median winter value of the 2.4 µm (Kdark) sky spectral brightness of ∼120 µJy arcsec −2 and an average of 210 ± 80 µJy arcsec −2 . The 75%, 50%, and 25% quartile values are 270 ± 100, 155 ± 60, and 80 ± 30 µJy arcsec −2 , respectively.
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ABU/SPIREX: South Pole thermal IR experiment
Infrared Astronomical Instrumentation, 1998Co-Authors: Albert M. Fowler, Nigel Sharp, William J. Ball, Antony Schinckel, Michael C. B. Ashley, Maxime Boccas, John W. V. Storey, Darren L. Depoy, Paul Martini, Doyal A. HarperAbstract:ABU is a NOAO IR imaging camera designed for evaluating the performance of the 1024x1024 Aladdth InSb array. For this experiment, it was outfitted with five filters (see Figure 9) m the 3-5 micron range to exploit the low water vapor and lower air temperatures at the South Pole. At the South Pole it was integrated with the CARA SPIREX (South Pole Infrared Explorer) telescope. Figure 1 is a picture of the telescope showing the environmental box (the white box by the author). which protected ABU and its electronics from ambient environmental conditions.
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Site Conditions for Astronomy at the South Pole
Infrared Astronomical Instrumentation, 1998Co-Authors: John W. V. Storey, Michael C. B. Ashley, Michael G. Burton, M. A. PhillipsAbstract:We discuss the site conditions for astronomy at the South Pole and over the Antarctic plateau. We find that these conditions are the most favorable on Earth for sensitive observations at thermal IR and sub-millimeter wavelengths. We further discuss plans to develop IR facilities to exploit this potential.
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Near-infrared sky brightness monitor for the South Pole
Infrared Technology XXI, 1995Co-Authors: Michael C. B. Ashley, Michael G. Burton, James P. Lloyd, John W. V. StoreyAbstract:ABSTRACT The antarctic plateau has the potential for being the best site on Earth for conducting astronomical observationsfrom the near-infrared to the sub-millimeter. Particular gains are expected in the 1 to 5micron region, wherethe high altitude, low water vapour content, and low thermal emission from the atmosphere combine to createobserving conditions unequalled elsewhere on the surface of the earth. We describe an instrument, the InfraredPhotometer-Spectrometer (IRPS), that we are using to quantify site conditions at the South Pole by measuring thenear-infrared sky brightness. We also describe some ofthe unique problems associated with building instrumentsto work in Antarctica.Keywords: near-infrared, Antarctica, astronomy, site-testing 1 THE ENVIRONMENT AT THE South Pole The US Amundsen-Scott South Pole Station is located within a few hundred meters of the Geodetic SouthPole, at an altitude of 2900 m. Centrifugal and temperature effects reduce the air-pressure to the equivalent ofbetween 3200 and 3600 m depending on the weather. At these altitudes, there is noticeably less oxygen in the air,leading to sleeping difficulties, reduced mental capacity, loss-of-breath after moderate exercise, and sometimes
J. C. Ehramjian - One of the best experts on this subject based on the ideXlab platform.
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Comparison of UV climates at Summit, Greenland; Barrow, Alaska and South Pole, Antarctica
Atmospheric Chemistry and Physics Discussions, 2008Co-Authors: G. Bernhard, C. R. Booth, J. C. EhramjianAbstract:An SUV-150B spectroradiometer for measuring solar ultraviolet (UV) irradiance was installed at Summit, Greenland, in August 2004. Here we compare the initial data from this new location with similar measurements from Barrow, Alaska and South Pole. Measurements of irradiance at 345 nm performed at equivalent solar zenith angles (SZAs) are almost identical at Summit and South Pole. The good agreement can be explained with the similar location of the two sites on high-altitude ice caps with high surface albedo. Clouds have little impact at both sites, but can reduce irradiance at Barrow by more than 75%. Clear-sky measurements at Barrow are smaller than at Summit by 14% in spring and 36% in summer, mostly due to differences in surface albedo and altitude. Comparisons with model calculations indicate that aerosols can reduce clear-sky irradiance at 345 nm by 4?6%; aerosol influence is largest in April. Differences in total ozone at the three sites have a large influence on the UV Index. At South Pole, the UV Index is on average 20?80% larger during the ozone hole period than between January and March. At Summit, total ozone peaks in April and UV Indices in spring are on average 10?25% smaller than in the summer. Maximum UV Indices ever observed at Summit and South Pole are 6.7 and 4.0, respectively. The larger value at Summit is due to the site's lower latitude. For comparable SZAs, average UV Indices measured during October and November at South Pole are 1.9?2.4 times larger than measurements during March and April at Summit. Average UV Indices at Summit are over 50% greater than at Barrow because of the larger cloud influence at Barrow.
