|
|
Physics
Prospero 8/12/2008 | 0 (0) | 56 | 0 | 0 | English
Foing, Racca, Grande, Huovelin, Josset, Keller, Nathues, Malkki, Heather, Koschny, Almeida, Frew, Lumb, Volp, Zender (SMART-1 Science & Technology Working Team), SMART-1 Project ESTEC/SCI-PD, Noordwijk, Nederland -
SMART-1 is the first in the program of ESA’s Small Missions for Advanced Research and Technology. Its first objective has been achieved to demonstrate Solar Electric Primary Propulsion (SEP) for future Cornerstones (such as Bepi-Colombo) and to test new technologies for spacecraft and instruments. The spacecraft has been launched on 27 Sept. 2003, as an Ariane-5 auxiliary passenger and injected in GTO Geostationary Tranfer Orbit. Thanks to the successful electric propulsion navigation, the spacecraft has left the inner radiation belts in early 2004, and reached lunar capture on 17 November 2004. ... more>>
Prospero 8/12/2008 | 0 (0) | 41 | 0 | 0 | English
E. Asphaug, C. Agnor and Q. Williams, Center for Origin, Dynamics & Evolution of Planets, Earth Sciences Dept. University of California, Santa Cruz - Impacts, Shocks & Tides: Planetary collisions are usually understood as shock-related phenomena, analogous to impact cratering. But at large scales, where the impact timescale is comparable to the gravitational timescale, collisions can be dominated by gravitational torques and disruptive tides. ... more>>
Prospero 8/12/2008 | 0 (0) | 52 | 0 | 0 | English
Farquhar and Wing, Earth System Science Interdisciplinary Center and Department of Geology, University of Maryland, College Park.
We are measuring sulfur multiple iso-tope abundances in 10 lunar basalts, a suite of terrestrial igneous rocks, and samples of Canon Diablo Troilite (CDT). Ongoing measurements suggest that the acid volatile sulfur (AVS) in lunar basalts is only slightly enriched in 34S relative to CDT, confirming earlier results. High-precision sulfur multiple isotope measurements also indicate that lunar AVS falls on a fractionation line defined by the bulk com-position of CDT and a slope of 0.515. ... more>>
Prospero 8/12/2008 | 0 (0) | 43 | 0 | 0 | English
Holsclaw, McClintock, Robinson, Laboratory for Atmospheric and Space Physics, Boulder, CO, Northwestern University, Evanston .
The Mercury Atmospheric and Surface Composition Spectrometer (MASCS) is one of seven science instruments onboard NASA’s MESSENGER mission, currently en-route to the planet Mercury. One of MASCS’s components, referred to as the Visible and Near Infrared Spectrograph (VIRS), will record reflectance spectra of the surface in order to characterize the mineralogy of the planet. The lunar highlands and the average mercurian crust are proposed to be compositionally similar. In preparation to interpret VIRS reflectance spectra of Mercury to be first obtained in 2008, the Moon has been observed with an engineering model of the VIRS from a ground-based telescope. In this study, the ultraviolet and visible region of the spectrum is compared with titanium content in the lunar regolith. ... more>>
Prospero 8/12/2008 | 0 (0) | 49 | 0 | 0 | English
Elphic, Lawrence, Feldman, Prettyman, Maurice, Bussey, Spudis and Lucey, Space and Atmospheric Sciences, Los Alamos National Laboratory & 2Centre d'Etude Spatiale des Rayonnements (CESR),Toulouse, France, Johns Hopkins Applied Physics Laboratory, Laurel, MD, Hawai’i Institute of Geophysics and Planetology, University of Hawai’i, Honolulu. - Introduction: Reservoirs of volatiles cold-trapped in permanent shadow at the lunar poles are scientifically valuable and a potential in situ resource for exploration. ... more>>
Prospero 8/12/2008 | 0 (0) | 45 | 0 | 0 | English
B. B. Wilcox, P. G. Lucey and J. T. Cahill, Hawaii Institute of Geophysics and Planetology, University of Hawaii. - Space weathering processes on the Moon control the production of the regolith and the alteration of its optical properties. Larger impacts produce new regolith from bedrock and smaller impacts work to comminute it to finer particle sizes. Solar wind sputtering and micrometeorite impact vaporization combine to cause regolith spectra to both redden and darken. Two data sets exist that are sensitive to these two processes. Thermal images of the Moon, taken during eclipse, are sensitive to the particle size distribution of the surface (the amount of rocks). Optical Maturity (OMAT) parameter images, on the other hand, are sensitive to the amount of agglutinates and nanophase iron produced as a result of surface exposure to space weathering processes. Analysis of these images offer new insights into the state of the lunar regolith and its evolution. ... more>>
Prospero 8/12/2008 | 0 (0) | 46 | 0 | 0 | English
Miura, Dept. Earth Sci., Fac. Sci., Yamaguchi University, Yamaguchi, Japan. - Impact crater on the Moon is defined by typical impact process on the highland. Mare basalt is filled to wide impact crater structure only front side of the Moon, mainly by large impact or tidal forces from Earth. The main purpose of this paper is 1) to elucidate large lunar craters with volcanic rocks compared with terrestrial crater, 2) to classify craters with volacin rocks on Earth. ... more>>
Prospero 8/12/2008 | 0 (0) | 94 | 0 | 0 | English
Stubbs, Vondrak and Farrell, NASA Goddard, Greenbelt. - From the Apollo era it is known that dust on the Moon can cause serious problems for exploration activities. Such problems include adhering to clothing and equipment, reducing external visibility on landings, and causing difficulty to breathing and vision within the spacecraft. An important step in dealing with dust-related problems is to understand how dust grains behave in the lunar environment. Past Experiences. All astronauts who walked on the Moon reported difficulties with lunar dust. Eugene Cernan, commander of Apollo 17, stated that “… one of the most aggravating, restricting facets of lunar surface exploration is the dust and its adherence to everything no matter what kind of material, whether it be skin, suit material, metal, no matter what it be and it’s restrictive friction-like action to everything it gets on." Highest Future Priority. Dust has also been highlighted as a priority by the Mars Exploration Program Assessment Group (MEPAG): “1A. Characterize both aeolian dust and particulates that woould be kicked up from the martian regolith by surface operations of a human mission with fidelity sufficient to establish credible engineering simulation labs and/or software codes on Earth.” We shall briefly describe the properties of lunar dust and its impact on the Apollo astronauts, and then summarize three main problems areas for understanding its behavior: Dust Adhesion and Abrasion, Surface Electric Fields and Dust Transport. These issues are all inter-related and must be well understood in order to minimize the impact of dust on lunar surface exploration. ... more>>
Prospero 8/12/2008 | 0 (0) | 47 | 0 | 0 | English
Kramer, Jolliff, Neal, Kirkland and Fessler University of Notre Dame, Department of Civil Engineering and Geological Sciences & Washington University, Department of Earth and Planetary Sciences; Lunar and Planetary Institute, Houston. - Some of the (Apollo 14) high-Al basalts are old (>4 Ga), and the sample data suggests there are at least three and possibly five distinct sources and episodes of volcanism represented at the Apollo 14 site alone. Exposures of these basalts near the Apollo 14 are likely masked by ejecta from the Imbrium impact, which is responsible for the formation of the Apollo 14 breccias and post-dates eruption of the basalts. This suggests that they could be a significant component of ancient basalts that are now buried beneath impact deposits (cryptomare). The existence of younger aluminous basalts at the Apollo 12 and Luna 16 sites suggest that aluminous basaltic volcanism spanned over a billion years. The high-Al nature of these basalts suggests they are derived from a relatively Al-rich source. This Al probably comes from the presence of plagioclase in the source, which implies that plagioclase flotation was inefficient in the Lunar Magma Ocean (LMO) and that some remains within the uppermost lunar mantle. Identifying high-Al basalt exposures is necessary for locating potential future sampling sites as they may represent outcrops of pre-4 Ga volcanism and be a window to early processes. ... more>>
Prospero 8/12/2008 | 0 (0) | 78 | 0 | 0 | English
Gillis, Lucey, Campbell and Hawke, Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu & Center for Earth and Planetary Studies, Smithsonian Institution, Washington. - Introduction: Examination of the correlation between UV/VIS ratio and TiO2 has revealed that UVVIS color is not only a function of the TiO2 content of mare soils but also includes spectral properties of a multitude of components that impart color to lunar soils. Hence, UVVIS color is not a reliable predictor of Ti without the use of additional information to provide other constraints. Recently calibrated Clementine near infrared data (NIR) and newly acquired 70-cm backscatter radar data may provide these additional and important constrains as both data sets provide independent information concerning ilmenite content in the lunar regolith. ... more>>
Prospero 8/12/2008 | 0 (0) | 39 | 0 | 0 | English
Beck, Morgan, Liang and P. Hess; Brown University, Providence. - Experimentally determined multisaturation depths for the lunar picritic glasses suggest that the source region for the glasses is very deep, on the order of 500 km for the Apollo 14 picritic green glasses and the Apollo 15 picritic red glasses. These depths are believed to be a minimum estimate because the glasses have all experienced near surface fractionation of olivine. If multisaturation truly represents a minimum or even average depth of melting, it is very important to understand the extent to which the glasses have reacted with the lunar mantle during their long ascent to the surface. ... more>>
Prospero 8/12/2008 | 0 (0) | 35 | 0 | 0 | English
Cahill, Lucey, Steutel and Gillis, Hawaii Institute of Geophysics and Planetology, Univ. of Hawaii at Manoa, Honolulu. - Mg-number (Mg#=atomic Mg/(Mg+Fe)) serves as an important petrologic discriminator when analyzing and understanding lunar rocks and crustal evolutionary models. Here we present a new data set of Mg# for the lunar surface that can be used to evaluate crustal materials and modeling in greater spatial and geochemical detail. ... more>>
Prospero 8/12/2008 | 0 (0) | 34 | 0 | 0 | English
Paul H. Warren, Eric Tonui and Edward D. Young, Institute of Geophysics, UCLA, Los Angeles. - Volatile depletion was a ubiquitous concomitant of planet formation, especially in the inner solar system. Isotopic variations of Mg, a major element with three stable isotopes, can potentially provide insight into this important aspect of planetary origin. ... more>>
Prospero 8/12/2008 | 0 (0) | 30 | 0 | 0 | English
Archinal, Rosiek and Redding, U. S. Geological Survey, Flagstaff. There are currently two generally accepted lunar control networks. These are the Unified Lunar Control Network (ULCN) and the Clementine Lunar Control Network (CLCN), both derived by M. Davies and T. Colvin at RAND. We address here our efforts to merge and improve these networks into a new ULCN. ... more>>
Prospero 8/12/2008 | 0 (0) | 54 | 0 | 0 | English
Kobayashi, Berezhnoy, d’Uston, Fujii, Hasebe, Hiroishi, Kaneko, Miyachi, Mori, Maurice, Nakazawa, Narasaki, Okudaira, Shibamura, Takashima, Yamashita; Advanced Research Institute of Sci.& Eng., Waseda Univ. Tokyo; Institute of Space and Astronautical Science, Japan Aerospace Exploration Agency, Kanagawa, Niihama Works, Sumitomo Heavy Industry Ltd., Niihama, Ehime, Moriya Works, Meisei Electric Co., Ltd., Clear Pulse Co., Tokyo, Japan & Centre d’Etude Spatiale des Rayonnements, CNRS/UPS, Colonel Roche, France. - Elemental composition on the surface of a planet is very important information for solving the origin and the evolution of the planet and also very necessary for understanding the origin and the evolution of solar system. Planetary gamma-ray spectroscopy is extremely powerful approach for the elemental composition measurement. Gamma-ray spectrometer (GRS) will be on board SELENE (Kayuga), advanced lunar polar orbiter, and employ a large-volume Ge detector of 252cc as the main detector. SELENE (Kayuga) GRS is, therefore, approximately twice more sensitivity than Lunar Prospector GRS, four times more sensitive than APOLLO GRS. The high sensitivity of SELENE GRS will enable us to map element abundances of O, Mg, Fe, Al, Si, Ti, K, Ca, Th, and U, with lower detection limit than the past missions. The Japanese lunar polar orbiter SELENE is scheduled for launch in 2007 and the GRS will observe the whole area of the moon including the polar region. ... more>>
|