نتایج جستجو برای: lunar months

تعداد نتایج: 341049  

2014
Jasmeet Kaur A. Schoonen Douglas Rickman

Introduction: The current interest in human exploration of the Moon and past experiences of Apollo astronauts has rekindled research into the harmful effects of Lunar dust on human health. While the mineralogical composition of lunar regolith has been well documented, other factors, such as partial melting due to space weathering, UV irradiation, and dryness may also contribute to the toxicity ...

2014
S. Davis J. Marshall D. Richard D. Adler B. Adler

A number of space missions are planned to explore the lunar exosphere which may contain a small population of dust particles. The objective of this paper is to present preliminary results from scattering experiments on a suspension of lunar simulants to support one such mission. The intensity of the light scattered from a lunar simulant is measured with a commercial version of the spectrometer ...

Journal: :Science 2000
B A Cohen T D Swindle D A Kring

Lunar meteorites represent a more random sampling of lunar material than the Apollo or Luna collections and, as such, lunar meteorite impact melt ages are the most important data in nearly 30 years with which to reexamine the lunar cataclysm hypothesis. Within the lunar meteorite breccias MAC 88105, QUE 93069, DaG 262, and DaG 400, seven to nine different impact events are represented with 40Ar...

2007
Kenji NAGAOKA Takashi KUBOTA Ichiro NAKATANI Satoshi TANAKA

Lunar and planetary subsurface exploration is of considerable significance. The authors have studied the strategies for subsurface excavation and propulsion for the development of a lunar subsurface explorer. The authors have proposed an autonomous robotic explorer which can burrow into the soils. Based on the strategies the authors have already considered, this paper especially focuses on the ...

Journal: :Science 1996
S Nozette C L Lichtenberg P Spudis R Bonner W Ort E Malaret M Robinson E M Shoemaker

During the Clementine 1 mission, a bistatic radar experiment measured the magnitude and polarization of the radar echo versus bistatic angle, beta, for selected lunar areas. Observations of the lunar south pole yield a same-sense polarization enhancement around beta = 0. Analysis shows that the observed enhancement is localized to the permanently shadowed regions of the lunar south pole. Radar ...

2007
M. S. Robinson B. W. Hapke J. B. Garvin D. Skillman J. F. Bell M. P. Ulmer C. M. Pieters

[1] Samples of the lunar regolith returned by Apollo astronauts show large variations (0 to >10 wt%) in TiO2 abundance indicating complex compositional zonation within the lunar mantle. A long held goal of the lunar science community is the accurate determination of TiO2 abundances on the lunar surface through remote sensing methods. To date only limited progress has been made in this area usin...

2015
Jessica J. baRnes chaRles K. sheaReR Mahesh anand

Many studies exist on magmatic volatiles (H, C, N, F, S, Cl) in and on the Moon, within the last several years, that have cast into question the post-Apollo view of lunar formation, the distribution and sources of volatiles in the Earth-Moon system, and the thermal and magmatic evolution of the Moon. However, these recent observations are not the first data on lunar volatiles. When Apollo sampl...

2007
Dale Arney Joseph Hickman Philip Tanner John Wagner Marc Wilson Alan Wilhite

A lunar lander is designed to provide safe, reliable, and continuous access to the lunar surface by the year 2020. The NASA Exploration System Architecture is used to initially define the concept of operations, architecture elements, and overall system requirements. The design evaluates revolutionary concepts and technologies to improve the performance and safety of the lunar lander while minim...

Journal: :Science 2005
Thorsten Kleine Herbert Palme Klaus Mezger Alex N Halliday

The use of hafnium-tungsten chronometry to date the Moon is hampered by cosmogenic tungsten-182 production mainly by neutron capture of tantalum-181 at the lunar surface. We report tungsten isotope data for lunar metals, which contain no 181Ta-derived cosmogenic 182W. The data reveal differences in indigenous 182W/184W of lunar mantle reservoirs, indicating crystallization of the lunar magma oc...

2007
Michael J. Oard

Over one thousand lunar transient events have been reported since the 1600s when telescopes were fi rst developed. Astronomer William Herschel during 1783–1787 reported several apparent lunar volcanic emissions: ‘I perceived in the dark part of the Moon a luminous spot. It had the appearance of a red star.’ Four years later Herschel wrote, ‘I perceive three volcanoes ... The third shows signs o...

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