The NEAR X-Ray/Gamma-Ray Spectrometer
نویسندگان
چکیده
he X-Ray/Gamma-Ray Spectrometer on the Near Earth Asteroid Rendezvous (NEAR) spacecraft will remotely sense X-ray and gamma-ray emissions from the surface of near-Earth asteroid 433 Eros and look for characteristic “signatures” in those emissions to determine its elemental composition. During the planned 10 months of orbits about Eros beginning in early 1999, data returned from the instrument will be used to develop global maps of the asteroid, including the content and variations of its surface composition, thereby providing important clues about its nature and origin. (
منابع مشابه
Hydrogen and major element concentrations on 433 Eros: Evidence for an L‐ or LL‐chondrite‐like surface composition
A reanalysis of NEAR X-ray/gamma-ray spectrometer (XGRS) data provides robust evidence that the elemental composition of the near-Earth asteroid 433 Eros is consistent with the L and LL ordinary chondrites. These results facilitated the use of the gamma-ray measurements to produce the first in situ measurement of hydrogen concentrations on an asteroid. The measured value, 1100-700+1600 ppm, is ...
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