Documents in the NTIS Technical Reports collection are the results of federally funded research. They are directly submitted to or collected by NTIS from Federal agencies for permanent accessibility to industry, academia and the public.  Before purchasing from NTIS, you may want to check for free access from (1) the issuing organization's website; (2) the U.S. Government Printing Office's Federal Digital System website; (3) the federal government Internet portal; or (4) a web search conducted using a commercial search engine such as
Accession Number N20130009708
Title Constraints on the Compositions of Phobos and Deimos from Mineral Absorptions.
Publication Date Mar 2013
Media Count 2p
Personal Author A. A. Fraeman A. S. Rivkin R. E. Arvidson R. V. Morris S. L. Murchie
Abstract The compositions of Phobos and Deimos have remained controversial despite multiple Earth- and space-based observations acquired during the last 40 years. Phobos is composed of at least two spectral units that are both dark yet distinct at visible to near infrared wavelenghts; a spectrally red-sloped "red" unit covers most of the moon and a less red-sloped "blue" unit is present in the ejecta of the approximately 9-km diameter impact crater Stickney (1,2). Deimos is similar spectrally to Phobos' "red" unit (2). Here we report results from mapping mineral absorptions on Phobos and Deimos using visible/near infrared observations from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM). We find evidence for an absorption feature at 0.65 m in the Phobos red unit and Deimos that is reproducible in observations from other instruments. The phase responsible is uncertain but may be a Fe-bearing phyllosilicate and/or graphite, consistent with the notion that Phobos and Deimos have compositions similar to CM carbonaceous chondrites (3).
Keywords Absorption spectra
Carbonaceous chondrites
Imaging spectrometers
Meteoritic composition
Mineral deposits
Near infrared radiation
Spectral reflectance

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 54 - Astronomy & Astrophysics
84B - Extraterrestial Exploration
Corporate Author National Aeronautics and Space Administration, Houston, TX. Lyndon B. Johnson Space Center.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1319
Contract Number N/A

Science and Technology Highlights

See a sampling of the latest scientific, technical and engineering information from NTIS in the NTIS Technical Reports Newsletter

Acrobat Reader Mobile    Acrobat Reader