The Mars Odyssey Gamma-Ray Spectrometer Instrument Suite
W.V.Boyton1*, W.C.Feldman2, I.G.Mitrofanov3, L.G.Evans4, R.C.Reedy5, S.W.Squyres6, R.Starr7, J.I.Trombka8, C.d'Uston9, J.R.Arnold10, P.A.J.Englert11, A.E.Metzger12, H.Wänke13, J.Brückner13, D.M.Drake14, C.Shinohara1, C.Fellows1, D.K.Hamara1, K.Harshman1, K.Kerry1, C.Turner1, M.Ward1, H.Barthe9, K. R.Fuller2, S.A.Storms2, G.W.Thornton2, J.L.Longmire2, M.L.Litvak3 and A.K.Ton'chev3
1 University of Arizona, Lunar and Planetary Laboratory, Tucson, AZ 85721, U.S.A.
2 Los Alamos National Laboratory, Los Alamos, NM 87545, USA.
3 Space Research Institute, Moscow
4 Science Programs, Computer Sciences Corporation, Lanham, MD 20706, USA.
5 Institute of Meteoritics, University of New Mexico, Albuquerque, NM 87131, USA.
6Cornell University, Center for Radiophysics & Space Research, Ithaca, NY 14853, U.S.A.
7 Department of Physics, The Catholic University of America, Washington, DC 20064, USA.
8 NASA/Goddard Space Flight Center, Greenbelt, MD 20771, USA.
9 Centre d'Etude Spatiale des Rayonnements, Toulouse, France.
10 University of California San Diego, Department of Chemistry, La Jolla, CA 92093, U.S.A.
11University of Hawaii, Manoa, HI, U.S.A.
12 Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109, U.S.A.
13 Max-Planck-Institut für Chemie, 6500 Mainz, Federal Republic of Germany
14 TechSource, Sante Fe, NM 87505, U.S.A.
(*Author for correspondence, E-mail: This email address is being protected from spambots. You need JavaScript enabled to view it.)
Abstract - The Mars Odyssey Gamma-Ray Spectrometer is a suite of three different instruments, a gamma subsystem (GS), a neutron spectrometer, and a high-energy neutron detector, working together to collect data that will permit the mapping of elemental concentrations on the surface of Mars. The instruments are complimentary in that the neutron instruments have greater sensitivity to low amounts of hydrogen, but their signals saturate as the hydrogen content gets high. The hydrogen signal in the GS, on the other hand, does not saturate at high hydrogen contents and is sensitive to small differences in hydrogen content even when hydrogen is very abundant. The hydrogen signal in the neutron instruments and the GS have a different dependence on depth, and thus by combining both data sets we can infer not only the amount of hydrogen, but constrain its distribution with depth. In addition to hydrogen, the GS determines the abundances of several other elements. The instruments, the basis of the technique, and the data processing requirements are described as are some expected applications of the data to scientific problems.
DOI: 10.1023/B:SPAC.0000021007.76126.15 - http://www.springerlink.com/content/u084216222271712/