Mars Global Surveyor spacecraft

These are applicable to the 10 cm spectral resolution measurements obtained by the Thermal Emission Spectrometer carried on the Mars Global Surveyor spacecraft (Christensen et al., 1998), and points on both sides of the 15 pun CO2 band are included. Rapid calculation of atmospheric transmittances is required for temperature retrieval from a large volume of spacecraftmeasurements, and the A -distribution method is used (Goody Yung, 1989). 

Spectrometers on several spacecraft have provided information on the mineralogy of the martian surface, but only one set of spectral data is sufficiently quantitative to be recast into geochemistry. The thermal emission spectrometer (TES) on Mars Global Surveyor and the thermal emission spectrometer imaging system (THEMIS) on Mars Odyssey have provided global mineral mapping, and linear deconvolution allows the... 

The accepted mean density of Mars, based on its measured volume and determination of its mass from spacecraft orbits, is 3.9335 0.0004 g cm (Lodders and Fegley, 1998). The density of the elastic lithosphere (approximately equivalent to the crust), estimated from models of the relationship between gravity and topography from Mars Global Surveyor data, is 2.95-2.99 g cm (McKenzie et al., 2002), which is similar to the density of basalt. The planet s dimensionless moment of inertia (0.3662 0.0017), calculated from Mars Pathfinder measurement of the rate at which its spin pole precesses (Folkner et al., 1997), constrains the core radius to —1,300-1,500 km, depending on core composition. 

Solar cells generate electricity in the sunshine but not in the dark. Thus space stations and spacecraft nui on power from batteries during dark periods. As of Jtme 2003, solar power has been practical for spacecraft operating no farther from the Stm than the orbit ofMars. For example, Magellan, Mars Global Surveyor, Mars Observer, and the Earth-orbiting Hubble Space Telescope operate on solar power. 

The Mars Global Surveyor launched from ( ape Canaveral in Ntivember 19%. It reached Mars orbit ill 1997. One of live instruments on board was an IR emission spectrometer, called a thermal emission spec-Ironieier. The spacecraft eompicled its mapping mission in 2iXJl. providing measurements of the Martian surface and atmosphere. The Mar> rt)ver Spirit has u... 

BARNEY CONRATH was affiliated to the Goddard Space Flight Center from 1960 until 1995 and is currently a visiting faculty member in the Cornell University Center for Radiophysics and Space Research. His research interests include the study of the thermal structure, composition, and d5mamics of planetary atmospheres. He has participated in spacecraft missions to the Earth, Mars, and the outer planets, and is currently a member of the infrared spectrometer teams on the Mars Global Surveyor and Cassini missions. 

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