NSSDCA ID: 2003-022A-02
Mission Name: Mars ExpressThe Infrared Mineralogical Mapping Spectrometer, or Observatoire pour la Mineralogie, l'Eau, les Glaces et l'Activit (OMEGA) is a visible and near-infrared mapping spectrometer designed to provide global data on the mineralogical and molecular composition of the martian surface at medium resolution. The instrument will spectrally analyze re-diffused solar light and surface thermal emission. The scientific objectives are to characterize the composition of surface material and monitor atmospheric dust and aerosols.
OMEGA will provide spectra of the atmosphere from 0.5 to 5.2 microns. It has two independent channels, a visible band channel (0.5 to 1.1 microns) and a near-infrared band channel (1.0 to 5.2 microns). Each channel is equipped with its own telescope, spectrometer, and detection system. The visible channel works in pushbroom mode, with the visible band signal directed through a holographic grating to a 384 x 288 pixel (spatial x spectral) Thompson CCD array. Total field of view is 8.8 degrees, but the pixels are binned 3x3 or 3x2, giving a spatial sampling (IFOV) of 4.1 arcmin, corresponding to roughly 350 m to 10 km depending on spacecraft altitude and a spectral sampling of 7 nm or 4 nm. The near-infrared channel works in whiskbroom mode. The incoming beam is divided into two subchannels, each using a grating spectrometer. The beam is directed to an InSb array with 4.1 arcmin IFOV and a spectral resolution of 13 to 20 nm. A crosstrack scanning mechanism is used to build swaths of 16, 32, 64, or 128 IFOV width.
The instrument will be used to attempt detection of carbonate-rich regions and other minor mineral phases on the surface and to study atmospheric characteristics such as abundance and variability of minor components, aerosols, and limb stratification. The OMEGA instument is derived from the Russian Mars-96 mission. The instrument has been developed at IAS and LESIA (Paris Observatory), with support from CNES, and at IFSI 5Italy) and IKI (Russia).
Mass: 29 kg
Questions and comments about this experiment can be directed to: Dr. David R. Williams
Name | Role | Original Affiliation | |
---|---|---|---|
Dr. Jean-Pierre Bibring | Principal Investigator | jean-pierre.bibring@ias.u-psud.fr |