|MARS-96      ||ROBOTIC SPACECRAFT MISSION TO MARS. Brief description|
| SCIENTIFIC OBJECTIVES
OF THE ORBITER EXPERIMENTS
The experiments on board the orbiter should study the atmosphere and surface of Mars with remote sensing methods. The main objective of the TV imaging (HRSC and WAOSS) is to investigate the regions selected over the planet as most hydro/cryolithosphere. They are zones of volcanic activity, layered deposits, strong water and wind erosion. Measurements of the elemental composition with a gamma-spectrometer (PHOTON experiment) and of the mineralogical composition with IR-spectrometers (OMEGA and PFS) make it possible to get data about the nature of rocks. A long wave radar (LWR) measures the depth, thickness and latitudinal distribution of permafrost. Remote temperature measurements will be made with a TERMOSCAN instrument and with both IR-spectrometers (OMEGA and PFS).
Several scientific experiments are to investigate the atmosphere. A planetary Fourier-spectrometer, PFS, will get the data on local CO2 band profiles ( = 15 m) which help obtain the three-dimensional distribution of atmospheric temperature. This, in turn, will make it possible to estimate characteristics of winds in the atmosphere. Another source of data on the atmosphere dynamics is the movement of clouds, which will be imaged with HRSC and WAOSS.
The PFS experiment should also monitor the horizontal distribution of water vapour and carbon monoxide. Very little is known about the vertical distribution of minor atmospheric components (H2O, CO, O2, O3). It will be studied using the method of sun and star occultation in the SPICAM experiment. At the same time SPICAM would also measure the vertical distribution of aerosols (mineral dust, condensates of H2O and, possible, of CO2). Information about aerosols will also be provided by TV images taken near the limb.
Global dust storms regularly occur on Mars. TV cameras (HRSC, WAOSS), OMEGA and PFS spectrometers will be used to study their development and to determine characteristics of dust clouds.
A low-pericenter orbit is favourable for direct studies of the composition (MAK experiment) and temperature of the upper atmosphere, measurements of the magnetic field, investigation of plasma processes near Mars, processes of the solar wind interaction with the ionosphere (plasma instruments).
The scientific program of the mission includes experiments which do not require specific instruments on board the spacecraft: