Mars Express

Mission Objectives

• Search for subsurface water
• Global high-resolution photogeology and mineralogical mapping
• Analysis of atmospheric composition and circulation
• Deployment of geochemistry and exobiology lander, Beagle 2, onto the surface
• Communications relay

Mission Name

Mars Express is so called because it was built more quickly than any other comparable planetary mission. The Beagle 2 lander is named after the ship in which Charles Darwin sailed when formulating his ideas about evolution.

Spacecraft

Instruments

• High Resolution Stereo Camera (HRSC) - High resolution surface imaging 
• Energetic Neutron Atoms Analyser (ASPERA) - How the solar wind erodes the Martian atmosphere
• Planetary Fourier Spectrometer (PFS) - Study of the atmospheric composition and circulation 
• Visible and Infrared Mineralogical Mapping Spectrometer (OMEGA) - Determination of the surface composition and evolution processes
• Sub-Surface Sounding Radar Altimeter (MARSIS) - Search for water in the subsurface
• The Radio Science Experiment (MaRS) - Sounding of the internal structure, atmosphere and environment
• Ultraviolet and Infrared Mars Atmospheric Spectrometer (SPICAM) - Determination of the composition of the atmosphere of Mars
• Lander (Beagle 2) - Geochemistry and exobiology

Orbit

Mars Express was launched from the Fregat upper stage towards Mars with an absolute velocity of 116 800 kmh^-1 and a velocity relative to the Earth of 10 800 kmh^-1. On the 19 December 2003, 5 days before orbit insertion, the Beagle 2 lander was successfully released towards the surface of the planet. On 25 December 2003 the orbiter underwent a successful orbit insertion manoeuvre and after slow orbit adjustments it reached the operational orbit.

Nominal Operational Orbit Parameters

• Orbital Inclination - 86.3°
• Apocentre - 11 560 km
• Pericentre - 258 km
• Period - 7.5 h
• Observational Phase at Pericentre - about 1 hour
• Communications Phase - 6.5-7.0 hours minimum

Operations Centre

The European Space Operations Control Centre (ESOC) in Darmstadt will communicate with the spacecraft via the ESA New Norcia ground station in Perth, Australia. The spacecraft will send housekeeping data on instrument temperatures, voltages and spacecraft orientation, for example, and science data. The ground station will send control commands to the spacecraft. Scientific data will be stored onboard using the 12 Gbit solid state mass memory prior to the downlink to Earth.