On 26 January, Mars Express completed its 7777th orbit around the Red Planet, an auspicious milestone as the satellite is readied for the closest-ever flyby of Phobos, scheduled for just a few weeks from now.
Mars Express has been in orbit since 25 December 2003, returning a wealth of scientific information and some of the most stunning high-resolution imagery of the Red Planet ever. Its data have allowed scientists to measure the abundance of water ice and vapour in the martian subsurface, surface and the atmosphere, as well as previously unknown methane in the atmosphere. Mars Express’ highly elliptical orbit will enable Mars Express, on 3 March, to conduct the closest flyby and examination of Phobos, Mars’ largest moon. The flyby, at a planned altitude of just 50 km, will collect very precise radio Doppler data to help determine the moon’s gravity field more accurately than ever.