Paris, January 30 (ANI): Mars Express completed its 7777th orbit around the Red Planet on January 26, which is 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 December 25, 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. his week, the orbiter completed 7777 circuits of the planet and continues to operate flawlessly.
Currently, each orbit takes 6 hours and 54 minutes.
The spacecraft is following a polar orbit, and at closest approach passes just 350 km above the surface of Mars and, at farthest approach, 10,300 km.
This highly elliptical orbit will enable Mars Express, on March 3, 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.
This close flyby will be bracketed by similarly close passages, which will be used for other scientific investigations including radar sounding and imaging.
Knowing the gravity field will help scientists to understand the distribution of mass inside the moon, which is another step in the quest to discover the origin of Phobos.
While Mars is the mission's primary target, this flyby is an excellent opportunity for additional scientific investigation of the Mars system, and will boost overall science return. (ANI)