ESA’s latest Mars orbiter has moved itself into a new path on its way to achieving the final orbit for probing the Red Planet.
The ExoMars Trace Gas Orbiter arrived last October on a multiyear mission to understand the tiny amounts of methane and other gases in the atmosphere that could be evidence for biological or geological activity.
In January, it conducted a series of crucial manoeuvres, firing its main engine to adjust its orbit around Mars. The three firings shifted its angle of travel with respect to the equator to almost 74° from the 7° of its October arrival. This essentially raised the orbit from equatorial to being much more north–south.
The arrival orbit was set so that it could deliver the Schiaparelli lander to Meridiani Planum, near the equator, with good communications.
Once science observations begin next year, the new 74º orbit will provide optimum coverage of the surface for the instruments, while still offering good visibility for relaying data from current and future landers. (…)
The inclination change was also a necessary step for the next challenge: a [13-] months-long ‘aerobraking’ campaign designed to bring the spacecraft to its near-circular final science orbit, at an altitude of around 400 km. [More at link]