India's Mars Orbiter Mission – aka MOM – has celebrated its 1,000th Earth day in orbit around the red planet.
The probe arrived on November 5, 2013 and last week ticked over into four figures. The mission cost a pittance or, as the Indian Space Research Organisation (ISRO) puts it, MOM “is credited with many laurels like cost-effectiveness, short period of realisation, economical mass-budget, miniaturisation of five heterogeneous science payloads etc.”
But the agency has detailed that recent efforts to keep MOM circling Mars have come at a cost. AS ISRO explains, MOM is periodically eclipsed and cannot see the sun during those times. As the craft's batteries are designed to survive only a 100-minute eclipse, a pending eight-hour eclipse presented a problem.
MOM solved it by burning its engines for 431 seconds to reach a new orbit in which it won't be eclipsed again until September 2017. But in so doing it burned 20 kilograms of propellant, leaving just 13kg in the tank.
That's not an immediate problem, because the craft only used about 7kg between its orbital insertion in late 2013 and the January 2017 eclipse-avoidance manoeuvres. But just 13kg left, the craft has scant resources if it needs to avoid another long eclipse, or conduct a long burn for some other reason.
Yet India wouldn't be unduly upset if MOM were to break tomorrow, as it was expected to last six months and has instead clocked up more than 30 months in orbit. ISRO reports it is “in good health and continues to work as expected.”
The agency also reports that 1,381 registered users are working on data released from the probe and proudly links to the Martian Atlas (PDF) it created using images shot by the vehicle's Mars Colour Camera. ®