Posted on behalf of Sanjay Kumar.
[Update 12 November: The Indian Space Research Organization has announced that it successfully completed the orbit-raising maneuver of the Mangalyaan probe in the early morning today. The apogee height was raised to 118,642 kilometres, well above the 100,000 km required in the mission’s original plans.]
India’s first Mars mission, a probe named Mangalyaan that lifted off on 5 November, hit its first rough pocket early today, before even leaving Earth orbit.
Five days after launch, the satellite failed to raise its orbit to reach its planned farthest point (apogee) of 100,000 kilometres from Earth. Rather, it only raised it to less than 79,000 km. As a consequence, it is behind schedule with increasing its velocity so that it can later catapult to Mars, says the Indian Space Research Organization (ISRO).
The ISRO had planned a circuitous route so that the probe could be launched using a less powerful but well-tested rocket, the Polar Satellite Launch Vehicle, instead of a more powerful one. This meant first sending the satellite to revolve around the Earth in an elliptical orbit, gradually increasing its orbit length as well as its velocity by firing its liquid-fuel engine. The goal of that flight plan was to use Earth’s gravitational field as a slingshot to get the probe on its 780-million-km journey to the red planet.
ISRO has been under attack from its critics, including its former chief, G. Madhavan Nair, for being in a hurry to launch the satellite rather than wait until it could perfect the more powerful Geo Synchronous Launch Vehicle, which has seen repeated failures since 2001. Nair has dubbed the Mars mission a publicity stunt.
The probe performed three orbit-raising maneuvers successfully on 7, 8 and 9 November, ISRO said in a jargon-laden press release. But during the fourth orbit-raising operation early today, the engine underperformed. “When both primary and redundant coils were energized together, as one of the planned modes, the flow to the liquid engine stopped,” said the ISRO statement.
Mission control, however, has not lost hope. ISRO anticipates that with further orbit-raising maneuvers, the spacecraft will be put on its trajectory to Mars on 1 December.
ISRO’s spokesman Deviprasad Karnik says ISRO has two other options available for getting the engine to perform properly, and will conduct the maneuver again tomorrow.