Sunday, November 9, 2008

Chandrayaan orbital height reduced

CHENNAI: After successfully accomplishing the most crucial and tricky manoeuvre of safely inserting Chandrayaan-1 into the lunar orbit on Saturday, the Indian Space Research Organisation on Sunday executed the first manoeuvre of reducing the orbital height of the spacecraft around the moon. While on Saturday, Chandrayaan-1 reached the lunar orbit with an aposelene (farthest point from the moon) of 7,502 km and a periselene (nearest point from the moon) of 504 km, the periselene was reduced to 200 km on Sunday. The aposelene continues at 7,500 km. The periselene was reduced by giving commands to the engine on board Chandrayaan-1 to fire for about a minute from 8.03 p.m.

Three more manoeuvres of reducing both the aposelene and periselene will be done in the coming days. This includes the manoeuvre of putting Chandrayaan-1 in the final circular orbit of 100 km above the moon on November 15. After this is done, ISRO will command the spacecraft to eject its Moon Impact Probe on the same day.
The Moon Impact Probe, with the Indian flag painted on its sides, will crash-land on the moon.
Then the remaining 10 scientific instruments will be switched on, one after another.
The Terrain Mapping Camera, an Indian scientific instrument, has already been switched on. It has taken clear pictures of the earth and the moon