Bangalore, Nov 10: Scientists at ISRO Telemetry, tracking and command network (ISTRAC) in the city carried out successfully the first orbit reduction manoeuvre of India's first unmanned moon mission Chandrayaan-1 on Sunday, Nov 9.
According to a press release from ISRO the manoeuvre which began at 8:03 pm firing the 440 Newton liquid engine of the spacecraft for about 57 seconds. With this, the nearest point of Chandrayaan-1's orbit- periselene from the moon's surface was reduced from 504 km to 200 km, while the farthest point-aposelene- remained unchanged at 75,502 km, the release said. Further orbit reduction manoeuvers are scheduled in the coming days to take Chandrayaan-1, which was launched from Sriharikota on October 22, to its final operational orbit of 100 km height from the lunar surface by November 15. After this the Moon impact probe would be released to hit the moon's surface and ten other scientific instruments start their operations.
The health as well as orbit of the spacecraft was being closely monitored from ISTRAC with crucial support from Indian Deep Space Network antennas at Bylalu, 45 km from the city.
The spacecraft performance was normal. The lunar orbit insertion manoeuvre was successfully performed on Saturday and the spacecraft entered into an orbit around the moon with a periselene of 504 km and an aposelene of 7502 km.