By IANS,
Bangalore : India’s first unmanned lunar spacecraft Chandrayaan-1 is doing fine and has completed four orbits around the earth, a top space official said Thursday, a day after it was launched from Sriharikota in Andhra Pradesh.
“The health of the spacecraft is normal and (it is) doing fine. Spinning in elliptical orbit once in every six hours and 30 minutes, it has completed four orbits and is in the fifth orbit,” the official told IANS.
The 1,380 kg Chandrayaan also responded well to commands given to manoeuvre its movement in the orbit from the Indian Space Research Organisation (ISRO) ground station – the telemetry, tracking and command network (Istrac) in India’s tech hub.
“The first orbital manoeuvre planned for Thursday was carried successfully at the pre-determined time (9 a.m.) and the spacecraft’s position in the orbit is adjusted by firing the LAM (liquid apogee motor) of 440 Newton,” the official said.
The spacecraft was put into transfer orbit with a perigee (nearest point to earth) of 255 km and an apogee (farthest point from earth) of 22,860 km, inclined at an angle of 17.9 degrees to the equator 18.9 minutes after it was blasted off at 6.22 a.m. on board the 316-tonne polar satellite launch vehicle (PSLV-C11) from the Satish Dhawan Space Centre in Sriharikota, 80 km north of Chennai.
“The spacecraft is in constant touch with the command network and has been receiving signals sent time-to-time. A similar exercise (manoeuvre) will be carried out Friday as programmed,” the official added.
Chandrayaan project director M. Annadurai told IANS that a series of manoeuvres would be carried out over the next 10-12 days in the geo-transfer orbit to enable the spacecraft enter the lunar orbit Nov 3.
“The spacecraft will enter the lunar orbit Nov 3 when the moon will be about 500 km away (perigee). We will do an electrical firing (LAM) to make the satellite go around the moon in its orbit,” Annadurai noted.
A series of complex manoeuvres in the final phase will put Chandrayaan in the final orbit Nov 8, which will be about 100 km from the moon’s surface.
“All going well, we plan to send down the moon impact probe Nov 15 for conducting experiments before and after crashing into the lunar planet,” Annadurai added.