Isro manoeuvre avoids close approach with Nasa’s LRO
NEW DELHI: The lunar orbiter of the Chandrayaan-2 mission, which was successfully deployed in 2019, was moved from its 100km circular polar orbit last month to avoid a close approach with Nasa’s Lunar Reconnaissance Orbiter (LRO) near the moon’s north pole, Indian Space Research Organisation (Isro) said on Monday.
This was the first close approach manoeuvre that Isro has undertaken for a space exploration mission. The Indian space agency closely monitors the space for debris and other satellites to avoid a collision. All such manoeuvres have so far been restricted to satellites orbiting the earth, Isro said in a statement.
Very close conjunction between the Indian and the US orbiters, both of which are in a polar orbit that crosses over both poles of the moon, was expected to occur on October 20 at 11.15am.
At that time, the distance between the orbits of the two spacecraft would have been less than 100m. The satellites would have been at a distance of just about 3km at the time of closest approach, Isro said. This was a very small distance for fast-moving satellites that travel several kilometres in a second.
Isro and Nasa, the American space agency, realised that a manoeuvre was needed to mitigate a collision. It was mutually agreed that the Chandrayaan-2 orbiter would be moved to ensure that there is a large separation during their next close conjunction, the Indian statement said.
The manoeuvre was carried out on October 18 at 8.22pm. “After orbit determination of CH2O (Chandrayaan-2 Orbiter) with post-manoeuvre tracking data, it was reconfirmed that there would be no further close conjunctions with LRO in the near future with the achieved
CHANDRAYAAN-2 ORBITER, WHICH HAS A SLATED MISSION LIFE OF SEVEN YEARS, WILL BE USED FOR THE UPCOMING CHANDRAYAAN-3 MISSION
orbit,” Isro added in its statement. The Chandrayaan-2 orbiter, which has a slated mission life of seven years, will be used for the upcoming Chandrayaan-3 mission that will carry only the lander and the rover.
The lander-rover aboard the Chandrayaan 2 mission crashlanded on the lunar surface just 2.1km from its destination on September 7, 2019. A successful soft-landing would have made India only the fourth country after the US, Russia, and China to have successfully landed a celestial object on the moon.
Israel’s Beresheet, which attempted a soft landing, also crashed into the lunar surface in April, 2019.