Last month, ISRO faced a strange situation when Chandrayaan-2 and NASA’s Lunar Reconnaissance Orbiter came very close to colliding. The Indian Space Research Organization (ISRO) has revealed that the Chandrayaan-2 orbiter was modified to prevent it from colliding with NASA’s Lunar Reconnaissance Orbiter (LRO) in October. It was transferred from its polar orbit last month to avoid a collision with NASA’s LRO near the North Pole.
Last month the distance between Chandrayaan-2 orbiter and LRO was very less. The radial separation between the spacecraft would be less than 100 meters and the closest distance would be only 3 km at the above time, it observed in analysis by both ISRO and JPL/NASA a week before these two came close. This information was given by ISRO.
It has been said by ISRO that both the agencies agreed that collision avoidance manoeuvre (CAM) is needed to reduce such risk. Both the agencies had agreed that ISRO’s orbiter would pass through it. Chandrayaan-2 and LRO orbit the Moon in a near-polar orbit and hence both the spacecraft come close to each other at the lunar poles.
After orbit determination with tracking it was confirmed in the data that there would be no close association with LRO in the near future. It is common for satellites in Earth orbit to undergo CAM to reduce the risk of collisions caused by space objects, including space debris and operational spacecraft.
ISRO monitors such cases and changes are made according to the risk. However, this is the first time the space mission of ISRO faced such difficulties and it was a different experience.