The orbital probe of the lunar Indian mission "Chandrayan-2" performed an evasion maneuver to prevent close encounters with the NASA Lunar Reconnaissance Orbiter (LRO) probe in mid-October this year.
Calculations carried out after the maneuver showed that in the near future there will be no such close encounters of vehicles.
To date, five spacecraft operate in circumlunar orbits.
Two probes of the ARTEMIS mission investigate the interaction of the Moon with the solar wind.
The Lunar Reconnaissance Orbiter, which is engaged in surface mapping.
The Chinese satellite Queqiao rebroadcasts the signals of the Yuytu-2 lunar rover from the far side of the Moon.
And the Indian Chandrayan-2 is engaged in comprehensive research of the Moon.
Chandrayan-2 and the Lunar Reconnaissance Orbiter are in polar circumlunar orbits, so both vehicles are able to appreciably approach each other over the lunar polar regions.
A very close encounter of the probes was expected on the morning of October 20, 2021, over the moon's north pole.
Calculations were carried out a week before the rendezvous by the Indian Space Research Organization (ISRO) and NASA specialists.
The data showed that the radial separation of the vehicles will be less than one hundred meters, and the distance of the minimum approach will be three kilometers.
Both space agencies concluded that a collision avoidance maneuver was needed, which, by mutual agreement, was to be performed by Chandrayan II.
The maneuver itself was carried out in the afternoon of October 18, 2021, after which the experts determined that there would be no close convergence of the two vehicles in the near future.
For ISRO, this was the first time an interplanetary vehicle had evaded another vehicle.