NASA finds ISRO Lunar Orbiter Chandrayaan-1

NASA finds Indian’s lost lunar orbiter Chandrayaan 1

The U.S. space agency NASA has discovered the location of India’s first lunar orbiter, Chandrayaan 1, which lost contact with mission managers back in 2009. Within a year of its launch, Chandrayaan-I lost contact with its mission base station.

Chandrayaan 1 spacecraft was launched by the Indian Space Research Organisation (ISRO) on October 22, 2008 to orbit the Earth’s only natural satellite.

The spacecraft found signs of presence of water on the surface of the Moon on 14th of November last year. Unfortunately, ISRO lost contact with the probe on August 29, 2009. Experts estimated that the most probable cause of the loss of contact was a tragic crash.

NASA recently announced that its latest radar technology discovered the Chandrayaan 1 spacecraft. The same technology, pioneered by the agency’s Jet Propulsion Laboratory (JPL), also located the agency’s Lunar Reconnaissance Orbiter.

Announcing the discovery of the lost probe, NASA added, “This technique could assist planners of future moon missions.”

Krishnaswamy Kasturirangan, the founder of India’s lunar mission, declared the discovery of the lost spacecraft a “great” accomplishment. Meanwhile, the ISRO is making preparations for its Chandrayaan 2 mission, which is scheduled to be launched in 2018.

Marina Brozovic, a radar scientist with NASA informed, "We have been able to detect NASA's Lunar Reconnaissance Orbiter and the Indian Space Research Organisation's Chandrayaan-1 spacecraft in lunar orbit with ground-based radar. Finding India's Chandrayaan-1 required a bit more detective work because the last contact with the spacecraft was in August of 2009.”

A report published by PC Mag informed, “Chandrayaan-1 was located using NASA's Goldstone Deep Space Communications Complex in California and a beam of microwaves. The radar echoes bounced back were received by the Green Bank Telescope in West Virginia. The only lead they had to go on was the spacecraft's last known orbit from 2009, which was a polar orbit, so the beam was focused on the moon's north pole hoping the spacecraft would pass by.”

The official NASA JPL release informed....

Finding a derelict spacecraft at lunar distance that has not been tracked for years is tricky because the moon is riddled with mascons (regions with higher-than-average gravitational pull) that can dramatically affect a spacecraft's orbit over time, and even cause it to have crashed into the moon. JPL's orbital calculations indicated that Chandrayaan-1 is still circling some 124 miles (200 kilometers) above the lunar surface, but it was generally considered "lost."

However, with Chandrayaan-1, the radar team utilized the fact that this spacecraft is in polar orbit around the moon, so it would always cross above the lunar poles on each orbit. So, on July 2, 2016, the team pointed Goldstone and Green Bank at a location about 100 miles (160 kilometers) above the moon's north pole and waited to see if the lost spacecraft crossed the radar beam. Chandrayaan-1 was predicted to complete one orbit around the moon every two hours and 8 minutes. Something that had a radar signature of a small spacecraft did cross the beam twice during four hours of observations, and the timings between detections matched the time it would take Chandrayaan-1 to complete one orbit and return to the same position above the moon's pole.

The team used data from the return signal to estimate its velocity and the distance to the target. This information was then used to update the orbital predictions for Chandrayaan-1.

"It turns out that we needed to shift the location of Chandrayaan-1 by about 180 degrees, or half a cycle from the old orbital estimates from 2009," said Ryan Park, the manager of JPL's Solar System Dynamics group, who delivered the new orbit back to the radar team. "But otherwise, Chandrayaan-1's orbit still had the shape and alignment that we expected."