On 2019-09-06 the Indian Space Research Organisation’s (ISRO) Chandrayaan-2 lunar exploration spacecraft, which had arrived in lunar orbit on 2019-08-20 and separated its lunar landing component, Vikram on 2019-09-02, began its lunar landing attempt, with Vikram braking from its lunar orbit with a goal of soft landing in the lunar south polar region at 70.9° south latitude and 22.8° west longitude, 600 km from the lunar south pole. This was not to be, with telemetry from the lander showing it making a final descent much too fast for soft landing, followed by loss of signal. There followed a Soviet-style silence, with anonymous reports from ISRO personnel that the lander was on the surface but in a tilted orientation and unable to communicate with Earth.
Independent analysis of radio transmissions by observers in other countries indicated the lander had crashed on the Moon and eventually NASA’s Lunar Reconnaissance Orbiter imaged the impact site, removing any doubt about the spacecraft’s fate.
Now, almost four years later, ISRO dirrector S. Somanath presented a detailed description of Vikram’s crash on the Moon, caused by a combination of a rocket engine not performing as expected and flight software unable to compensate for the resulting deviation from the planned trajectory. This was part of a conference held on 2023-08-05. I have cued the following video to start at the talk “Chandrayaan-2 Mission & Outcome” at the 37:27 point; skip back to the beginning if you want to see the whole thing.
The audio and image quality in this live stream is execrable: “If they can put a pile of rubble on the Moon, why can’t they make an audio recording that’s intelligible?” It’s one of those mysteries of 21st century technology.
On 2023-07-14, Chandrayaan-3, ISRO’s next attempt to land on the Moon, was launched and is as this writing (2023-08-11) in lunar orbit, with a plan for its lander and rover to attempt landing on 2023-08-23. This mission does not include an orbiter to observe the Moon after releasing the lander: the spacecraft is simply a ferry to carry the lander to its release point in lunar orbit.
