Russia's Luna-25 automatic landing module crashed because its engine did not turn of normally and worked 127 seconds instead of 84 during a transition to the pre-landing orbit, Yuri Borisov, the head of Russian state space corporation Roscosmos, said on Monday.
"Unfortunately, the engine shutdown did not occur normally, in accordance with the cyclogram, but according to a time cutoff, and instead of the planned 84 seconds, it worked for 127 seconds. This was the main cause of the accident of the device," Borisov told the Rossiya 24 broadcaster.
According to the Roscosmos head, the transition to the pre-landing orbit took place in a radio communication zone, and experts knew everything about the spacecraft before its crash.
"Preliminary ballistic calculations showed that due to the abnormal operation of the corrective propulsion system, the device switched to an open lunar orbit and, in fact, crashed into the surface of the Moon," Borisov said.