On Saturday, Russia's state space corporation Roscosmos said that an emergency situation occurred on board the Luna-25 module that prevented its transition to the pre-landing orbit with the specified parameters. On Sunday, Roscosmos said that Luna-25 seemingly crashed into the Moon's surface after going into an unplanned orbit. Communication with the spacecraft was lost at around 2:57 p.m. Moscow time (11:57 GMT) on Saturday.
"There were issues, they were not that significant, but the signs were, so to speak, worrying, but everyone hoped that they would be able to deal with this somehow ... I will say it carefully, there are calculated things, and there are not nominal [values] ... If a deviation we have turns out to be somewhat higher than we expected, this is a worrying fact, but, apparently, it was not worrying enough to move on to the radical solution," Eismont said.
The scientist added that, given these issues, it was necessary to wait and push back the transition to the pre-landing orbit, adding that there would be "nothing terrible" about this.
"It is sad that there was time and, apparently, the decision taken on how to proceed was not the best," he said.
On August 11, the Soyuz-2.1b carrier rocket lifted off from Russia's Vostochny Cosmodrome and launched into orbit Luna-25, the first Russian lunar mission in almost 50 years and the first one in Russia's independent space history.