By Jackie Wattles and Mariya Knight, CNN
The Luna 25 spacecraft reported an "emergency situation on board," Russia's space agency, Roscosmos, said on Saturday.
An incident occurred as the spacecraft was trying to enter a pre-landing orbit, according to Roscosmos.
"During the operation, an emergency situation occurred on board the automatic station, which did not allow the maneuver to be performed with the specified parameters," Roscosmos said in a Telegram post.
"The management team is currently analyzing the situation," the space agency added.
It's not yet clear if the issue will prevent the lunar lander, which was slated to land near the moon's south pole as soon as Monday, from attempting a touchdown.
Russia's Luna 25 lander mission marked the country's first attempt at landing a spacecraft on the moon since the Soviet era. The last lunar lander, Luna 24, landed on the lunar surface on August 18, 1976.
The spacecraft launched from the Vostochny Cosmodrome in Russia's Amur Oblast aboard a Soyuz-2 Fregat rocket on August 10, setting the vehicle on a swift trip to the moon.
Luna 25's trajectory allowed it to surpass India's Chandrayaan-3 lunar lander, which launched in mid-July, on the way to the lunar surface.
Media characterizations that India and Russia are racing for the lunar south pole, however, aren't entirely accurate, according to astrophysicist Jonathan McDowell, a researcher at the Center for Astrophysics, Harvard & Smithsonian. He pointed out that both projects have been in the works for more than a decade.
Safely landing a spacecraft on the lunar surface would mark a huge step for Russia's space program.
Luna 25 is also seen as a proving ground for future robotic lunar exploration missions by Roscosmos. Several future Luna missions are slated to make use of the same spacecraft design.
Russia is also seeking to prove that its civil space program, which some experts say has faced issues for decades, can still perform in high-profile, high-stakes missions.
"They were having a lot of problems with quality control, corruption, with funding," said Victoria Samson, the Washington office director for Secure World Foundation, a nonprofit that promotes the peaceful exploration of outer space.
CNN
