A recent Russian rocket failure could make it necessary to leave the International Space Station (ISS) unmanned for a while, the National Aeronautics and Space Administration (NASA) admitted Monday.

If the reasons for the Soyuz capsule’s failure last week are not identified and solved by mid-November, all astronauts who are currently on the ISS will be brought back to Earth before their replacements can reach the station, NASA programme manager Mike Suffredini said Monday.

“We’re going to do what’s safest for the crew and the space station,” Mr. Suffredini was quoted as saying in the Houston Chronicle.

Since NASA’s own space shuttle fleet was grounded last month, the U.S. agency depends on Russian Soyuz capsules to transport its astronauts to the ISS.

Two astronauts among six in the ISS are American. Three astronauts are due to return to earth in September, with the remainder set to come back in mid-November.

NASA only completed its part of the ISS earlier this year, although it has had astronauts at the station for 11 years.

This story has been corrected for a factual error in the agency report.

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