Three astronauts returned safely to Earth aboard a spacecraft with a hole in it.

The Russian-made Soyuz MS-09 spacecraft carrying three astronauts landed in a vast snow-covered area in Kazakhstan, about 140km southeast of the city of Dzhezkazgan, on December 20.

Volunteers care for the astronauts upon their return. Photo: AFP

The astronaut team included Serena Aunon-Chancellor from NASA, Sergey Prokopyev from the Russian space agency (Roscosmos), and Alexander Gerst from the European Space Agency – who spent 197 days on the ISS serving on Expeditions 56 and 57 missions.

The return of the three astronauts was mandatory when, last August, they discovered a 2mm hole in the upper part of the Soyuz MS-09 spacecraft, causing the air pressure inside to gradually decrease.

Scientists believe the cause may have been a collision between Soyuz MS-09 and a super-meteorite. However, the team of experts from the Russian Space Agency does not rule out the possibility that the hole was deliberately drilled by someone.

"This could be a manufacturing defect, but it could also be an intentional act," Dmitry Rogozin, head of Roscosmos, told the media, adding that he would participate in the investigation once the spacecraft returned to Earth.

If this flaw had gone undetected, the astronauts could have run out of oxygen within 18 days.

Luckily, it was discovered. The astronaut team then repaired it in a makeshift manner and immediately returned. Fortunately, the journey was safe.

NASA stated that the astronauts had traveled 3,152 times around the Earth, covering a distance of over 134 million kilometers, and conducted over 300 scientific experiments during their six-month mission.

A hole has appeared on the Soyuz MS-09 spacecraft. Photo: NASA

The image shows the spacecraft carrying the astronauts after it landed. Photo: Reuters

Locals welcomed the astronauts and held a small party to celebrate. Photo: Reuters