Each International Space Station crew flies as a trio to the outpost and back to Earth in a Soyuz spacecraft. About every three months, a crew returns to Earth shortly before a new one arrives, often leaving a few days when only three astronauts look after the Station.
Tim, Tim and Yuri will stay longer in space because ground control aims to keep the Space Station operating at full capacity with six astronauts.
Tim Peake says: “Although I am looking forward to being back on Earth and seeing friends and family again, each day spent living in space is a huge privilege and there is much work to do on the Station.
“This extension will keep the Station at a full crew of six for several days longer, enabling us to accomplish more scientific research.
“And, of course, I get to enjoy the beautiful view of planet Earth for a little while longer!”