A SpaceX capsule docked at the International Space Station

The four men, three Americans and one German, replaced the crew 2 that left the International Space Station on Monday, including France’s Thomas Pesquet.

NASA astronauts Raja Chari, Kayla Barron, Tom Marshburn and European Space Agency astronaut Matthias Maurer blasted off from Florida with a SpaceX Falcon 9 rocket on Wednesday evening, and the liftoff was postponed several times, especially due to the weather.

For American Tom Marshburn, this is the third flight in space. He actually flew on a space shuttle in 2009, and then a Soyuz rocket in 2012-2013.

On the other hand, the other three astronauts, including chief of mission Raja Chari, made the first flight.

Matthias Maurer is the 12th German to end up in orbit.

They were greeted by American Mark Vandy, who celebrated his birthday on Wednesday alone in the American part of the station. Also on board are two Russian cosmonauts.

The mission is called Crew-3 because it is the third operational operation for the International Space Station that SpaceX is offering on behalf of NASA.

But this is actually the fifth time Elon Musk has launched humans into orbit: Before Crew-1 and Crew-2, the Demo-2 test mission sent two astronauts to the International Space Station. And in September, SpaceX also launched four tourists for three days in space, independently of NASA.

The assignment will involve many experiences. One is to grow plants in space without soil or other growing medium, and the other is to build microgravity optical fibers that can be of higher quality than those made on Earth.

Crew 3 astronauts will also conduct spacewalks, in particular to continue installing new solar panels on the International Space Station.

Finally, they will host two tourist missions: the Japanese brought by the Russian Soyuz spacecraft at the end of the year, and then in February 2022 a passenger from the Ax-1 mission, organized by Axiom Space in partnership with SpaceX.