Sławosz was selected in November 2022 as a member of the ESA astronaut reserve after a year-long selection process. The 2022 ESA recruitment campaign received more than 22 500 applications from across its Member States.

Sławosz joined the European Astronaut Corps on 1 September as an ESA project astronaut for the duration of his mission duties.

The Polish astronaut is following an intensive training familiarisation programme to meet the high standards required for spaceflight.

Sławosz, born in Poland in 1984, has a background in space systems engineering and has conducted research in radiation effects. He recently served as the Engineer in Charge of CERN's largest accelerator, the Large Hadron Collider.

“I'm very happy to get the chance and participate in ESA’s astronaut training familiarisation for a future spaceflight opportunity. Space has always been very close to my heart, and I've always considered myself a natural explorer. The past years have seen a massive push in developing technologies and research within low Earth orbit, so I’m looking ahead to extremely exciting times,” says Sławosz.