Sławosz Uznański‑Wiśniewski

Born in 1984, Sławosz Uznański‑Wiśniewski grew up in Łódź, Poland, where an early fascination with space developed alongside a passion for science and outdoor adventure. From mountain climbing to racing sailing boats with Poland’s national team, he built the determination that later guided his path as an astronaut. He studied engineering in Poland and France and earned a doctorate specialising in radiation‑tolerant designs for space applications. Sławosz’s professional career led him to CERN, where he headed radiation‑related reliability projects and lead the design of the power (or power converter) control system for the Large Hadron Collider. He also took part in European space technology evaluations and volunteered on several Polish satellite initiatives. Selected in November 2022 from more than 22,500 applicants, he joined ESA’s new astronaut class as part of the European Astronaut Reserve. On 1 September 2023, he became an ESA project astronaut and began training at the European Astronaut Centre in Cologne. Assigned to Axiom Mission 4, Poland’s first government‑supported scientific and technological mission (IGNIS) to the International Space Station, he trained with Axiom Space, NASA, SpaceX and JAXA. Sławosz launched on 25 June 2025 aboard a SpaceX Dragon, becoming the second Polish citizen in space. The IGNIS mission ended on 15 July 2025. Across 20 days, he completed nearly 320 Earth orbits, around 120 hours of work on the International Space Station and executed more than 20 scientific experiments and technology demonstrators, marking a milestone for Poland in human spaceflight.