ESA title
Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Astronaut

Sławosz Uznański

Sławosz Uznański-Wiśniewski was selected in November 2022 as a member of ESA's astronaut reserve. He officially joined ESA as a project astronaut on 1 September 2023, beginning his training and familiarisation at the European Astronaut Centre in Cologne, Germany. He was later assigned to Axiom Mission 4 (Ax-4) and launched to the International Space Station on 25 June 2025 for a short-duration mission.

Biography

About Sławosz

During his doctorate, Sławosz worked as a radiation effects engineer at STMicroelectronics focusing on the next European radiation-tolerant and radiation-hardened digital CMOS technologies for space applications in Crolles, France.

In 2011, Sławosz joined the European Organization for Nuclear Research (CERN) in Geneva, Switzerland, working as a reliability expert. His duties included for example leading radiation test campaigns in ESA test facilities to qualify electronics components and systems for space and accelerator use.

In 2013, he was appointed as a project lead and senior reliability engineer at CERN where he was in charge of the creation of a radiation-tolerant power converter control system which has been a core part of the Large Hadron Collider LHC since 2017.

From 2018 to 2020, he was an Engineer in Charge of LHC, being responsible for the day-to-day 24/7 operations of CERN’s largest accelerator and assuring its optimum exploitation.

In 2019, he was serving as a technical expert and evaluator for the EU's research and innovation funding programme Horizon 2020 reviewing European space technologies for the Research Executive Agency (REA) at the European Commission in Brussels, Belgium.

Alongside his professional career, Sławosz’s interests have always been closely related to space applications. He lectured on space system designs for international schools of engineers SERESSA 2014 and 2021 (School on the Effects of Radiation on Embedded Systems for Space Applications) and organised workshops between CERN and NASA as well as workshops for the private sector.

He has authored a book on radiation effects, numerous publications and organised multiple international scientific workshops and lectures. From 2014, he was also an active volunteer reviewing multiple commercial space satellite projects such as the ICEYE constellation as well as Polish space missions like PW-SAT2, HyperSat and EagleEye.

On his days off, Sławosz is outside testing his limits on high-altitude mountaineering expeditions, travelling to remote places or on a sailing boat, enjoying time with friends, sharing his sailing experience or taking part in competitive regattas.

Education

Sławosz graduated with honours with a master's degree from the Technical University of Łódź, Poland, in 2008 and a master's degree from Université de Nantes, France, in 2008. In addition, he received a Diplôme d’Ingénieur from École Polytechnique de l'Université de Nantes, France, in 2008.

In 2011, Sławosz earned his Doctorate in radiation-tolerant designs for space applications from the Université d’Aix-Marseille, France.

Next to his mother tongue Polish, Sławosz also speaks English and French.

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ESA missions

1

The Polish project astronaut is the second of a new generation of European astronauts to fly on a commercial human spaceflight opportunity with Axiom Space. Sponsored by the Polish government and supported by ESA, the Polish Ministry of Economic Development and Technology (MRiT), and the Polish Space Agency (POLSA), the mission will include an ambitious technological and scientific programme with several experiments led by ESA and proposed by the Polish space industry.

Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Inside Ignis: the ground team powering spaceflight

Leider ist der Eintrag nur auf English verfügbar.

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Get your Ignis wallpaper

(English) Bring the spark of Ignis to your screen with official Ignis wallpapers.

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Mid-mission update: Sławosz’s first week on the Space Station

(English) The Axiom Mission 4 (Ax-4) crew arrived safely at the International Space Station on 26 June 2025. Since then, ESA project astronaut Sławosz Uznański-Wiśniewski has hit the ground—well, the microgravity—running, diving straight into science, education and outreach as part of this packed two-week mission. 

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) A new adventure on the International Space Station

(English) Watch the highlights of a new adventure on the International Space Station as ESA project astronaut Sławosz Uznański-Wiśniewski begins the Ignis mission.

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Ignis ignited

(English) ESA project astronaut Sławosz Uznański-Wiśniewski has officially begun his first space mission, entering the International Space Station on 26 June 2025. He is pictured here among the now 11-member crew on board the Station, representing six different countries, shortly after the arrival of Axiom Mission 4 (Ax-4).

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Liftoff of Axiom Mission 4

(English) The Axiom Mission 4 (Ax-4) crew lifts off to the International Space Station atop a SpaceX Falcon 9 rocket from launchpad 39A at NASA’s Kennedy Space Center in Florida, USA, on 25 June at 07:31 BST/08:31 CEST (02:31 local time).

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Astronaut portrait - Sławosz Uznański. Credits: ESA - A. Conigli
Sławosz Uznański

(English) Countdown to Ignis

(English) As the countdown to Axiom Mission 4 (Ax-4) enters its final phase, ESA project astronaut Sławosz Uznański-Wiśniewski has completed an intensive training programme across the globe. Scheduled to launch no earlier than 8 June 2025, Ax-4 will take him and his crewmates to the International Space Station for a two-week mission focused on science, technology and international collaboration.

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