A veteran of five Space Shuttle flights and seven spacewalks, Parazynski's latest mission was STS-120 in October 2007 – highlighted by a dramatic, unplanned extra-vehicular activity (EVA) to repair a live solar array.

His passion and determination continue to inspire, exemplified by the lasting impact he had on a friend of his son, Luke, who once spoke to Parazynski during a space mission—a moment that left a lifelong impression.

[6] He subsequently founded Fluidity Technologies[7] based on his intellectual property, a company aiming to manufacture and distribute novel control devices for mobility in 3-D space, for everything from drones and computer games to VR and surgical robotics.

While in medical school, he competed on the United States Development Luge Team and was ranked among the top ten competitors in the nation during the 1988 Olympic Trials.

While an undergraduate at Stanford University, Parazynski studied antigenic shift in African sleeping sickness, using sophisticated molecular biology techniques.

Additionally, he has been involved in the design of several exercise devices that are being developed for long-duration space flight, and has conducted research on high-altitude acclimatization.

Parazynski initially served as one of the crew representatives for extra-vehicular activity (EVA) in the Astronaut Office Mission Development Branch.

Following his first flight, he was assigned as a backup for the third American long-duration stay aboard Russia's space station Mir, and was expected to serve as a prime crew member on a subsequent mission.

The fourth EVA is considered one of the most challenging and dangerous ever performed: while perched on the end of a 90-foot robotic boom, further away from the safety of the airlock than anyone had previously ventured, he had to repair a fully energized solar array.

ATLAS-3 was part of an ongoing program to determine the Earth's energy balance and atmospheric change over an 11-year solar cycle, particularly with respect to humanity's impact on global-ozone distribution.

He and his crewmates also successfully evaluated the Interlimb Resistance Device, a free-floating exercise he developed to prevent muscular atrophy in microgravity.

Highlights of the mission included the exchange of U.S. crew members Michael Foale and David Wolf, the transfer of 10,400 pounds of science and logistics, and the first Shuttle-based joint American-Russian spacewalk.

Parazynski (EV1) and Russian cosmonaut Vladimir Titov performed a 5-hour, 1 minute spacewalk during which they retrieved four experiment packages first deployed during the STS-76 Shuttle-Mir docking mission.

In addition, he was responsible for monitoring several life sciences investigations, including those involving crewmate Senator John Glenn.

Additionally, the pair installed a new UHF radio antenna for space-to-space communications during Space Shuttle rendezvous and ISS extravehicular activity.

Also during the flight, Parazynski operated Endeavour's robotic arm to attach, and later detach, the Italian-built Raffaello Multi-Purpose Logistics Module.