Mark Thomas Vande Hei (born November 10, 1966) is a retired United States Army officer and current NASA astronaut[2] who has served as a flight engineer for Expedition 53, 54, 64, 65, and 66 on the International Space Station.

[5] Vande Hei was commissioned in the U.S. Army through the ROTC program in 1989 and became a combat engineer, serving in Iraq in Operation Provide Comfort.

On June 10, 2014, NASA announced that Vande Hei would serve as an aquanaut aboard the Aquarius underwater laboratory during the NEEMO 18 undersea exploration mission, which began on July 21, 2014, and lasted nine days.

The expedition ended on February 27, 2018, at 9:31 p.m. EST with Vande Hei's, Bresnik's, and third crew member Joseph M. Acaba's successful landing back on Earth.

[3] In March 2021 it was confirmed that Vande Hei would be making a second spaceflight, as a flight engineer onboard Soyuz MS-18, and be part of ISS Expedition 64/65.

[12][13] On April 9, 2021, Vande Hei alongside Roscosmos cosmonauts Oleg Novitskiy and Pyotr Dubrov successfully launched onboard Soyuz MS-18 at 3:42 am EDT.

[16] Two weeks of technical and weather delays, together with Crew-2 approaching the maximum on-orbit duration of their Crew Dragon craft, forced a highly undesirable “indirect handover”.

[18] Shortly before his return to Earth, he passed 340 days in space, surpassing Scott Kelly as the record holder for the longest American spaceflight.

[19] He returned to Earth with Soyuz MS-19 on March 30, 2022, having spent a total of 355 days in space on a mission to better observe the effects of long-duration spaceflight on humans.

[26] Cosmonaut Anton Shkaplerov (commander) and the crew of the film The Challenge: actress Yulia Peresild and director Klim Shipenko went to the ISS onboard Soyuz MS-19.