How long does a space mission last?

Short answer

The current standard is a rotation of about six months aboard the International Space Station. But the range is wide: Yuri Gagarin's flight, on 12 April 1961, lasted 108 minutes, while Valeri Polyakov stayed 437 days aboard the Mir station, a record never broken since.

Published: September 24, 2026 · Updated: September 24, 2026 · Edited by Above Ten Thousand · Editorial policy

Expedition 23 Landing

There is no standard length for a crewed flight: the question of time spent in orbit has shifted as objectives have changed. We have gone from a single-orbit round trip to stays lasting months, then to very long-duration experiments meant to prepare for distant voyages.

From 108 minutes to 437 days

The first crewed flight, Yuri Gagarin's on 12 April 1961, lasted 108 minutes, the time for one trip around the Earth. At the other end of the spectrum, Russian physician Valeri Polyakov stayed 437 days aboard the Mir station in the 1990s. Between these two extremes lie the Apollo lunar flights, measured in days, shuttle flights, measured in one to two weeks, and station stays, measured in months.

Why six months

The six-month crew rotation is not arbitrary. It results from how long a spacecraft can safely remain docked, the pace of relief launches, the radiation dose deemed acceptable, and a crew's ability to remain effective far from their loved ones. Extensions do happen: when a returning spacecraft runs into trouble, a stay can stretch well beyond the original plan.

The return of short flights

Private missions docked to a station last only days, and suborbital tourist flights last minutes: the latter cross the boundary of space without ever reaching orbit. Future crewed flights to the Moon will return to durations of a few days to a few weeks, very different from the rhythm established in low Earth orbit.