Here Is The Longest Time Any Human Has Spent In Space, Both Consecutive And Cumulative Days
When NASA astronauts Sunita Williams and Barry Wilmore finally returned to Earth in March, they had spent 286 days in space. Not willingly, however, as a string of technical delays kept prolonging their stay aboard the space station. In doing so, the duo also set the record for the longest unplanned continuous stay in space. Spending over nine months in zero gravity is no small feat, but their journey was not the longest spaceflight mission of its kind.
In fact, it was not even the longest recorded continuous stay in space, or even the combined highest number of days. Even among NASA's ranks, the pair stands behind several trailblazers, some of whom spent almost a whole year living aboard the space station, conducting scientific experiments. Interestingly, the record holder for the longest single mission in space clocked nearly double the number of days compared to some of NASA's record-holders.
The record holder in question is Russian cosmonaut Valeri Polyakov, who passed away in 2022 at the age of 80, and had spent over a year and two months in space. After spending a long time in space, physical weakness is a given. Interestingly, when Polyakov returned, he walked from his capsule and sat on a seat, all on his own. "He also stole a cigarette from a friend nearby, but could hardly be blamed for that. He sipped a small brandy and inwardly celebrated his mission," writes Philip Baker, in his book titled "The Story of Manned Space Stations."
Longest single-mission stay in space
Polyakov spent 437 days floating in the Earth's orbit aboard the Mir space station. Here's the most audacious element of his journey. Polyakov achieved the feat back in 1995, back when space stations lacked the cutting-edge exercise machines that are now tasked with keeping astronauts in shape. When he returned from his long stay, NASA astronaut Norman Thagard noted that Polyakov looked bulky and strong, almost as if "he could wrestle a bear."
Notably, Polyakov was an expert in the field of astronautics medicine. It might come as a surprise that before he even embarked on his record-breaking space odyssey, Polyakov had already logged 240 days in space for a single mission that was launched in 1988 aboard the Soyuz TM-6 spaceflight headed to the Mir Space Station.
Behind Polyakov is Russian astronaut Sergei Avdeev, who spent 380 days on a single spaceflight mission to the Mir Station. The third spot is jointly held by Oleg Kononenko and Nikolai Chub, who spent a record 374 days aboard the ISS and returned in 2024. For the fourth spot, the honor is shared among NASA's Francisco Rubio, alongside Russia's Sergey Proopyev and Dmitry Petelin, at 371 days. Among NASA's ranks, the single longest mission is credited to Francisco Rubio at 371 days, with Butch Wilmore and Sunita Williams' 289-day sojourn coming in joint sixth.
Longest cumulative stay in space
When it comes to the longest cumulative stay in space, we are not talking about months. The scale, in this case, extends to years. Take, for example, the current record holder, Oleg Kononenko. Spanning across five spaceflight missions, the Russian cosmonaut spent a staggering 1,111 days in space. For perspective, that's over three years spent orbiting our home planet. When Kolonenko returned to Earth late in 2024, he had also set a record for the longest single-mission stay on the space station at 374 days, an honor he shared with fellow cosmonaut Nikolai Chu.
Kononenko is also the first person to have spent over a thousand days in space. "My entire life is flying. Flying in space," Kononeko told NASA. "I realize the vector was always pointed towards space." The milestone might seem like just another figure, so here is an alternative look at its staggering depth. While in space, Olonenko made over 16,000 orbital trips around the Earth. In terms of distance, he has flown over 420 million miles, enough for a one-way trip to Jupiter.
In the second spot is Russia's Gennady Padalka with 878 days spent away from Earth. Next in line is fellow cosmonaut Yuri Malenchenko, who logged 827 days in space. Yuri Malenchenko also holds the record of being the first person to get married in space, involving a cardboard cutout of the cosmonaut used for the on-Earth ceremony. Behind him are Sergey Krikalyov (803 days) and Alexander Kaleri (769 days).