Canadian Chris Hadfield and his American colleague Thomas Marshburn left Earth on December 19 as astronauts, but they return as internet celebrities.
Exhibition 35 of the International Space Station came to an end today, ending five months of amazing photos of our planet taken by the two astronauts which have been shared on social media by hundreds of thousands of fans.
Hadfield, Marshburn and Russian cosmonaut Roman Romanenko landed as planned southeast of the town of Dzhezkazgan at 8:31am local time (2.30pm NZT) following a-146 day mission to the International Space Station.
Watch the livestream of the spaceship's landing here.
The undocking marked the start of Expedition 36 under the command of Russian cosmonaut Pavel Vinogradov, who will remain at the station with Chris Cassidy and Alexander Misurkin.
Live footage on NASA TV showed the Soyuz TMA-07M capsule slowly descending by parachute on the sun-drenched steppes under clear skies. Russian search and rescue helicopters were hovering around the landing site for a quick recovery effort.
Hadfield and Marshburn have attracted a massive following on social media; Marshburn has almost 40,000 followers on Twitter , while Hadfield has a whopping 850,000 followers on Twitter and another 270,000 on Facebook.
Hadfield in particular has embraced social media, posting scores of videos on Youtube sharing life aboard the ISS and also partaking in a Reddit "Ask Me Anything" live chat.
A highlight from Hadfield came yesterday, when he posted a polished video performance of David Bowie's Space Oddity sung by Hadfield while orbiting Earth.
The video has already had more than 1.5 million views.
Bowie described the cover as "possibly the most poignant version of the song ever created".
Hadfield's astronomical rise in popularity came on the back of a Twitter conversation in January with four of the most famous names associated with space travel - the second man on the moon, Buzz Aldrin, and Star Trek's William Shatner, George Takei and Leonard Nimoy.
The following month the Canadian Space Agency live streamed a video conversation between Hadfield and fellow Canadian Shatner.
Hadfield and Marshburn have boosted public interest in space and science, and engaged with the public like few astronauts before them, at a time when both the Canadian Space Agency and NASA have seen a cut in funding.
The five-month mission has not just been about tweets and videos clips, it has also been productive scientifically, with the Expedition 35 crew achieving the most hours of science in a single week ever performed on the space station. Read more about the research work on the ISS here.
Fans of Hadfield and Marshburn on social media will hope either Vinogradov, Cassidy or Misurkin pick up where they left off, although none of them appear to have a Twitter account at this stage.