Chris Hadfield: Around Planet Earth in 1,500 tweets
Canadian astronaut Chris Hadfield is due to return to Earth on Tuesday from a five-month stint on board the International Space Station.
Since docking with the ISS in a Soyuz craft in December, the 53-year-old station commander has kept hundreds of thousands of followers back on Earth informed and entertained from orbit.
He has tweeted from the space station at least 1,500 times, capturing remarkable images of many corners of the world.
His first photograph came in his first tweet from the ISS: "Space Station! Floating free, buoyed up even more by my smile :)"
His first days were marked by a series of photos detailing life inside the space station.
But he soon branched out into striking orbital landscapes of the planet below.
We have collected just a few of Cmdr Hadfield's tweeted shots and captions here - more are available by browsing his Twitter feed @Cmdr_Hadfield.
The photographs of @Cmdr_Hadfield
A former fighter pilot, Chris Hadfield became a trainee astronaut in 1992 after winning selection from a field of 5,330 applicants, according to Nasa.
He flew on board the space shuttle, docking with the Russian space station Mir and as part of an assembly flight to the ISS in 2001.
He eventually won his own slot on board the ISS in 2010, training for his current mission until lift-off in December 2012.
After gathering hundreds of thousands of Twitter followers during his months on board, he made one final hit as the time came for his departure from the ISS.
He posted a striking video to YouTube of him performing a version of David Bowie's renowned 1969 hit song Space Oddity.
The video quickly went viral, and even prompted a response from Bowie's own official account: "Hallo Spaceboy..."