Expedition 51 crew members Fyodor Yurchikhin of Roscosmos, left, and Jack Fischer of Nasa hold up their toy mascots ahead of the April 2017 launch. Yurchikhin is holding several toys from his children and Fischer is holding an emblem of the MD Anderson Cancer Center in Houston, where his daughter, Sariah, was treated. Victor Zelentsov / Nasa
A red Angry Bird from the hit video game and film floats on board ISS. Russian cosmonaut Colonel Anton Shkaplerov took the toy on his 2011-12 mission. Anton Shkaplerov / Roscosmos
Col Shkaplerov then took Olaf from Disney's Frozen into space on his 2014-2015 mission. Anton Shkaplerov / Roscosmos
And he delighted fans with this poodle on his 2018 mission. In total he spent more than 530 days in space - and 14 hours floating outside the station on repair and expansion work. Anton Shkaplerov / Roscosmos
Smokey Bear floats on board ISS on May 15, 2012. Smokey travelled aboard the Soyuz spacecraft with Nasa astronaut Joe Acaba and Russian cosmonauts Gennady Padalka and Sergei Revin. The mascot is a recognised symbol for wildland fire prevention
SpaceX sent up this plush Earth toy aboard its Crew Dragon spaceship. Space station astronauts took a liking to the mascot and nicknamed him Earthy. US media reports say it subsequently sold out in stores around the country. Anne McClain / Nasa
Anne McClain took pictures of Earthy around the station, capturing wide interest on social media. Anne McClain / Nasa
At the Baikonur Cosmodrome in Kazakhstan, Expedition 52-53 crewmembers display toys from their children in front of the Soyuz MS-05 spacecraft. The toys are hung above the crew members’ heads to act as 'zero-g indicators'. Andrey Shelepin / Gagarin Cosmonaut Training Centre
At the Baikonur Cosmodrome in Kazakhstan in December 2012, Expedition 34/35 Soyuz Commander Roman Romanenko (centre) holds a toy 'talisman' that his nine-year old daughter, Anastasia, gave him to hang over his seat. He is pictured with Flight Engineer Tom Marshburn of NASA (left) and Flight Engineer Chris Hadfield of the Canadian Space Agency. Victor Zelentsov / Nasa
Nick Hague of Nasa, left, and Alexey Ovchinin of Roscosmos hold up their mascots in Oct 6 2012 during final fit check activities prior to launch. Victor Zelentsov / Nasa
In September 2012, Expedition 41 Soyuz Commander Alexander Samokutyaev and Flight Engineer Elena Serova of Roscosmos hold up tiger toys that will be carried with them to the International Space Station to commemorate International Tiger Day. Aubrey Gemignani / Nasa
Expedition 51 crew members Fyodor Yurchikhin of Roscosmos, left, and Jack Fischer of Nasa hold up their toy mascots ahead of the April 2017 launch. Yurchikhin is holding several toys from his children and Fischer is holding an emblem of the MD Anderson Cancer Center in Houston, where his daughter, Sariah, was treated. Victor Zelentsov / Nasa
A red Angry Bird from the hit video game and film floats on board ISS. Russian cosmonaut Colonel Anton Shkaplerov took the toy on his 2011-12 mission. Anton Shkaplerov / Roscosmos
Col Shkaplerov then took Olaf from Disney's Frozen into space on his 2014-2015 mission. Anton Shkaplerov / Roscosmos
And he delighted fans with this poodle on his 2018 mission. In total he spent more than 530 days in space - and 14 hours floating outside the station on repair and expansion work. Anton Shkaplerov / Roscosmos
Smokey Bear floats on board ISS on May 15, 2012. Smokey travelled aboard the Soyuz spacecraft with Nasa astronaut Joe Acaba and Russian cosmonauts Gennady Padalka and Sergei Revin. The mascot is a recognised symbol for wildland fire prevention
SpaceX sent up this plush Earth toy aboard its Crew Dragon spaceship. Space station astronauts took a liking to the mascot and nicknamed him Earthy. US media reports say it subsequently sold out in stores around the country. Anne McClain / Nasa
Anne McClain took pictures of Earthy around the station, capturing wide interest on social media. Anne McClain / Nasa
At the Baikonur Cosmodrome in Kazakhstan, Expedition 52-53 crewmembers display toys from their children in front of the Soyuz MS-05 spacecraft. The toys are hung above the crew members’ heads to act as 'zero-g indicators'. Andrey Shelepin / Gagarin Cosmonaut Training Centre
At the Baikonur Cosmodrome in Kazakhstan in December 2012, Expedition 34/35 Soyuz Commander Roman Romanenko (centre) holds a toy 'talisman' that his nine-year old daughter, Anastasia, gave him to hang over his seat. He is pictured with Flight Engineer Tom Marshburn of NASA (left) and Flight Engineer Chris Hadfield of the Canadian Space Agency. Victor Zelentsov / Nasa
Nick Hague of Nasa, left, and Alexey Ovchinin of Roscosmos hold up their mascots in Oct 6 2012 during final fit check activities prior to launch. Victor Zelentsov / Nasa
In September 2012, Expedition 41 Soyuz Commander Alexander Samokutyaev and Flight Engineer Elena Serova of Roscosmos hold up tiger toys that will be carried with them to the International Space Station to commemorate International Tiger Day. Aubrey Gemignani / Nasa
Expedition 51 crew members Fyodor Yurchikhin of Roscosmos, left, and Jack Fischer of Nasa hold up their toy mascots ahead of the April 2017 launch. Yurchikhin is holding several toys from his children and Fischer is holding an emblem of the MD Anderson Cancer Center in Houston, where his daughter, Sariah, was treated. Victor Zelentsov / Nasa