Astronaut's incredible year in space
After spending a whole year in space, astronaut Scott Kelly is returning to Earth.
His identical twin, Mark Kelly, stayed on Earth during the year. American space agency Nasa is carrying out research on both men to see how a year of weightlessness affects the human body.
The research is important as it will take a year of space travel to reach Mars.
While on the International Space Station, Scott Kelly shared fantastic images of our planet on social media, as well as videos showing every day life in space.