German Astronaut Alexander Gerst Aboard The International Space Station

IN SPACE - OCTOBER 7: (EDITORIAL USE ONLY) In this handout photo provided by the European Space Agency (ESA), German ESA astronaut Alexander Gerst takes a 'selfie' during his spacewalk, whilst aboard the International Space Station (ISS) on October 7, 2014 in Space. Gerst returned to earth on November 10, 2014 after spending six months on the International Space Station completing an extensive scientific programme, known as the 'Blue Dot' mission (after astronomer Carl Sagan's description of Earth, as seen on a photograph taken by the Voyager probe from six billion kilometres away). (Photo by Alexander Gerst / ESA via Getty Images)