ESA astronaut Alexander Gerst took this image circling Earth on the International Space Station during his six-month Blue Dot mission.
Alexander commented: "The big picture. I begin to understand how flying into space will change humankind's way of looking at Earth forever."
Read more about the Blue Dot mission at http://www.esa.int/Our_Activities/Human_Spaceflight/Blue_dot
Follow Alexander via alexandergerst.esa.int