Nasa's amazingly cool pictures of Earth or 'Blue Marble' started in 1972 when Apollo astronauts took photographs of our world from 28,000 miles away. The images that came back looked like a blue marble in space. Since then, the space agency has used the term for spectacular hi-def images of our planet created from satellite imagery and often released once a year. This is the latest photo they have captured using imagery from Nasa's most recently launched Earth-observing satellite, Suomi NPP.Blue Marble 2012 was taken by a hi-tech instrument aboard NASA's most recently launched Earth-observing satellite - Suomi NPP. This composite image uses a number of passes over the Earth's surface taken on January 4, 2012
