Moon transiting the Sun from the SDO. Image of the Moon passing in front of the Sun as seen from NASA's Solar Dynamics Observatory (SDO). The SDO is an Earth-orbiting spacecraft launched in 2010 by NASA and used to observe the Sun. It orbits the Earth in a geosynchronous orbit. This motion around the Earth, combined with the motion of the Moon around Earth and the Earth around the Sun creates opportunities for it to view transits in the same way as the Earth itself views them due to its motion. Imaged on 11th March 2013.