Did We Have Two Moons? – Project GRAIL
– ” For You to Enjoy And Share With Friends” –
Some researchers believed we once had two moons. Nasa launched project GRAIL in September 2011 to investigate this theory and gather more information about the Moon. The two Lunar-orbiting Gravity Recovery and Interior Laboratory (GRAIL) spacecraft arrived in Moon orbit on 31st December 2011 and 1st January 2012. Over a period of three months they collected data which will take a year or so to analyse.
At the end of the initial data collection phase the two spacecraft were decommissioned and made ready for an extended mission which is taking place between August and December 2012.