The Grail and the Moon

Gary Gilligan sent in this link to a story about NASAs Grail mission which is set to blast off in an attempt to unravel some of the mysteries of the Moon (see http://science.nasa.gov/science-news/science-at-nasa/2011/07sep_twomoons/ – and one such mystery concerns a paper in Nature that claimed there was once two moons orbiting the earth. The small of the two struck the bigger one and created the bumps and humps on the far side of the Moon. The current consensus is that a Moon sized object crashed into the Earth around 4 billion years ago and the cloud of debris coalesced to form the Moon. Hence, it is possible it formed two bodies – but it all sounds a bit like Worlds in Collision (and these are mainstream scientists too).