SMART-1 arrives at the Moon

"'We still don't know if the Earth and the Moon came from the same place,' says Manuel Grande, a space scientist at the Rutherford Appleton Laboratory near Oxford, UK, who is responsible for D-CIXS. Many scientists believe that the Moon was formed after a gigantic collision between a Mars-sized object and the Earth about 4.6 billion years ago. Comparing the ratios of different chemical elements on the Moon and Earth could confirm this theory, says Grande."