A MYSTERIOUS bulge on the far side of the moon is providing clues to its exotic orbit billions of years ago.
Our moon is thought to have formed after a Mars-sized body smashed into Earth some 4.5 billion years ago. The collision sprayed molten debris into space, which then clumped together and eventually solidified to form the moon at a distance of about 4 Earth radii from the Earth’s centre. Over billions of years, the moon spiralled outwards to its present nearly circular orbit at about 60 Earth radii. Because its spin period is equal to its orbital period, one…
