··· And Facial Secrets

摘要

If you've ever wondered why almost all the dark lunar maria face Earth and the farside is covered almost entirely by highlands, an Icarus study by planetary dynamicists may have the answer. The Moon's globe is slightly oblong, like a football. One of the football's ends points straight at us and is crowded with lava-topped maria. The long axis points at us because, after the Moon formed, Earth's strong tidal forces created flexing and internal friction that gradually slowed the lunar spin.