tidal forces

"Summer ends, and Autumn comes, and he who would have it otherwise would have high tide always and a full moon every night." -Hal Borland Of course you know the danger that would befall us if the Earth ever got too close to the Sun, as the Perry Bible Fellowship shows, atop. But have you ever stopped to think about the Moon in our skies, and what would happen if the Earth and Moon were closer together than they actually are? Image credit: NASA / Galileo mission. While photos such as this -- from the Galileo spacecraft -- accurately show the relative size and illumination of the Earth and…
The patterns of the dark craters on the near side of the Moon have spurred the imagination of observers from all cultures: Some visualize a woman, others a rabbit, or, like most of us, they see the "Man in the Moon." Near side The explanation as to why we always see the Man in the Moon - that is, why we only see one side - is that tidal forces caused the Moon to slow its spin until it reached the present point. It now takes the same amount of time to rotate around its own axis as it does to revolve around Earth. It is this synchronous rotation that causes the moon to "lock" with Earth, with…