The Moon moves away from us every single year.
The Moon moves away from us every single year — about 3.8 centimetres, roughly the rate your fingernails grow. It doesn't sound like much, but the effect adds up across geological time. The culprit is tidal friction. As the Moon's gravity pulls at Earth's oceans, it acts as a slow brake on our planet's spin. That energy has to go somewhere, so it gets transferred outwards, nudging the Moon into a slightly wider orbit. The consequence is that our days are growing longer, so gradually you'd never feel it in a lifetime. Hundreds of millions of years ago, a day on Earth lasted only around 22 hours. And far enough into the future, the Moon will sit so distant in the sky that total solar eclipses simply won't happen anymore. A perfect alignment, lost to time. Follow Deep Field Vault for more of the universe.