Science
Why is Earth the only planet not named after a god?
- Nobody saw it as a planet
- The name is older
- It was renamed
The answer is Nobody saw it as a planet. For most of history it was not a planet at all - just the ground.
Because for almost all of history it was not a planet. The word planet comes from the Greek for wanderer, and described the handful of lights that moved against the fixed stars - Mercury, Venus, Mars, Jupiter, Saturn, and often the Sun and Moon. The ground you stand on was not one of them; it was the centre, and the thing everything else moved around.
So it never needed a divine name, and the one it has is simply the old word for soil. Earth comes from Old English eorthe, and the equivalents in other languages do the same thing - terra, tierra, aarde. It is the only planet whose English name is Germanic rather than Roman.
It only joined the club in the sixteenth century, when Copernicus put the Sun at the centre and the ground became one wanderer among several. By then the naming convention was set and nobody was going to rename the world. Uranus, discovered in 1781, nearly broke the pattern too: its finder William Herschel wanted to call it George's Star after his patron, which the rest of Europe declined to adopt.