Mercury is the smallest and innermost planet in the Solar System. But here’s a question, how did Mercury get its name?
Like all the planets, Mercury is named after one of the Roman gods, which were based on the gods worshipped by the Ancient Greeks. The Roman god Mercury was the son of Maia Maiestas and Jupiter in Roman mythology, and most of his aspects were based on the Greek god Hermes.
According to mythology, Mercury was the swiftest of the gods, and the one that merchants prayed to for success in their commercial transactions. And Hermes was known as the messenger of the gods in Greek mythology. This is appropriate since Mercury is the innermost planet in the Solar System, and appears to move quickly from night to night.
Since Mercury was visible with the unaided eye, most of the ancient cultures had their own name for Mercury. The ancient Babylonians called the planet Napu, after a god in their mythology. The ancient Greeks actually thought that Mercury was two planets, and they called it Apollo when it was visible in the morning sky, and Hermes when it was seen after sunset. But in the 4th century BCE, ancient astronomers realized that the two objects were one and the same, and stuck with Hermes; becoming Mercury with the Romans.
And that’s how Mercury got its name.
We’ve also recorded an entire episode of Astronomy Cast all about Mercury. Listen here, Episode 49: Mercury.