Why Is Jupiter Named Jupiter?

Who was the Roman god Jupiter?

The king of the Roman gods. Jupiter was the god of the sky, thunder, and storms, and the patron deity of the Roman state. He was the equivalent of the Greek god Zeus, and many of his myths were adapted from earlier Greek traditions. Jupiter was associated with lightning bolts, eagles, and oak trees. As king of the gods, he was the most powerful figure in the divine hierarchy.

Why was the planet named after him?

Because it's the biggest. Jupiter is the largest planet visible to the naked eye, far brighter and more prominent than Mars or Saturn. To ancient Roman astronomers, the planet's size and brilliance suggested the most powerful god in their pantheon. Jupiter also moves slowly through the sky compared to closer planets, which the Romans interpreted as the stately motion of a king. The naming made obvious sense given the brightness and grandeur of the planet as seen from Earth.

How did other cultures name Jupiter?

Almost always after a major deity. The Greeks called it Zeus, also their king of the gods. The Babylonians called it Marduk, after their chief deity. The Hindus called it Brihaspati, the guru of the gods. The Norse associated it with Thor, the god of thunder. The Chinese called it Sui Xing, the Year Star, because Jupiter completes its orbit in roughly 12 years and was used as a marker for years. The pattern across cultures is striking: nearly everyone identified Jupiter as the most important wandering body in the sky.

Does Jupiter's name fit the planet?

Remarkably well. The Romans named Jupiter for being the biggest planet, but they couldn't have known how appropriate the choice was. Jupiter really is the king of the planets: more massive than all the others combined, with the strongest gravity and magnetic field. Jupiter acts as a gravitational shepherd for the rest of the solar system, influencing the orbits of asteroids, comets, and other planets. The name fits.