Ancient skywatchers gave the planets personalities. Jupiter, for example, represented the king of the gods of Olympus, with all the qualities that designation suggests — strength and courage, among others. If the modern world associated the planets with living beings, it might still be Olympians — but of the athletic kind. Mercury would be a sprinter, and Saturn a marathoner. And Jupiter would be king of the shot-put.
Jupiter is the giant of the solar system — it’s more massive than all the other planets put together. That gives it a powerful gravitational field, which has a big influence on the space around it.
When the solar system was young, it was filled with billions of small chunks of rock and ice known as planetesimals — the building blocks of planets. Jupiter’s gravity ejected many of them from the solar system, hurling them into deep space. Jupiter also pushed around the planetesimals in a broad band between Jupiter and the Sun, preventing them from forming a planet. Today, that band is the asteroid belt.
Jupiter continues to push around smaller bodies even now. Encounters with comets or asteroids can shove them into different orbits, and even kick them out of the solar system entirely — long-distance shot-puts for a true Olympian.
Jupiter rises to the lower left of the Moon in late evening, and is even closer to the Moon at first light tomorrow. The planet looks like a brilliant star. More about Jupiter and the Moon tomorrow.
Script by Damond Benningfield, Copyright 2013
For more skywatching tips, astronomy news, and much more, read StarDate magazine.