Jupiter shines bright in the night sky, so people have known about it since ancient times. The first detailed observations of this planet were made by Galileo Galilei in 1610 with a small, homemade telescope. Jupiter is the fifth planet from the Sun, and the largest in the Solar System.

Understanding the Context

It is a gas giant with a mass nearly 2.5 times that of all the other planets in the Solar System combined and slightly less than one-thousandth the mass of the Sun. It orbits the Sun at 5.20 AU with an 11.86-year period. Its diameter is 11 times that of Earth. After the Moon and Venus, it's the third-brightest object in Earth's night sky, observed since prehistoric times.

Key Insights

The planet is named after the chief Roman deity, Jupiter. Jupiter is the fifth planet from the Sun and the largest planet within the Solar System. It is a gas giant with mass one-thousandth that of the Sun but is two and a half times the mass of all the other planets in our Solar System combined.