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The Planet Jupiter And Its Moons


In early June the planet Jupiter ascends slowly into the southeastern evening sky. This beige colored planet is easy to see because it is the brightest object in the night sky except for the moon.

Jupiter is the largest planet in our solar system and the fifth from the sun. On January 7, 1610 Italian astronomer Galileo Galilei turned his very modest telescope towards Jupiter and noticed three stars lined up closely to the planet. When he looked at Jupiter later on January 10 he noticed a fourth star and that the other stars had moved from their fixed positions. It was from these observations that Galileo was able to deduce that Jupiter was like a miniature solar system and that the four stars were moons orbiting Jupiter much like our earth and other planets orbit the sun. Besides our own moon, the moons of Jupiter were the first discovered in our solar system. A total of 79 moons have been found to orbit the planet Jupiter.

If you own a pair of binoculars or a small telescope you can see Jupiter’s disk and its four associated moons. If you watch the moons over several nights you will notice a different arrangement of the moons each time. Jupiter will be visible in the evening sky from early June to mid October.