Current Moon Phase

Waning Crescent
1% of full

Farmers Almanac
The 2014 Farmers Almanac
Farmers' Almanac

Everything You Wanted to Know About Jupiter …

Everything You Wanted to Know About Jupiter …

Jupiter is usually the third brightest object in the night sky, after the Moon and Venus (only Mars, our next-door neighbor, is occasionally brighter), and summer is an especially good time to view this bright behemoth. Here are a few facts to think about as you look at the “Giant Planet” this summer:

- Jupiter is the fifth planet from the Sun and the largest planet in our Solar System. It is more than 1,000 times larger than the Earth, with a diameter of more than 88,846 miles at its equator.

- It takes Jupiter 4,332 Earth days, or about 12 years, to orbit the Sun. However, it rotates much faster than Earth, completing a whole day in only 10 hours.

- Jupiter was named for the Roman god Jupiter, who is also the Greek god Zeus, king of the gods. He is also known as Jove. In Norse mythology, the planet is associated with the thunder god, Thor.

- The first recorded sighting of Jupiter occurred more than 4,000 years ago. It can be seen in the night sky with the naked eye, and is even occasionally visible in the daytime, when the sun is low.

- Jupiter has at least 63 moons, the four largest of which are called the “Galilean moons,” because they were first discovered by astronomer Galileo Galilei in 1610. The largest, named Ganymede, is bigger than the planet Mercury. The other three are Io, Europa, and Callisto.

- Jupiter’s “Great Red Spot,” is actually a colossal storm that has been raging on the planet’s surface since at least the 17th century, when it was first seen by telescope. It is only one of many such storms on the planet’s surface.

- Though rings are more commonly associated with Saturn, Jupiter actually has a faint ring system.

- Jupiter is called a “gas giant” because, though it looks solid, it is made up primarily of gases, such as hydrogen and helium. It probably also has a rocky core comprised of heavier elements. Saturn, Neptune, and Uranus are also considered gas giants.

- Jupiter is only 30% smaller than the smallest known star, but because the gases on its surface are not very dense, it would need 75 times more mass to become a star.

- Jupiter has a very intense radiation field that reaches out more than 185,000 miles from the planet’s surface. This field is strong enough to damage spacecraft that travel too close. In addition, Jupiter’s gases produce almost as much heat as the planet receives from the Sun.

Now that you have a little more knowledge of this amazing planet, be sure to get outside on a clear night and look for it in the sky. No telescope required!

2 comments

1 Jaime McLeod { 07.02.10 at 11:07 am }

Hi Vickie,
Short of driving to Missouri and standing right next to you, there’s no way I can know for sure which star you mean. However, you’re probably looking at the planet Venus. After the Moon, Venus is usually the brightest body in the night sky, and it is sitting to the west right now.

2 vickie d. gilmore { 07.02.10 at 10:36 am }

I live inMissouri. Could someone please tell me what that very bright star is that I can see towards the west? Or tell me just what it is please.

Leave a Comment

Note: Comments that further the discussion of the above content are likely to be approved. Those comments that are vague or are simply submitted in order to promote a product, service or web site, although not necessarily considered "spam," are generally not approved.

If you notice a hole in the upper left-hand corner of your Farmers' Almanac, don't return it to the store! That hole isn't a defect; it's a part of history. Starting with the first edition of the Farmers' Almanac in 1818, readers used to nail holes into the corners to hang it up in their homes, barns, and outhouses (to provide both reading material and toilet paper). In 1910, the Almanac's publishers began pre-drilling holes in the corners to make it even easier for readers to keep all of that invaluable information (and paper) handy.