Jupiter The Planet
Largest Planet In The Solar System

jupiter the planet

Jupiter the planet is fifth from the Sun and the largest planet in our solar system. Jupiter is so massive it's two and a half times the mass of all the other planets in our Solar System combined.

A "Jupiter mass" (MJ or MJup) is often used as a unit to describe masses of other objects, particularly extrasolar planets and brown dwarfs.

The first of the "outer" planets or gas giants, Jupiter is the fastest spinning of all the planets. Jupiter's day is less than ten Earth hours long.

The year on Jupiter is almost 12 Earth years long. That's less than half the time it takes Saturn the planet to orbit the Sun.

Jupiter spins so fast that like Saturn, it creates an equatorial bulge easily seen through an Earth-based amateur telescope.

Earth overtakes Jupiter every 398.9 days as it orbits the Sun, a duration called the synodic period. As it does so, Jupiter appears to undergo retrograde motion with respect to the background stars. That means for a period Jupiter seems to move backward in the night sky, performing a looping motion. jupiter the planet

Viewing Jupiter

Viewing Jupiter the planet can be quite rewarding. It is visible to the naked eye in the night sky and, can occasionally be seen in the daytime when the sun is low.

When viewed from Earth, Jupiter can reach an apparent magnitude of -2.94, making it on average the third-brightest object in the night sky after the Moon and Venus the planet. Mars can briefly match Jupiter's brightness at certain points in its orbit.

Favorable oppositions occur when Jupiter is passing through perihelion, an event that occurs once per orbit.

As Jupiter approaches perihelion in March 2011, there will be a favorable opposition in September 2010.

Because the orbit of Jupiter is outside the Earth's, the planet always appears nearly fully illuminated when viewed through Earth-based telescopes.

Surrounding the planet is a faint planetary ring system, though nothing as majestic as Saturn's and a powerful magnetosphere.

Jupiter The Planet In Telescopes

jupiter the planet

Jupiter is thrilling to view in just about any telescope, even a small department-store refractor will reveal several cloud belts and its four brightest moons.

The four largest moons, known as the "Galilean moons", are Io, Europa, Ganymede and Callisto. These were first discovered by Galileo Galilei in 1610. Ganymede, the largest of these moons, has a diameter greater than that of Mercury the planet. Jupiter has 63 named natural satellites. Of these, 47 are less than 10 kilometres in diameter and have only been discovered since 1975.

Jupiter is also one of the most dynamic telescopic sights — you never get the same view twice. This is partly the result of its rapid rotation.

Although Jupiter is big and bright, it doesn't tolerate high magnification well. Consequently, you will rarely use more than 40x per inch of aperture.

The four Galilean moons are easily visible with binoculars; a few bands and the Great Red Spot can be seen with a small astronomical telescope.

The Great Red Spot is a gigantic storm raging in the atmosphere of Jupiter. The storm is so large that almost 3 Earths could fit inside it. That's one huge hurricane.

There are many other storms raging in Jupiter's atmosphere. Sometimes they even crash into each other and create larger storms.

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