Jupiter, Bringer of Joy

See Pictures of Jupiter

Jupiter is the 5^th planet from the Sun and is the largest planet of the Sun's system. The most conspicuous sign of Jupiter is the Great Red Spot. This huge hurricane, or cyclone, has been on the planet for hundreds with winds as high as 400 miles an hour of years and shows no signs of slowing down. Another hallmark of this planet is its multilayered color variation. Even though the colors are bland, the patters and shades of the clouds on this planet are strikingly beautiful, much like the layers of color in the grand canyon. Jupiter has at least 61 satellites (Go to Jovian Satellites page). Galileo observed four of these satellites (Io, Europa, Callisto and Ganymede) and these are called the Galilean moons.

Although Jupiter is 1400 times larger than the Earth, it has a density only 1/4^th that of the Earth. It's atmosphere is composed mainly of hydrogen and helium, but has traces of methane, water and ammonia. Crystals of methane and ammonia cause the colors of Jupiter's clouds. Jupiter has such as high mass and such high internal pressure that it theoretically has a metallic hydrogen and helium core. This gives Jupiter a high strength magnetic field which would fry most electronics.

Many astronomers call the giant planet our neighboring solar system vacuum cleaner. This explanation is not too far off the mark either. Since the planet lies outside the orbit of earth, and since it's size gives it tremendous gravitational force, it can influence the path of run-away asteroids and comets before they pummel into the inner planets. Jupiter has altered orbits of innumerable objects, saving our planet and the other inner planets from many massive collisions. One of the most recent and spectacular was the collision of a newly discovered comet, Shoemaker-Levy 9.  David Levy and other amateur astronomers found this comet on April 15, 1994 and quickly learned that the comet would be on a collision course with the great planet. Starting on July 16, 1994 nearly every telescope in the world was aimed at the goliath and captured pictures of the most violent collisions witnessed by man in recorded history (see pictures on Jupiter picture page).

It was the Jovian system that gave the final proof of Solar centricity that was foretold by Copernicus and had been mathematically proven through the work of Johannes Kepler and Tycho Brahe. In 1609, Galileo trained a homemade telescope to the sky and observed the sky in all of it's glory. He patiently observed the planets night after night and learned that Venus goes through phases like the moon and Jupiter had small moons like the Earth's moon. Many in Galileo's time believed that the Earth could not move in an orbit because the moon would be left behind. Galileo discovered that the moons of Jupiter kept up with their planet. These two findings proved once and for all that the Earth was not the center of the universe. Geo-centricity, that is the belief that the Earth is the center of the universe, was a long held Catholic belief that faced Galileo off with the Pope in the first great battle of religion and science. Take a guess who won! Which name do you remember, Pope Paul V or Galileo?

There have been several missions to Jupiter. Voyager 1 and 2 passed close to this planet and brought us our most detailed imaged up to that time. Voyager 1 discovered evidence of a ring around the planet, and Voyager 2 confirmed this finding with a dark side shot of the planet.  A more recent mission was the Galileo mission where a probe was allowed to descend into the atmosphere and take samples and other data for astronomers back on earth. 

Jupiter has many attributes that make it an awesome object. It is a great object when viewed under the weakest of optical telescope in use by amateurs everywhere.

An A.U. is the distance from the sun to the earth (9.3x10⁷ miles). Oblateness is the fraction by which the equatorial diameter exceeds the polar diameter. Albedo is the fraction of light reflected off of an object.