Jupiter

Did you know that Jupiter's storm has been brewing over 400 years? Find out the history and nature of Jupiter's Big Red Spot.

Jupiter's Spot has been visible for 300 years, but only now are we beginning to understand it.

The Spot is, basically, a storm. It is a swirling gas mass of extremely cold temperatures. What's more, its twice as large as the planet earth. Many speculations have been made as to the depth of this storm. It has a diameter of 15,400 miles, and its winds have hit 270 mph, at times. In its entirety, it is one sixth of the diameter of the planet Jupiter, making it the largest storm in the solar system. It moves counterclockwise, and its winds could obliterate a town within the space of one minute.

While the spot is very large, it is not always easy to see it. It was first glimpsed by 17th century astronomers, who thought that it was a bruise on the surface of a hard planet, or an explosion in a star. There are certain set days of the year where the Spot is much more visible to the naked eye than others. Consult a sky chart for these dates. The Spot often appears light brown or orange, instead of the red that many people expect. It is best viewed through a blue or light green filter on a lighted telescope.

Many speculations exist about the cause of Jupiter's Spot. These speculations are due to the nature of the planet itself. Jupiter is mainly gas over a solid core of metal. Some even argue that it is a nebula, although this argument is rare. Because of this odd planetary makeup, it is possible that a storm can exist for thousands of years without abating. Most scientists hold that the Spot was caused simply by planetary changes in climate and atmosphere. Others claim that a planet or asteroid crashed into the planet, leaving a swirl of refuse in the area it fell into. According to this theory, a planet the size of Venus hit Jupiter and eventually added its metallic core to Jupiter's solid core mass. The disturbance caused by the collision, however, causes the clouds to swirl to this day. Recent pictures from the Hubble show that the Spot changes color frequently, according to wind changes, temperature changes and atmospheric pressure. It is not known if there are any other causes for this change.

There are many computer technologies that can be used to measure the size movement of Jupiter's Spot. It is an area of great interest to scientists, because they can use the spot to measure temperatures under the core of Jupiter's atmospheres. Because the storm is so rough, scientists can see measure the gases and layers that emerge on the surface, and make calculations about what is below.

Recent evidence points to a spinning motion in the Spot that can be measured from Earth. Scientists have narrowed this time period to a 90-day oscillation pattern, and they are watching the storm accordingly. Careful observation with the naked eye can occasionally spot this effect-the Spot will turn from a clean circle into a more oval shape, then back again. Space probes headed out soon will measure the Spot in detail, giving extensive information about the nature of our planetary system, and Jupiter itself.