While this giant storm is not exactly bearing down on your home town, now is your chance to check it out with a simple tool. The Great Red Spot is a huge anti-cyclonic storm in the southern hemisphere of Jupiter. Normally this huge "spot" can be rather difficult to find because it is embedded in a thick layer of clouds know as the Southern Equatorial Belt. However, since May, this layer of clouds is nearly invisible, for unknown reasons.
What is known, however, is that now is the time to see the Great Red Spot if you can! This time of year, the giant planet Jupiter rises soon after it gets dark and sets after sunrise, allowing stargazers plenty of time to catch a glimpse of it. To the naked eye, the planet will appear as a bright point of light. Grab a pair of 10x50 binoculars and you will see a point of light with up to four tiny specs near it. These are the four main moons of Jupiter, also known as the Galilean moons. In a small telescope, you may see some of the cloud belts in addition to the moons. You may even be lucky enough to see the most well-known feature of Jupiter, the Great Red Spot.
Photo by Anthony Wesley, Murrumbateman, Australia, May 18, 2010.
According to the September issue of Sky and Telescope Magazine, there are several optimal times this month to see the Great Red Spot. While small telescopes may provide a view of it, a telescope larger than six inches is recommended to see more detail, and to make it generally easier to find. The times listed in Sky & Telescope are very specific and coincide with times the Great Red Spot is almost directly facing Earth. Since Jupiter's rotation period is so short (less than twelve hours), the Great Red Spot faces Earth a couple of times per day, although it may not be when your side of the planet is in darkness.
Some of the best times for seeing the Great Red Spot in the U.S. over the next few days are as follows (From the September 2010 issue of Sky & Telescope):
-September 9th: 8:30pm EDT (00:30 UTC)
-September 10th: 6:26am EDT (10:26 UTC)
-September 11th: 2:17am EDT (6:17 UTC)
-September 11th: 10:08pm EDT (2:08 UTC)
-September 13th: 3:55am EDT (7:55 UTC)
-September 13th: 11:46pm EDT (3:46 UTC)
-September 15th: 5:33am EDT (9:33 UTC)
Bron: Accuweather