Register for an account

X

Enter your name and email address below.

Your email address is used to log in and will not be shared or sold. Read our privacy policy.

X

Website access code

Enter your access code into the form field below.

If you are a Zinio, Nook, Kindle, Apple, or Google Play subscriber, you can enter your website access code to gain subscriber access. Your website access code is located in the upper right corner of the Table of Contents page of your digital edition.

The Sciences

The G-R Spot

Newsletter

Sign up for our email newsletter for the latest science news

Jupiter's Great Red Spot has intrigued observers ever since French astronomer Gian Domenico Cassini first sighted it in 1665. The Galileo spacecraft, orbiting Jupiter, took these images at four different infrared wavelengths in September 1996; astronomers analyzed them last spring for the first time. The top image shows light reflecting off clouds high in Jupiter's atmosphere. The next image shows haze in the stratosphere over the Great Red Spot (at the lower left corner) and the North Equatorial Belt. The third shows clouds about 50 miles down into Jupiter's atmosphere. Heat emissions from still deeper in the atmosphere are visible between clouds in the bottom image. The spot resembles a huge terrestrial hurricane, says Fred Taylor, an atmospheric physicist at Oxford who studied the images. Damp air, probably containing water and ammonia, spouts upward from far below the center of the storm, spraying out over the top in a mushroom shape as it condenses into the spot's distinctive red clouds. But why is the Great Red Spot red? "It's difficult to make red clouds; it's an uncommon thing in atmospheres," says Taylor, who hopes two more years' worth of data will solve the riddle. "But it may be that what we need is another probe actually dropping into the Red Spot to make the right kinds of measurements to answer that question."

    2 Free Articles Left

    Want it all? Get unlimited access when you subscribe.

    Subscribe

    Already a subscriber? Register or Log In

    Want unlimited access?

    Subscribe today and save 70%

    Subscribe

    Already a subscriber? Register or Log In