In what's beginning to look like a case of planetary measles, a third red spot has appeared alongside its cousins — the Great
Red Spot and Red Spot Jr. — in the turbulent Jovian atmosphere.

This third red spot, which is a fraction of the size of the two other features, lies to the west of the Great Red Spot in the same
latitude band of clouds.

The new red spot was previously a white oval-shaped storm. The change to a red color indicates its swirling storm clouds are
rising to heights like the clouds of the Great Red Spot. One possible explanation is that the red storm is so powerful it dredges
material from deep beneath Jupiter's cloud tops and lifts it to higher altitudes where solar ultraviolet radiation — via some
unknown chemical reaction — produces the familiar brick color.

Detailed analysis of the visible-light images taken by Hubble's Wide Field Planetary Camera 2 on May 9 and 10, and near-
infrared adaptive optics images taken by the W.M. Keck telescope on May 11, is revealing the relative altitudes of the cloud
tops of the three red ovals. Because all three oval storms are bright in near-infrared light, they must be towering above the
methane in Jupiter's atmosphere, which absorbs the Sun's infrared light and so looks dark in infrared images.

Turbulence and storms first observed on Jupiter more than two years ago are still raging, as revealed in the latest pictures. The
Hubble and Keck images also reveal the change from a rather bland, quiescent band surrounding the Great Red Spot just over
a year ago to one of incredible turbulence on both sides of the spot.

Red Spot Jr. appeared in spring of 2006. The Great Red Spot has persisted for as long as 200 to 350 years, based on early
telescopic observations. If the new red spot and the Great Red Spot continue on their courses, they will encounter each other
in August, and the small oval will either be absorbed or repelled from the Great Red Spot. Red Spot Jr. which lies between the
two other spots, and is at a lower latitude, will pass the Great Red Spot in June.

The Hubble and Keck images may support the idea that Jupiter is in the midst of global climate change, as first proposed in
2004 by Phil Marcus, a professor of mechanical engineering at the University of California, Berkeley. The planet's temperatures
may be changing by 15 to 20 degrees Fahrenheit. The giant planet is getting warmer near the equator and cooler near the South
Pole. He predicted that large changes would start in the southern hemisphere around 2006, causing the jet streams to become
unstable and spawn new vortices.

The Hubble team members are Imke de Pater, Phil Marcus, Mike Wong and Xylar Asay-Davis of the University of California,
Berkeley, and Christopher Go of the Philippines. The Keck team members were de Pater, Wong, and Conor Laver of the
University of California, Berkeley, and Al Conrad of the Keck Observatory. More information about the Keck observations is
available in The University of California, Berkeley press release (http://www.berkeley.edu/news/media/releases/
2008/05/22_redspots.shtml). The contributions by the amateur network (http://jupos.privat.t-online.de/) are invaluable for this
research.

For additional information, contact:

Ray Villard
Space Telescope Science Institute, Baltimore, Md.
410-338-4514
villard@stsci.edu