Jupiter Breaks Out in Spots

A third red spot has appeared on Jupiter in what astronomers called a case of the planetary measles.

Astronomers spotted the new storm — a distant smaller cousin of the Great Red Spot and Little Red Spot — using the Hubble Space Telescope and W.M. Keck telescope to get both visible-light and near-infrared images.

Turbulent storms are common in Jupiter?s atmosphere, although the red color in the biggest storms remains a mystery. The new red spot, announced yesterday, was previously a white, oval-shaped storm.

One theory suggests such storms have enough power and size to dredge material from deep beneath Jupiter?s clouds and lift it to higher altitudes, exposing it to solar ultraviolet radiation that changes the color to the now-familiar red.

Early telescope observations indicate that the Great Red Spot has lasted somewhere between 200 and 350 years, while the Little Red Spot appeared in spring 2006. The third red spot was spotted in Hubble and Keck images taken between May 9 and May 11 of this year.

The newest storm may end up merging with the Great Red Spot when the two meet in August, assuming they continue on their current paths, astronomers said. Otherwise the Great Red Spot may simply shove its smaller cousin aside.

The latest Hubble and Keck images also support the idea of Jupiter undergoing global climate change. Warming near the giant planet?s equator and cooling at the South Pole could be destabilizing the southern hemisphere, causing jet streams to go haywire and spawn new storms.

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