SETH BORENSTEIN
AP Science Writer

WASHINGTON (AP) — Jupiter’s Great Red Spot seems to be on a cosmic diet, shrinking rapidly before our eyes.

Astronomers using the Hubble Space Telescope calculate that the spot, a giant long-lasting storm, is narrowing by about 580 miles a year, much faster than before.

In the late 1800s the red spot was an oval 25,500 miles wide. Now it’s a circle that’s 10,250 miles across.

Michael Wong, a scientist at the University of California, Berkeley, said the spot is a mystery. Astronomers don’t know why it’s red or shrinking, or what will happen next. If this pace continues, in 17 years the spot could be gone. Or it could stop at a smaller size.

Wong said one theory is the spot eats smaller storms, and that it is consuming fewer of them.

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