The biggest storm on the biggest planet in the solar system is losing its punch.
New pictures from the Hubble Space Telescope show Jupiter's so-called Great Red Spot is the smallest it has been since observations began more than 100 years ago.
ANALYSIS: Go to Jupiter for the Best French Fries
The spot, which appears as a deep red oval surrounded by swirling layers of yellow, orange and white, actually is a raging storm - the largest in the solar system - with winds blasting at hundreds of thousands of miles per hour.
Scientists have known for some time that the spot is shrinking. When it was first detected in the late 1800s, it appeared to be about 25,000 miles across, which is more than the diameter of three Earths.
When NASA's twin Voyager spacecraft passed by Jupiter in 1979 and 1980, the red spot had trimmed down to about 14,500 miles in diameter.
NEWS: Why Jupiter's Red Spot Won't Die
Images taken by the Hubble Space Telescope and released on Thursday now show the spot is down to less than 10,250 miles at its widest point.
Scientists suspect the change has something to do with eddies that are feeding the storm and zapping it of energy.
"It is apparent that very small eddies are feeding into the storm ... These may be responsible for the accelerated change by altering the (storm's) internal dynamics," astronomer Amy Simon, with NASA's Goddard Space Flight Center in Greenbelt, Md., said in a statement.
So is the Great Red Spot doomed?
"That is a tough question because, of course, we don't know," Simon wrote in an email to Discovery News.
NEWS: Jupiter Is Undergoing Massive, Global Changes
"Atmospheric storms are not usually stable over very long time periods. On Earth they dissipate relatively quickly, as they do on all terrestrial planets. (Land really helps to break up storms.)
"This one is high pressure, and generally more stable than say, a hurricane, but even our best atmospheric models have a difficult time reproducing a very long-lived vortex on a gas giant planet. In other words, there is every reason why the Great Red Spot should have disappeared long ago, so it is somewhat more surprising that it hasn't," she said.
"Whether the current change in size means it is suddenly on track to go away, we'll just have to wait and see."