科学美国人60秒:Jupiter's Great Red Spot Now Just Pretty Good

Jupiter’s Great Red Spot is looking a little puny lately. The swirling storm has been rapidly shrinking—it’s now smaller than we’ve ever seen it.
 
The spot, once estimated to be 25,500 miles across, was just 10,250 miles wide when the Hubble Space Telescope last observed it. It’s also changing shape, looking more like a circle than its usual oval.
 
Astronomers have been tracking this contraction since at least the 1930s. But lately, the downsizing of the Great Red Spot appears to be speeding up.
 
The massive vortex has been a staple on the solar system’s largest planet ever since it was first recorded in the mid 1800s. Mysteries abound about the spot, such as what powers it and why is it so red. Now add to that, why is it shrinking?
 
One idea is that small eddies feeding into the storm are altering its internal dynamics, sapping its power. Despite its diminishing stature, however, Jupiter’s cyclone is still nothing to laugh at. It continues to reign as the largest known storm in the universe. And it could easily swallow up the entire Earth.

—Clara Moskowitz

(The above text is a transcript of this podcast)