The Great Red Spot on Jupiter might one day be the Average Red Spot; NASA says it's shrinking at a rate of 580 miles a year, the distance between Chicago and Washington, D.C.
For at least 400 years, NPR says, the anticyclonic vortex has been churning in the atmosphere of the planet, a gigantic storm that is big enough to engulf three Earths. As it gets smaller, the shape begins to shift as well, and by 2040 it could become circular. In 1979, the Great Red Spot was 14,500 miles across, in 1995 it was 13,020 miles across, and by 2009 it was down to 11,130 miles across. Now, it's 10,250 miles along the east-west axis.
NASA hypothesizes that the Great Red Spot is shrinking because "very small eddies are feeding into the storm." Amy Simon of NASA's Goddard Space Flight Center adds that the eddies are possibly "altering the internal dynamics and energy of the Great Red Spot." Simon and the rest of her team will study the eddies and the storm's internal dynamics to get to the bottom of "this yet unexplained shrinkage."