One of the most distinctive features of the planet Jupiter is the Great Red Spot. The Red Spot is a massive anti-cyclonic storm located in the southern hemisphere of the gas giant. It is easily seen with good binoculars or a telescope. Sadly, the Great Red Spot is becoming less ‘Great’.
Observations from the 1800s record the spot as large as 25,500 miles (41,000 km) across and oval shaped. Voyager 1 and 2 recorded the size of the storm at 14,500 miles (23,000 km) across in 1979. The Hubble Space Telescope photographed the spot at 13,020 miles (21,000 km) across in 1995 and 11,130 miles ( 18,000 km) in 2009. Since 2012, the rate of decrease has noticeably accelerated to 580 miles per year (800 km/yr) and the overall shape is becoming more circular.
Recent Hubble photographs have the storm only 10,250 miles (16,500 km) across. They also show smaller eddy currents around the storm which may be cancelling out the Red Spot’s momentum.
Will the Great Red Spot disappear in our lifetimes? If the rate of shrinkage holds linear, the Spot will be gone in 17 years. Take a look before it is gone.