Plunge Into Jupiter’s Great Red Spot In New Video

Using imagery from NASA’s Juno spacecraft, animators created this visualization of a flight into Jupiter’s Great Red Spot. The video begins about 2,000 miles (3,000 km) above the cloud tops of the planet’s southern hemisphere.

Every school kid knows Jupiter has a big red spot. Called the Great Red Spot, it’s a titanic oval storm 1.3 times the size of the Earth and big enough to see in a 6-inch telescope. Data collected by NASA’s Juno spacecraft during its first pass over Jupiter’s Great Red Spot in July 2017 indicate that this iconic feature penetrates well below the clouds.

“One of the most basic questions about Jupiter’s Great Red Spot is: how deep are the roots?” said Scott Bolton, Juno’s principal investigator, in a press release. “Juno data indicate that the solar system’s most famous storm has roots that penetrate about 200 miles (300 km) into the planet’s atmosphere.”

Regular cameras and telescopes can’t peer through clouds, but microwaves can. They’re also pretty good at heating a cup of tea. Juno carries something called a microwave radiometer that can detect what’s going on hundreds of miles below Jupiter’s cloud tops.  With it, scientists are finally getting to the bottom of the Great Red Spot.

NASA’s Juno spacecraft took this photo of Jupiter’s Great Red Spot on July 10 from a distance of just 5,600 miles (9,000 km). Clouds spin counterclockwise within the oval. Juno senses microwaves from deep below the Spot that reveal what the clouds are made of and their temperatures.  NASA/JPL-Caltech

“Juno found that the Great Red Spot’s roots go 50 to 100 times deeper than Earth’s oceans and are warmer at the base than they are at the top,” said Andy Ingersoll, professor of planetary science at Caltech and a Juno co-investigator.

The difference in temperature between the hot bottom and cold top drives powerful winds that whirl clouds around the Spot’s outer edge at between 270 and 425 miles per hour (430-680 kph). Way stronger than a Category 5 hurricane. But like a hurricane the center of the GRS is relatively calm.

The future of the Great Red Spot is still up for debate. While the storm has been known for more than 300 years and monitored closely since 1830, it’s been shrinking of late. In the 19th century, the Great Red Spot was well over two Earths wide. Even at the time NASA’s Voyagers 1 and 2 sped by Jupiter on their way to Saturn and beyond, in 1979, the Great Red Spot was twice Earth’s diameter. Today, measurements by Earth-based telescopes indicate the oval that Juno flew over has diminished in width by one-third and height by one-eighth since Voyager times.

The Great Red Spot has been shrinking over the past few decades. The photo at upper right was taken by the Hubble Space Telescope in 1995 and shows the spot just under 13,050 miles (21,000 km) across; the second down is from 2009 with the spot at just under 11,180 miles (18,000 km); and the bottom photo is from 2014, when it was just 9,940 miles (16,000 km) wide. NASA/ESA


To date, Juno has completed eight science passes over Jupiter. Juno’s ninth science pass will be on Dec. 16.

2 Responses

  1. Edward M. Boll

    I have been noting Mars lately since it is now over 20 degrees high in a dark sky. The Geminids were completely clouded out here. Too bad since the mornings are warm for December.The last clear skies were late on the 12th.

    1. astrobob

      Hi Edward,

      Sorry to hear about the weather. Mars is doing great, isn’t it? Slowly getting out of bed and getting ready for a great apparition next year. We got very lucky with a clear sky from 9 till midnight, so the Geminids were excellent here in Duluth.

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