Jupiter and Its Not-So-Great Red Spot

Jupiter's Great Red Spot is a churning anticyclonic storm. It shows up in images of the giant planet as a conspicuous deep red eye embedded in swirling layers of pale yellow, orange and white. Winds inside this Jovian storm rage at immense speeds, reaching several hundreds of kilometers per hour.

Historic observations as far back as the late 1800s gauged this turbulent spot to span about 41 000 kilometers at its widest point – wide enough to fit three Earths comfortably side by side. In 1979 and 1980 the NASA Voyager fly-bys measured the spot at a shrunken 23,335 kilometers across. Now, Hubble has spied this feature to be smaller than ever before.

This full-disc image of Jupiter was taken on 21 April 2014 with Hubble's Wide Field Camera 3 (WFC3).

Image credit: NASA, ESA, and A. Simon (Goddard Space Flight Center)

Note: For more information, see The Shrinking of Jupiter's Great Red Spot, Jupiter's Great Red Spot is Smaller Than Ever Measured, and Jupiter's Great Red Spot is Shrinking.

Jupiter's Great Red Spot

This Voyager 2 image shows the region of Jupiter extending from the equator to the southern polar latitudes in the neighborhood of the Great Red Spot. A white oval, different from the one observed in a similar position at the time of the Voyager 1 encounter, is situated south of the Great Red Spot. The region of white clouds now extends from east of the red spot and around its northern boundary, preventing small cloud vortices from circling the feature. The disturbed region west of the red spot has also changed since the equivalent Voyager 1 image. It shows more small scale structure and cloud vortices being formed out of the wave structures. The picture was taken on July 3, 1979 from 6 million kilometers (3.72 million miles).

Photo credit: NASA/JPL

Jupiter from the Ground

Ground-based astronomers will be playing a vital role in NASA's Juno mission. Because Jupiter has such a dynamic atmosphere, images from the amateur astronomy community are needed to help the JunoCam instrument team predict what features will be visible when the camera's images are taken.

This image was acquired by Damian Peach on September 12, 2010, when Jupiter was close to opposition. South is up and the "Great Red Spot" is visible. Two of Jupiter's moons, Io and Ganymede, can also be seen in this image.

Photo credit: NASA/Damian Peach, Amateur Astronomer

Amateurs to Take a Crack at Juno Images

Data from the camera onboard NASA's Juno mission, called JunoCam, will be made available to the public for processing into their own images. An example of this type of collaboration is illustrated here with an image of Jupiter taken by NASA's Voyager mission, and processed by Björn Jónsson. The image highlights Jupiter's "Great Red Spot."

Photo credit: NASA/JPL-Caltech