New images taken by the Hubble Space Telescope of gas giant planets Jupiter and Uranus have been published that show intriguing interplanetary weather conditions.
Taken by Hubble’s Wide Field Camera 3 as part of the annual Outer Planet Atmospheres Legacy (OPAL) program, the new images of Jupiter taken in November 2022 and January 2023 show the planet’s famous “Great Red Spot,” an anticyclonic storm roughly the diameter of Earth. However, they also show a wave of cyclones and anticyclones moving clockwise and counterclockwise, all of which have appeared in the last 10 years.
In the image above (this article’s main image) it’s possible to see Jupiter’s orangey moon Io—the most volcanic body in the entire solar system—as it transits the giant planet to cast a dark shadow up its colorful cloud tops. It’s visible below, too, in the left-hand image.
On the right of this image (above) you can see the Great Red Spot. A 400-years old storm that used to be twice the size of Earth, but has since shrunk slightly, it’s rolling counterclockwise between two bands of clouds that are moving in opposite directions toward it. Inside winds blow at 425 miles per hour.
On the right-hand image you can see Jupiter’s icy moon Ganymede transiting the giant planet. It’s the largest moon in the solar system—even bigger than planet Mercury and dwarf planet Pluto—and is the only moon known to have a magnetic field.
Next month Europe’s JUICE spacecraft (Jupiter Icy Moons Explorer) will launch to eventually orbit Ganymede, though the journey will take eight years.
Close to the Great Red Spot is the Great Red Worm—to the top-right of the massive storm in this image— a reddish sausage-shaped vortex spinning in the opposite direction. The white white ovals beneath and behind Ganymede are anticyclones—smaller versions of the Great Red Spot.
Meanwhile, Uranus—also captured by Hubble—displays a growing polar cap of high-altitude haze. It looks rather like smog over a city. You can see it growing in these two photos, above, from November 2014 and November 2022, respectively.
Uranus takes 84 years to orbit the Sun, but rotates on its side, so for up to half a year (equal to 42 Earth-years) large parts of one hemisphere are completely hidden from sunlight. These images from Hubble show Uranus’ north pole tipping towards the Sun, while NASA’s Voyager 2 probe—which conducted a flyby in the 1980s—imaged its south pole.
As well as Jupiter and Uranus, the annual OPAL project studies the atmospheric dynamics and evolution of Saturn and Neptune. It uses Hubble’s 16 megapixel Wide Field Camera 3 (WFC3) to create the 360° mosaics of planets you see here.