NASA’s James Webb Space Telescope has captured a gorgeous wide-field image of Uranus. Using its near-infrared camera (NIRCam), the most powerful observatory ever launched into orbit detailed the planet’s seasonal north polar cap, inner and outer rings, and even some of Uranus’ moons.
This week’s image is even more detailed than the one Webb snapped in April. At the time, that image was the best view of Uranus we’d seen since NASA’s Voyager 2 swung by in the mid-1980s. While the difference in definition between Voyager 2’s glimpse and Webb’s April image was astronomical, this week’s depiction of Uranus isn’t so starkly different from the last. Still, it allows us to see a number of exciting features.
The most timely of these is Uranus’ seasonal north polar cloud cap, which is more visible in the above image than ever before. As the planet’s pole shifts toward the Sun, this polar cap receives extra light and becomes more pronounced. NASA also points out that a slew of bright storms hover near and below the polar cap’s southern border, prompting questions about the ways in which these storms—and the polar cap itself—might fluctuate as Uranus approaches solstice. The ice giant will reach solstice in 2028, leaving astronomers with plenty of time to monitor related seasonal and meteorological phenomena.
Credit: NASA, ESA, CSA, STScI
Another impressive difference between this week’s image and the one shared in April involves many of Uranus’ moons. While the image from earlier this year wasn’t quite sharp enough to include any of the ice giant’s 27 moons, this new perspective allows us to see Belinda, Bianca, Cressida, Desdemona, Juliet, Perdita, Portia, Puck, and Rosalind—small, dim moons that orbit closer to Uranus itself, making them historically difficult to see. Webb’s image also includes Ariel, Miranda, Titania, and Umbriel, which are four of Uranus’ biggest and brightest moons.
One of the planet’s most distinctive features, however, is its collection of icy rings. We got a pretty good look at these back in April, but now we can see Zeta, Uranus’ faint and diffuse innermost ring. Uranus’ outer rings are vibrant, too, offering us what NASA calls an “exquisite” view of the ice giant’s iconic silhouette.
More than just a pretty picture, Webb’s work will help NASA prepare for future Uranus missions with its unprecedented detail. The agency also says Uranus can serve as a proxy for nearly 2,000 exoplanets by offering insight into planet formation and meteorology.
