NASA's Webb space telescope has honed its extremely sensitive instruments on the seventh planet from the Sun, Uranus.
Uranus was deemed a top priority for investigation in the 2023-2033 Planetary Science and Astrobiology decadal survey, which aims at finding the most valuable holes in science and filling in those gaps with proposals for knowledge-gaining missions. NASA has now followed up on the requests of the survey by performing some quick observations on Uranus, revealing features of the planet that haven't been seen in a very long time. NASA has taken to its blog to explain the above image of Uranus that was captured with Webb's Near-Infrared Camera (NIRCam) on February 6, 2023.
The image reveals a stunning view of Uranus' rings, with Webb's sensitive instruments managing to capture 11 out of the 13 known rings. Uranus is a unique planet in the solar system as it rotates on a roughly 90-degree angle, which causes the planet to experience extreme seasons as it goes through its long 84-year orbit around the Sun. NASA writes on its blog that because Uranus rotates on its side, one side of the planet's poles goes through years of sunlight while the other side remains in total darkness for an equal number of years.
At the moment, the seventh planet from the Sun is showing its northern pole, which can be seen as the large white smudge consuming the majority of the right side of the planet. Notably, only two other facilities have imaged Uranus, the Voyager 2 spacecraft, which flew past the planet in 1986, and the Keck Observatory. Webb's observations have already led to a greater understanding of the mysterious Uranus as the space telescopes' images have revealed Uranus' polar cap, which appears as a bright white area on the north pole.
"Uranus has 13 known rings and 11 of them are visible in this Webb image. Some of these rings are so bright with Webb that when they are close together, they appear to merge into a larger ring. Nine are classed as the main rings of the planet, and two are the fainter dusty rings (such as the diffuse zeta ring closest to the planet) that weren't discovered until the 1986 flyby by Voyager 2. Scientists expect that future Webb images of Uranus will reveal the two faint outer rings that were discovered with Hubble during the 2007 ring-plane crossing," writes NASA
Currently, researchers don't know much about Uranus' northern polar cap, except that it appears when the pole enters direct sunlight in the summer and that it vanishes in the fall. NASA explains that Uranus' polar cap has never been seen this clearly and can attribute this detail to Webb's infrared capabilities.
Additionally, Webb captured many of Uranus' 27 moons, with six of the brightest moons being identified in the above image. It should be noted that all of these observations were conducted over just 12 minutes and only included two filters. NASA writes that while these observations have changed our understanding of Uranus, they are only just the tip of the scientific iceberg as researchers plan to carry out more that will lead to a greater understanding of the seventh planet from the Sun.
"Webb also captured many of Uranus' 27 known moons (most of which are too small and faint to be seen here); the six brightest are identified in the wide-view image. This was only a short, 12-minute exposure image of Uranus with just two filters. It is just the tip of the iceberg of what Webb can do when observing this mysterious planet," writes NASA