Scientists have uncovered a brand new thriller about Uranus’ rings buried deep in information from NASA’s iconic Voyager 2 mission.
Voyager 2 flew previous Uranus in January 1986, discovering 10 moons and two rings whereas turning into the primary and up to now solely spacecraft to go to the ice giant. A kind of rings, which scientists name the zeta ring, has annoyed astronomers ever since — they weren’t even capable of spot it once more for practically 20 years. However final yr, researchers bought an surprising present: a new image of the Uranus’ ring system, together with the elusive zeta ring, courtesy of novice picture processor Ian Regan.
“For a very long time we thought we solely had two pictures of this ring from Voyager 2,” Matthew Hedman, a planetary scientist on the College of Idaho, mentioned throughout a presentation on the annual assembly of the American Astronomical Society’s Division of Planetary Sciences on Oct. 5. “This exhibits there’s a variety of info nonetheless encoded within the Voyager information that deserves a re-assessment.”
Associated: Uranus by 2049: Here’s why scientists want NASA to send a flagship mission to the strange planet
Scientists initially missed the discover as a result of the reddish dusty ring closest to Uranus wasn’t seen in any particular person picture — Regan needed to mix a bunch of pictures collectively for the function to look. “He took a whole bunch of pictures, stacked them collectively, to provide this picture of the Uranian system,” Hedman mentioned. “That is essentially the most complete view of the zeta ring that exists and we did not comprehend it was within the Voyager information for many years.”
The brand new picture mixed with the earlier two Voyager pictures provided Hedman and his colleagues sufficient info to calculate the ring’s distance from Uranus, about 23,000 miles (37,000 kilometers) above the planet, and to estimate its brightness.
However each of these values are puzzling. The Keck Observatory in Hawai’i had gathered the primary observations of the zeta ring since Voyager 2 in 2007. These observations confirmed the ring at 25,000 miles (40,000 km) above the planet — a bit farther from Uranus than the Voyager 2 observations confirmed.
“The trick is that the situation of this ring did not match the Voyager pictures,” Hedman mentioned of the Keck observations. “One thing had modified about this ring over the course of 20 years. We’re nonetheless not completely positive what that was, although.”
And the zeta ring did not simply inch away from the planet throughout these 20 years it went unmonitored; it additionally registered a stronger sign within the Keck observations than it had in Voyager 2’s view.
“It bought considerably brighter, which implies dust bought launched to the system someday in these 20 years,” Hedman mentioned. “Now, what did that? We don’t know.”
Hedman advised that Uranus might have been hit by a space rock that fragmented into particles and settled within the zeta ring, or that maybe the altering seasons could possibly be accountable, however each are merely concepts. No matter occurred should have been dramatic sufficient to have an effect on the rings, but in addition have slipped beneath scientists’ radar.
NASA will start planning a major mission to explore the Uranus system within the coming years, however scientists will not have information from that mission for a few a long time. Nonetheless, Hedman famous that the James Webb Area Telescope had captured a dazzling image of comparable rings round Neptune, launched in September.
“Happily, there’s a telescope that appears to be superb at taking a look at dusty rings round planets,” he mentioned. “In order that could be good.”
E mail Meghan Bartels at mbartels@space.com or comply with her on Twitter @meghanbartels. Observe us on Twitter @Spacedotcom and on Facebook.
