Astronomers find ring around distant dwarf planet Quaoar
The uncertainty of science: Astronomers have confirmed the existence of an uneven ring encircling the dwarf planet Quaoar, orbiting far enough from the planet that, according to present theories, the ring should have quickly coalesced into a small Moon.
At 1,110 km (690 miles) in diameter Quaoar is one of the largest objects known in the outer solar system. Its single moon, named Weywot, spans about 160 km and was discovered in Hubble images in 2007. But the first signs of material around Quaoar didn’t come until 2018; even then, evidence was insufficient to call it a ring, says Morgado. He began studying Quaoar in 2020 with the European Space Agency’s CHEOPS space telescope, originally designed to find and characterize exoplanets. Rather than looking for exoplanet transits, Morgado used CHEOPS to observe stellar occultations, when Quaoar passed in front of distant stars and momentarily blocked their light.
Now Morgado has extended his work, working with others to observe Quaoar’s stellar occultations using other telescopes. The team first predicted a few occultations and recorded them. Then, after those observations hinted at a ring, the researchers went back through previous occultation records. “We saw the ring in nine different regions, from observations taken between 2018 and 2021,” Morgado explains.
In Nature, the team reports the presence of a ring 4,100 kilometers from the center of Quaoar, far beyond its classical Roche limit of 1,780 km. Morgado says the ring is dense and irregular. “It has a very thin region about 5 km wide and also a large region about 300 km wide, depending on which part of the ring was probed,” he notes. If the material could all be collected into a single moon, it would be about 10 km in diameter, less than a tenth of Weywot’s size.
According to astronomers, they would expect such a ring at that distance to coalesce in just a matter of decades. Either their theories of the Roche limit are incorrect, or the creation of this ring is very very recent, caused by the collusion of two objects that were orbiting Quaoar.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The uncertainty of science: Astronomers have confirmed the existence of an uneven ring encircling the dwarf planet Quaoar, orbiting far enough from the planet that, according to present theories, the ring should have quickly coalesced into a small Moon.
At 1,110 km (690 miles) in diameter Quaoar is one of the largest objects known in the outer solar system. Its single moon, named Weywot, spans about 160 km and was discovered in Hubble images in 2007. But the first signs of material around Quaoar didn’t come until 2018; even then, evidence was insufficient to call it a ring, says Morgado. He began studying Quaoar in 2020 with the European Space Agency’s CHEOPS space telescope, originally designed to find and characterize exoplanets. Rather than looking for exoplanet transits, Morgado used CHEOPS to observe stellar occultations, when Quaoar passed in front of distant stars and momentarily blocked their light.
Now Morgado has extended his work, working with others to observe Quaoar’s stellar occultations using other telescopes. The team first predicted a few occultations and recorded them. Then, after those observations hinted at a ring, the researchers went back through previous occultation records. “We saw the ring in nine different regions, from observations taken between 2018 and 2021,” Morgado explains.
In Nature, the team reports the presence of a ring 4,100 kilometers from the center of Quaoar, far beyond its classical Roche limit of 1,780 km. Morgado says the ring is dense and irregular. “It has a very thin region about 5 km wide and also a large region about 300 km wide, depending on which part of the ring was probed,” he notes. If the material could all be collected into a single moon, it would be about 10 km in diameter, less than a tenth of Weywot’s size.
According to astronomers, they would expect such a ring at that distance to coalesce in just a matter of decades. Either their theories of the Roche limit are incorrect, or the creation of this ring is very very recent, caused by the collusion of two objects that were orbiting Quaoar.
On Christmas Eve 1968 three Americans became the first humans to visit another world. What they did to celebrate was unexpected and profound, and will be remembered throughout all human history. Genesis: the Story of Apollo 8, Robert Zimmerman's classic history of humanity's first journey to another world, tells that story, and it is now available as both an ebook and an audiobook, both with a foreword by Valerie Anders and a new introduction by Robert Zimmerman.
The print edition can be purchased at Amazon or from any other book seller. If you want an autographed copy the price is $60 for the hardback and $45 for the paperback, plus $8 shipping for each. Go here for purchasing details. The ebook is available everywhere for $5.99 (before discount) at amazon, or direct from my ebook publisher, ebookit. If you buy it from ebookit you don't support the big tech companies and the author gets a bigger cut much sooner.
The audiobook is also available at all these vendors, and is also free with a 30-day trial membership to Audible.
"Not simply about one mission, [Genesis] is also the history of America's quest for the moon... Zimmerman has done a masterful job of tying disparate events together into a solid account of one of America's greatest human triumphs."--San Antonio Express-News
The Mi-Go Starlink.
They found a ring around Uranus to a vertical ring
Jeff Wright: Your attempt to post another two comments with millions of links failed because my system rejected all three. It is very possible there was some obscene letter combinations in the urls, unintended, that sent all three to moderation.
No matter. In the future, if you want to post some links like this, limit the number in each comment to less than ten. It also might make it more likely people will actually check them out. As you have been doing it, it really has been just one step above spam.
And don’t post ten comments with ten links. That won’t work either.
The ring around Uranus is nearly vertical because the planet’s axis tilt is some 98 degrees.