A Mysterious Ring Surrounding Mini-Planet 'Quaoar' Puzzles Astronomers (space.com) 42
A mini-planet orbiting in the frigid outer reaches of the solar system has a Saturn-like ring of dust and debris that defies the rules of physics, a new study has revealed. Space.com reports: The planet in question is called Quaoar and it's the seventh largest of the known dwarf planets of which Pluto is the king. Discovered in 2002 and about 697 miles wide (1,121 kilometers), Quaoar is one of the so-called trans-Neptunian objects, small planets orbiting beyond the solar system's outermost planet Neptune. Residing in the Kuiper Belt, the doughnut-shaped ring of rocky and icy debris in the outer solar system, Quaoar is a proud owner of its own moon, the 100-mile-wide (160 km) Weywot. And a recent observation campaign revealed that it also has a ring of material in its orbit. [...]
Quaoar's ring is at a very unusual distance from its parent body. In fact, before astronomers discovered Quaoar's ring in observations from several telescopes conducted between 2018 and 2021, they had thought that it was impossible for a ring to exist at such a distance. With a radius of about 2,420 miles (3,885 km) from Quaoar's center, the ring is too far away from the dwarf planet that its gravity should no longer be able to keep the material dispersed. Instead, it should coalesce under its own gravity and form another moon, just like Weywot. By not having done that, the ring has breached what astronomers call the Roche limit, the first known ring around a celestial body to have done so. [...] Now astronomers have to either rethink the Roche limit or come up with another explanation for the existence of Quaoar's ring. The study was published in the journal Nature.
Quaoar's ring is at a very unusual distance from its parent body. In fact, before astronomers discovered Quaoar's ring in observations from several telescopes conducted between 2018 and 2021, they had thought that it was impossible for a ring to exist at such a distance. With a radius of about 2,420 miles (3,885 km) from Quaoar's center, the ring is too far away from the dwarf planet that its gravity should no longer be able to keep the material dispersed. Instead, it should coalesce under its own gravity and form another moon, just like Weywot. By not having done that, the ring has breached what astronomers call the Roche limit, the first known ring around a celestial body to have done so. [...] Now astronomers have to either rethink the Roche limit or come up with another explanation for the existence of Quaoar's ring. The study was published in the journal Nature.
More info (and artist's conception) from space.com (Score:5, Informative)
Re:More info (and artist's conception) from space. (Score:5, Funny)
Thanks for the link! After reading it and looking at the pictures, now I know that it is obviously a Star Gate.
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That was my first thought too (well, except for the fictional elements)
The problem with that idea though is that Quaoar has a moon, which means that we can measure its mass quite accurately (the larger the mass the faster a moon will orbit - the moon's mass has no effect.) So basically we know the planet's mass to withing the accuracy limits of our ability to measure its distance from the moon.
My next off-the-cuff thoughts:
1) the ring is the result of a recent collision and just hasn't yet coalesced.
2) the
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I welcome our symbiotic overlords.
Awesome name. (Score:2)
That whole sector of the solar system is an intriguing mystery. Lots of significant objects we don't understand much.
Re:Awesome name. (Score:4, Informative)
Whoever decided to name something we might some day look at "Quaoar" (kwa-warr) is a media genius.
Wikipedia notes the origin of the name Quaoar [wikipedia.org].
It has a moon named Weywot [wikipedia.org], which means "son of Quaoar."
Name: Upon discovery, Weywot was issued a provisional designation, S/2006 (50000) Brown left the choice of a name up to the Tongva, whose creator-god Quaoar had been named after. The Tongva chose the sky god Weywot, son of Quaoar.
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I suppose so insofar as to spark heated debate on how to pronounce it (the Andorian word is... unpronounceable). Just like quinoa and Gal Gadot, it keeps the story relevant longer.
Pluto (Score:3)
King of the dwarf planets. So still a millimeter too short to ride the roller coaster?
I read TFA fully! (Score:4, Funny)
I read TFA fully!
Here is the resume:
they had thought that it was impossible for a ring to exist at such a distance. With a radius of about 2,420 miles (3,885 km) from Quaoar's center, the ring is too far away from the dwarf planet that its gravity should no longer be able to keep the material dispersed. Instead, it should coalesce under its own gravity and form another moon,
Perhaps (Score:5, Insightful)
Perhaps the ring is a fairly recent phenomenon, and it simply hasn't had time to coalesce into a moon *yet*?
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I've been thinking about that, now the question is, how did it form?
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My knowledge in astrophysics is very spotty, but from what I remember, the problem with this is the distance at which the ring formed. Too close to be explained by an impact, yet too far to remain a ring.
I might talk shit, though, it's been a while.
Second moon (Score:2)
Perhaps Quaoar used to have a second moon, and the ring is what was left in orbit after something hit it.
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The efficiency of impact -to- ring formation is low - typically only a percent or so of the ejecta go to form a ring, with the rest re-accreting, or dispersing.
My question
Re:Perhaps (Score:4, Interesting)
Perhaps the ring is a fairly recent phenomenon, and it simply hasn't had time to coalesce into a moon *yet*?
If I remember correctly, another article I read (can't find it) notes that astronomers estimate that ring *should* coalesce within 20-30 years. Quaoar was discovered in 2002 and the ring in 2018-2021, but they're assuming the ring was around before they observed it.
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Yeah their lack of acknowledgment that these are PROCESSES that take a very, very long time to sort out and that we might just coincidentally 'happen' to see the middle of is ...strange.
TBH it's analogous to the planet-finding community. We tend to look for planets two ways:
- wobble: where we watch the star very carefully to see if it's wobbling (slight blue- and red-ward shifts in the spectrum) which implies a planet in orbit.
- dimming: we watch the brightness of the star to see if it dims on a regular ba
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The eclipse method of detecting exoplanets doesn't depend on the other star system's ecliptic plane being aligned with ours, it merely needs to be edge-on or nearly so (which is bad enough). At the kind of distances we're talking about, the amount of wobble induced by Earth's (or Webb's) orbit around the Sun is tiny even if our ecliptic is 90 degrees from the exoplanet's orbit.
Consider a star 100 lightyears way, which is over six million AU. Over a year, Earth's orbit (offset +/- 1AU) would change our view
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Ummm, bluntly, no. The star's ecliptic plane needs to pass through the surface of the Earth - which at this scale is indistinguishable from the surface of the Sun, or possibly even the surface of Sedna. But it's light does
Scrabble (Score:5, Funny)
Are Kuiper belt objects allowed in Scrabble?
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They are names, so not allowed.
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They are names, so not allowed.
Words With Friends might allow it at some point - they split from Scrabble's word list (and, some might say, from common sense) several years back.
Of course you'd have to wade through all the extraneous crap they added to the app before you could test this, which is not a trivial task (and probably why so many people I know stopped playing).
Massive planet (Score:1)
Maybe it's just very heavy, like filled Plumbum, gold or cheese.
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It is a rather high value for a "small body" - higher even that the much salivated-over Psyche - but not extraordinarily high. It would suggest around 50~60% by volume metals. Suggestive of a violent history, but otherwise not extraordinary.
I'm not saying it's aliens (Score:3)
But, aliens [cactushugs.com].
The Roche limit is static; the universe, dynamic (Score:1)
Maybe it hasn't collapsed yet? Maybe collapse takes a long time? That's the trouble with point measurements: one frame tells you nothing about the rest of the movie.
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Apparently the collapse should take 20-30 years, so if it's the remains of a collision it happened very recently.
Glue (Score:1)
Now astronomers have to either rethink the Roche limit or come up with another explanation for the existence of Quaoar's ring.
- the answer is glue. Everything is stuck together because of sticky glue. The ring, the planet, it is all glued together...
how about a 360 degree panarama (Score:2)
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Umm... there's lots already? Go look at Google maps sky for one of the more detailed and navigable composits: https://www.google.com/sky/ [google.com]
And *every* image of the night sky sees not just to the Oort cloud, but all the way out to the edge of the observable universe. Though it all starts at camera rather than the sun.
The resolution is mostly too low to *see* most of the stuff in the Oort cloud, but that's just the reality of telescopes - the better the magnification, the smaller the piece of sky you can see
A second gig for these astronomers ... (Score:2)
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five bucks (Score:3)
Uranus (Score:2)
I remember on the news when astronomers first discovered rings around Uranus. That was the day they suddenly started pronouncing it Yur-a-nis rather than Yer-anus. It was hilarious!
I assure you...dead man (Score:2)
What was Venus doing at only 40,000 feet?!?
Link to TFP, without "redirecting" service (Score:3)
The authors don't exactly ooze astonishment at their findings, and indeed on the first page of the PDF state "Moreover, Quaoarâ(TM)s ring orbits close to the 1/3 spinâ"orbit resonance with Quaoar, a property shared by Charikloâ(TM)s and Haumeaâ(TM)s rings, suggesting that this resonance plays a key role in ring confinement for small bodies."
But I guess "Scientists find third body with rings outside simple (19th century) non-computational analyses of orbital dynamics" is a less click-generating result than "Scientists astonished ..."
What is a "redirecting" link, and why would anyone want to use one instead of a direct link?