"Aernus", A proposed new planet in the Kuiper Belt |
"Aernus", A proposed new planet in the Kuiper Belt |
Oct 11 2007, 08:40 AM
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Special Cookie Group: Members Posts: 2168 Joined: 6-April 05 From: Sintra | Portugal Member No.: 228 |
Tomorrow at DPS Patryk Lykawka will make a presentation where he points out to the existence of a planet with the diameter of the Earth at 100AU.
I received his answers regarding the work done yesterday, here's some of it (the rest is you know where...): "This massive planetesimal would be, now, at this moment in the history of the Solar System, orbiting the Sun at a distance of, at least, 100 AU, or, simplifying, 3 to 4 times more distant from our star than Pluto. A far, massive, transplutonian planet in the Lykawka’s description who remarks the importance that the orbital evolution of this planet may be the key to answer several unexplained enigmas of the Kuiper Belt, among which he points out a few…: The excitation actually observed in the region between 40 and 50 AU is one, another are the populations of different types of objects in the Belt and their orbital characteristics. Another two pieces of the puzzle can also be put into place under Patrik work: the Belt’s truncated region in the 48 AU region and its small total mass." What's your opinion regarding this?... According to him this is not like Planet X, his study even erases Planet X from the map... EDITED: "Aernus" is the name I'm using, it was the divinity of the Zoelae, a pre-historic tribe that lived in the most remote corner of my country... -------------------- "Ride, boldly ride," The shade replied, "If you seek for Eldorado!"
Edgar Alan Poe |
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Jun 18 2008, 07:12 PM
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
MSNBC is running a story on this today:
http://harbor.scitec.kobe-u.ac.jp/~patryk/...a-Planetoid.pdf Apparently Patryk has a new paper in the Astrophysical Journal today, although I can't find a link to it on his site: http://harbor.scitec.kobe-u.ac.jp/~patryk/index-en.html My biggest question, though, is why he thinks it would only be a "plutoid," since he seems to be describing a very large (Earth-diameter, but 1/3 mass) object well outside the Kuiper Belt -- something that almost certainly would have cleared its orbit. --Greg |
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Jun 18 2008, 11:03 PM
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Member Group: Members Posts: 529 Joined: 19-February 05 Member No.: 173 |
MSNBC is running a story on this today: http://harbor.scitec.kobe-u.ac.jp/~patryk/...a-Planetoid.pdf Apparently Patryk has a new paper in the Astrophysical Journal today, although I can't find a link to it on his site: http://harbor.scitec.kobe-u.ac.jp/~patryk/index-en.html My biggest question, though, is why he thinks it would only be a "plutoid," since he seems to be describing a very large (Earth-diameter, but 1/3 mass) object well outside the Kuiper Belt -- something that almost certainly would have cleared its orbit. --Greg At Pluto's orbit, Earth would not be a planet by IAU standards. Silly, I know. At 100 AU, a several Earth mass object would be disqualified. This is a consequence of the zone clearing criteria which biases what is and is not a planet by distance-- so that objects that are planets at 1 AU like Earth are not planets at 30 AU. You know what I think of this. Now for a prediction: It shall fall before NH reaches Pluto. Too many people are figuring it out. Google "Great Planet Debate." -Alan |
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Jun 19 2008, 01:48 AM
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
At 100 AU, a several Earth mass object would be disqualified. This is a consequence of the zone clearing criteria which biases what is and is not a planet by distance But the Kuiper Belt ends at 55 AU, right? Why wouldn't an Earth-sized object at 100 AU be a planet, provided it orbited in splendid isolation? Now for a prediction: It shall fall before NH reaches Pluto. I wouldn't be surprised if results from Pan-STARRS and/or LSST will force a radical rethink, and I note first light for LSST is scheduled for about the same time as N reaches Pluto. But the real reason I posted here was to see a) if anyone has a link to the actual paper and how serious one ought to take it. --Greg |
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Jun 19 2008, 04:27 AM
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Senior Member Group: Members Posts: 2530 Joined: 20-April 05 Member No.: 321 |
But the Kuiper Belt ends at 55 AU, right? Why wouldn't an Earth-sized object at 100 AU be a planet, provided it orbited in splendid isolation? I guess the thought would be that that can't happen. For an Earth-sized object to be at 100 AU, the stuff for it to accrete out of has to be out there at about 100 AU. It couldn't have formed somewhere else and then made its way out there and just stopped unless there were something bigger out there. (A highly felicitous impact that significantly changed its orbit could do so, providing it didn't blast enough stuff off to once again reject the axiom.) The period of an object at 100 AU is 1000 years. The volume of space around its orbit proportional to that of Earth is a million times as great. I'm certain the Earth hadn't cleared its orbit in 4.5 million years (the impacts on the Moon make that clear -- not by a long shot). So there's no reason to suspect that the "Early Heavy Bombardment" would even be over at that distance. Unless there wasn't enough stuff there for an Earth-sized object to accrete. |
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Jun 19 2008, 02:55 PM
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Senior Member Group: Members Posts: 1018 Joined: 29-November 05 From: Seattle, WA, USA Member No.: 590 |
I guess the thought would be that that can't happen. If that's the case, that's fine; I'm surprised we'd be that confident, though. Seems to depend a lot on assumptions about the original mass of the disk out there, plus the original composition. We can't already know everything or we wouldn't need to send NH out there! ;-) Getting back to the paper (or the news article about the paper), it appears he's claiming this object is large enough to establish the outer edge of the Kuiper Belt -- just as Jupiter establishes (I think) the outer edge of the Asteroid Belt. Unless you take a rather disingenuous interpretation of "clearing the orbit" ("I want this orbit clean enough to EAT off of!") :-) then I'd say that anything that can limit the Kuiper Belt has really gone above and beyond the call of duty as far as orbit-cleaning goes. Which gets back to my original question (which wasn't aimed at continuing the "is it a planet discussion"): Is Lykawka's hypothesis reasonable? --Greg |
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