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Weird Orbits of Distant Objects Can Be Explained Without Invoking a 'Planet Nine' (space.com)
schwit1 shares a report from Space.com: The weirdly clustered orbits of some far-flung bodies in our solar system can be explained without invoking a big, undiscovered "Planet Nine," a new study suggests. The shepherding gravitational pull could come from many fellow trans-Neptunian objects (TNOs) rather than a single massive world, according to the research. "If you remove Planet Nine from the model, and instead allow for lots of small objects scattered across a wide area, collective attractions between those objects could just as easily account for the eccentric orbits we see in some TNOs," study lead author Antranik Sefilian, a doctoral student in the Department of Applied Mathematics and Theoretical Physics at Cambridge University in England, said in a statement.
The duo's modeling work suggests that the strength-in-numbers explanation does indeed work -- if the mass of the Kuiper Belt, the ring of bodies beyond Neptune, is a few to 10 times that of Earth. This is a pretty big "if," given that most estimates peg the Kuiper Belt's mass at less than 10 percent that of Earth (and one recent study put the figure at 0.02 Earth masses). But other solar systems are known to harbor massive disks of material in their outer reaches, Sefilian and Touma noted. And our failure to spot one around our own sun doesn't mean it doesn't exist, they stressed. The new study has been accepted for publication in the Astronomical Journal.
The duo's modeling work suggests that the strength-in-numbers explanation does indeed work -- if the mass of the Kuiper Belt, the ring of bodies beyond Neptune, is a few to 10 times that of Earth. This is a pretty big "if," given that most estimates peg the Kuiper Belt's mass at less than 10 percent that of Earth (and one recent study put the figure at 0.02 Earth masses). But other solar systems are known to harbor massive disks of material in their outer reaches, Sefilian and Touma noted. And our failure to spot one around our own sun doesn't mean it doesn't exist, they stressed. The new study has been accepted for publication in the Astronomical Journal.
Of course it can be explained without an planet nine!
I have known this for years! Those weird orbits are due to the gravitational impact of a renowned IT janitor living in San Jose!
Why are you posting some sort of news for nerds and things that matter? This wont generate rage and endless back n forth advertiser views!
We want to know how trump is a Russian spy, a racist, walls are immoral except when around democrat manions, how corruption is bad except when democrats are corrupt, how republicans are evil and steal votes in Chicago, how all republican run places are broken shit holes like San Francisco, Chicago, and Detroit and how cnn and msnbc are news and anyone who reports anything that disagrees is a lying racist transphobe.
Stop posting this science crap. The only science we need is knowing how trump caused global warming to please his master Putin
Comment removed based on user account deletion
^^ Found the whiny denialist republican faggot traitor... well, it found itself and let us all know. For some reason. Put it back in the cage now.
America has never been greater than when it sent so many punk ass faggot right-wing nazi bitches to their early graves. Let's do it again, these traitors belong in Hell. Send Trump and his entire faggot traitor entourage of cowards.
But we already know where Pluto is!
Space Nitschwit
That Planet X, Nibiru, *doesn't* exist? Well where are the lizard people coming from if not there? Check and mate.
The news in 2018 was all "There's a Planet X, there's a Planet X". Fast forward to January 21 2019. Two Cambridge PhD's claim "it may be a ring of smaller" objects. Now the news is all "There is no Planet X, there is not Planet X." Nobody has been able to observe either a 9th Planet or a ring of smaller objects yet. So basically, nobody knows whether there is a 9th Planet out there or not. Everybody's speculating. (Btw, Nibiru sounds like a Linux distro =)
Why did the chicken cross the road? Because Elon Musk put an AI chip in its head.
You've been watching too much fake news on TV. The Nazis were leftists like Democrats.
Fake news also wants you to believe in a magical mystery force called gravity. People with a brain know there's no such force. Space is simply curved, everywhere.
Why do I never see any of you geniuses explaining this to neo-Nazis? I'm sure they'd be most grateful for the heads-up.
FTFA: "January 21, 2019 08:32am ET"
Up your game.
Global Warming: What can't it do!
Wouldn't this just increase the chances of a Kuiper Belt planetoid if the total mass of Kuiper Belt objects was 10x that of Earth?
There is definitely a Planet Nine, and it's called "Pluto."
This is pretty cool.
Once, we thought there was only one planet.
Then we found a few more.
Then we found a whole ring of rocks floating about.
Then we found Pluto.
Then we decided it wasn't really a planet.
Then we learned more about the ring of rocks, their sizes, densities and orbits.
Then we started to map and simulate the orbits of every object in the solar system.
Then we worked out there must be a planet 9.
Then we worked out that it's about 1mm in size, made of super-dense sweat, left over from space giants who had a fight nearby some 100 billion years ago.
Then we worked out we could mine that sweat for super dense fuel
Then we made warp drive
Then we explored the universe and discovered the klingons. Turns out they knew about the space giants all along.
Currently, based on the sizes of the minor planets we have found beyond Neptune, as well as our chance of finding objects, one can extrapolate to a good possibility that we are missing something that is planet sized.
If the mass of the Kuiper belt is far higher than expected, that makes it seem more likely that there is an undiscovered planet out there.
I know this study is specifically about the hypothetical "Planet Nine", used to explain the clustering of some Sednoids. And its alternative explanation for that clustering may be correct. But overall, it seems to suggest that there's a unknown mechanism for adding more mass to the far outer reaches of the solar system.
I will do your bidding.
Lead us, mein Fuhrer
Wouldn't a large number of small object in the Kuiper Belt essentially form a spherical shell with roughly uniformly distributed mass?
http://hyperphysics.phy-astr.g...
Given that, the net gravity and gravitational influence within would be zero so it wouldn't explain anything inside it...
I guess the question is, are the strange orbits inside or outside of the "shell".
Actually...
The news in 2016 was "We can explain the weird orbits of some known Kuiper Belt objects if we assume a planet ten times the size of the Earth."
The news in 2017 was "We can explain the weird orbits of some known Kuiper Belt objects by observation bias; planet nine doesn't need to exist."
The news in 2018 was "There is no planet nine news, but here are a few more Kuiper Belt objects that have the same weird orbits, and planet nine OR observation bias are still in the running."
Now this article comes out and says, "We can also explain the weird orbits of some known Kuiper Belt objects if we assume a large number of objects that have a summed mass of ten times the mass of the Earth."
I have to say, IMNSHO, that this theory doesn't really pass the sniff test. First of all, if the current estimates peg the mass of the Kuiper Belt at 10% the mass of the Earth, what are those estimates based on? Direct visual detection only? Surely those fancy proto-planetary disk simulations that astrophysics grad students run on their VMS Beowulf clusters provide additional insight into the probable mass of the Kuiper Belt. And wouldn't a Kuiper Belt with 10x Earth masses act on the observed planets in a detectable way? Remember that planet nine also helps explain some other, known orbital oddities of the gas giants
Also, when they say that there are other observed systems "that have massive disks of material in their outer reaches" so it's possible we just missed the same thing in our solar system, that seems oversimplified to me. Which specific extra-solar planetary systems have these massive disks of material? Are those systems analogous to our own in age, solar mass, etc.? There are a lot of binary star systems out in the galaxy, too, but that's doesn't mean our system is a binary system, and we just haven't noticed the other star.
Finally, given the way object accrete over time, I would think that 1 large object (or maybe a handful, 2-10) is more likely to exist than thousands or millions of smaller objects of the same total mass. I know that the vast volumes of space in the Kuiper belt slow down such processes, but suggesting the mass of the Kuiper Belt is 3+ orders of magnitude more massive than current models account for is a big ask.
Since people have been looking for planet nine along the projected orbit for several years now without finding either it or any evidence of the massive disk suggested in this article, I'm of the opinion that the whole thing comes down to observation bias. I'll be thrilled if they do find planet nine, but it seems less likely the more the search drags on.