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Caltech Astronomers Say a Ninth Planet Lurks Beyond Pluto ( 258

sciencehabit writes: The solar system may have a new ninth planet. Today, two scientists announced evidence that a body nearly the size of Neptune — but as yet unseen — orbits the sun every 15,000 years. During the solar system's infancy 4.5 billion years ago, they say, the giant planet was knocked out of the planet-forming region near the sun. Slowed down by gas, the planet settled into a distant elliptical orbit, where it still lurks today. Here's a link to the full academic paper published in The Astronomical Journal.
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Caltech Astronomers Say a Ninth Planet Lurks Beyond Pluto

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  • With a 15,000 earth-year long orbit of the sun, it could be a while before this is anything more than an inference.

  • by Rob MacDonald ( 3394145 ) on Wednesday January 20, 2016 @12:58PM (#51336965)
    To tell us how this planet oscillates the chemtrails so the 911 nuclear aliens can open up communications with the illuminati and space lizards to bring on the new world order and force us into fema camps.
  • by Anonymous Coward

    ...and here comes Nibiru []?

    Hint: +1 Funny

  • Lets name this planet Pluto and really piss off Neil deGrasse Glactus.
    • There is already a planet with that name.... so, in true gamer fashion, we will not let that deter us.

      We shall call it: xXPlutoXx

  • by voislav98 ( 1004117 ) on Wednesday January 20, 2016 @01:09PM (#51337091)
    Step 1: Rename Pluto
    Step 2: Name the new planet Pluto
    Step 3: Profit!
  • Unless I read it on Forbes, I ain't believing it.
  • Dear Ethan (Score:5, Insightful)

    by Anonymous Coward on Wednesday January 20, 2016 @01:12PM (#51337123)

    Please read TFA and consider it a good example of how to write something informative, accessible and entertaining, but most importantly not hosted on forbes.

  • I KNEW IT! (Score:5, Funny)

    by Anonymous Coward on Wednesday January 20, 2016 @01:19PM (#51337203)

    This finally explains all the times my horoscope wasn't entirely accurate. With this new input, I'm sure that I will be able to use my horoscope to see what the stars have for me and I will be able to intelligently make life-decisions knowing how they are arranged.

    N.B. - I started the above in jest, but let's observe a moment of silence for the poor folks who actually feel that way.

    • When the Moon is in the second house, and Neptune aligns with Uranus...
  • by necro81 ( 917438 ) on Wednesday January 20, 2016 @01:21PM (#51337227) Journal
    A computer model that predicts the existence of a ninth planet (of substantial mass, ejected into a distant orbit, early in the solar system) does not, by the usual scientific method, constitute evidence. Evidence of its existence would be certain observables that others could also observe and verify: perturbations in the orbits of other planets, detection in a telescope, etc.

    This is a prediction by a hypothesis - nothing more. I could create a model that predicts the existence of dragons that fart nerve gas - that does not count as "evidence of an impending apocalypse," although that would surely generate many clicks.
    • by asylumx ( 881307 )
      Evidence, yes. Proof, no.
    • by mothlos ( 832302 ) on Wednesday January 20, 2016 @01:35PM (#51337367)

      It is a hypothesis which is supported by evidence. The existence of Jupiter is also a hypothesis which is supported by evidence, although much stronger evidence than the evidence for this planet. Epistemology is frequently at odds with our every day feelings about knowledge.

    • by avgjoe62 ( 558860 ) on Wednesday January 20, 2016 @01:37PM (#51337393)

      You really need to read the articles. To quote from one of them:

      But the real kicker for the researchers was the fact that their simulations also predicted that there would be objects in the Kuiper Belt on orbits inclined perpendicularly to the plane of the planets. Batygin kept finding evidence for these in his simulations and took them to Brown. "Suddenly I realized there are objects like that," recalls Brown. In the last three years, observers have identified four objects tracing orbits roughly along one perpendicular line from Neptune and one object along another. "We plotted up the positions of those objects and their orbits, and they matched the simulations exactly," says Brown. "When we found that, my jaw sort of hit the floor."

      "When the simulation aligned the distant Kuiper Belt objects and created objects like Sedna, we thought this is kind of awesome—you kill two birds with one stone," says Batygin. "But with the existence of the planet also explaining these perpendicular orbits, not only do you kill two birds, you also take down a bird that you didn't realize was sitting in a nearby tree."

    • by Anonymous Coward

      Perturbations of other (dwarf) planets and KBOs is exactly what they are basing this claim off of.

      That data strongly supports a massive body well outside Neptune's orbit, but until now no one could say if it was a large planet farther out, or an Earth-sized planet closer in (relatively). Some people even suggested it could be a brown dwarf binary very far out.

      These guys have now used the preexisting data to predict that it's a smaller planet "close" in based on computer modeling.

    • Go to the military with the fart nerve gas idea. They'll fund lifelong research if you promise them all jobs when they retire. And, yes. A computer model is not evidence in any way.If it can predict the location and then the planet is discovered, we'll all be impressed. Not until then.
    • by pz ( 113803 ) on Wednesday January 20, 2016 @01:53PM (#51337543) Journal

      If you read the article (I know, I know), you'll learn that there are, in fact, observables involved. There are a handful of Kuiper Belt objects that have an odd level of similarity among them, so odd that the only ready explanation is that there is an as-yet unseen object shepherding them. The Caltech group created a simulation of the kind of object that might produce such a result and found that it ALSO would be expected to shepherd a second set of smaller objects into orbits orthogonal to the ecliptic. Very, very strange. So they made that prediction, and LO! found objects that fit the bill.

      They created a theory based on observational evidence. The theory made a prediction that was tested, and found correct. The body itself has not been observed, yet, but I'd expect that the Japanese will find it (given that, according to other news articles), they have just the right sort of telescope to perform the search.

    • by tyme ( 6621 )

      The evidence is the observed orbital properties of distant Kuiper belt objects. The computer model is just used to validate possible explanations. This is almost exactly how Neptune and Uranus were discovered: by observing their effects on the orbits of the then-known planets.

    • Actually, yes this is based on observation of objects in kupiter belt. The article is a mess but worth reading.
    • I wonder how much mass this planet contributes to the dark matter issue?
      • I wonder how much mass this planet contributes to the dark matter issue?

        Well, since the first (and most significant?) evidence for dark matter was the fact that the outer portions of the arms of spiral galaxies were traveling much faster than the calculated total mass of those galaxies predicts they would (due to gravitational attraction), then, yeah - I'd say this fully debunks the evidence for dark matter ;-)

    • The evidence consists of the observations which inspired them to make the computer model.

      They already had the evidence; they just didn't know what it was evidence of. And then once the model predicted stuff like Sedna's orbit, they then had even more evidence: Sedna-and-friends. So that was an additional complex of evidence, for which they previously didn't know what it was evidence of.

      Let's say you drop an apple out of a tree. It falls. You don't know why. Then someone notices that most of the apples eve

  • Neil Degrasse Tyson is already working on having this soon-to-be planet declassified.
  • by tekrat ( 242117 ) on Wednesday January 20, 2016 @02:17PM (#51337753) Homepage Journal

    Space Cruiser Yamato (AKA Star Blazers in the USA), not only predicted Pluto's moon, but also a 10th planet -- I think it was called Brumus in 2nd Season (Comet Empire).

    Can't remember too much because it was more than 20 years since I saw the show, but so far, their space science is more true than any other TV show I can think of.

  • Some thoughts (Score:5, Interesting)

    by Rei ( 128717 ) on Wednesday January 20, 2016 @02:47PM (#51337965) Homepage

    An interesting thought. Even at its perihelion (1100 AU), helium won't be getting cold enough to condense out. But hydrogen probably will, condensing to planetwide hydrogen seas. Meaning that - combined with its lower mass - its atmospheric density at perihelion on top of that is probably surprisingly low. However, at aphelion its only about 400AU. That's probably not cold enough to condense hydrogen. So every 15000 years it would go from having hydrogen oceans and low atmospheric pressure to an ice surface under crazy pressures.

    What the heck do you call a planet like that?

    Such a large planet would certainly have the internal heat for tectonics and volcanism. But I'm still so baffled from trying to picture what such a planet would be like just from that first aspect that I can't even begin to imagine what effect the latter would have on it.

    Certainly a lot of energy in play here.

    • Re:Some thoughts (Score:5, Interesting)

      by Rei ( 128717 ) on Wednesday January 20, 2016 @03:37PM (#51338403) Homepage

      More thoughts.

      1) The atmosphere would be pure - 100% pure helium. The only thing that could contaminate it would be hydrogen, so if it's cold enough for it to be fully condensed out (no hydrogen clouds/rain), then it'll be a monoatomic gas. No clouds.

      2) The hydrogen seas would also be pure. There's almost nothing that can float in hydrogen - pretty much just foams gassed with helium, and that doesn't sound likely.

      3) Weird nuclear properties: helium is a perfect neutron moderator - it never undergoes neutron capture. It can undergo high energy reactions, but at lower energies, any neutron in helium will become fully thermalized, which - at those temperatures - would make everything interact with it at a very high cross section. Since only helium would be in the atmosphere, that would most likely be 3He. So I would expect 3He depletion.

      4) The day length would change when the hydrogen condensed out (like a ballerina pulling her arms in). I'm not sure off the top of my head of the effects of this mass redistribution on any orbital bodies, although I could picture, say, enhanced tidal heating due to the mass redistribution.

      5) There's an awful lot of potential non-hydrogen liquids which could exist under the liquid hydrogen (or under the H2/He atmosphere near aphelion) - nitrogen, carbon monoxide, methane and other hydrocarbons, neon, even water. It all depends on the pressure and temperature curves, which one couldn't even begin to speculate on at this point. Most of the latter could potentially form eutectics, but hydrogen is not prone to forming eutectics, so would make its own distinct surface layer.

      6) Lava flows of any type (silicate, cryolavas, whatever) would happen underneath the hydrogen ocean. Meaning pillowing. The boiloff of hydrogen could then expose these structures. What do pillow cryolavas formed under hydrogen look like? I haven't the foggiest.

      7) Any hot lavas (such as silicates) erupting into liquid hydrogen might have unusual chemistry (metal hydrides and the like? extensive hydrocarbon formation? silanes, stabilized by the low temperatures?). This would then be left exposed on the surface when the hydrogen boils off. That surface could be a really bizarre place.

      Any other thoughts?

    • by neo-mkrey ( 948389 ) on Wednesday January 20, 2016 @03:46PM (#51338509)
      Still sounds like a better place to live than Flint, Michigan, USA.
  • by slashmydots ( 2189826 ) on Wednesday January 20, 2016 @03:12PM (#51338181)
    This is what makes me think they're estimating the amount of matter in the universe incorrectly when it comes to the dark matter mathematical discrepancy. They can't even count our own planets correctly. I know the dark matter one is like 10:1 compared to visible light estimates but still, this really outlines how perpetually wrong astronomers are about everything.
    • Re:counting is fun (Score:4, Informative)

      by Rei ( 128717 ) on Wednesday January 20, 2016 @04:05PM (#51338671) Homepage

      The concept that dark matter wasn't normal matter wasn't arrived upon easily, it took until the 80s to really accept it. The thing is, even small objects still interact with EM radiation and such, and this has effects if you want to have enough of them to account for the missing mass. And these interactions just aren't observed, no matter what size bodies you assume. The closest you can get out of conventional matter is a hypothesis is for hypothetical objects called "macros", which is basically like tiny neutron stars.

      Honestly, dark matter doesn't bother me at all. What's so weird about the concept of particles having little to no interaction with certain fields? Now dark energy, that's some evil sorcery there....

    • Planets are a fraction of a percent of the mass of the solar system. When studying the structure of the galaxy astronomers could just use the sun and ignore the mass of all the planets and it wouldn't make much of a difference.

  • When it is actually found and they decide to name it, the new name needs to start with P so all the mnemonics that used to work with Pluto as #9 will work with this new planet.

    From Wikipedia:
    "My Very Educated Mother Just Served Us Nine Pizzas"
    "My Very Easy Method Just Shows Us Nine Planets"
    "My Very Efficient Memory Just Stores Up Nine Planets"
    "Mary's violet eyes make Johnny stay up nights, pondering"

    Persephone might work.

  • What does the solar system look like out at the distance of this suspected planet? One of the reasons for demoting Pluto to dwarf planet status was that it hadn't cleared it's neighbourhood so if this new object is orbiting in an area where there is lots of other materials then it shouldn't be called a planet either.

  • by riverat1 ( 1048260 ) on Wednesday January 20, 2016 @07:33PM (#51340475)

    Since we're on the subject of the Solar System a relatively rare phenomenon is occurring Jan. 20 to Feb. 20. [] All five of the easily visible planets (Mercury, Venus, Mars, Jupiter, Saturn) are visible together in the early morning sky. The last time that occurred was Dec./Jan. 2004/2005. They will be visible together again Aug. 13 to 19 but will be more easily seen in the Southern Hemisphere because Mercury and Venus will be difficult to see in the dusk sky.

COMPASS [for the CDC-6000 series] is the sort of assembler one expects from a corporation whose president codes in octal. -- J.N. Gray