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Hunt For Ninth Planet Reveals Distant Solar System Objects (carnegiescience.edu) 154

Posted by BeauHD from the planet-9 dept.
schwit1 writes: Astronomers have discovered several new objects orbiting the Sun at extremely great distances beyond the orbit of Neptune. The most interesting new discovery is 2014 FE72: "2014 FE72 is the first distant Oort Cloud object found with an orbit entirely beyond Neptune," reports Carnegie Institution for Science. "It has an orbit that takes the object so far away from the Sun (some 3000 times farther than Earth) that it is likely being influenced by forces of gravity from beyond our Solar System such as other stars and the galactic tide. It is the first object observed at such a large distance." This research is being done as part of an effort to discover a very large planet, possibly as much as 15 times the mass of Earth, that the scientists have proposed that exists out there.
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Hunt For Ninth Planet Reveals Distant Solar System Objects More

Hunt For Ninth Planet Reveals Distant Solar System Objects

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  • Wow, and I thought the existing Sednoids were neat (Score:5, Interesting)

    by Rei ( 128717 ) on Tuesday August 30, 2016 @05:13AM (#52794891) Homepage

    A sednoid (2014 FE72) with an orbit out to 3000 AU (0,05 light years)? Talk about extreme, I would have been happy just for a couple more "ordinary" sednoids! But that's exactly the sort of thing you want to see if you're of the view that trying to group the universe into a neat collection of "stars" with "planets" orbiting them is oversimplistic. This lends credence to the notion that you're going to get shared debris between different stars, rogue planets that don't orbit stars, etc. Because with large bodies reaching that far out, it becomes pretty easy to perturb them to leave the solar system altogether.

    I have no clue what the discovery of 2013 FT28 is going to say about the possibility of an additional large planet in our solar system, but I look forward to the papers on it! Hopefully it won't rule one out, and will instead better constrain an orbit

    • Re:Wow, and I thought the existing Sednoids were n (Score:5, Interesting)

      by Rei ( 128717 ) on Tuesday August 30, 2016 @05:51AM (#52794965) Homepage

      Looking at their graph (since I don't see the perihelion stated anywhere), it looks to be about 60 AU (about double that of Neptune). That's some tremendous temperature changes on that body! The equilibrium temperatures are:

      ((1368 / D^2 - 3.127e-6) / 4 / 5.670e-8 ) ^ 0.25 ... where D is the distance in AU. So at perihelion it'd be about 36K, but at aphelion only about 5K.

      Now, this particular body is probably too small to retain significant hydrogen or helium, but you could imagine what it would be like for a large planetary one in such an orbit. It'd transition between being a hydrogen-ice planet with a helium mantle and water ice/rock core; and an ice giant like Uranus and Neptune. In its solid phase, its hydrogen-ice surface would be resurfaced entirely with every cycle and thus might be expected to be perfectly smooth, except because of the heat involved in the settling processes - and how low viscosity and structural integrity in general hydrogen ice has - I'd be willing to wager that you'd get helium volcanism and maybe even plate tectonics.

      It gets even weirder if a planet at such distances as this one's aphelion were to have a moon that loses helium vapour to its planet (perhaps, for example, on an eccentric orbit getting it back at each perihelion as the planet inflates, to repeat the cycle at the next aphelion). After all, even below the boiling point, there's always some vapour pressure for helium. If you're taking that vapour away, then you're looking at evaporative cooling, and you really don't need to lose it that fast to cool to below the cosmic microwave background (because radiative exchange is so slow at those temperatures) and thus to helium's lambda point. Now you have a body with superfluid helium on it, and all of the crazy weirdness that superfluids do.

      Back to our solar system - aka, a small body like 2014 FE72 - you're not going to have much hydrogen or helium. But even still, that crust is going to be going through some crazy thermal stresses at the very least. Also, neon - while not as common as hydrogen and helium, but should be more common in the outer reaches of our solar system than the inner - would pass through all three phases (melting point 24K, boiling point 27K at 1 bar; lower at reduced pressures). I wonder what sort of minerology neon would form? "Neonothermal" crystal veins, analogous to crystals in hydrothermal systems on Earth? :)

    • Re:Wow, and I thought the existing Sednoids were n (Score:4, Interesting)

      by K. S. Kyosuke ( 729550 ) on Tuesday August 30, 2016 @06:23AM (#52795041)

      This lends credence to the notion that you're going to get shared debris between different stars, rogue planets that don't orbit stars, etc.

      But how many? I don't think the process of exchange can be fast - if those bodies had galactic escape velocity, after all, they wouldn't stay here for long. So they must be comparatively slow. But the distances are still large (tens of thousands of AUs) and the volume in which they could be present is really big. Would a frequent exchange mean that most of this mass (or mess?) is actually in the interstellar space? And not in some neat belts close around stars?

      • Re:Wow, and I thought the existing Sednoids were n (Score:4, Interesting)

        by Rei ( 128717 ) on Tuesday August 30, 2016 @06:52AM (#52795141) Homepage

        I don't think the process of exchange can be fast - if those bodies had galactic escape velocity, after all, they wouldn't stay here for long

        They don't have escape velocity; they're stuck with us until something perturbs them. But the key point is that when something is that far out, it's very easy to perturb. And our stellar neighborhood is not static. Indeed, one of the alternative theories to explain the sednoids is that rather than a planet X, the orbits are due to one or more stellar passes nearby our solar system.

        So far we're still not seeing very far out, we're just barely spotting these things, and only when they're near perihelion. There's much more out there yet to discover, and so far all signs point to that our solar system doesn't just "stop" anywhere, it just keeps on going. Heck, we only know about the Oort cloud because comets have such distant aphelions.

        • I meant galactic escape velocity. Although I'm quite sure that lots of distant objects don't have escape velocity relative to the Sun either. (I should really get back into astrodynamics, though.)

      • Re: (Score:3)

        by Rei ( 128717 )

        Another thing I think argues for a universe full of planets: star frequency is proportional to size. The largest are rarest while the smallest are the most common. This continues all the way down: M class stars (red and brown dwarfs) make up 75% of the stars in the universe. We have more trouble estimating brown dwarf counts than red because they're not easy to observe, but they appear very abundant. But once you get below the cutoff for D-D fusion... we just can't see them. Why should we assume that t

        • Re: (Score:2)

          by Rei ( 128717 )

          (Pedantry warning: Yes, I know some red giants/supergiants fall into class M... they're a tiny percentage, I'm not talking about them)

        • Re: (Score:2, Informative)

          by Anonymous Coward

          well ... except that planetoids typically accrete around rocky objects after supernova, so without a previous star going nova, there's nothing to create the rocks to create the protoplanets to accrete planets. Consequently, the planet is full of gas clouds, and stars with significant planets pretty rare.

          • Re: (Score:2)

            by Rei ( 128717 )

            Thankfully we live in a universe long after big bang nucleosynthesis ;) There have been no shortage of stars ejecting heavier elements into space since then.

      • Re: (Score:2)

        by HiThere ( 15173 )

        How many? My guess is LOTS. You know how there are lots more small stars than large stars... well there's an equation that models that reasonably well as far down as we could expect to detect things. But I see no reason that just because something isn't self luminous it should be less likely to exist, so I expect lots more brown dwarfs than class M red dwarfs, and lots more loose planets than wandering brown dwarfs, and lots more asteroids than planets (and lots more small planets than large planets) and

    • 2014 FE72 has an aphelion distance of 4,275 AU +/- 20%. Since the orbit period is on the order of 280,000 years, and we have observed it for two, we will have to watch it a little longer to pin down the orbit exactly. Perihelion, at 36 AU, was in 1965, so it is still close to the perihelion distance. That's why we were able to find it. It is ~170 km in diameter, depending how light or dark the surface is.

      Source: http://www.minorplanetcenter.n... [minorplanetcenter.net]

  • If the singularity doesn't happen... (Score:5, Interesting)

    by wisebabo ( 638845 ) on Tuesday August 30, 2016 @05:54AM (#52794973) Journal

    and we never get anything better than fusion drives (and Bussard ramjets don't work), then maybe a high density of these "rogue" worlds will allow the (very slow) colonization of the galaxy.

    If there are roughly 1000x as many these large planetary bodies floating in interstellar space as there are stars, then perhaps it'll be feasible to travel to them in tens of years traveling at speeds achievable by nuclear fusion (hundredths of "C"). Then, using the resources there, colonies could be set up. Eventually, these will sprout new colonies, further pushing the boundaries of inhabited space until finally they reach a star.

    This scheme of colonization would be unlike anything the western world, even in the days of years long voyages via sailing ships, has known. Perhaps the closest would be the voyages of the far flung polynesians who managed to spread across the vastness of the pacific ocean over a period measured in centuries(?). If any of them made it to South America (some say they did), it would be like these future voyagers making it to the next star.

    Of course, we all hope for a Star Trek/Star Wars future with warp/hyperdrive bringing the stars within an afternoon's jaunt. Failing that I guess the runner up desirable future would be the hyper broadband interstellar communications network in which our downloaded selves could be digitally transferred at the speed of light to the next instancing hub (such as in Greg Egan stories of the post-singularity future).

    However if neither of those pan out and if we don't learn how to make/harness anti-matter, micro-blackholes, zero-point energy, giant laser driven solar sails or ??? then perhaps this is our most optimistic future.

    Maybe with immortality and suspended animation it won't be too bad. Slow trips around the galaxy indeed

    • Um, no. We will never achieve speeds of hundredths of C. The fastest we have achieved is 0.000542% c. And that was with a small probe. We aren't going anywhere.

      • We will never achieve speeds of hundredths of C.

        Earth is moving through space along with the rest of our local group at approximately 375 miles per second. I believe that works out to approximately 0.002C so that means we are almost moving at hundredths of C already without leaving the planet's surface.

        Second never is a very long time. We used to think that we would never exceed the speed of sound either. Hell, 150 years ago we weren't sure powered flight was possible. I see no reason why it is impossible in principle for us to travel considerably f

      • First of all, even just "the fastest we have achieved is 0.000542% c" and "we aren't going anywhere" are obviously mutually contradictory statements. Second, fusion allows for a few percent of c just fine. More is indeed problematic for a number of reasons but wasn't claimed, so that's a moot point.

      • Never is a long time. The fastest we can go with *current* technology is about 200 km/s, or 1/1500th c. (the speed you quoted as fastest is 1 mile/second, so there was a math error). Current technology is defined as a plasma or ion engine powered by a nuclear reactor, all of which currently exist, just not put together on a spaceship.

        Assuming at some point we build self-replicating factories in space, we can eventually use them to make a very powerful laser powered by the Sun, and use the Sun as a gravit

    • Comment removed based on user account deletion
      • I enjoyed KSR Mars series, but it was a joke in terms of reality. It is just Scifi.
        • Interestingly the 1 star reviews of that book you mentioned are all from Space Nutters. They just cannot grasp the fact that we aren't going to colonize the galaxy. They chose to give it a 1 star instead because they didn't agree with the premise. A bunch of nutjobs.

      • Though Aurora was a well-written defense of its thesis, the story is belied by its own posited scenario, which is that after several hundred years of colonizing and industrializing the solar system, man sends out the first generation starship. So if life is inextricably bound to the planet where it evolved, how could the solar system have ben settled in the first place?

        • Comment removed based on user account deletion
          • It is doubtful they could even travel back and forth. The radiation exposure itself would kill them. Of course some space nutter will just say "oh we will just fill the hull with unobtainium to shield the spacecraft" so it is like shouting in the wind. Meanwhile decades have gone by with no progress but the nutters still believe.

            • The unobtainium is called "Near Earth Asteroid materials", from the almost 15,000 known objects. Whatever orbit you want to go into, there will be some asteroids "near" in velocity terms. So you scrape some rock and dust off the surface of the asteroid, and use it to shield your "transit habitat" on the way to Mars or the Belt. The habitat doesn't stop, but goes in a repeating orbit, picking up new crew each time. During the trip, you process some of the rock into useful products, like fuel, oxygen, wate

              • Sure you just "scrape some dust and rock" off the surface of an asteriod. In space. Then you make fuel out of rock! No problem! Fuck, you space nutters are something else!

              • I had read somewhere that NASA's current plan for the Mars trips they are working on is to use the water for the trip as the shielding, and that it would only be needed when a solar storm happens, so most of the time, the standard aluminum shell should be enough shielding.

          • > IIRC, KSR depicted the colonized solar system as being dependent on resources from Earth, and workers on outer planets regularly returned to Earth to maintain their health.

            With respect to Mr. Robinson, he's just wrong. There is 7 times as much solar energy in high orbit as the average location on Earth, because there is no atmospheric absorption, night, or weather. Even at larger distances from the Sun, you can collect lots of energy using lightweight reflectors. With sufficient energy, you can proc

      • You might enjoy reading Kim Stanley Robinson's last novel Aurora which muses that life might be a planetary phenomenon

        Umm, you are aware that that is science FICTION right? Just because someone wrote an interesting story doesn't make it reality.

        KSR was spurred to write Aurora in part by the critical backlash against his idealistic vision of terraforming in his famous Mars trilogy of two decades ago

        "Critical backlash"? I read that (very boring) series and there were some interesting ideas in it but it wasn't exactly a scientific treatise. Anyone who took it as one pretty much missed the big picture rather badly.

        So if the Singularity never happens and human beings can never transition to machine bodies from biological ones, we're not going anywhere.

        And you have a categorical proof of this assertion? If so your Nobel prize awaits.

        • Yet you have unshakeable faith that humans will be colonizing other star systems. You should join a religion. There is a better chance of Jeebus returning to Earth, than us travelling to another star.
        • Comment removed based on user account deletion

    • "If there are roughly 1000x as many these large planetary bodies floating in interstellar space as there are stars, then perhaps it'll be feasible to travel to them in tens of years traveling at speeds achievable by nuclear fusion (hundredths of "C")."

      Which right away raises the question: who else might be already doing this?

      • No one, because it isn't possible to travel at the speed and distances involved to get there. And once you got there, it would just be a rock.

        • Re: (Score:2)

          by HiThere ( 15173 )

          You are misunderstanding his proposal. The thing is, this is NOT a fast way to get from star to star, it's a way to spread analogous to the way the Polynesians did. You travel only slightly faster than the local drift, because you need to mine it as you go past, but you don't slow down. You are traveling slightly faster (or slower?) than the local drift because you want to be continually getting new resources. In a way it's analogous to filter-feeding like an anemone...but in an area where you need to k

          • Ah, NOW I get it. You "get new resources" somehow and convert them to food, water, etc? And you need virtual reality and a decent AI (for unknown reasons). And ion rockets that run on rocks. What about automated cars? Do you need those too? You space nutters are truly nuts. You think life is like a video game.

            • Re: (Score:2)

              by HiThere ( 15173 )

              You need the virtual reality to siphon off energies that could otherwise lead to rebellion. You need AI to provide a consistent administration that will maintain a stable system over hundreds of human generations. You probably need a human figurehead in control, with the AI ensuring that the incorrect orders get carried out, and that all the correct orders get carried out. Probably most government decisions are optional, but we don't know enough about how societies run to be sure of that.

  • Comment removed (Score:3)

    by account_deleted ( 4530225 ) on Tuesday August 30, 2016 @07:21AM (#52795239)
    Comment removed based on user account deletion

    • Re:There is a 9th planet (Score:5, Interesting)

      by Rei ( 128717 ) on Tuesday August 30, 2016 @07:39AM (#52795315) Homepage

      You mean 10th. You forgot about Ceres.

      Under no reasonable standard is Pluto 9th. 10th, fine. I'd go out on a limb and argue at least 17th, also adding in the "planetary moons" that meet a hydrostatic definition even better than Pluto: Luna, Ganymede, Callisto, Europa, Io, Titan, and Triton. Using "planet" on the basis of of "body large enough to assume hydrostatic equilibrium but not undergo fusion" and moon as "body that orbits a planet".

      Hydrostatic equilibrium is a very meaningful definition. A body not in hydrostatic equilibrium is made of primitive materials; it's the sort of place you'd go to learn about the formation of our solar system. A body in hydrostatic equilibrium has experienced internal heating, movement of fluids, chemical reactions, etc. It's the sort of place you go to learn about geology and search for life.

      Or if you'd rather, you can apply the Captain Kirk test. Put it up alone by itself on a viewscreen. Would Captain Kirk say "Beam me down to that planet" or "Beam me down to that asteroid?" It's silly, but it's basically another way to say, "is the word functioning as normal people would use the word?" Of course, if there was another, bigger body in the background, they might say "beam me down to that moon". But we've all seen sci-fi where we're told that a body is a moon but people keep accidentally referring to it as a planet. The Forest Moon of Endor, for example. If it's a gigantic round thing, a part of us wants to call it a planet, even if we also know it's a moon. No reason not to just have them both as descriptive terms: a "planetary moon".

      (And IMHO, if there's anything we should be kicking out of the "planet" club, it should be the gas giants... followed next by the ice giants. Seriously, how much is Jupiter like Mars?)

      As for Stern, he once presented a rather interesting classification scheme (ironically, in the same paper as the Stern-Levison parameter was proposed). Basically, forget about all of these nouns, just have a good list of adjectives. You can have various things from sub-dwarf planet to super-giant planet to indicate the mass; prefixes like "gas" or "ice" or "rocky" to indicate the character: other adjectives to indicate its orbital parameters (including its "neighborhood" if you prefer), etc. Why limit yourself? Cite as many adjectives to describe it as are appropriate to the situation.

    • Re: (Score:2)

      by Kuukai ( 865890 )

      For historical purposes (recognizing that "historical" means "20th century" here), why not? For historical purposes, fire is an element and a totally random subset of seeds are called "nuts." Sure, Pluto was a tiny object known only because it was discovered completely by chance. But humans are super arbitrary. Alternatively, I propose we just name the new planet "Pluto" and the current Pluto "Old Pluto." Problem solved.

  • What the hell is the big deal with "planet"? (Score:3)

    by Opportunist ( 166417 ) on Tuesday August 30, 2016 @07:44AM (#52795343)

    Pluto is no planet!
    Why?
    Because it's not cleared its orbit.
    So?
    Well, we have found almost a dozen others out there like Pluto!
    So?
    We'd have to call all of them planets!
    SO?

    What the fuck is the big deal? I am still waiting for a really good reason that explains why "clearing its orbit" is so friggin' important. Technically, given its Trojans, Jupiter hasn't even done that. So let's call that biggest gasball outside the sun itself a planetoid.

    I can see the "has to be large enough to have enough gravity to get round". Ok. Just for the sake of having a lower limit in mass. I can of course see the "has to orbit the sun itself and not another object" so we can tell it apart from a moon (which gets our very own planet into rather hot water, considering that outside Pluto we have the biggest moon compared to planet mass, at what point do you have a dual-planet system rather than a planet-moon system? Probably when the common center of mass is outside both bodies, I'd say).

    But "clearing out the orbit"? C'mon, find a better reason if you want to keep the planet club exclusive and not include the likes of Pluto. I bet it's just 'cause you noticed that it's half-black, isn't it?

    • Re: (Score:2)

      by Rei ( 128717 )

      The most ridiculous thing about the "cleared its orbit" standard is... MOST planets didn't clear their orbit. Jupiter, and to a lesser extent Saturn, did. Particularly in the case of Mars. Mars does not dominate it's neighborhood, a fact clearly reflected by how low of a percentage of asteroids are in a Mars resonance vs. Jupiter. Mars has a significantly lower Stern-Levison parameter than Neptune, and yet Neptune has freaking Pluto in its neighborhood. And even if one wants to argue that Pluto is too

      • The only "good" reason I could think of is that they wanted to retain the formula "Rocky planets inside, gassy planets outside" and Pluto kinda messed with this. But with Pluto no longer being a planet, the order is restored.

        • > The only "good" reason I could think of is that they wanted to retain the
          > formula "Rocky planets inside, gassy planets outside" and Pluto kinda messed
          > with this. But with Pluto no longer being a planet, the order is restored.

          When Ceres was discovered, it was originally called a "planet". More and more bodies were discovered in a similar orbit. Rather than having thousands of "planets", the definition changed to make Ceres and friends "asteroids".

          Fast-forward a century or two. Uranus' orbit was

  • We haven't yet found the remote control in the couch, but we did found 3 socks, a bag of unopened Doritos only 1 month past the expiration date, $3.27 in change, a Zune, and a blue skirt.

  • Phsaw. Object 2014 FE72 in the TFA is stated as being at 3000 AU. The Oort cloud barely begins at 2000 AU [wikipedia.org] and may go out as far as 50,000 or even 200,000 AU. Granted these figures are more conjecture than precise measurements, but if even approximate, the object 2014 FE72 barely grazes the innermost edge of the Oort cloud, much less qualify as a "distant" Oort could object.

  • The universe. (Score:3)

    by malditaenvidia ( 4015209 ) on Tuesday August 30, 2016 @02:17PM (#52798239)
    When I was child, there were thought to be 9 planets. Now there are 90 planets.

    • According to the Minor Planet Center ( http://minorplanetcenter.net/ [minorplanetcenter.net] ) there are 717,000. A planet being anything that orbits the Sun. They come in three sizes, major planet, dwarf planet, and minor planet. There used to be only two sizes, but we added a new one to accommodate recent discoveries.

      Major planets are round, and dominate their orbit. Pluto doesn't qualify, because it's orbit crosses Neptune, which is 8,500 times more massive. In fact, Pluto is Neptune's bitch, being locked into a 3:2 orbi

      • Re: (Score:2)

        by Rei ( 128717 )

        These are what the IAU came up with, in a vote that was very controversial among its membership. An association dominated by astronomers, not planetary scientists, who were by and large against the decision. And a set of terminology that you can often find flatly ignored in scientific papers. Example [arxiv.org]. In short, the only group that the IAU is able to bludgeon into using their term is the general public (using the "We're scientists, if you don't use our term you're wrong and ignorant" gambit), not the sci

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