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Evidence for 9th Planet Unveiled

A new planet ten times the mass of Earth deep in the outer system? That’s the word out of Caltech, where Konstantin Batygin and Mike Brown report the evidence from computer modeling and simulations, though no planet has yet been directly observed. The planet would orbit 20 times further from the Sun than Neptune, with an orbital period between 10,000 and 20,000 years.

“This would be a real ninth planet,” says Brown. “There have only been two true planets discovered since ancient times, and this would be a third. It’s a pretty substantial chunk of our solar system that’s still out there to be found, which is pretty exciting.”


Image: This artistic rendering shows the distant view from Planet Nine back towards the sun. The planet is thought to be gaseous, similar to Uranus and Neptune. Hypothetical lightning lights up the night side. Credit: Caltech/R. Hurt (IPAC).

From what we know so far, the planet would explain features in the Kuiper Belt, including the fact that from a list of thirteen of the most distant objects in the Belt, six of them follow elliptical orbits that point in the same direction in physical space, as this Caltech news release explains. Says Brown:

“It’s almost like having six hands on a clock all moving at different rates, and when you happen to look up, they’re all in exactly the same place,” says Brown. The odds of having that happen are something like 1 in 100, he says. But on top of that, the orbits of the six objects are also all tilted in the same way—pointing about 30 degrees downward in the same direction relative to the plane of the eight known planets. The probability of that happening is about 0.007 percent. “Basically it shouldn’t happen randomly,” Brown says. “So we thought something else must be shaping these orbits.”

A Kuiper Belt with 100 times the mass it has today could explain the phenomenon, but that’s obviously out. Simulations involving a massive planet in an anti-aligned orbit seemed to work, however. By anti-alignment, the researchers mean an orbit in which the planet’s perihelion is 180 degrees across from the perihelion of all other objects and known planets. Mean-motion resonance could keep Kuiper Belt objects from colliding with the planet and maintain the necessary alignment, with the new planet nudging KBOs to maintain the configuration. Says Batygin: “I had never seen anything like this in celestial mechanics.”


Image: A predicted consequence of Planet Nine is that a second set of confined objects should also exist. These objects are forced into positions at right angles to Planet Nine and into orbits that are perpendicular to the plane of the solar system. Five known objects (blue) fit this prediction precisely. Credit: Caltech/R. Hurt (IPAC) [Diagram was created using WorldWide Telescope.

Brown and Batygin are continuing to refine their simulations to learn more about the planet’s orbit and gravitational effects, while at the same time searching the sky for it. Remember that the orbit is only approximately known. It may well show up in images taken through previous surveys, though if in the most distant part of its orbit, large telescopes like Keck or the Subaru instrument on Mauna Kea may be needed to see it. “I would love to find it,” says Brown. “But I’d also be perfectly happy if someone else found it. That is why we’re publishing this paper. We hope that other people are going to get inspired and start searching.”

The paper, titled “Evidence for a Distant Giant Planet in the Solar System,” appears in the Astronomical Journal, published online 20 January 2016 (full text). Needless to say, more on this tomorrow.


Comments on this entry are closed.

  • Lionel January 20, 2016, 13:22

    Wow – if I’m not mistaken, Mike Brown has always been outspokenly skeptical when other researchers have advanced the idea of a distant super-earth in the past
    Whatever happens, this is clearly going to make waves

  • Tiens van Greuning January 20, 2016, 13:36

    Oh wouldn’t it be just the most excellent news ever if this planet turns out to be real?

    Being probably a super-earth in our Solar System, and probably one formed much nearer to the Sun and later ejected, I’m sure we would want to go and have a look-see.

    But at at least 200 AU chemical rockets will not cut it, if you want a mission time similar to NH’s. No, humanity would have to get creative and actually develop and test much more potent methods of propulsion, in stead of just talking about such.

    And once we actually have the means to get something to that sort of distance in a reasonable time, something like a few telescopes at our Sun’s gravitational focal points would probably seem much more feasible.

    • Tiens van Greuning January 21, 2016, 13:17

      Here’s a wild idea. By the time we actually take a photo of this planet, Hubble’s successor will probably already be up there, and they will be thinking of letting Hubble do a controlled re-entry.

      But why not give Hubble a good service, add some new instruments, and build your Deep Space Nine probe around this newly refurbished, very expensive 2.5m telescope which is already up there.

      Just think of the science you could already do on your way to this planet, which is likely to have loads of small moons in its vicinity, think how easy it would be to identify follow-up targets if you take your own Hubble with you, and then when this baby crosses 550 AU you just turn it around and do some decades worth of unbelievable science on any star that happen to pass behind the Sun’s grav lens….

      • Ashley Baldwin January 22, 2016, 20:27

        Sadly Hubble is showing its age and would be more expensive to refurbish than start from scratch. JWST can see to a respectably long wavelength of light but in a narrow field so is more likely to confirm than discover. The LSST ,8.4m , wide field scope is designed for just this purpose and although 8 years or so to launch that isn’t necessarily bad as it is going to be turning out terabytes of data so will need some time to develop the necessary clever software it will require to sift through its images looking for faint targets.( as with the SKA too)
        As to space telescopes. Nasa still have the “other” NRO 2.4m telescope sitting around which is already wide field and infrared . Perfect for the outer solar system and Kuiper belts. For only a fraction of JWST’s cost it could be kitted out with an imager, decent sensor array and spectrograph ( with a simple mechanical cooler to let it look further into the IR without expensive and time limiting liquid He) . An RTG for power ( Livermore have started making Pu238 again , and to heat some parts of it that need room temperature operation) and then send it out to Saturn /Sun L2 point for operation. Nearly nine AU further out than Earth and a whole lot nearer to Neptune and the Kuiper belt.

        • Jens Knudsen January 25, 2016, 15:24

          Are there any plans presently what to do with the NRO? Equipmentwise, it looks like an ‘easy’ way to get a very good facility going.

        • Jens Knudsen January 26, 2016, 16:13

          There is an article in Space.com about the NRO, dated January 21st. Nasa will begin working on it shortly. It is slated for launch in 2024!!

      • Infinite123Lifer January 25, 2016, 12:34

        Imagine … it would be a whole new launch. Fascinating!

  • ljk January 20, 2016, 13:40

    Of course there is already a blog up for this alleged object:


  • Mike January 20, 2016, 14:11

    Would a planet that size and that distant have been imaged by the WISE mission? Its image maybe sitting in the WISE data.

  • kamal ali January 20, 2016, 14:13

    Neptune is at 30AU. If this is x20 distant, thats 600AU: a good practice to visit as an interstellar precursor. Basically we’d be visiting something thats approximately 10x further than Pluto. To visit such a target , we’d have to use a propulsion method thats doable and not too far fetched. Just the perfect stepping stone. I really hope they find it and we visit it!

    • Giulio Prisco January 21, 2016, 4:13

      I thought the same. A planet 0.01 light years away would be the prefect stepping stone to the stars, close enough to be reachable with moderate improvements of today’s tech, but far enough to be considered as an interstellar destination.

  • kamal ali January 20, 2016, 14:17

    So exciting… 600AU is approx 3 light days.
    The next step would be to find a target that’s 1 light month ~ 5000AU.
    I guess that step would be for our next generation.
    But its essential to have stepping stones to 60,000 AU (1 LY).

  • Michael January 20, 2016, 14:18

    The missing fifth gas giant?

    • Scott Gordon January 22, 2016, 9:37

      Just what I was thinking.

      Computer simulations led to the conclusion that current arrangement of planets in the Solar System is easier to achieve if there was previously an extra (5th) gas giant planet (~ Uranus/Neptune sized) which was ejected to interstellar space by interactions with the other four.

      What if it wasn’t completely ejected and instead ended up in an odd orbit in the extreme outer solar system ? Would be good to hear how compatible this is with the original computer simulations.

  • Joshua Pepper January 20, 2016, 14:29

    This is very exciting, and is some tremendous work by the authors. But my biggest concern is why an object like this has not been directly observed. Even at a distance of several hundred AU, the planet should be bright enough in the near- and mid-IR that 2MASS or WISE should have detected it readily. And the groups that have been searching for nearby L and T dwarf stars have been combing those data sets for objects with unusual proper motions.

    • David Blank January 21, 2016, 5:20

      Joshua Pepper,

      If it was in or near the galactic plane, it could be in the 2MASS images,
      but not recognized because of confusion. Most brown dwarf searches have looked at the sky away from the galactic plane (b>20 degrees) for this reason. Confusion as you know is even a bigger issue with WISE data because of the lower resolution.

  • tchernik January 20, 2016, 14:49

    Nice. And this one, if confirmed, won’t be as easy to get rid of as Pluto.

    If it exists, text books would have to be re-written.

    And being a big one, it would require a suitably important Roman god/ess for giving it its name.

  • Eric S. January 20, 2016, 15:12

    Any chance this lines up w/ the recent ALMA potential find?

  • Tom Pliska January 20, 2016, 15:47

    Just idly speculating–I’m wondering what difference it would make if it were a super Earth rather than another Neptune. For detection, the latter would have a bigger disk per mass, but what would the difference be in terms of infra-red radiation?

  • ljk January 20, 2016, 15:52

    Eric S. said on January 20, 2016 at 15:12:

    “Any chance this lines up w/ the recent ALMA potential find?”

    Eric, is this what you are referring to:


  • Michael H. January 20, 2016, 15:56

    Could this supposed planet be an original member of this system that was pulled out due to the close passing of another star–like Scholz’s Star at 0.59 ly, HIP 85605 at 0.13ly, or Gamma Microscopii at 0.35ly? Or maybe our Sun grabbed it from a passing solar system?

    • Michael M January 23, 2016, 4:19

      Capture events are quite rare but not impossible, if a world was wondering through the solar systems early gas and dust forming disc momentum would have been lost that could have allowed capture.

  • Marc Longoria January 20, 2016, 16:10


    • Michael H. January 21, 2016, 4:51


      • Michael January 21, 2016, 13:03

        Nemesis, I think it should be named after a women, nothing could be so enigmatic and elusive and all the other planets named after males.

    • Larry January 23, 2016, 1:51


  • RobFlores January 20, 2016, 16:58

    Thinking of this world’s surface:

    We already know what happens to ice world beyond Neptune.
    Their atmosphere tend to collapse into frozen features.
    But that is assuming all the H2/He is bled away during it’s early

    BUT, a combination rocky/ice world would have more than 1G of
    gravity but not much more. Does the gravitational well and subsequent heating keep the planet out frozen state. I expect the answer maybe something similar to Pluto. a partial unfreezing when close approaching the sun.

    If this is a true terrestrial world with a mostly rocky core then I would expect
    that volcanism would resurface the planet melt the ice for a time, and then
    resume it’s slumber once the planets crust expels the interior heat. So
    a combination Venus/Pluto events. One melting induced by orbital distance and one melting induced by internal geophysical processes.

    What ever it is since WISE did not spot it, it’s surface is probably below the freezing point of hydrogen.

    • Michael January 21, 2016, 14:39

      ‘What ever it is since WISE did not spot it, it’s surface is probably below the freezing point of hydrogen.’

      This is unlikely even Neptune a few hundred kilometers down is above freezing. Any world over a mass of the earth will collect a large amount of hydrogen and helium due to the cold region of space.

      • Jens Knudsen January 23, 2016, 11:18

        Is there any chance it could harbour a substantial resource of helium- 3?

  • Frank Smith January 20, 2016, 17:26

    Somewhere Percival Lowell is smiling…

  • Securis January 20, 2016, 17:32

    @tchernik: There is only one possible name for that planet – Nibiru. ;P

  • Dave Moore January 20, 2016, 17:54

    I can see gravitational interaction with another gas giant giving this planet its large apohelion, but what mechanism would give it a large perihelion?

  • ljk January 20, 2016, 18:17

    The Planetary Society’s blog article on the subject, with lots of good links:


  • Joy January 20, 2016, 18:18

    @Joshua Pepper
    We really have no way of knowing what the IR spectrum of this object would be. If it was a rocky world, there would be enough U238 decay to keep it warm with active tectonics, including hot volcanoes. However, if what we have here is mainly an ice core with a gaseous envelope … I would expect a very, very low temperature. There would be precious little heat of formation left, minimal internal heating, and trivial solar heating. We might have to detect it by (gulp) reflected sunlight.
    Even so, we are talking about an object with a diameter perhaps 10x Triton’s, so even at 20x the distance with same albedo it would be roughly 1/4 as bright. So maybe a 15th magnitude object? Should have been photographed many times. But perhaps the proper motion is so small it has been missed. One would expect Gaia to catch it before the mission ends.

    • Scott Gordon January 26, 2016, 8:41


      I think you worked out how light it receives, not how much reaches Earth after reflecting off it. It drops off as 1/distance^2 both going TO the planet and going FROM the planet to whoever sees it (hence 1/distance^4 if you’re roughtly at the position of the Sun (close enough for Earth)).

      Something 20x as far from the Sun as Neptune would appear about 160,000 times fainter due to distance, from Earth (20*20*20*20) so that’s your starting point [multiple by whatever factors due to size and albedo]. This would make the figure 10*10/160,000 = 1/1600 th as bright as Triton .. a very different proposition to 1/4.

  • andy January 20, 2016, 18:32

    I’ve seen enough claims of evidence for various planetary candidates beyond Neptune that I can’t get too enthusiastic about this. Show us the planet.

  • ljk January 20, 2016, 19:00

    Not So Fast: Why There Likely Isn’t A Large Planet Beyond Pluto

    by Ethan Siegel, CONTRIBUTOR

    JAN 20, 2016 @ 03:21 PM


  • Carl January 20, 2016, 19:05

    There was a book published in the 1960s, ‘Nine Planets’. I can’t recall the author, but he went on flights of fancy beginning some chapters with imagined hazardous interplanetary ventures. His treatment of Pluto assumed a high mass to better account for the motions of Uranus and Neptune, while curiously dismissing those gas giants (ice giants were not a term at the time) as “unnecessary” and “the blank-faced idiots of the solar system”. The book had black-and-white renditions of conceptual paintings, and Pluto was depicted like an 8-ball with a bright spot. The caption had read that Pluto was seen only by the reflected highlight of the Sun from a great cold ocean surface… methane, perhaps… and its actual size was much greater than observed.

  • Al Jackson January 20, 2016, 19:12

    If the mass is really 10 Earth long term it could have an effect an the long period comet population, or at least a signature in the orbit catalog.


    Tracking of Voyager and Pioneer are very accurate wonder if something shows up there?

  • George King January 20, 2016, 20:06

    Re: getting there, believe that Gregory Matloff has outlined a close solar approach solar sail mission using graphene sails that would reach 1400 km/s. If my math is approximately correct (always touch and go on that), that could get a probe out to 600 AU in about three years or so.

    That should be doable with a sustained focus on that approach. As suggested in the comments above, finding another planet way out there might provide incentive to work the concept up to a higher TRL level.

    This may be the paper I’m thinking of:


    I’m pulling the 1400 km/s number from this popular press piece:


    Been trying to come up with a catchy name. Deep Space Nine maybe warrants a wry smirk, but is probably too many words for a planet name.

    Was trying to come up with a name that signified the coldest, farthest, coldest reaches.

    Still working on it.

  • George King January 20, 2016, 20:09

    Couldn’t get the link to work, here’s the description of the article:

    Matloff, G.L., “Graphene, the Ultimate Interstellar Solar Sail Material?” Journal of the British Interplanetary Society, vol. 65, p. 378-381

  • George King January 20, 2016, 20:11

    A name signifying the “coldest, farthest, darkest reaches,” that is.

  • David January 20, 2016, 21:01

    Brown Dwarf ?

    • Tiens van Greuning January 21, 2016, 13:03

      No, a brown dwarf would be several times the mass of Jupiter

  • Paul Gilster January 20, 2016, 21:20

    Carl writes:

    The book had black-and-white renditions of conceptual paintings, and Pluto was depicted like an 8-ball with a bright spot. The caption had read that Pluto was seen only by the reflected highlight of the Sun from a great cold ocean surface… methane, perhaps… and its actual size was much greater than observed.

    I remember that book because of the bizarre notion about Pluto’s reflected light. Had totally forgotten the name of the book. Thanks for reminding me of it.

  • George King January 20, 2016, 21:58

    How about Tartarus?

    According to the Wikipedia entry, Tartarus was as far below Hades in the Greek underworld as Earth was beneath the heavens:

    “As for the place, Hesiod asserts that a bronze anvil falling from heaven would fall nine days before it reached the earth. The anvil would take nine more days to fall from earth to Tartarus. In The Iliad (c. 700 BC), Zeus asserts that Tartarus is ‘as far beneath Hades as heaven is high above the earth.'”


    Sounds like the coldest, farthest, darkest place from the Sun in Greek mythology.

    • Ashley Baldwin January 22, 2016, 8:33

      “Prison of the Gods” . Far away, cold and sinister . Perfect name

  • Navin Weeraratne January 20, 2016, 23:40

    I hope it’s a gas planet (gas dwarf?). The Hydrogen (better, Heluim 3) will make it useful for refuelling and settlement. Could become a hub for the Outer Outer Solar System.

  • ijv January 21, 2016, 0:08

    @George King

    Deep Space Nine, may not cut it as a planet name, but it sounds great for a probe to whatever its name ends up being.

  • J. Jason Wentworth January 21, 2016, 4:00

    Two thoughts:

    If either of the Voyagers or New Horizons happen to be within imaging range of the hypothetical planet, between it and the Sun (one of the Voyagers photographed most of the planets from billions of miles away in the “family portrait” shots), the planet’s disc should be full–or nearly so–as seen from one or more of the spacecraft. If a rough position for the planet could be worked out, it should be possible for one or more of the probes to image it within several overlapping frames, and its motion over several days should be greater as viewed from the spacecraft, which would be closer to the planet than we are. (Whether either of the now electricity-deficient Voyagers could spare enough power to operate its TV system now is another matter, of course.) Also:

    Paul, that’s not such an unusual notion (Pluto appearing much smaller that its actual size due to specular reflection off a smooth, shiny surface) for that time, as I saw that idea mentioned in other books. Even as late as 1979, Robert M. Powers wrote in his book “Planetary Encounters” that Chiron might possibly be much larger than it appeared to be for a rather similar reason, perhaps being visible only by sunlight reflected from a small patch of light-colored material on an overall dark body.

  • Rob Henry January 21, 2016, 6:18

    @Joy wrote.
    “we are talking about an object with a diameter perhaps 10x Triton’s, so even at 20x the distance with same albedo it would be roughly 1/4 as bright.”

    Not so. True, a stars brightness tails off as the second power of distance but an outer planets magnitude declines as the fourth power as observed from the inner system. In your example, Triton would be 1600x brighter not 4x. This shows that even we Kiwis can make mistakes

  • Wojciech J January 21, 2016, 9:11

    This reminds me of the proposed Kuiper Telescope which would be used to study outer planets and Kuiper Belt objects.
    Perhaps with the discoveries on Pluto and this one, the proposal will be seen in new light and given more favourable treatment?
    Please see link below for the proposal made in 2015:

    • Ashley Baldwin January 21, 2016, 20:31

      I suggested a related suggestion to Philip Stahl at Nasa’s Marshall Space Centre . A deep space observatory stationed at the Saturn /Sun Lagrange 2 point and utilising the “other” NRO 2.4 m wide field infra red telescope Nasa got and which is currently used for technological research and back up for WFIRST ( as pre Decadel they have no idea or money to do anything with it . Will come in handy at some point though ) Perfect telescope for all Outer Giants and Kuiper belt and relatively cheap too. Decent imager, sensor array and spectrograph and off you go. A whole 8AU nearer Neptune and the Kuiper belt than any other scope.

  • Stephen January 21, 2016, 9:29

    If it is a brown dwarf it should be called Nemesis. If it is a gas dwarf it should be called Tartarus or Quirinus. If it is solid it should be called Nibiru.

  • Carl January 21, 2016, 9:30

    Terminus may be a good candidate name, keeping with Roman mythological names: https://en.wikipedia.org/wiki/Terminus_(god)

  • Andrew Higgins January 21, 2016, 10:06

    In absorbing the Batygin and Brown paper, it appears that if their Planet X actually exists, its orbit almost certainly crosses 550 AU. This is like a gift to Maccone’s FOCAL probe concept for a mission to the sun’s gravity lens. If you needed (another) raison d’être for a mission to go out to 550 AU, now you have it.

  • Nathan January 21, 2016, 10:17

    In Poul Anderson’s novel The Stars Are Also Fire, there (spoilers ahead) is a distant planet much beyond Pluto, which some of the characters in the book move to when they are escaping from the regime on Earth. The planet’s name was Proserpina. Proserpina is the Roman goddess of fertility who was abducted and taken to the underworld (cold and dark) by Hades/Pluto.

    • Janw Pool January 21, 2016, 16:07

      A very good suggestion, indeed!

    • Volucris January 21, 2016, 17:01

      Nice! If planet nine actually formed in inner solar system, and was later kicked out to cold outer reaches, this name would make as much sense as names based on Roman mythology ever will.

  • Harry R Ray January 21, 2016, 10:36

    This planet should have lots of tiny moons, and maybe a couple of big(Ceries sized) ones as well. The abstract states that the planet’s orbit is most likeky ECCENTRIC. Why is all of this important. Every 5,000 to 10,000 years, the planet will be EXACTLY 590 AU from the sun, where the sun becomes a LENSE STAR! Immagine the kind of astronomy that can be performed by FULLY AUTIMATED OBSERVATORIES on the moons!

    • JonW January 22, 2016, 12:29

      Harry, I believe lensing can occur at distances greater than 550 AU, not only at exactly the focal length–so the possibility for astronomy of that type would occur much more often than once every several millenia, as the likely orbit could take it out as far as 1200 AU. The notion of lense observatories on the moons of this world, if it (and they) exist, is a terrific one.

      • Paul Gilster January 22, 2016, 16:10

        Exactly right, JonW. The distance of 550 AU is a minimum, with continuing use of the instrument after that. There is no upper limit on the distance for FOCAL because, unlike the case with optical lenses, the gravity-focused radiation stays on the focal axis after 550 AU. In other words, the focal line extends to infinity. The disadvantage of the distance is offset by the fact that this proposed observing platform can do things no other telescope could handle. Ponder this, from Gregory Matloff’s Deep Space Probes book: For a FOCAL mission at the gravity lens, EM radiation from the occulted object is amplified by a factor of 108.

        • Jens Knudsen January 23, 2016, 12:58

          Does that mean ‘heavenly bodies’ ‘close’ to us can act as optical lenses, magnifying bodies much further out? For example a brown dwarf, or a gas giant halfway to the closest star? Maybe we can use the lensing technique without having to travel 550AU, as long as we are talking about a (space based) observatory that can stay on a suitable focal line?

  • Bynaus January 21, 2016, 10:59

    That would be a great find – a real stepping stone to the stars, like some have written above. We will likely need nuclear propulsion to get there, either nuclear-electric or nuclear-thermal. Such a new propulsion bus could then be of good use for other outer planet missions (think Neptune/Uranus/Pluto orbiters).

    WISE likely did not see it because even the longest wavelength observed by that mission (22 um) corresponds to a temperature of about 130 K. So if the planet is much colder than that, it will look very faint on WISE’s images, so WISE data can only be used to exclude the new planet on the closest part of its orbit. The “findplanetnine.com” website mentions this as well.

    One other good thing – at 600 AU, it would already be past the gravitational focus of the sun, so any mission there could perhaps double as a gravitational lense observatory (at least a test mission) after completion of the primary mission.

    The best name suggestion I have seen so far comes from Mike Browns father: Enatos. The Ninth in Greek. Wouldn’t that be cool. :)

    But let’s find it first!

    • Mark Zambelli January 21, 2016, 18:04

      Wouldn’t have to be Roman though?, although I do like Enatos :)

  • DJ Kaplan January 21, 2016, 14:06

    Am I the only one who sees the irony in the planet “X” (being the Roman numeral for “ten”) for this “ninth” planet?

  • Ashley Baldwin January 21, 2016, 14:10

    I’m glad that the professional astronomers are pontificating about whether it will or won’t be in preexisting images like 2MASS or WISE. There will no doubt be push back from some theorists on the math too ( though there have been other suggestions that abnormal KBO and EXKBO orbits have been explanined by such a planet for a while though no one has come out so specifically with evidence) that’s falsifiability for you . The University of Nice at the Cote D’azur ‘s respectable astrophysics department are backing the work too. LSST can be added to names of potential discoverers , JWST probably to confirm a wider field , longer term based imagery discovery . As to a name ? In this astronical labyrinth can only be :

  • ljk January 21, 2016, 15:00

    What about data from the other infrared satellites, including IRAS:


    Or ESA’s Infrared Space Observatory (ISO):


  • Mark Zambelli January 21, 2016, 16:54

    Wow… I never thought I’d live to see this age-old idea actually get some meat on it’s bones and now it looks like we may actually have something more than just pipedreams.

    Given the mass range from the model, is it just possible we may actually have that breed of creature that is a super-earth right in our system after all?… we’re no different, as it turns out (this, we know by now). Makes me ponder just how many potential-ETIs, having run their ‘exo’-searches, know a lot more about Sol’s retinue than the primitives on the third orb (special shout-out on 1.41Mhz to KIC 8462852, “hi”)

    One thing struck me about how more likely this model is… the quote is…

    “It’s almost like having six hands on a clock all moving at different rates, and when you happen to look up, they’re all in exactly the same place,” says Brown. The odds of having that happen are something like 1 in 100, he says.”

    To simplify by ‘actually’ talking about clock-hands, the odds of six independant hands aligning at, or ’rounding distance’ to, any ‘hour,’ is 12^6 = smidge under 3 million to one. If you don’t mind your hands pointing roughly within a two hour ‘zone’ it’s 6^6 = smidge over 46 and a half thousand. (A ‘smidge’ is roughly ‘a wee-bit’ (derivative: smidgeon)). I know I’m taking the limit of an analogy but where does the piddling 100 to 1 come from? Cautiousness perhaps?

    • JonW January 22, 2016, 12:26

      Mark, about your clock hands: the odds should only be 12^5, as the first one is for free. Looking at the graphic the tolerance is perhaps a bit wider than even your “two-hour zone”, which will get you down close to 100-to-1 (plus the man is naturally cautious).

  • Rob Henry January 21, 2016, 16:54

    Is there any way to reconcile a planet so far from the sun with one that can perturb the Kuiper belt, with the strong periodicity of 35 million years, as seen in the largest impacts?

    Surely, if we use aphelion precession to do so it should be much closer. I only ask because that would further fix its orbital parametres, especially for its current point of aphelion.

  • Eniac January 21, 2016, 17:30

    This would indeed be a great find. Paul, do you know of any attempt to explain the clustering in the orbital parameters of those Kuiper Belt objects by some sort of observational bias? To me that would have to be thoroughly ruled out before any exhileration can take place, uneasy or otherwise.

    • Paul Gilster January 21, 2016, 17:44

      Have not seen this studied yet but I’m sure it will be. Has anyone else here seen anything solid on observational bias?

      • Ashley Baldwin January 21, 2016, 20:14

        There no doubt will be . But this is all their so far with some in depth and prolonged math. I’m sure faults will be sought and alternatives considered by other theorists on study ,in the spirit of falsifiability ,but it’s too soon for that yet. The obvious thing I can see is that the sample of KBO objects cited to explain the orbit is just six which is a low sample size . Although the odds of the effect occurring by chance are described as being just 7 in 1000 this is based on some quite basic statistics done by Brown himself. Not anything like the detail employed in the mechanics math he is more familiar with.

  • Al Jackson January 21, 2016, 21:36


    I wonder about the infrared too. There is a problem if it is in the plane of the solar system, infrared brightness of the zodiacal cloud can mask Kuiper belt objects.