The paper presenting the evidence for Planet Nine was published on 20 January 2016 in the Astronomical Journal, and written by Konstantin Batygin and Mike Brown.

We put the finishing touches on the paper at the Kona Brewing Company after a night at the Subaru telescope on Mauna Kea searching for Planet Nine.

 Konstantin is an Assistant Professor of Planetary Science at Caltech.

Mike is the Richard and Barbara Rosenberg Professor of Planetary Astronomy at Caltech.


  1. What a frabjous day! This is so very thrilling.

    Oh - you might like to know that Konstantin has lost an n in the above caption.

  2. Replies
    1. Good! But you've left it out in the Long and Winding History of Planet X... (I've left a comment there.)

      I know I'm a nit-picker, but it shows that I read what you write very, very closely, doesn't it? ;-)

    2. Well I had to bet the end from somewhere, didn't I?

    3. I should never comment via phone. That was
      "Well, I had to get the e from somewhere, didn't I?"

  3. Congratulations guys, fantastic research. The science is wonderful but the human story is just as compelling. What an exciting moment it must have been when the light bulb of discovery lit up with the realization that there really may be a giant planet in the far reaches of the solar system. And Dr. Brown, your not so subtle comment that "this is real planet" is sure to add fuel to the fire of the Brown vs. Stern feud, thus making the search for Planet Nine all the more fascinating. Here's hoping you find Planet Nine quickly!

  4. Serious question - Could Planet 9 be a small Black Hole?

    1. No. If it were, it have the mass of a sun and therefore the gravitational effect of a sun. Current calculations only allow for a Neptune sized object. Plus we'd probably notice a gravitational lensing effect on the stars in the general direction where we think the object is. Unless I missed something, we haven't noticed anything like that.

      Out of curiosity, why would you think it's a black hole?

  5. So it sounds like I would be wasting my time pointing my 155edfs in the general direction of planet 9!

  6. On Inside Science on bbc radio 4 you welcomed name submissions, so here's mine: Juno, the co-head goddess with Jupiter. We have a paucity of female-named solar system objects (sane ones anyway) and Juno has several reasons to recommend hers. She's large, distant, and cold despite her importance (because of her importance?) (like the script of Alien opens: 'The stars shine cold and remote like the love of God.' but I digress) It's easy to spell and remember--it even rhymes with Pluto and should therefore help mollify his mourners. Oh, and, apart from 'Earth' I say we DO have a nomenclature system for planets; they're all members or the Greco-Roman pantheon.