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Is this possible "giant planet' a hot topic in astronomy?

  1. Feb 14, 2016 #1
    Downloads are approaching 300,000 so somebody is interested. The 'planet', if it exists, is expected to have an 'appreciably eccentric' orbit. Is there any inventory of how many teams might be searching for this object??


    Konstantin Batygin1 and Michael E. Brown1

    Published 2016 January 20 • © 2016. The American Astronomical Society. All rights reserved. • The Astronomical Journal, Volume 151, Number 2

    "Recent analyses have shown that distant orbits within the scattered disk population of the Kuiper Belt exhibit an unexpected clustering in their respective arguments of perihelion. While several hypotheses have been put forward to explain this alignment, to date, a theoretical model that can successfully account for the observations remains elusive. In this work we show that the orbits of distant Kuiper Belt objects (KBOs) cluster not only in argument of perihelion, but also in physical space. We demonstrate that the perihelion positions and orbital planes of the objects are tightly confined and that such a clustering has only a probability of 0.007% to be due to chance, thus requiring a dynamical origin. We find that the observed orbital alignment can be maintained by a distant eccentric planet with mass [PLAIN]http://ej.iop.org/icons/Entities/gsim.gif10 [Broken] m⊕ whose orbit lies in approximately the same plane as those of the distant KBOs, but whose perihelion is 180° away from the perihelia of the minor bodies. In addition to accounting for the observed orbital alignment, the existence of such a planet naturally explains the presence of high-perihelion Sedna-like objects, as well as the known collection of high semimajor axis objects with inclinations between 60° and 150° whose origin was previously unclear. Continued analysis of both distant and highly inclined outer solar system objects provides the opportunity for testing our hypothesis as well as further constraining the orbital elements and mass of the distant planet.
    Last edited by a moderator: May 7, 2017
  2. jcsd
  3. Feb 19, 2016 #2
    Thanks for the post! This is an automated courtesy bump. Sorry you aren't generating responses at the moment. Do you have any further information, come to any new conclusions or is it possible to reword the post?
  4. Feb 19, 2016 #3
    For historical reasons I am interested in this subject and heard on a talk radio show that 'thousands of astronomers' were working on this. Sounded like a bit hype, so I thought I'd inquire. If experts here know of teams then I'd like to check on their progress from time to time.
  5. Feb 19, 2016 #4


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    This isn't something I'd even heard of before seeing your post. Unless you can find more papers on this same subject then I wouldn't put too much stock in the claim that "thousands of astronomers" are working on this.
  6. Feb 25, 2016 #5
    There is some talk but it seems to be relatively little "hype" about the discovery. According to what I have read its orbit is very large and its been very hard to track.


    I would say its of less concern then the large but not "planet sized" NEO,s or earths Trojan https://en.wikipedia.org/wiki/2010_TK7 Planetoids or (minor planets)

    There seems to be many pieces of space "rock" floating out there large enough to have some gravity, but not large enough to be called a "planet".
  7. Feb 25, 2016 #6
    Planet 9 is supposed to be 10 Earths in Mass.
    It's Diameter is probably greater than 10X ;
    especially if it's gaseous like Uranus.

    Something as big as Planet Nine should make Stars blink as it briefly eclipses their view from Earth.
    Wide Array low power telescopes take Time Lapse pictures which are scanned by computers
    to find small Near Earth Objects.
    The same technique will find Planet 9 pretty soon; if it's out there..

    It's biggest effect on Earth would be changing the orbits of those other Icy objects to approach closer to the Sun... imo
  8. Feb 25, 2016 #7
  9. Feb 26, 2016 #8
    And if it's a single body, its expected to be about 20 times further from the sun than Pluto. So we could call it "10 plus 10 equals 20".
    Apparently some think 'it' is instead a collection of smaller objects rather than a single large one. But it would be fun to have another planet: I wonder what paradigms, if any, that would confront about solar systems.
  10. Feb 26, 2016 #9
    Remember volume goes up as diameter cubed, if planet X had 10 times the diameter of earth but the same density it would mass 1000 times more than the Earth or three time Jupiter. Even at Uranus densities a planet 10 times heavier than Earth would only have a diameter of 3.5 times Earth.
  11. Feb 28, 2016 #10
    You're correct, the Diameter is probably smaller than I first imagined. Most of planet 9 is probably liquified or frozen solid 'gases'.

    Still seems like some Star will be seen to Dim or Disappear as Planet 9 slowly eclipses its view from Earth.

    This is how small Near Eath Objects and very Distant Large Planets are located as I understand it.
  12. Feb 28, 2016 #11


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    arXiv version

    Just a few objects have been found that way. More than thousand exoplants, but those dim the stars slightly for hours instead of blocking the light for a short time.
    Those occultations are very rare. An object the size of uranus would block light of a star for up to ~30 minutes if we look away from the sun. Longer times are possible under different angles. At 1000 AU, it blocks a tiny 10-13 of the full solid angle. If you take a picture of the sky every 30 minutes for 12 hours a day, and want a realistic chance to find it within 10 years, you have to monitor 100 million stars in every 30-minute slot. Order of magnitude estimate. Good luck.

    Gaia will measure parameters of about a billion stars, but only with (on average) 70 measurements per star, not with a full-sky image every 30 minutes. That gives a roughly 1% chance that this planet will occult one of those stars in one of the observations. And even if you have that, it is just a single observation - not sufficient to determine orbital parameters or anything else apart from the current position in the sky and some lower limit on the diameter.
  13. Feb 29, 2016 #12
    Thanks for Parameterizing the difficulties involved in Locating this hypothisized Planet9.

    Sounds like the Mathematicians will have to narrow the search area using Gravitational anaylsis.

    Also sounds like a High Resolution Space Based Telescope may be needed to provide enough background stars
    to increase the odds of observing an Occultation. Time on these telescopes is already dedicated to other projects.

    To clarify, the method I am discussing involves :
    Overlaying One Photo with a Negative Image taken at a later time
    to highlight Stars that Blink or Dim.

    On a side note. This reminds me of an observed Meteorite fall in West, Texas.
    It was seen by people but also caught on Dopler Weather Radar.
    Given the Sweep Rate of the Radar they were just Lucky to get a brief reading of direction and velocity.

    They also mentioned that Other unseen meteorites may have been caught on Doppler
    but nobody has looked back into the databases that I know of.

    Who gets to name this Planet9 if it is found?
    A Google search of 'Planet 9' is a poor Qualifier to pull up meaningful results.
    Last edited: Feb 29, 2016
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