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Curious Tilt of the Sun Traced To Undiscovered Planet (spacedaily.com)

An anonymous reader writes: Planet Nine - the undiscovered planet at the edge of the solar system that was predicted by the work of Caltech's Konstantin Batygin and Mike Brown in January 2016 -- appears to be responsible for the unusual tilt of the Sun, according to a new study. The large and distant planet may be adding a wobble to the solar system, giving the appearance that the Sun is tilted slightly. "Because Planet Nine is so massive and has an orbit tilted compared to the other planets, the solar system has no choice but to slowly twist out of alignment," says Elizabeth Bailey, a graduate student at Caltech and lead author of a study announcing the discovery. All of the planets orbit in a flat plane with respect to the Sun, roughly within a couple degrees of each other. That plane, however, rotates at a six-degree tilt with respect to the Sun -- giving the appearance that the Sun itself is cocked off at an angle. Until now, no one had found a compelling explanation to produce such an effect. "It's such a deep-rooted mystery and so difficult to explain that people just don't talk about it," says Brown, the Richard and Barbara Rosenberg Professor of Planetary Astronomy.

17 of 232 comments (clear)

  1. Just curious... by XxtraLarGe · · Score: 4, Interesting

    How is it that we have an undiscovered planet in our solar system, yet we're able to find earth-like planets orbiting stars that are light-years away?

    --
    Taking guns away from the 99% gives the 1% 100% of the power.
    1. Re:Just curious... by Maritz · · Score: 5, Insightful

      The far away ones are seen either with a wobble in the star (shows up as redshift/blueshift on a spectrograph) or the planet occludes the star and makes it dim measurably. That means the planet has to be in line of sight of the star. This planet can't be in line of sight between us and the sun, because it's far out. If it exists, of course.

      --
      I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
    2. Re:Just curious... by Anonymous Coward · · Score: 4, Informative

      How is it that we have an undiscovered planet in our solar system, yet we're able to find earth-like planets orbiting stars that are light-years away?

      Most of those exoplanets are quite close to their respective stars, making them much easier to spot. On the other hand this planet is so far out and moving so slowly in its giant orbit that its difficult to spot it even moving and that's if you're lucky to be watching the spot it is currently in for a long time. The original discovery of Pluto was a happy accident in many ways.

    3. Re:Just curious... by plopez · · Score: 3, Insightful

      Possibly due to perspective. If a solar system is far away, you can observe all of it. If an object is in the solar system *and* out of the elliptic it may well be hidden. The location of the other planet, which may have an orbital period of centuries, has to be in the correct place to be seen and you need to be looking for it. Just guessing.

      Now that there is evidence of a large object outside the elliptic I'm sure someone will try to calculate the period and approximate location of it. The fact it is out of the elliptic may explain why some comets are out of the elliptic.

      By the way, nice sig.

      --
      putting the 'B' in LGBTQ+
    4. Re:Just curious... by Anonymous Coward · · Score: 5, Funny

      The same way we can observe the ass of that girl 3 rows in front during our astronomy lecture, but we can't see our own ass even if we're talking out of it.

    5. Re:Just curious... by myrdos2 · · Score: 4, Informative

      XKCD has a good image to explain this.

    6. Re:Just curious... by Lumpy · · Score: 3, Informative

      And that is assuming it's a bright object reflecting a LOT of light from a very distant sun. If this thing is dark in color at all, the lumens available out at where they guess it is...

      One astrophysicist basically said, IT would be easier to spot a flashlight that is on and pointed at the earth out in the OOORT cloud than to directly observe a planet out there. They need to look for stars that are being occluded and see if we can create a dataset, but if it is beyond the oort cloud, the orbital period may be measured in 1000's of years and will be even hard yet to detect

      --
      Do not look at laser with remaining good eye.
    7. Re:Just curious... by Kozar_The_Malignant · · Score: 4, Informative

      Here's what I get from the reporting on the original article by Batygin and Brown. Given the data, Planet Nine's orbital path is pretty well known. It is, however, way out there, which means that there is a lot of orbital length to search. The data do not give any hint as to where on the orbit Planet Nine might be. B&B speculate that it is not on the part of the orbital path that brings it closest to the sun, because there are good odds that all of the comet hunting scopes in the world would have spotted it by now. A good amount of telescope time is now being spent searching the further reaches of the orbit, and my guess is that it will be found within five years. If it exists, of course.

      --
      Some mornings it's hardly worth chewing through the restraints to get out of bed.
    8. Re:Just curious... by XxtraLarGe · · Score: 3, Insightful

      Why someone would mark a perfectly valid question like this as "overrated"?

      Because someone who doesn't like me has mod points. I've seen many of my comments modded down across several different threads. From what I understand, by modding someone overrated, your mod can't be metamoderated, so you don't lose moderation opportunities. But, it's just a message board, so it really doesn't bother me. I've got "karma" to burn. One of the reasons I always quote a person I'm replying to: If someone is modded down below the threshold, people will still know what my reply is about.

      --
      Taking guns away from the 99% gives the 1% 100% of the power.
  2. Re:Back to 9 Planets by Maritz · · Score: 5, Funny

    Sorry, Pluto is taken.

    How about Pluto1088549?

    --
    I do not want your cheap brainburning drugs. They are useless for work. And I am a working man today.
  3. Re:the sun is round how is it tilted by TFlan91 · · Score: 3, Insightful

    The Earth is round and also tilted... same concept.

  4. Say this aloud: "It's so massive..." by starglider29a · · Score: 4, Interesting

    "How massive is it?"
    "It's so massive that even at an insane distance, this Oort Cloud body can out-twist the masses of both Jupiter AND Saturn."

    Wait? How massive is it? How is it able to tilt the axis of the sun, since tilting an axis is a TIDAL action? IMHO (as a degreed rocket scientist) that Occam's Razor would indicate that it's easier to shift the orbital planes of the planets, rather than tidally torque the sun. Remember, for the tidal action, the Planet IX must be very close to Sol to work its magic.

    1. Re:Say this aloud: "It's so massive..." by mysticgoat · · Score: 4, Interesting

      A more careful reading of the article reveals that what is being tilted is the plane of the ecliptic. From a geocentric point of view, that appears to be a tilt of the Sun's axis, but to an observer outside the solar system, it is the plane of the orbits of all the known "non-dwarf" planets that is tilted. (IIRC, Pluto's orbit is outside the plane of the ecliptic-- which is part of the reason it took so long to find it after the maths showed it must exist.)

      Do we have enough data to estimate the orbital period of Planet IX? If so, it may be possible to correlate its changing angle to the plane of the ecliptic with long term changes in Earth climates. It would seem that during the thousands of years when Planet IX is near the plane of the ecliptic, the Earth's orbit would become more oval. Currently Earth is closest to the Sun (and moving faster in its orbit) around January 3, give or take a day; and most distant around July 3 (moving most slowly in its orbit). This causes Summer in the northern hemisphere to be around 4 days longer than Summer in the southern hemisphere. If Planet IX can cause a tilt of the planetary orbits at this time, then when it is in line with the plane of the ecliptic the Earth should see northern Summers significantly longer than southern Summers (and southern Winters longer than northern Winters).

  5. Just don't call it LV-426 by swb · · Score: 3, Funny

    That would be a bad omen.

  6. Re:the sun is round how is it tilted by Opyros · · Score: 3, Insightful

    Well, neither one is perfectly round; both are oblate spheroids, though this is trickier to measure in the case of the Sun.

  7. Re:Global Warming is due to 9th planet!! by narcc · · Score: 5, Funny

    We can do better:

    The mysterious 9th planet was caused by Climate Change!

  8. Re:If they can observe its gravitational effect... by Anonymous Coward · · Score: 3, Insightful

    Too many variables. The mass of the planet. Its angular tilt. Its angular path/velocity. They don't know exactly where to look. Computer modelling suggested the existence of this planet, but even if we're able to predict its orbital path correctly that's still going to be a literal 360 degree arc of the sky needing to be searched. Always assuming of course that the purported ninth planet isn't currently occluded by the Sun.
    Something as far out as this is purported to be is going to be nearly impossible to spot. It's not getting any light from the Sun to speak of, so it'll be visually black. It's also far enough out that it will be too small to occlude anything visually, and any gravitational lensing it produces would be insignificant against the background.
    We're not going to find this without a major event happening. Something like a rogue asteroid detected swinging in towards the sun from somewhere out in the Oort cloud. Something like that, angled from 6 degrees away from the ecliptic, would suggest gravitational deflection from this ninth planet, and would actually give us one specific direction to search in.