Talk:Planet Nine/Archive 3

Planet X
Currently the article does absolutely nothing to clarify that this is not "Planet X" at least in terms of what was the term originally intended. However, at least 5 refs currently in the title use this name. Nergaal (talk) 20:45, 16 February 2016 (UTC)
 * We're not referencing those citations for their erroneous information. Why do we need to say that this is not Planet X? We haven't had to mention that Mars isn't Venus, have we?  Serendi pod ous  21:27, 16 February 2016 (UTC)
 * Planet X was a hypothetical planet beyond Neptune, and Planet Nine is also a hypothetical planet beyond Neptune. People might confuse the two? As for Mars not being Venus, do you understand the concept of a straw man? I suggest you simply ask questions and make whatever point(s) you want to make rather than talking silly.  nagual  design   21:35, 16 February 2016 (UTC)
 * Trujillo & sheppard referred to Planet X, but Carlos & co didn't suggest any names because their model required more than 1 planet/minor-planets. we anyway have appropriate links to Planet X from different sections, so it is not an issue to me J mareeswaran (talk) 12:37, 22 February 2016 (UTC)
 * Do we have to say that it also isn't every other hypothetical planet beyond Neptune ever proposed? Look, I get it (kinda); Planet X is an overused term and is confused in the media. But that doesn't mean we have to give it prominence in this article. Or if we do, we should at least connect it to our topic in a sensible fashion. I seem to recall an interview with Brown/Batygin saying that they chose the name "Planet Nine" specifically to prevent it being called "Planet X". That would be good to include if we could find the source.  Serendi pod ous  04:38, 17 February 2016 (UTC)
 * The point is not to give it prominence, but to at least clarify the role of "X" since it is pretty clear that B&B specifically did not want to use it. Nergaal (talk) 05:25, 17 February 2016 (UTC)
 * If we could find a citation for that, that would be great.  Serendi pod ous  05:39, 17 February 2016 (UTC)

Path in sky
In a recent interview a plot of the predicted path of Planet Nine was shown overlaying the constellations and the Milky Way, starting at 4205. Agmartin (talk) 19:26, 20 February 2016 (UTC)
 * Indeed. There was a low resolution version without a stellar background in their paper. This is much more solid and specific. Someone needs to check copyright on if we can use that image. Sounds like someone just took a map of the sky and superimposed it on the chart in the paper. Totally doable. --Smkolins (talk) 21:22, 20 February 2016 (UTC)
 * I did notice they didn't talk about the bootstrap problem of it explains other things getting out that far and oriented but not how it ended up there. That would have been a good question - though it was nice to hear the heliosphere question. --Smkolins (talk) 21:23, 20 February 2016 (UTC)
 * The video says it could be near Orion if near Aphelion. Tom Ruen (talk) 03:19, 21 February 2016 (UTC)
 * Yeah that's already in the article. But if we can get the graphic it is far more encomapssing - though perhaps annotated with region of the aphelion and perihelion…. --Smkolins (talk) 03:35, 21 February 2016 (UTC)
 * I updated my simulator for a newly added Longitude of ascending node estimate in the table. So we can simulate Planet 9 in the central milky way, with the sun in Serpents. I added a second image of P9s motion in sky across Orion seen from earth. Tom Ruen (talk) 03:58, 21 February 2016 (UTC)
 * If you look at they have a RA/Dec chart as well as a distance chart and others.  The idea is to superimpose that RA/Dec chart on the night sky, label roughly perihelion/aphelion, the ecliptic of the inner planets, the Milky Way and at least a few key constellations related to the path of the P9. --Smkolins (talk) 13:46, 21 February 2016 (UTC)
 * Here's one more image attempt. I saw Scorpio at the bottom of the image at blog, image . I picked a date that mostly matched the sun's position, while my sun was a bit more north in Ophiuchus since the sample orbital parameters I used are slightly different. The sun would be -11.6 magnitude, many times brighter than Venus from earth, but dimmer than a full moon, while visually a point light source at 1.8" diameter (from 1040AUs). I added a second image below showing the motion of P9 in this orbit, seen from earth from year 1000 to 3000 AD. Tom Ruen (talk) 19:32, 21 February 2016 (UTC)
 * Planet_nine_artistic_plain2.pngPlanet_nine_path_in_orion2.png

Here's P9 sphere dropped onto an actual milky way view of the sky,similar to the original simulation, and a symbolic yellow sun in the upper right. There's no "correct" way to draw a -11.5 magnitude star for the sun and in space there's no atmosphere to blur the imaginary halo glow around it. Tom Ruen (talk) 21:57, 21 February 2016 (UTC)
 * Actually rethinking, perhaps dust in the solar system itself would create a faint glowing halo around the sun, but I don't know if that's the reasoning on the CalTech image sun. Tom Ruen (talk) 23:17, 21 February 2016 (UTC)
 * Planet nine artistic plain.png
 * I decided to be bold and replaced the low quality Celestia rendering File:Planet_Nine_in_Celestia.png with this one. I'm not committed to it, but I think its closer to what we want. Tom Ruen (talk) 22:16, 21 February 2016 (UTC)

Link to the overlayed path which was posted in the where is planet nine thread. Agmartin (talk) 19:25, 24 February 2016 (UTC)
 * Can anyone get in contact with him about uploading it to wikipedia? --Smkolins (talk) 13:38, 25 February 2016 (UTC)
 * now I'm having the idea of making it an animated gif slowly swapping between noting perihelion/aphelion regions, regions excluded by various searches, region suggested by the Cassini analysis, etc.--Smkolins (talk) 13:41, 25 February 2016 (UTC)

Probable location
What of this? Constraints on the location of a possible 9th planet derived from the Cassini data, Astronomy & Astrophysics manuscript no. FiengaLaskar2016R5, February 19, 2016. Does this seem reliable? Jehochman Talk 04:51, 24 February 2016 (UTC)


 * I edited that addition a bit, and for once actually tried to check the reference properly. I had to remove the sentence "At this location Planet Nine would be approximately 630 AU from the sun". The only relevant thing I could find in the article was a diagram that clearly showed this point as less than 600 AU from the sun. --Ørjan (talk) 13:57, 24 February 2016 (UTC)


 * In figure 6 of the paper, those are X-Y coordinates. Y is about 550, and X is about -300.  Applying simple geometry, (550^2+300^2)^0.5 = 626.  I rounded to 630, but if you prefer, we could round to 600 so as not to overstate the accuracy. Jehochman Talk 14:01, 24 February 2016 (UTC)


 * Argh, never mind me, I misread and looked only at Y. Back to just checking typos and formatting... --Ørjan (talk) 14:08, 24 February 2016 (UTC)


 * A couple of possible issues with their predicted location 1) They appear to be using the 'best fit' orbital elements from the paper in their analysis. What would happen to their predicted position if they used different orbital elements? 2) There is a large uncertain region where its perturbations wouldn't be detected. This covers much of the region without archived data to search. Agmartin (talk) 19:19, 24 February 2016 (UTC)


 * The basic orbit is pretty well known. what is not known is "where" it is on that orbit. It could be 630AU or 1200AU. -- Kheider (talk) 15:30, 26 February 2016 (UTC)

Imaginary views from Planet nine looking back at sun
We have at least two candidates for images, the left one a mixture of a real sky and overlaid planet and sun, while the right central image is pure Celestia, less dramatic and without clear geometry. You can see I prefer the left one, but I'm not committed to any specific final image. Tom Ruen (talk) 02:09, 26 February 2016 (UTC)
 * Planet in Celestia is modeled on all orbital parameters proposed by Brown (see here). Complied with distance to the Sun, size of planet, surface and expected location. The first picture is less accurate, The sun is too large, and the Milky Way is too bright. Википравитель (talk) 15:22, 26 February 2016 (UTC)
 * I'm not sure how you get that the Sun in the first image is too large (its smaller, but a bit brighter, than the second image) or that the Milky Way is too bright (its taken from an actual photograph). — Huntster (t @ c) 19:06, 26 February 2016 (UTC)
 * It does not matter, with real photos Milky Way or not (the second also with the real). Important brightness. Galaxy dim for the naked eye, including in outer space. The size of the Sun on the first picture as if from the orbit of Neptune or Pluto and even closer. Википравитель (talk) 19:20, 26 February 2016 (UTC)
 * Um, the second is entirely computer generated in Celestia as far as I'm aware. If the first image's Sun is from the orbit of Neptune, the second is from *much* closer in still. It is visibly larger. — Huntster (t @ c) 21:18, 26 February 2016 (UTC)
 * I'm not sure what Википравитель means by the size of the Sun either. Or the brightness. These things are relative. The Sun, from the predicted distance of P9, should be about 10 stops brighter than Antares, and almost point-like in its apparent diameter. Using my copy of Celestia the view looks something like this, with the orbit of Neptune showing. The view is from 0.016689 ly away, or around 1055 AU, as that's about as accurate as I could get. Bear in mind that the apparent diameter of the planet could be made considerably larger or smaller just by moving the POV a few thousand kilometers without noticeably affecting the background, and the field of view could be altered without affecting the relative sizes. Even moving closer to or further from the Sun by several AU has a marginal effect on the view.
 * If you'd like me to move the Sun to a different position I'd be happy to do that, but I think we'd be getting a little carried away with ourselves if we claimed to know the 'actual position' of a hypothetical planet. Similarly, if you think the Sun should be relatively brighter or dimmer I'd be happy to oblige. I was using artistic license, along with my experience with photography, to judge the amount of lens flare.
 * Whichever one we use can we please remove it from the infobox? Oh, and props to Википравитель for aligning P9's rotational axis with the rest of the Solar System, more or less. Something which the original Caltech version neglected (they essentially had P9 rotating on its side, like Uranus).  nagual  design   01:01, 27 February 2016 (UTC)
 * Here's one more candidate I'll offer (third image from left), not to say better than User:Nagualdesign's (I can't do fancy suns), but I took the same File:ESO - Milky Way.jpg background, but a larger sky area, closer to CalTech's view. But I confess I do like an artistic image in the infobox, AND if we don't have SOMETHING there, people are going to keep adding pictures there until the cows come home anyway. (And I don't know if we can guess the rotational axis at all given Uranus's tilt, and a known wild history of P9 to fling it out there.) Tom Ruen (talk) 07:14, 27 February 2016 (UTC)
 * I do not understand what for all this? I modeled the planet on hypothetical parameters Brown and Batygin, without any fiction with Sun or Milky Way. The Sun looks like it should look - distant star with glare. What do you still need? Third picture is nonsense. Википравитель (talk) 07:30, 27 February 2016 (UTC)
 * The Celestia picture is simply poor quality. I can't recognize a single star or constellation in that fake milky way field. Your sun is barely brighter than the milky way. The inner solar system planets should be completely invisible. Tom Ruen (talk) 07:41, 27 February 2016 (UTC)
 * Rave! The Sun at this distance can not be too bright. Even with Sedna it is impossible to see how the disc. A ninth planet much farther. And where did you see in the screenshot the inner planets? They were not there at all. The fact that you can not recognize the stars - it's your problem. Википравитель (talk) 07:48, 27 February 2016 (UTC)
 * I calculate at 1000AU, the sun will be about -11.5 magnitude, that's 600 times brighter than Antares. You can decide how to best represent that brightness, but in an exposure long enough to show the milky way, its going to dominate the sky. Tom Ruen (talk) 07:58, 27 February 2016 (UTC)
 * Antares less brighter Sun. Just Antares do not hit the shot, it's a little more to the right. Celestia view assumes that there is no exposure. In short, I am my image will not impose. He had already applied in The Russian and Japanese Wiki. Википравитель (talk) 08:04, 27 February 2016 (UTC)
 * Myself, I'm working with the geometry from the CalTech image,, reproduced here File:Planet nine artistic plain2.png. Tom Ruen (talk) 08:14, 27 February 2016 (UTC)

Okay, I have updated the image above as well as the labelled version so that the Sun appears in the same position as in the Caltech image. Since the background image is now 36% smaller the circle of confusion is smaller, and so I have made the Sun 36% smaller also. I've also added the orbit of Neptune to the labelled version, which arguably conveys much more information about the distance from P9 to the Sun than any amount of careful lighting. As for removing the image from the infobox, I would suggest it be replaced with the orbital diagram that forms the crux of the Planet Nine hypothesis. Regards,  nagual  design   11:06, 27 February 2016 (UTC)
 * I like it! In fact I actually prefer the labeled one with Neptune's orbit for scale. Or perhaps just adding Neptune's orbit to the unlabeled one is visually instructive. Tom Ruen (talk) 11:44, 27 February 2016 (UTC)
 * I cropped in Neptune's orbit to the unlabeled one. (p.s. I tried Neptune's orbit in my program, but it's actually different, shows the retrograde loops on fixed stars! Poor little 16th magnitude, 0.06" diameter Neptune. You'd have to carry a good telescope to P9, or one of its hopeful moons, to view it! Jupiter would be better at 10th magnitude.) Tom Ruen (talk) 12:00, 27 February 2016 (UTC)
 * P.s. It would be fun to see Voyager 1 and 2's trajectories in a view like this, given they are the furthest objects Humans have sent into space, and still under 150AUs from the sun.  Tom Ruen (talk) 13:35, 27 February 2016 (UTC)
 * Silly me, I never added hyperbolic orbital parameters to my program, although Voyager 1 and 2 are here. Tom Ruen (talk) 14:24, 27 February 2016 (UTC)
 * POST-SATURN VOYAGER 1 Epoch = 1/1/91, a = -480,926,000 e = 3.724716 i = 35.762854 OM = 178.197845 o = -21.671355 M = 688.967795
 * POST-NEPTUNE VOYAGER 2 Epoch = 1/1/91, a = -601,124,000  e = 6.284578  i = 78.810177  OM = 100.934989  o = 130.043962  M = 342.970736
 * or Pioneer 10 which is actually (if roughly of course) headed in the direction of aphelion…--Smkolins (talk) 16:31, 27 February 2016 (UTC)
 * Looks like they're all here. :) Tom Ruen (talk) 16:35, 27 February 2016 (UTC)

Image
Who made the image? Thank you for making it. I like the orbit of Neptune for scale. Would you be willing to take a request? Would you consider removing the lens flare? Jehochman Talk 12:56, 1 March 2016 (UTC)
 * User:Nagualdesign made it. I agree, the light ring is confusing, and someone might think its something real, like the Kuiper belt or whatever. Tom Ruen (talk) 14:07, 1 March 2016 (UTC)
 * Fair point. I had actually stopped the lens flare from 'overlapping' the planet as I thought people might wonder what all the funny circles were. The reason I included it in the first place was an attempt to show that the Sun would be overexposed in an image which showed the Milky Way (the Sun would be 10 stops brighter than Antares). Perhaps if I replaced it with a simple glow, without the rings?  nagual  design   14:27, 1 March 2016 (UTC)
 * I understand the reasoning. There's no right answer for me, but I'd like to see one without the rings, just keeping a spherical glow to suggest the excessive brightness. Tom Ruen (talk) 14:36, 1 March 2016 (UTC)
 * That seems like a good idea. Nagual, why do you want to remove your own image?  Its nice work.  Let's keep it. Jehochman Talk 14:41, 1 March 2016 (UTC)
 * ✅. As I explained above, I don't think artist's impressions are particularly encyclopedic at the best of times, and in this instance I think it might actually mislead readers, or reinforce their misconception, that Planet Nine is a bona fide new planet. People hear this 'exciting news story' from sources that are thin on science and come to Wikipedia for a summary of the 'facts'. Pictures say a lot, and sometimes they tell lies.  nagual  design   15:08, 1 March 2016 (UTC)
 * I'm happy! I'm not too concerned about misleading people or confusion of existence, as long as it is labeled clearly. I do believe in a little propaganda by pretty pictures. Carl Sagan's Cosmos inspired me with pretty pictures, and who knows what young kid will see the artwork, and say "Hey, I want to be an astronomer", in part because of a hypothetical planet, even if it doesn't exist, we know there's much more we'll be discovering in the exurbs of the solar system in the coming decades. Tom Ruen (talk) 18:54, 1 March 2016 (UTC)
 * I don't even think the "misleading" bit applies anymore. In the image, the planet is simply a spherical object, barely any colour and certainly no features. It's spherical, which obviously anything that could generate these gravitational perturbations would be. What else could be misleading or inspire misconceptions? I mean, the article does a pretty damn good job of bludgeoning us with the idea that this thing is hypothetical. — Huntster (t @ c) 05:56, 2 March 2016 (UTC)
 * I agree, and I !voted in the RfC to remove the image from the infobox. It's taken a while to get to the current image, but I think it is a good one. It's informative because it shows Neptune's orbit, giving a sense of distance. It's not very misleading because it depicts no features of Planet Nine except its sphericity. The article is clearly about a hypothesis, and the picture accurately, informatively, and responsibly depicts that hypothesis. A2soup (talk) 07:55, 2 March 2016 (UTC)

Existence
Do some scientists who are aware of this planet's hypothesis still believe that this planet doesn't exist?? Georgia guy (talk) 02:06, 1 March 2016 (UTC)
 * Some guys said it is like 50% or so it exists. Nergaal (talk) 02:44, 1 March 2016 (UTC)
 * Didn't Mike Brown himself say that he was (only) about 90% certain? Remember, this isn't the first hypothetical planet to have been posited, the rest of course having been disproved. Scientists don't generally make leaps of faith, they simply point to the evidence. In this case, that there's about a 1 in 15,000 chance of the orbits of a bunch of TNOs lining up the way they do by chance alone.  nagual  design   03:37, 1 March 2016 (UTC)
 * There is section Critics in Russian wiki: ru:Девятая планета. If you want I can translate it. --Vayvor (talk) 11:54, 1 March 2016 (UTC)


 * whatever criticism from English sources has already been included in the Inference section. Ethan Seigel doesn't provide any contradictory fact but he is merely skeptical. Regarding Jewett's claim - why only outer 6 - that is dealt with by Brown in their paper.
 * As such the situation has been, that, for almost 2 years, researchers have known there is something out there, maybe 1 planet or multiple small objects but before B&B, others couldn't come with any credible theory to explain the unusual data, which B&B have managed to do.
 * Of course the next step would be to find the planet, but without precise knowledge of its mass may not be possible to accurately determine its orbit.
 * If you need the opinion of a neutral observer Meg Schwamb would be the best for that. She is impressed/excited but also wonders if 6 objects is a sufficiently large dataset?
 * The LSST when it comes online in 2023 will clear all doubts on this topic once and for all. Have patience till then ... J mareeswaran (talk) 13:27, 1 March 2016 (UTC)
 * It's too long to wait till 2023... --Vayvor (talk) 09:20, 2 March 2016 (UTC)

Capture
A recent paper on arxiv investigating the probabilities of the capture or ejection Planet Nine. Agmartin (talk) 20:12, 2 March 2016 (UTC)
 * interesting. the entire conclusion is worth a read. and this comment in abstract

"Probabilities for producing the inferred Planet Nine orbit are significantly lower (<~5%)."
 * reminds me of Hal Levinson's 2% comment J mareeswaran (talk) 12:06, 3 March 2016 (UTC)
 * it occurs to me suggests a high mass star died not too far away and perhaps a planet from it might have wandered our way very early. Just a thought. --Smkolins (talk) 02:19, 5 March 2016 (UTC)
 * I just watched the Planetary Society's radio show (which had streaming video). Brown and Batygin seem to like idea that P9 was punted out there by Jupiter early in the solar system's history, and that nearby stars may have helped stabilize its orbit.  Jehochman Talk 04:46, 9 March 2016 (UTC)

High inclination objects
Can we include a diagram with the 5 "wing object" (high inclination, perpendicular orientation)? (second table at Planet_Nine) Tom Ruen (talk) 05:46, 5 March 2016 (UTC)
 * I'd suggest adding it to the animated gif, and then the Drac-type objects too if we can get them nailed down. :-) Alas I can see the idea but such graphics are beyond me.--Smkolins (talk) 13:21, 5 March 2016 (UTC)
 * For fun, I used InkScape to trace the ellipses of this JPG . The orbits were not labeled, so I just matched the colors for the types of bodies. (Like this BCC program talks about these 5 objects animation, as confirmational evidence because they were predicted to exist and confirmed.) Tom Ruen (talk) 07:59, 9 March 2016 (UTC)
 * Planet_nine_TNO_orbits.svg

New infobox image
Since most people agree that the artist's impression does not belong in the infobox, yet nobody seemed happy with the alternative (use one of the other images), I have made a new image that I hope will satisfy everybody as, I believe, it's eyecatching and encyclopedic.  nagual  design   06:09, 28 February 2016 (UTC)
 * Well, that is just fantastic! I've never seen a gif used in an infobox before - is there some reason for that? In any case, I would be happy with that gif in the infobox, and if it doesn't end up there, please put it somewhere else in the article. Great work! A2soup (talk) 06:56, 28 February 2016 (UTC)
 * GIFs used to have major issues with not animating in thumbnails. Its mostly been resolved, but still occasionally rears its ugly head. My only concern with this image is that it takes quite a long time (relatively speaking, in terms of reader patience) to run through the whole cycle. — Huntster (t @ c) 07:04, 28 February 2016 (UTC)
 * It's 30 seconds in total. Each of the pauses lasts for 5 seconds, except for the last one, which lasts for 10 seconds. I could make the pauses briefer, but you may end up with the opposite problem of having to wait for it to complete another cycle just so you can read one of the labels. This way, I hope, you only have to watch it once to take it all in.  nagual  design   07:16, 28 February 2016 (UTC)
 * ...Okay, I've shaved 5 seconds off by reducing the pauses to 4 seconds and 8 seconds, respectively. That still gives you slightly more than 12 seconds to read the labels on the TNOs. I guess that's enough.  nagual  design   08:24, 28 February 2016 (UTC)
 * reduce the pauses to 2.5 sec, and only 1 sec for the last pause. Nergaal (talk) 18:32, 28 February 2016 (UTC)
 * I experimented a little with different timings. Reducing the pauses further made the labels too fleeting. You'd have to be some kind of speed reader to make sense of all the TNOs in the amount of time you suggest. Sorry.  nagual  design   03:29, 1 March 2016 (UTC)
 * I like the animation, but still prefer the newest artistic image, especially with Neptune's orbit added, giving a sense of distance. Tom Ruen (talk) 23:14, 28 February 2016 (UTC)
 * The orbit of Neptune does make the artist's impression slightly more useful, but that may not be enough to change the opinions of those who took part in the RfC, myself included, though of course you're welcome to make your case there. IMO, the infobox should show this animation or one of the (static) orbital diagrams, or maybe some version of the P9 "treasure map" (yet to be uploaded to Commons, AFIAK). Regards,  nagual  design   03:29, 1 March 2016 (UTC)
 * "Treasure map"? I feel like I've missed something. Also Nagual, I feel like I only expressed criticism here...I think it is fantastically well made and that it should definitely be incorporated somehow (though I still think having an illustration in the infobox is the best course). — Huntster (t @ c) 04:20, 1 March 2016 (UTC)
 * Mike Brown posted a plot which they refer to as the "treasure map" on his blog. See the links provided at the bottom of Path in sky (above), including this lovely image. Smkolins may well be working on a version of it. Thank you for the kind words, though I actually found your critique more useful. You were right, 30 seconds was too long.  nagual  design   04:39, 1 March 2016 (UTC)
 * I can't exactly explain why, but I don't like question mark at the end of phrase "Planet Nine?". I think that it is not look nice. Does anyone have the same feelings? --Vayvor (talk) 05:26, 1 March 2016 (UTC)
 * Earlier versions I made of this diagram were based exactly on the 'best fit' shown in the Caltech video, with a smaller orbit and no question mark. Since then I have enlarged the orbit of P9 considerably, which is still within the realms of possibility (I think!), so now we are left with one possible orbit, though not the most likely, of a planet that might not exist, hence the dotted line and question mark. I'm willing to edit all of the images if enough people agree with you though. Luckily for you I omitted the question mark from the Russian language version as I don't know how to punctuate in Russian.   nagual  design   06:06, 1 March 2016 (UTC)
 * . I don't like the question mark for design reasons (I suppose that a dotted orbit is enough to show that this is a hypothetical object). But I agree that it will be nice to put Neptune orbit on the last image to make evident what trans-neptunian objects are. --Vayvor (talk) 08:06, 1 March 2016 (UTC)


 * Approve GIF in some form. That we haven't (much?) used GIFs in infoboxes in the past, does not deeply move me; perhaps it is time we did. More to the point, the discussion of artwork alternatives, even when a lot of work has gone into rival or collaborative efforts, suggests that there always will be enough justified objection to any product, to foster continued controversy, whereas the scope for continued objective improvement to a GIF seems to me more definite and constructive. I do however, have one strong opinion and urge those of us who are familiar with the field in general and the GIF in particular, not to speed it up. To the average reader just assimilating the concepts, let alone the process, is challenging, Now we are throwing repeated changes of scale at him or her, and I guarantee that most non-professionals will not be able to appreciate it at the speeds discussed. (Forget the pros reading the article; they don't need the pic; the Joe Blows and the ankle-biters are the ones who will need it and if you make it too fast they will not benefit in the slightest. 30 secs is already on the fast side, I reckon. As for adornments, I reckon only that anything non-informative should be omitted as noise. JonRichfield (talk) 20:05, 5 March 2016 (UTC)
 * I completely agree with everything you've said here, Jon. Having once designed websites for around 10 years I appreciate the concept of not stuffing too much meat into a sandwich. I think it's enough to show the orbits (sans positions) of the 8 known planets, the possible orbit of the 9th, as well as the orbits of the 6 TNOs on which the hypothesis is based.  nagual  design   12:21, 6 March 2016 (UTC)


 * This moving image is a poor idea for the infobox. That image should one where the user can identify what it's showing within a split second.  It is unreasonable as a first introduction to the topic for the user to have to sit through X seconds of GIF animation to get the point.  This is a useful image, but it should be placed lower in the article after the user has already delved into the topic. Jehochman Talk 03:07, 6 March 2016 (UTC)
 * The notion of 'split second identification' is not part of any guideline that I can find. Nor do I think it's unreasonable for the reader to watch an animation play out. It has great EV, in my opinion. Certainly more than the artist's impression.  nagual  design   12:21, 6 March 2016 (UTC)
 * If we had perfect visual data covering the concept, certainly such a sketchy, stylised, and speculative representation would not be a rational first choice, but the artistic impressions we have seen so far lack split-second merits as well as lacking almost any other merit apart from artistic satisfaction, which is debatable and unlikely to improve the article or its comprehension in any predictably substantial way, to put it kindly. So those works do not get a look-in IMO, even versions that do happen to include bona fide stellar backgrounds. Willy Ley did more impressive work, as I remember from childhood, and that was well before Sputnik. We lack his excuses, and anyway, he wasn't illustrating encyclopaedias. Note for example that the current artistic image has a pretty fat caption; pretty reasonable as it happens, but hardly split-second. I do not argue that no better visual, whether animated or not, could be implemented, nor that this version is beyond improvement, but so far I have seen none myself. Given a caption no larger than the current one, the GIF should be reasonably understandable, and it it should give an perspective of scale far superior to anything else I have seen in this discussion. About the main improvement that I could suggest just at present, would be another zoom-out to include Alpha Centauri and possibly some belts (for yet more perspective), but it is best to be cautious for the reasons that Nagualdesign gave. IMO, the GIF works as it stands, is not vacuous, and everything else I have seen fails such criteria. JonRichfield (talk) 15:48, 11 March 2016 (UTC)


 * I've changed the GIF's display syntax to use relative sizing to honor user preferences (see MOS:IMGSIZE) and think this is a far more informative infobox image than the subjects of the discussions immediately above. Are there (apart from speed of loading) any other technical arguments against its use? Is it technically possible to display a faster loading static image first, followed by the animated GIF after it has loaded? BushelCandle (talk) 00:11, 8 March 2016 (UTC)


 * I like the scaled orbits animation, good for the article, just not for the infobox though. Yes best too if activated by the reader.  The final view should be the first view waiting for the reader to activate.  Aoziwe (talk) 20:29, 11 March 2016 (UTC)
 * If we all are talking about Planet Nine animation.gif then:
 * * I have just checked on the current artistic impression again (after quite a hiatus), and in spite of the fact that it obviously is the product of a lot of work and talent, even the labelled version conveys practically no relevant information to the reader; it is an irrelevant star field with an arbitrarily placed and scaled circular opaque hole; and what is worse, I cannot imagine any way to improve any representation of that type; we simply lack any better information for the foreseeable near future.
 * * I have had another look at the gif as labelled and with the current timing. It already is pretty good; easy to follow and re-follow until the reader has the mental picture, and s/he can follow and re-visit the labels ad lib. If the static view of the total final image could be pinned onto the unactivated GIF as Aoziwe suggests, with a visible instruction to click for animation, that might be nice, though actually it would be OK as it stands if that option is not practical.
 * * However, one good point about starting with a static image if possible, would be that readers would not be distracted by movement while trying to read the main text. But if that is not avoidable, then IMO better put the GIF in the box than in the text; it is less obtrusive there than when trying to concentrate on the main text.
 * * BTW, is omission of mention of Pluto deliberate, or have I just missed it?
 * * I urge that, though we do not yet have perfection, this version is good, and constructively useful enough for the infobox now. Its imperfections reflect limitations to the information currently available, which places severe restrictions on proposals of any alternatives as rivals represented as being more useful or FTM, more striking; the impression of scale is quite haunting. No matter how clever any alternative might be, it cannot convey information that is not available for display. It is time to put the GIF into the infobox and stop about-it-and-abouting. If anyone can improve on it, then fine, but there is nothing stopping such improvements or replacements being added later. Just now this is the current best and most useful candidate and belongs on the page. JonRichfield (talk) 05:35, 12 March 2016 (UTC)

Planetary Radio podcast
This was mentioned above. Recording now available. http://www.scpr.org/events/2016/03/08/1874/planetary-radio-live-all-these-worlds-planet-9-and/

Jehochman Talk 07:50, 13 March 2016 (UTC)


 * They discuss the artistic conception by Robert Hurt 25:05 Mike says "He even added a bit of lightning on the dark side which is pure speculation but it may well, if its a gas giant like this, it probably does have lightning going on like this, like if you were on one of its moons, if it had one. ... It's actually right in front of the milky way galaxy, he does them geometrically accurate so you're seeing a real star field with the real star brightness, the real sun.. You see a little bit of glare around the sun, some of it would be zodiacal dust around the sun. I think that's probably what he's showing there. (or lens flare from the spacecraft around planet nine)" Tom Ruen (talk) 08:28, 13 March 2016 (UTC)

Star chart
Jason Hingley has a page with plots of Planet Nine's possible orbits against the stars. The background is from the Tycho 2 catalogue, if someone with knowledge of possible copyright issues wishes to email him his contact info is on his main page Agmartin (talk) 18:28, 16 March 2016 (UTC)
 * I agree something like this would be better than my single path example in Orion File:Planet nine path in orion2.png. Tom Ruen (talk) 21:17, 16 March 2016 (UTC)
 * Agree something like this would help a lot. And once the pattern is worked out an animated gif or something could rotate the view and note inclusion/exclusion zones from other papers (and so noted.) But my hat's off to who can pull it off. --Smkolins (talk) 22:12, 17 March 2016 (UTC)

Semi-major axis
New on arxiv, a semi-major axis of 665 AU places the most distant objects in N/2 and N/1 resonances. Coralling a distant planet with extreme resonant Kuiper belt objects This is an interesting coincidence but it should be remembered that in Batygin and Brown the objects also spent time in the weaker resonances. Agmartin (talk) 17:56, 8 March 2016 (UTC)
 * they have given restrictions on Mass, inclination, eccentricity & probable location. would be interesting to see what B&B think of this? J mareeswaran (talk) 18:21, 8 March 2016 (UTC)


 * "We conclude that an HP orbit plane with inclination near i ≈ 48◦ and longitude of ascending node near Ω ≈ −5◦ allows all four resonant eKBOs to be in proximity of the periodic orbits of the third kind."
 * "We conclude that ∼ 10M⊕ is the minimum mass necessary to maintain periodic orbits of the third kind for the four eKBOs."
 * "We determined exclusion zones of the current location of the planet in its orbital path (Fig. 5)" (which is a complicated exclusion/inclusion map, a series of 8 ranges of longitude, one of them very small but overall knock out half the orbit - anyone check if any of these align with the Saturn-perihelion inclusion zones?) --Smkolins (talk) 19:04, 8 March 2016 (UTC)
 * The Saturn-perihelion precession zone favored ~120° from perihelion (which is itself vague so far but roughly in the direction of Ophiuchus.) --Smkolins (talk) 19:10, 8 March 2016 (UTC)
 * If i'm reading these charts right the saturn-p-p inclusion zone almost overlaps with the mean-resonance zone of Fig 5 near the right and left edges, ie near >340° and <20° longitude which read to be roughly the Eridanus/Cetus region. See --Smkolins (talk) 19:20, 8 March 2016 (UTC)
 * I agree. The Cassini "green zone" is between RA 350 and 10, in the direction of Sculptor (next to Cetus).  It's curious that the resonance model also likes that zone.  Jehochman Talk 04:48, 9 March 2016 (UTC)
 * There are two possible inclinations mentioned in the new paper, one appears to be similar to the one described in B&B, the other involving a 'periodic orbit of the third kind' is significantly larger. They don't mention whether the higher inclination orbit would produce the objects with perpendicular orbits mentioned in B&B. Agmartin (talk) 19:46, 8 March 2016 (UTC)
 * I don't know if they are describing two orbits or a range. I'm also not sure how the differing points of results are set against the other results. But sure interesting. I recall comments about the mutuality of periodicity being speculated upon in early chatter on this talk page. --Smkolins (talk) 21:06, 8 March 2016 (UTC)
 * Emily Lakdawalla has an article discussing the paper. She mentions something I missed, the low inclination orbit has a max eccentricity of 0.18. This appears to have something to do with aligning the orbits in a rotating frame of reference. I suspect this limit only applies if the objects are assumed to always stay in the same resonance. Agmartin (talk) 02:20, 9 March 2016 (UTC)
 * Looks like she missed the Saturn-periihelion-precession related paper. And alas I missed the podcast meeting. I don't see a link to rebroadcasting….--Smkolins (talk) 09:27, 9 March 2016 (UTC)
 * Also I see I keep using the Saturn-perihelion-precession terminology - the paper is only about "residuals" in fine positioning (which I read to be in the hundreds of meters distances) of Saturn in its orbit. So trying to purge the p-p terminology proceeding. (sigh) --Smkolins (talk) 09:55, 9 March 2016 (UTC)
 * It would be great if someone could specifically align with the inclusions/exclusion zones of the other two papers rather than having to guess and stretch measurements. I'm sure it could be done (noting the Saturn-residuals restrictions depend on an uncertain perihelion location, perhaps a 20° margin?)--Smkolins (talk) 10:08, 9 March 2016 (UTC)
 * While this paper certainly has a lot of promise, it hasn't cleared peer review yet. I'm not sure we should include it yet.  Reliable people seem to think it is good work, but could there be an error?  Brown and Batygin like 30 degree inclination.  This paper proposes 18 degrees or 48 degrees.  Is there enough margin of error for them to reconcile?  What about B&B proposing eccentricity of 0.6 while this paper says the eccentricity is much smaller?  Do we report this now with caveats, or wait a little bit to see if there's a revision, retraction or further explanations? B&B ran extensive supercomputer simulations that show what happens to the objects as they orbit.  This paper came at the problem from a different direction; theoretical math.  Did the theoretical approach factor in the gravity of Neptune, or just P9 and the 4 small objects?  When two reliable sources disagree, it would be nice to get an explanation of why they might disagree.  Perhaps that will be forthcoming. Jehochman Talk 04:52, 9 March 2016 (UTC)
 * Brown & Batygin’s modelling investigated 30º increments of inclination i′ from 0º up to 180º (§ 5.1 of their paper describes the planar case; § 5.2 describes the inclined cases). Malhotra et al.’s values of 18º and 48º fall between three of B & B’s values, so that it would be best if B & B could provide new modelling at 15º increments across the same range (or just the i′ = 15º and i′ = 45º cases). Malhotra et al.’s low inclination case (closest to the B & B coplanar modelling) doesn’t seem to map well to B & B, because as Emily Lakdawalla noted at the Planetary Society blog eccentricity e′ is limited to a maximum of ≲ 0.18, whereas in B & B the orbital clustering imposed a minimum e′ ≳ 0.4. This is a seeming incompatibility that would require further modelling to resolve. In Malhotra’s higher inclination case of i′ ~ 48º, there is no such hard constraint on e′ that is incompatible with B & B’s projected value of e′ ~ 0.5 – 0.8 (later refined to 0.6). Philip User Talk Email 06:23, 9 March 2016 (UTC)
 * A good summary from my reading too. The only thing I'd add is that Malhotra et al carefully refined the orbits and error margins and I'm not sure I saw B&B do the same. --Smkolins (talk) 10:12, 9 March 2016 (UTC)
 * I think it would be interesting to see B&B run their model at 48 degrees inclination, and also the Cassini model at 48 degrees inclination to see what that yields. Between Cassini and Malhotra the locations remaining to search should be rather compact.  Jehochman Talk 15:19, 9 March 2016 (UTC)
 * A list of the objects used in Malhotra et al (those with perihelia > 40 and a > 150 AU) Sedna (90377) q=76.045 a=507, 2010 GB174 q=48.719 a=371, 2004 VN112 q=47.327 a=320, 2012 VP113 q=80.290 a=262, (148209) aka 2000 CR105 q=44.286 a=228, 2013 GP13 q=41.117 a=153. I believe 5 of these (but not 2013 GP13) are among the 6 on stable orbits noted in B & B. Agmartin (talk) 21:39, 9 March 2016 (UTC)


 * It makes sense to include this paper, since it specifically references the Planet Nine hypothesis and is not just some alternate attempt to postulate some planet far from the Sun. Wnt (talk) 21:29, 12 March 2016 (UTC)
 * I agree but where, as a new section under Case for a new planet or as an alternate hypothesis? One question I have is whether the objects with perpendicular orbits would be produced by the low eccentricity orbit proposed by Malhotra, Volk and Wang. Agmartin (talk) 22:44, 12 March 2016 (UTC)
 * While listening to the recording of Planetary Radio, (thanks Jehochman) I noted that one of them pointed out that the alignment of perihelia only occurs for an eccentric orbit. Though they do describe how the alignments of the orbits can aid in pinpointing Planet Nine's location, I don't recall the alignment of perihelia toward one side of the Solar System being mentioned in Malhotra etal. Agmartin (talk) 20:58, 13 March 2016 (UTC)
 * From the first paragraph of section 2.3 'Given that Sedna is presently near its perihelion, λ ≈ ω bar, the planet can be in proximity to one of three longitudes: 60° or 180° or 300° from  Sedna's  longitude  of  perihelion, ω bar.' I believe this means that the low eccentricity orbit does not require that the orbits of the objects being aligned in one direction. Agmartin (talk) 16:58, 14 March 2016 (UTC)
 * good catch. that means, the eccentricity/elongation of detached objects can only be explained by a high eccentric perturber and that automatically rules out the low-inclination orbit (as per B&B's simulations). I also remember Brown commenting the mean-motion resonances could be complex ratios such as 22/15 etc and hopefully another paper is coming from them on this :) J mareeswaran (talk) 19:05, 14 March 2016 (UTC)

p.s. Mike Brown said there was another paper coming, but not when! Tom Ruen (talk) 20:48, 14 March 2016 (UTC)
 * Any day now


 * New paper: http://web.gps.caltech.edu/~mbrown/papers/ps/findp9.pdf Jehochman Talk 03:22, 18 March 2016 (UTC)

Paper: Corralling a distant planet with extreme resonant Kuiper belt objects
A new paper! , Submitted on 7 Mar 2016, Renu Malhotra, Kathryn Volk, Xianyu Wang
 * The four longest period Kuiper belt objects have orbital periods close to small integer ratios with each other. A hypothetical planet with orbital period ∼17,117 years, semimajor axis ∼665 AU, would have N/1 and N/2 period ratios with these four objects. The orbital geometries and dynamics of resonant orbits constrain the orbital plane, the orbital eccentricity and the mass of such a planet, as well as its current location in its orbital path.

Mentioned here: Scientists are getting closer to discovering if there's actually a mysterious 'Planet 9'
 * Their analysis also offered suggestions as to what kind of resonance the planet has with the KBOs in question. Whereas Sedna’s orbital period would have a 3:2 resonance with the planet, 2010 GB174 would be in a 5:2 resonance, 2004 VN112 in a 3:1, 2004 VP113 in 4:1, and 2013 GP136 in 9:1. These sort of resonances are simply not likely without the presence of a larger planet.

I added to the table here, first two are new ones, with 150<a<250 AU.

These two were excluded with q=36.

Mike Brown's comment
I asked about Malhotra and received this reply with permission to quote:

"The difficulty is that Malhotra is not talking about Planet Nine. She is proposing a different planet with different effects. Specifically, she is only trying to explain an assumed resonant structure of the several most distant objects. She makes no attempt to explain the physical alignment of the orbits nor does her planet align orbits. Which is why she gets a different planet.

If you believe that the orbital alignment is real, however, her explanation cannot be correct. But if there is no orbital alignment maybe it is and there is a big planet in a circular orbit out there.

We have a paper coming out this week that will help, I think."

- Mike Brown

I'm not sure where we go from here. Maybe we play it safe and wait for the new paper to see what it says. Obviously we can't use my correspondence as a source for the article, but as editors we can try to better understand the topic and avoid propagating errors. Jehochman Talk 04:29, 16 March 2016 (UTC)
 * How about this as an addition under alternate hypotheses 'Renu Malhotra, Kathryn Volk, Xianyu Wang have proposed that the four detached objects with the longest orbital periods, those with perihelia beyond 40 AU and semi-major axes greater than 250 AU, are in N:1 or N:2 mean motion resonances with a hypothetical planet. The dynamics of these objects are used to identify possible orbits and positions for a hypothetical planet and estimate its mass. Unlike Batygin and Brown paper their work does not specify that the most distant detached objects would be have orbits anti-aligned with the massive planet.' Agmartin (talk) 19:05, 16 March 2016 (UTC)


 * Given this paper is using a slightly different set of TNO, I'm okay with either a special section, or keeping this paper out of the article UNLESS it is publicly referenced by other astronomers. Tom Ruen (talk) 02:06, 17 March 2016 (UTC)

It's probably a good idea to mention the paper and contrast how its predictions are different from B&B. What we must not do is try to fuse them together. There is no evidence that the two theories are compatible, and above we have an expert opinion (unpublished) that they aren't. Jehochman Talk 02:21, 17 March 2016 (UTC)

I see a paragraph commentary on page 8 of the new paper, OBSERVATIONAL CONSTRAINTS ON THE ORBIT AND LOCATION OF PLANET NINE IN THE OUTER SOLAR SYSTEM, Michael E. Brown & Konstantin Batygin, Draft version March 17, 2016: "A recent paper (Malhotra et al. 2016) makes no attempt to explain spatial alignments, but instead attempts to simplistically look for mean-motion commensurabilities in the distant KBOs, in hopes of being able to constrain both a9 and the location of Planet Nine within its orbit.

Specifically they assume that the four most distant KBOs are in N:1 and N:2 resonances, and examine the implications for Planet Nine. Such an approach could, in principle, work in the circular restricted three-body problem, but, as shown in (Batygin & Brown 2016), highly elliptical orbits are required to explain the spatial confinement of the orbits, and no specific resonances dominate the disturbing function in this elliptical problem.

Indeed, no particular preference for type of critical angle or even resonance order can be identified in the dynamical simulations shown here. Rather, the crossing orbits evolve chaotically but maintain long term stability by residing on a interconnected web of phaseprotected mean motion resonances.

The assumption of simple low order resonance is thus unlikely to be justified. Not surprisingly, the Planet Nine orbits produced by these assumptions do not produce the spatial confinements of the KBOs that are observed. Thus, it appears that no useful constraint on the orbit or position can be drawn from this method."


 * Well that is a clear statement that they perceive a difference. However it seems odd to me to that there is a phase protected relationship that survives over massive time while at the same time the phases (resonance order/critical angle) cannot lock down the location of planet nine.--Smkolins (talk) 11:12, 18 March 2016 (UTC)
 * I think the difficulty in locking down the location is due to possible high order resonances. An object on a first order resonance like Pluto with Neptune is passed at one location in its orbit, when it is near aphelion; and it reaches perihelion at two locations relative to Neptune. If you know Pluto is at perihelion at a certain time you can two locations where Neptune should be, (technically a range of locations if the libration of its orbit is included). For an object on a higher order resonance the perihelion can be in many locations relative the primary for example object in a 10/7 resonance with Neptune the perihelion will occur in seven locations relative to Neptune. Now consider if you didn't know whether the object was in a 10/7 or 14/10, then you would have 7 locations from the first and 10 from the second, that in combination cover most of Neptune's orbit, although not all. And that is the case for a circular orbit, add an unknown semi-major axis and eccentricity and the possibilities grow. They probably can project orbits ahead and backward and say planet nine couldn't be within some distance of this point at that time but with only a small number of objects that still will leave many potential orbits and locations. Agmartin (talk) 20:16, 18 March 2016 (UTC)

Severe overlinking
I started to see repeated linking of some of the technical terms in the article and started to do a little clean up and then noticed how really bad the problem is in the article. the MOS very clearly states in the section WP:REPEATLINK that Generally, a link should appear only once in an article, but if helpful for readers, a link may be repeated in infoboxes, tables, image captions, footnotes, hatnotes, and at the first occurrence after the lead.. I deleted about a half dozen repeated links to semi-major axis when I started noticing the same problem with many of the terms. The phrase appears 15 times in the article spelled out and abbreviated in tables several times. I noticed that almost all of the column headers in the tables are wiki-linked and I see that this is allowed as an exception to the general rule. I actually went back and restored the two that I removed.

There are also many links that may violate the rule about avoiding linking Unless a term is particularly relevant to the context in the article so I am questioning whether terms like aperture and field of view should be linked as this is not an article about telescopes so therefore they are not particularly relevant. I am requesting that some other editors step in and help clean this major overlinking problem in the article. I won't be able to get back to it for several days.  Nyth 63  02:23, 17 March 2016 (UTC)
 * Firstly, the rule against overlinking is not a life-or-death matter like one of the five pillars; it is a contentious matter of aesthetic preference. Secondly, the reason for linking at all is to assist readers who encounter terms that they do not recognize in context, and might not know how to search for in the proper context. It also is completely acceptable to repeat the link on pages separated far enough for the link to appear only once per screen. Linking is not about whether the article is about the linked terms, but about whether the reader needs help; the very fact that this article is NOT about telescopes is precisely why we do prefer to link to the articles that deal specifically with the concepts in question rather than explain them in this article. Note too, that "aperture" and "field of view" are not terms limited to concepts concerning telescopes at all, so to avoid linking them as often as may be helpful makes sense. A layman might not have any idea what they are or why they are important, and not realise that there are articles that deal with them; after all, they are common English words; why should they have articles? By linking them you alert the layman to the fact that the term is technical, and that if he is not sure of its technical meaning, he should click on the link and check it out. Unnecessary removal of reader aids is not a service, but reduction of the value of the service. JonRichfield (talk) 08:25, 18 March 2016 (UTC)
 * It's a disregard and disrespect for the Manual of Style and Wikipedia policy that cause contention. Arguing that it can be disregarded because it is not one of the five pillars is a logical fallacy. Many hours were spent discussing and creating the MOS including consideration for aesthetic preference. An interpretation to mean once per screen is vague and not mentioned in the MOS. There is a huge difference between when I edit on my dual-screen system on a monitor in portrait mode verses somebody trying to read the article on a smartphone. I would agree that for lengthy articles, once per major section may be acceptable but that is still a interpretation. Surely you would agree that liking a term three times in the same section would be excessive? There is a reason that links to terms not specifically related to the subject of the article is discouraged.  The reason that it was found that almost ALL of these links are not followed and were therefore not actually helping anyone.  For example, could you please tell me how linking to northern hemisphere is justified in this article?  It is not directly related to subject and you have to assume at least a minimal level of intelligence and subject knowledge, especially with the generally fairly high level of astronomy and orbital mechanics presented in the article and the resulting filtered target audience. This article most definitely not very accessible to a layman. It seems to me that someone who does not already know what the northern hemisphere, aperture, or field of view is, will not likely be trying to wade through and read this article.  As far arguing that they should be linked just because they have their own article is not logical as the most common word in English has an article and you would not link to that would you?. In general, the MOS clearly state that wikilinking should be kept to a MINIMUM and should only be practiced when necessary.  The current state of this article is a perfect example of what the MOS is trying to prevent.  Nyth  63  13:01, 20 March 2016 (UTC)
 * I find that the MOS does not, in general, garner or warrant a whole lot of regard or respect. Ignore All Rules, in all things, if it will improve the useability of the article. — Huntster (t @ c) 02:41, 21 March 2016 (UTC)
 * I also agree that linking to aperture and field of view is useful as it will take a "wide field telescope" to find P9. My only question is should aperture be changed to Primary mirror. -- Kheider (talk) 02:53, 21 March 2016 (UTC)
 * As a good contrarian, I'll offer a vote for overlinking as mostly harmless. I really hate it when I see a technical term and have to visually scan through many screens to try to find a link to it, so my minimum overlink criterion is to stop at first usage per paragraph, and if this is offensive, then rule-bound people can quote MOS all they like, and have their way if they want to waste their lives systematically unlinking things until else someone gets frustrated and adds it back. Tom Ruen (talk) 03:04, 21 March 2016 (UTC)

Paper: Finding Planet Nine: a Monte Carlo approach
New paper on arxiv link from conclusion "If Planet Nine is at aphelion, it is most likely moving within α∈(8,9)h and δ∈(5,7)°. Another solution, α∈(3.5,4.5)h and δ∈(5,7)°, is less probable. Both locations are compatible with an apsidal antialignment scenario."


 * Who is this author? Are they reliable? Jehochman Talk 15:24, 23 March 2016 (UTC)


 * Interestingly here's a 1/16/2015(!) article by the author Trans-Neptunian study suggests Solar System contains more planets, a full year before B&B's paper. Tom Ruen (talk) 16:43, 23 March 2016 (UTC)
 * Yes, B&B's paper mentions them on the first page of the Jan 20 paper. Their 2014 paper is ref-37 in this article. Tom Ruen (talk) 17:49, 23 March 2016 (UTC)
 * Recent simulations (de la Fuente Marcos & de la Fuente Marcos 2014) confirmed this lack of bias in the observational data. The clustering in &omega; therefore appears to be real. ... However, de la Fuente Marcos & de la Fuente Marcos (2014) note that the existence of librating trajectories around &omega; = 0 requires the ratio of the object to perturber semi-major axis to be nearly unity.