Talk:Planet Nine/Archive 2

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All known minor planets with perihelion greater than 30 AU and a semi-major axis greater than 250 AU currently support the Planet Nine hypothesis

These six ETNOs are the exact same list that Brown is talking about. This a large part of the reason the Super-Earth "Planet Nine" hypothesis is so strong. The question will become how many future discoveries of minor planets with "q>30 and a>250" will continue to support the idea? I do not see a reason not to mention this in the article. -- Kheider (talk) 01:57, 27 January 2016 (UTC)

First, to the point you are trying to make about the ETNOs - see this paragraph

Trujillo and Shepherd analyzed the orbits of trans-Neptunian objects (TNOs), those with perihelion greater than 30 AU and a semi-major axis greater than 150 AU, and found they had a cluster of orbital characteristics, particularly the argument of perihelion, which describes orbits oriented in space.[4][3] They proposed a "single body of 2–15 Earth masses in a circular low inclination orbit between 200 AU and 300 AU" to explain the pattern. It was not the only way to create the clustering of the orbital orientations. Brown and Batygin then analyzed six extreme trans-Neptunian objects in a stable configuration of orbits mostly outside the Kuiper belt (namely Sedna, 2012 VP113, 2007 TG422, 2004 VN112, 2013 RF98, 2010 GB174),[3] A closer look at the data showed that these six objects trace out elliptical orbits that point into approximately the same direction in physical space, and lie in approximately the same plane.[19][20] They found that this would only occur with 0.007% probability by chance alone.[21]

Second note that the "citation" of minorplanetcent.net is not a citation at all - it's a list of such bodies and says nothing whatsoever about B&B's analysis saying they are all supporting the prediction of a planet. To site it you need an actual citation of the statement. The gist of it is in the existing paragraph but the exact phrasing needs its own real citation.--Smkolins (talk) 02:19, 27 January 2016 (UTC)
So you are saying you can not look at the list of 6 TNOs in this article and figure out that the statement is true? ETNOs have "q>30 and a>150" (of which there are 14 with an observation arc greater than 1 yr) and are a small subset of the 1792 known TNOs. There are ONLY 6 TNOs KNOWN that have "q>30 and a>250" and they are all detailed in Brown's paper.-- Kheider (talk) 02:33, 27 January 2016 (UTC)
It looks important to me. Its different claim to say "6 of 10,000 objects have an unsual alignment" versus "6 of 6 object"! Tom Ruen (talk) 02:58, 27 January 2016 (UTC)
I have changed the wording to: "There are only six known minor planets with perihelion greater than 30 AU and a semi-major axis greater than 250 AU." The reference supports that statement perfectly. -- Kheider (talk) 08:20, 27 January 2016 (UTC)
one of the linked refs had a contra question by another scientist. "We know that 6 extreme TNOs support Planet Nine thesis. But what about the other 100 or so inner objects? Are they in alignment with a prediction of this planet's orbit or against that?"
This requires further analysis and probably other researchers are working on this topic right now. It can also be considered as a sort of peer-review of B&B's modelJ mareeswaran (talk) 11:49, 27 January 2016 (UTC)
The MPC citation obviously does not support saying that all six support Planet Nine's existence, but I have seen that exact claim in a source. So far, I haven't managed to recover it, but it should be out there. --JorisvS (talk) 14:22, 27 January 2016 (UTC)
The blog "findplanetnine" says, "Planet Nine has an orbit which is anti-aligned with respect to the 6 most distant eccentric Kuiper belt objects" -- Kheider (talk) 16:24, 28 January 2016 (UTC)
That's why I put the >150AU statement in originally - the other paper included them originally and so had a farther reach. They entertained multiple causes including a planet out there. B&B narrowed the focus to only the extreme TNOs and inner Oort objects. Right now we can't more about the other objects until someone publishes. One of the other frequent researchers on this (I(something) is looking at Saturn and believes he'll eventually be able to tease out an affect because of the long history we have on Saturn's position and the Cassini craft helping to pin point more specifically - but as of now he can't say he's found an affect. --Smkolins (talk) 17:58, 27 January 2016 (UTC)

V774104

And per comment above we now have:

and in November 2015 the farthest object, of the solar system, V774104 was discovered but its orbital details are still awaiting to be calculated. the following links discuss this object and possible theories

  • Sheppard is training Subaru on swaths of the sky an average of 15° away from the ecliptic, the better to find other weird objects
  • "There's several different theories about how these distant objects could have got out there on these eccentric orbits. And all these different theories predict different orbital distribution and orbital population. So if we can find 10 or so of these objects, then we can start determining which theories of the formation of these objects are correct."
  • V774104 is so distant that it will take another year of study to determine its orbit There's no consensus on why they're out there; possible causes run the gamut from gravitational stirring of the even more distant Oort Cloud by a close-passing star to the presence of an undiscovered massive planet far beyond the orbit of Neptune. Or they might be the first-found members of the inner Oort Cloud…

So now it is INCORRECT to say all >150AU support the prediction. --Smkolins (talk) 18:03, 27 January 2016 (UTC)

But it is CORRECT (and fairly obvious) to say all "q>30 and a>250" currently support the prediction. -- Kheider (talk) 18:21, 27 January 2016 (UTC)
No - that's my point about V774104 - while it's orbit isn't well characterized it could but doesn't have to support the prediction (I found a source saying it is currently in the direction of Pieces which fits if it is near perihelion. But it's semi-major access could be >250 as it is the farthest known object in the solar system. --Smkolins (talk) 18:41, 27 January 2016 (UTC) (orbital placement image at [2]) --Smkolins (talk) 18:42, 27 January 2016 (UTC)
You'd have to say something like - Of the objects in the solar system with known characteristics as of January 2016, and this excludes V774104 at present, all objects q>/a> etc etc support the prediction and objects as far in as a>150AU also can support the prediction. Or something like that. But's getting more and more cumbersome to make a bold claim. --Smkolins (talk) 18:46, 27 January 2016 (UTC)
Your assumptions about an unpublished orbit are meaningless. -- Kheider (talk) 21:12, 27 January 2016 (UTC)
I'm not making any assumptions. That's what I'm trying to point out. And can we work on the tone here? We are all trying to make the article actually better. --Smkolins (talk) 22:12, 27 January 2016 (UTC)
V774104 is an object with no published orbital parameters. All we publicly know is that V774104 was discovered roughly 103AU from the Sun and it may be a sednoid. Did V774104 come to perihelion 50 years ago, now, or will it 50 years from now? Sheppard wanted a longer observation arc to better constrain the orbit before going public with his data. -- Kheider (talk) 22:25, 27 January 2016 (UTC)
Granted. In which case it may be very relevant some time. Undoubtedly, if it follows the pattern or not matters. And it is farther out than Sedna and VP113 by a good measure at best guess on distance right now. It would be an improvement that the statement have good qualifiers - not just the perihelion and semi-major access but that as known so far and it could just as easily note an important distant body in the mix. --Smkolins (talk) 22:34, 27 January 2016 (UTC)
Actually not all bodies are expected to follow the pattern. The fact all 6 known/published ones do is interesting. Talking about unpublished orbits and future undiscovered ETNOs is meaningless to the statement I added to the article. -- Kheider (talk) 22:42, 27 January 2016 (UTC)
This is my understanding, somebody can correct me if I am wrong. Every object found that is close to the prediction strengthens the hypothesis. If even a single object found which doesn't satisfy the prediction then it could result in complete failure of the hypothesis. J mareeswaran (talk) 11:40, 28 January 2016 (UTC)
"One caveat: our computer simulations do not predict that 100% of the most distant objects will be clustered." -- Kheider (talk) 19:33, 28 January 2016 (UTC)

I tweaked the wording from "only known minor planets with perihelia" to "only minor planets known to have perihelia", I hope this fixes the V774104 issue. --Ørjan (talk) 03:30, 28 January 2016 (UTC)

I fail to see why objects not submitted to the Minor Planet Center are even an issue. Every object submitted to the MPC has a nominal solution to perihelion and semi-major axis. V774104 is ~103AU from the Sun and could be ±100 years from perihelion. -- Kheider (talk) 08:08, 28 January 2016 (UTC)
My point is that the original language stated the case as a kind of triumphant absolute. I preferred a more cautious approach to the facts.--Smkolins (talk) 11:04, 28 January 2016 (UTC)
V774104 was announced with a pathetic 2 week observation arc and no orbital elements. TNOs with a 28 day observation arc can have large uncertainties in semi-major axis. -- Kheider (talk) 22:00, 28 January 2016 (UTC)
Why do you even "go to" "pathetic"? There is a strong judgmental attitude in language like that. Things don't have to be black and white. As the quote on whether one object not following the pattern would break the prediction. This is why I wanted qualified language in the sentence. One qualification is that of "so far" as in "as of January 2016 all objects" such and so etc. --Smkolins (talk) 00:22, 29 January 2016 (UTC)
When dealing with ETNOs an observation arc of 2 weeks in nothing more than a press release. -- Kheider (talk) 15:09, 29 January 2016 (UTC)

Thelisto and Telisto

No offence to Lorenzo Iorio, but neither of these words has any meaningful Google hits. Can someone insert some sort of meaning or translation of them into the article? 2601:47:4201:C8FF:858A:A350:D148:6857 (talk) 03:58, 29 January 2016 (UTC)

Are you asking for explanation of Iorio's research or why he chose Telisto? look up Telesto for what is Telisto/Telesto/Thelisto J mareeswaran (talk) 08:53, 29 January 2016 (UTC)
Dear Wikipedia users, thank you for your interest. As far as the hypothetical planet is concerned, the correct name I proposed for it is Telisto; Thelisto is just a typo. Indeed, it comes from the adjective τήλιστος (tḗlistos), meaning farthest, most remote. Instead, the name of one of the moons of Saturn is Telesto, coming from the name of the deity Τελεστώ (Telestṓ). Best regards. --Lorenzo Iorio (talk) 15:32, 29 January 2016 (UTC)
Thanks for the clarification. I already added a note. will update it with this explanation J mareeswaran (talk) 16:20, 29 January 2016 (UTC)

Simulation

Could someone please look at the first paragraph under the section titled Simulation? I have a degree in engineering and even I find in rather dense. Most of the terms as used here are meaningless without the proper context and there is probably not enough information to reconstruct the simulation. I seems rather unencyclopedic in that it really does nothing to clarify or clearly explain anything for the average reader. I understand that there are many examples of higher math in Wikipedia that the average ready may not understand, but at least the attempt is made that if someone with the background were to try to follow it, there is complete enough information to reach a conclusion. This certainly does not do that. This paragraph should be either summarized in a couple of short sentences or else deleted completely. It also appears that it may be a copy/paste from somewhere which would make it a potential copyvio. Nyth63 14:09, 28 January 2016 (UTC)

the bottom of "The case for Planet Nine" section gives the english description you are looking for, I beleive. I am fine with both being present in this article. J mareeswaran (talk) 14:19, 28 January 2016 (UTC)
Since there is no section titled "The case for Planet Nine", I will assume that you mean the section titled Case for a new planet. Thank for pointing it out as it appears that we have two redundant, and at the same time, contradictory paragraphs. The numbers quoted in both paragraphs appear to be somewhat contradictory and should be reviewed for consistency and probably consolidated. All the more reason to dumb it down a little. Nyth63 00:28, 29 January 2016 (UTC)
That's a little better but I wonder if a short table would be a better presentation of a list of variable and parameters like this. Rather hard to read in a long, strung out sentence like this. Nyth63 14:19, 29 January 2016 (UTC)
Bulleted list work too. Much better. Dziękuję. Nyth63 00:58, 30 January 2016 (UTC)

Picture

What is the purpose of the picture that conveys no information about the planet and shows just a black blob? Im sure readers can imagine a big black blob without being shown one. WP is NOT a tabloid newspaper: I suggest this useless image is removed.--213.205.192.13 (talk) 01:09, 30 January 2016 (UTC)

It conveys a great deal of information; it conveys how far away it is from the Sun; it conveys that it is likely similar in form to ice giants like Neptune, and it conveys that it is likely very dark. Serendipodous 02:02, 30 January 2016 (UTC)
Im talking about the picture, not the caption under it.--213.205.192.13 (talk) 04:29, 30 January 2016 (UTC)
So am I. Serendipodous 09:10, 30 January 2016 (UTC)
I agree the artistic representation contributes the situation of Planet Nine in ways many words can't as easily convey. It's serving a good purpose. --Smkolins (talk) 11:35, 30 January 2016 (UTC)
Total codswallop. It contributes a big fat zero. (to me any way). Im going to remove it.--213.205.192.13 (talk) 01:43, 31 January 2016 (UTC)
Really. I would suggest reading up on how Wikipedia works before making that move. Wikipedia operates on consensus, and if you go against consensus you may be blocked.Serendipodous 02:14, 31 January 2016 (UTC)

Off main page

The article has now dropped off the main page, in case someone wishes to reconsider the page protection... --Ørjan (talk) 03:03, 31 January 2016 (UTC)

Diagrams

The orbital diagram might need checking, or compared to second Celestia one which also lists all 6. At least the argument of perihelions give in the table at Planet Nine#Case for a new planet don't clearly match although the 3D effects might be a part of it. It might be nice to have an image like the right Celestia one with different colored orbits showing the 6. Tom Ruen (talk) 13:43, 29 January 2016 (UTC)

Looks ok to me. I assume the perspective on the left is cherry picked for presentation, where-as the one of the right was just randomly selected and was meant to show 2-body orbital solutions with extreme aphelion (without regard for perihelion being outside Neptune). -- Kheider (talk) 14:43, 29 January 2016 (UTC)
It would be helpful to know which direction (toward which constellation) one is looking in these diagrams. Jonathunder (talk) 15:16, 29 January 2016 (UTC)
The 2 perspectives might close, perhaps mirror images, viewed from opposite north/south points of view. But the orientation of the ellipses is more confusing. Like 2010 GB174 looks close to Sedna, but has ω 348° not close to Sedna's 311° while Sedna no where near 2013 RF98's closer 316°. Tom Ruen (talk)
Generally agreed. Notice VP113 near Sedna in the right one but far on the left one. Significantly off angle to the "right" from the original to the new one and a quarter rotation I think, plus other objects in the mix adding to the confusion. (but perhaps reminiscent of the discussion of other objects Chad Trujillo and Scott Sheppard analyzed. --Smkolins (talk) 19:33, 29 January 2016 (UTC)
Trans-Neptunian objects with perihelion greater than 30 AU and a semi-major axis greater than 150 AU
Object Semi-major axis
(AU)		 Perihelion
(AU)		 Eccentricity Argument of perihelion
(ω)
Planet Nine (hypothesis) ~ 700 ~ 200 0.6 150°
2007 TG422 501 36 0.93 286°
2012 VP113 263 80 0.70 294°
90377 Sedna 506 76 0.86 311°
2013 RF98 317 36 0.88 316°
2004 VN112 327 47 0.85 327°
2010 GB174 351 48 0.87 348°

@Tomruen: I've only just spotted this section. Please see the section above where I have added more diagrams with the orbits in different colours, viewed from the north celestial pole, same as the Caltech video. nagualdesign 03:40, 31 January 2016 (UTC)

perspective

direction of view for this figure?

Anyone who knows the direction of view the depiction of the Orbits shows? --Itu (talk) 15:51, 25 January 2016 (UTC)

it's already described in the article if I understand your question. The aphelion is towards Orion/Taurus and the perihelion is towards Sagittarius/Scorpio in the animation but if you look at the RA/Dec graphs it seems like the average perilion is more centered aroun Ophiuchus/Seprens/Libra. --Smkolins (talk) 17:19, 25 January 2016 (UTC)
<File inserted> --->
I asked for the viewing-direction of picture. --Itu (talk) 18:16, 25 January 2016 (UTC)
Looking towards the solar system. Sol in the center. Jehochman Talk 18:51, 25 January 2016 (UTC)
Very funny answer. Since this is wikipedia, i fear you are serious. --Itu (talk) 19:27, 25 January 2016 (UTC)
If you are asking about the face on view of the solar system orbits it would be roughly the north pole of the sun which is roughly in the direction of Polaris as it is from the Earth. Watch the video of the orbits and you can make out constellations in the background. See http://video.scientificamerican.com/services/player/bcpid73042993001?bckey=AQ~~,AAAAAFNl7zk~,OmXvgxJOvrFTWo2Mq0GFTD7z8674te1s&bctid=4713395328001 - in the animation the bright star to the right of the sun at the beginning is almost certainly Canopus though it is hard to pick out the southern direction, but then it rotates north and to the right and Orion and Taurus come clearly into view. --Smkolins (talk) 20:39, 25 January 2016 (UTC)

Actually, this image seems to have a few errors. While comparing different images from the 'net I noticed that the orbit of Planet Nine is much larger here compared to the Caltech video, but worse than that it appears to have been flipped. The Caltech video clearly shows a normal 'top down' view of the Solar System with the planets orbiting anti-clockwise. This image has had all the orbits flipped vertically, which might pass for an unorthodox 'bottom up' view of the Solar System were it not for the stars in the background. nagualdesign 02:35, 27 January 2016 (UTC)

not a good idea to use the file above, sorry. This is without the probably fantasy background
User:Nagualdesign: Please do not take that star scenery as factual, afaik it's fantasy, do not know why you're using that file here, at least i have no evidence the stars are factual somehow. So better refer to the stars-free graph. --Itu (talk) 03:34, 30 January 2016 (UTC)
Let me be clear, I'm actually complaining because the stars are probably not real. It looks like somebody has fudged the image to me. It is not me using this image here or anywhere else and I have already stated that, IMO, the image background should be plain black or white. Since the only person who has replied to me has completely misunderstood my point I will ask more forcefully:
Why are we using an image that has apparently been flipped vertically? The Caltech images show a standard 'top down' view of the Solar System with everything (?) orbiting in an anti-clockwise direction, but this image and every other image based on this one, including those with a transparent background, are in effect shown 'bottom up'. Why? Ordinarily I'd have just flipped the image back in Photoshop, repaired the labels and overwritten the original, but since this image is used on a dozen or so different language WPs I assumed that there was a logical reason why Sedna has been moved from the bottom of the image to the top. nagualdesign 22:53, 30 January 2016 (UTC)
Sorry for beeing misunderstood. I didn't mean you personally at all, but EN-WP in common. --Itu (talk) 06:41, 31 January 2016 (UTC)

I've figured out your objection is to the picture rather than the video it simulates. Yes the orientation is flipped looking north vs south and so things are flipped. But the pedigree of the picture is pretty clearly ok to use - Science Magazine's animation to youtube at [3]. Second your observation that the size of PN's orbit has been enlarged - first of all the B&B website with RA/Dec clearly shows that there are a range of orbits and in fact the overall depth of the orbit to aphelion (relative to Sedna) should be near to or father than Sedna in most estimates while the Caltech one seems clearly shorter. I don't know for sure but it could conceivably be a orientation issue making it look shorter than Sedna's but I don't think so. … I've come to the conclusion that the flipped image isn't using the Caltech animation for the star background - it is indeed made up probably. However, on the basis that the PN aphelion is shorter than Sedna's in the Caltech video and the picture you created based on it - I have serious qualms it is the right picture to use. Yes the orientation is flipped and the stars fictitious but I believe it does a better job representing the orbits than the released Caltech video and the picture following it closely. Now if someone were to combine all the best qualities…. --Smkolins (talk) 04:59, 31 January 2016 (UTC)
First of all, thank you for your considered reply. It seems that the Science Magazine video is at odds with the Caltech video, since the orbits of Sedna and 2010 GB174 are shown widdershins of the other TNO orbits. And since Caltech are the originators of this report I'm inclined to believe that something has been lost in translation. Since the current margin of error allows for a much larger orbit for Planet Nine I'd be happy to adjust the images I provided below. How big should the orbit be? Also, the small circle that I've marked as the Kuiper belt; is that actually supposed to be the orbit of Neptune? nagualdesign 05:23, 31 January 2016 (UTC)
Well most of the published references to the distance of aphelion suggest larger than Sedna. Additionally it is clear there is a range of orbits so emphasizing only one pov on the orbit would be misleading - so perhaps an animated gif showing many possible orbits (tough to do without hard parameters and how to convey variation- a question mark per orbit appearing before being replaced?) I'm not worried about the Kuiper Belt vs Neptune. At the scale of the orbit of these things they would be indistinguishable on the inside edge though maybe check the outer edge of the belt vs the perihelions of the various extreme TNOs and inner Oort objects(Sedna and VP113). I'd also be careful that the aphelion and perihelion of PN aren't the only variations - eccentricity and orientation in space should vary. And no single orbit should stick in the mind if it can be helped so maybe end in a blur??. It might even be interesting if the animated gif could wander view angles but not too much to get people lost. Another important issue coming to mind is that the north celestial pole, the orientation perpendicular to the ecliptic, isn't the actual preferred direction to get the "face on" view of the orbits of extreme TNOs and PN - so orient specifically based on the average inclination projected for PN please. Otherwise perspective issues could make things odder than they'd have to be. A very strong point in the predictions is that PN is herding the extreme TNOS in about the same plane to one set and perpendicular to another set (alas see section below, we've not been able to determine what set that really is save one member.) All that I'm sure would be a lot of work, but it would be an improvement for sure!--Smkolins (talk) 11:50, 31 January 2016 (UTC)


More images based on the Caltech video
Black background White background Transparent background
...Okay, I took the liberty of uploading some more images (above). I'll leave it to others to work out what to make of all this. nagualdesign 00:16, 31 January 2016 (UTC)
Please consider making SVG files. But what is the source of this version? --Itu (talk) 06:38, 31 January 2016 (UTC)
Unfortunately I cannot make SVGs. However, after closer inspection I have been able to update the above images so that they are exactly the same as the Caltech video (compare this to this). nagualdesign 11:34, 31 January 2016 (UTC)

more possible sources to include...

Not must use, but things that attracted my attention:

  • Editorial: Make no little planets, Chicago Tribune, Jan 29, 2016 - about naming ideas
  • Would New Planet X Clear Its Orbit? - And Any Better Name Than "Planet Nine"?, By Robert Walker, Science2.0, January 29th 2016 - about naming ideas and status as a planet
  • For Planet-Seekers, a Cautionary Tale, ScienceFriday, NPR, Jan 29, 2016 - followup on history on past failed discoveries
  • Kevin Peter Hickerson (Jan 29, 2016). "Konstantine Batygin, Amir K and the trillion percent certain discovery". Surely your joking. Caltech.edu. {{cite episode}}: Cite has empty unknown parameter: |seriesno= (help) - background interview, development of the paper, cultural context? (starts around 19 min into the recording, is it possible to bookmark the cast to then?) BTW I think Batygin said there was a 2/3rds chance they'd find it in 2016 (58:22-5 into the interview) - perhaps mapping the near-aphelion region first where it spends more time.
  • Evidence of a Ninth Planet, Caltech, Jan 20, 2016
  • New evidence suggests a ninth planet lurking at the edge of the solar system, by Joel Achenbach and Rachel Feltman, The Washington Post, January 20, 2016 - general summary etc

--Smkolins (talk) 17:27, 30 January 2016 (UTC)

Apropos sources, http://www.findplanetnine.com/ seems to have disappeared (DNS gives nothing, and whois says it was updated 30 Jan, a few hours ago.) Hopefully this is just a temporary bug. --Ørjan (talk) 02:58, 31 January 2016 (UTC)

I think that was temporary - they seem fine now. I bet the traffic was high enough they had to move it to a more robust server service. --Smkolins (talk) 04:01, 31 January 2016 (UTC)
Still down here, and from http://www.downforeveryoneorjustme.com/ --Ørjan (talk) 18:00, 31 January 2016 (UTC)
It was on blogger, a Google service, and traffic wasn't all that high. Something else is afoot. Jehochman Talk 20:46, 31 January 2016 (UTC)
Added archive based urls for preservation as well as load balancing. --Smkolins (talk) 23:09, 31 January 2016 (UTC)
Agreed it was hosted on google blog and something else must be going on. Now I can't reach it either. But I find no comments on their twitter feeds yet, or anywhere else. The only other thing I'll throw into the mix of issues here is that on some of the recent interviews there are comments that they've been working on this issue a while - at least years - and that they had already started a survey looking for it (presumably with Subaru) and that there was a 2/3rd chance they'd spot it before the end of 2016, (stated in the Kevin Peter Hickerson interview above if I recall right.)--Smkolins (talk) 18:09, 1 February 2016 (UTC)
And they are back - No content change I can see. --Smkolins (talk) 20:31, 1 February 2016 (UTC)
note here he himself actually says the path include "between Orion and Taurus". --Smkolins (talk) 17:42, 1 February 2016 (UTC)

--Smkolins (talk) 17:46, 1 February 2016 (UTC)

Dead reference

Reference 11, used three times, is now a dead link. www.findplanetnine.com has gone offline. I wonder why. Jehochman Talk 20:44, 31 January 2016 (UTC)

I assume they have exceeded their allotted bandwidth. -- Kheider (talk) 23:05, 31 January 2016 (UTC)
Added archive based urls for preservation as well as load balancing. --Smkolins (talk) 23:09, 31 January 2016 (UTC)
Good news! FindPlanetNine.com is back up. It was just a minor configuration issue. The site should be stable going forward. Jehochman Talk 22:06, 1 February 2016 (UTC)

worth mentioning another large field telescope set to come online in 2023?

I refer to Shadow planet: Strange orbits in the Kuiper belt revive talk of a Planet X in the solar system, by Christopher Crockett Date 2 MAR 2015 DOI: 10.1002/scin.2014.186011021, Science News, Volume 186, Issue 11, pages 18–21, 29 November 2014 - The Large Synoptic Survey Telescope in Chile designed with a large field of view will make a 10-year-long movie of the night sky starting in 2023 looking for extreme TNOS and inner Oort cloud objects. --Smkolins (talk) 13:21, 2 February 2016 (UTC)

the Large Synoptic Survey Telescope is already referred to under *more predicted objects* sub-header that comes under *direct detection* section. J mareeswaran (talk) 14:09, 2 February 2016 (UTC)
opps - someone beat me to it! Nice! --Smkolins (talk) 14:31, 2 February 2016 (UTC)
also we can remove references to Hubble as the James Webb Space Telescope (also mentioned - under radiation) will replace it shortly in a couple of years and the JWST is a much better telescope than Hubble in all ways J mareeswaran (talk) 14:09, 2 February 2016 (UTC)
Why remove it?? I don't mind adding the JW but that hardly is a reason to remove Hubble. --Smkolins (talk) 14:31, 2 February 2016 (UTC)
I moved the Hubble statements to, notes as there is no direct mention of Planet Nine in those statements. It seems to me Notes section is a better fit for this information J mareeswaran (talk) 14:40, 2 February 2016 (UTC)
Pardon me if I'm wrong, but I remember reading they planned to do the survey in five years. This is a testable hypothesis ... if it fails to produce by 2021, I don't see the new telescope as being a direct hunt for this object. Of course, there could be technical problems, someone drops their cell phone on the mirror or something, but you'd need a source to make a direction connection. Wnt (talk) 19:20, 2 February 2016 (UTC)

Lorenzo Iorio

Wikipedia's article on Lorenzo Iorio is suspicious to say the least. The article was created by a blocked sock puppet, and has since been edited by a parade of sock-like accounts. Why do we have an article about a non-notable associate professor? Why are there multiple links to that person from this article? Why are we citing a paper published three days after Batygin and Brown's paper, the former not being peer reviewed at all? This smacks of a COI campaign and a walled garden. We should not include any content sourced to Lorenzo Iorio until these concerns are resolved. Jehochman Talk 12:52, 1 February 2016 (UTC)

I think you ought to address that issue at that page. It seems to me you are deleting relevant and neutral information in anger. Cheers, BatteryIncluded (talk) 13:18, 1 February 2016 (UTC)
One concern for me is I am not sure if the work is credible or peer reviewed. It would help if it was more notable with more references in blogs/journals/magazines/news-articles (regarding his work on this topic - Planet Nine) J mareeswaran (talk) 13:27, 1 February 2016 (UTC)
Friendly bet: I will buy coffee and donuts for all of you if I am wrong. You can name my prize if I'm right. Jehochman Talk 13:56, 1 February 2016 (UTC)

Does this help?

Lorenzo Iorio (31 March 2014). "Planet X revamped after the discovery of the Sedna-like object 2012 VP113?" (PDF). Ministero dell'Istruzione, dell’Universit`a e della Ricerca. arxiv.org. Retrieved 2014-04-10.

Serendipodous 13:32, 1 February 2016 (UTC)

Not at all. Please show me where that's been peer reviewed. The article Lorenzo Iorio has been deleted 8 times. It keeps getting recreated by sock puppets intent on creating a walled garden. That paper has the trappings of science, but it is not peer reviewed. We are giving a non-notable associate professor vastly undue weight by even mentioning him in this article. The only reason its happening is that we've been duped by all this sock puppetry and COI editing. Jehochman Talk 13:41, 1 February 2016 (UTC)
Whether there is an article on him is irrelevant to the question at hand, nor is its recreation history. What I can tell from the ArXiv preprint is that it is to be published in the Monthly Notices of the Royal Astronomical Society, which would definitely make it a reliable source, and hence can be used in the article. --JorisvS (talk) 13:56, 1 February 2016 (UTC)
Has it cleared peer review, or is it in process? Given the history of spamming, COI we need to be extra careful. The history is relevant to make sure we aren't being duped. As an admin I can see that the Loenzo article has been deleted 8 times, but keeps getting re-created out of process. This is irregular. Jehochman Talk 13:57, 1 February 2016 (UTC)

There is nothing very dubious in suggesting that very small perturbation(s) in Saturn's orbit could give hints to the location of a Super-Earth (aka Planet Nine). Saturn's orbit is very well known thanks to Cassini–Huygens. -- Kheider (talk) 13:59, 1 February 2016 (UTC)

It's not the assertion that's dubious, it's the source. Is that source peer reviewed or not? Unfortunately there's been a 7 year campaign to spam this scientist into Wikipedia, so anything connected needs extra scrutiny. Jehochman Talk 14:07, 1 February 2016 (UTC)
I don't care about what may have happened in the past. What I do care about is whether the source is reliable or not, and I can't find anything with it that would suggest that it is not. Possible past dubious editing surrounding a person is not part of deciding whether or not it a publication is reliable if that is in a peer-reviewed journal. --JorisvS (talk) 14:15, 1 February 2016 (UTC)
Is it peer reviewed. Yes or no? I keep asking, and nobody is answering. We aren't here to publish wishful thinking or aspirational papers. When it's accepted and published, then we can include it. Until then, no. Jehochman Talk 14:21, 1 February 2016 (UTC)
Are the claims & calculations by Iorio on Planet Nine correct? anybody reviewed it or commented on it or cited in other papers? J mareeswaran (talk) 14:30, 1 February 2016 (UTC)
@Jehochman: If you would have followed the wikilink I placed in my first comment, you would already have had your answer: Yes. --JorisvS (talk) 15:18, 1 February 2016 (UTC)
Show me where this has actually been published. Anybody can post to the site you've linked to. Anybody can claim a paper has been submitted to any journal. Submission <> publication. Show me the evidence that this paper has passed peer review and been published. Link and quote. Jehochman Talk 15:28, 1 February 2016 (UTC)
As one of the editors who has included his papers I'll say that I relied in the validity of the source of publication (peer reviewed or not is NOT the standard in wikipedia.) I didn't review if he was at best an obscure author and certainly didn't know there was a sock puppet war going on. I think a review of the reliable sources should seek a trail for mentioning his name. If no one does then I support excising his content until such time as things get more straightened out. --Smkolins (talk) 15:41, 1 February 2016 (UTC)
With that as my starting point here's what I have so far:
(so far) If there is a theme in his work it is that irregularities in Saturn's perihelion motion might be related to Modified theories of gravity but still significantly respected field of work if not mainstream. See Modified Newtonian dynamics. His work is referenced in Gravity Probe B, LARES (satellite), and has an older cite before this stuff in Kuiper belt, and Exoplanet. Continuing looking around.... --Smkolins (talk) 16:07, 1 February 2016 (UTC)
You may want to check which accounts added those cites. Were they independent editors, or single purpose accounts that might be connected to Wikipedia:Sockpuppet investigations/Gravitom/Archive. See also Wikipedia:Articles for deletion/Lorenzo Iorio (2nd nomination). I feel that everything in Wikipedia related to this researcher is suspect, as well as any external citations that aren't peer reviewed. The AfD notes that there's a mess of self-citations. This is a classic walled garden, and potentially involves the promotion of fringe theories. Jehochman Talk 16:28, 1 February 2016 (UTC)
I understand the concern. Admins could indeed mass check a variety of articles how things happened. It would be fine with me if someone were to attract an admin and help us settle the matter. Not sure exactly where such things are reported - I'd favor seeking out the admin(s) that killed his article. My presentation of the facts is that there seem to be legitimate comments from other researchers using his work. And his approach is not automatically that the modified theories of gravity are right - indeed his main paper cited here goes the other direction, proposing more restraints on PN in the arena his work has been focused on. This is not far from how the Pioneer anomaly issue went in that a measured anomaly attracted various views and settled on a solution. The details of the Saturn's perihelion might fit a variety of ideas like modified gravity or not. And his latest paper supports PN as an alternative (though modified gravity is mentioned right in the last line.) Right now I don't see an inherently reason to only decide things are bad here and his papers should be ignored. I've not DECIDED for myself things are ok, but so far in actual publishing of papers he has been referenced by other researchers and in seemingly responsible ways, and in other articles, in seemingly responsible ways. I'm waiting to hear more. I think the whole issue of the names proposed is noise in this review. Clearly there are vested pov in lots of things, not least by B&B calling it "Planet Nine". I think for the purposes of this review on the saliency of this researcher that that issue be just ignored and not brought in in favor or against anything. --Smkolins (talk) 16:39, 1 February 2016 (UTC)
So far only some worry on issue of sock puppets. The Gravity Probe article seems to have none [4], though Lares did have one User:R150634I([5]) and clearly had a war of sorts on the Talk:LARES (satellite) page. But I note some common editors between he articles that seem reputable - User:Headbomb and has a significant footprint as a responsible contributing editor as is User:WolfmanSF. User talk:WDGraham is also common between the articles but is presented as a retired contributor. That's what I get reviewing down several users in the contributions list. --Smkolins (talk) 17:12, 1 February 2016 (UTC)

The arXiv link to Iorio's paper doesn't state where it will be published. The MNRAS layout of the paper suggests that it was written for submission to MNRAS (or MNRAS Letters) but a check on the MNRAS website does not indicate that it is already in the pipeline (i.e. undergoing a refereeing process) or that it will be published anytime soon in one of the next issues of MNRAS. Summing up, Iorio's paper has not yet been published so the reference to it should be removed. AstroLynx (talk) 16:58, 1 February 2016 (UTC)

Iorio is a very peculiar case. AFAICT, he's a notable person. He's just one with a downright hatred of Ciufolini, and the hatred seems mutual. Their dispute/feud has spilled over peer reviewed articles, blogs, forums, popular press, and their own Wikipedia articles, and involves anonymous harassment, socking, fake accounts, etc.. (and not just on Wikipedia). I have no opinion of who is right, who is wrong when it comes to Ciufolini and Iorio, but whenever I see either names, I roll my eyes because they are amongst the most unprofessional-behaving scientists I know.
In full disclosure, it could be that it's only one of them doing the majority of the mud-slinging and grossly unprofessional behaviour, and I'm just mixing the two because their dispute is so convoluted and spans so many years and forums. But I wouldn't trust anything either say about the other. They have been at each other's throats for years.
But is he notable? Yes he is. Are his writings acceptable as sources? I would argue that only in the case where they have been published in a high-reputation peer-reviewed journal. Many of his papers qualify. His preprints don't.Headbomb {talk / contribs / physics / books} 17:27, 1 February 2016 (UTC)
Thanks for the comments Headbomb - I see what you mean: [6]. --Smkolins (talk) 18:22, 1 February 2016 (UTC)
Yes, thank you for the background info. It looks like the dirty tricks have spilled over into Wikipedia. Most likely it's best if we are very cautious and only use sources for this researcher that have been published -- no pre-prints or personal blogs. There's too much risk of unreliability. There is no hard and fast rule for reliability. Each case needs to be judged on the circumstances. A source may be reliable for one sort of fact, but not for another. Jehochman Talk 18:49, 1 February 2016 (UTC)
Hello. I am a relative of Lorenzo Iorio, so you may judge me as unreliable by default. Nonetheless, I wish to share with you some third-party links which, to my judgement, should display his notability:

[7] [8] [9] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [30] [31] [32] Moreover, NASA ADS gives a Hirsch index of 36, with more than 2580 genuine citations. I don't think his page should have been deleted. Is it possible to appeal against this decision and/or restore his page? Thank you. Regards. 21a12 (talk) 19:10, 1 February 2016 (UTC)

I went thru all the English links above & my concerns still remain. Iorio's work is not peer reviewed or no public comment on his work by other scientists/physicians/researchers. He also seems to make assumptions to simplify his calculations and the validity of these assumptions also is not clear or has been questioned and Iorio has also updated his papers with new versions/corrections, so it might not be appropriate to use his research papers as primary source in an encyclopedia as there is a risk that the sourced claims are wrong J mareeswaran (talk) 13:53, 2 February 2016 (UTC)
Hi 21a12. You're already on my list of probable sock puppet accounts. To avoid the need for investigations, blocks and any bad will, why don't you just pick one account, stick with it, and retire all the others? Let the past be past. By "you" I mean you personally as well as any friends or associates working with you toward the same goals. Thank you for the links. I'm sure somebody will look them over, such as @JzG:. Jehochman Talk 19:35, 1 February 2016 (UTC)
Thanks. Actually, I think that the spat between my relative and the other italian physicist may have somewhat disguised the issue of the notability of the page on my relative. I am not sure it is relevant in this context. I also think that too much attention may have been given on who have or could have edited the page instaed of its content. Perhaps, it would be better to inspect the rules set for notability in the scientific field and the actual content. I also think that such decisions should not be taken by people who are not of the same field: it would be better to involve in the discussion other physicists/astronomers/astrophysicists. What do you think? Regards. 21a12 (talk) 20:18, 1 February 2016 (UTC)

I notice that Batygin and Brown do mention a couple of Iorio's papers in the introduction of their paper.Agmartin (talk) 18:14, 3 February 2016 (UTC)

True but only to argue against the orbital assumptions eccentricity assumptions of Trujillo & Sheppard. Never to actually support the reference to a high eccentricity planet in his other paper (2010).--Smkolins (talk) 14:50, 4 February 2016 (UTC)

Whack-a-mole

I think it's time for a round of the sysops' favourite game. I started with 21a12, who is so obviously not a new user that they can probably hear quacking all the way to Planet Nine. Guy (Help!) 22:43, 1 February 2016 (UTC)

viewing stats seems stuck

I think since the original moving/merging/unmerging of the article's title the viewing stats have gotten lost - see [33]. I've no idea who to report this to. --Smkolins (talk) 17:11, 4 February 2016 (UTC)

precession of the Saturnian system addition

On the basis of fully published articles rather than submitted articles only I'd like to suggest pressing ahead with the overall content of the issue.

So factoring in the above I suggest something like:

Researchers like Elena V. Pitjeva (name others? I keep seeing "teams of astronomers" but no names) have been noticing a variation in the precession in the perihelion point particularly of the Saturnian system thanks in part to the precision availed by the Cassini orbiter spacecraft.(citing all above.) Speculation as to the cause included that of an undiscovered planet and other approaches have not succeeded in explaining the observations; in particular Lorenzo Iorio speculated "rock-ice planets of the size of Mars and the Earth … at about 80-150 au, [upto]… a Jupiter-sized gaseous giant would be at approximately 1 kau".(cite 2011 paper above.) In a pre-print paper submitted a few days after Brown and Batygin's paper was published, Iorio analyzed the predicted planet's effect on the perihelion precesion of Saturn. The result restricts the predicted planet's current position (mostly) towards an aphelion direction of 150−200° and distance of 930–1027 AU, and that future analysis of Saturn's perihelion could further narrow down the orbital parameters of Planet Nine.(original cite for that part.)

Moreover I suggest this be in line with the other predictions from the More predicted objects currently under Direct detection but renamed More predictions. --Smkolins (talk) 13:20, 2 February 2016 (UTC)

Found a magazine article on the subject but emphasizing other ideas than that of an undiscovered planet - The Puzzle Over Saturn's Orbit (cont'd), MIT Technology Review, June 1, 2011
Found another paper citing Iorio but emphasizing the modified gravity suggestion - New upper limits on deviation from the inverse-square law of gravity in the solar system: a Yukawa parameterization, Research in Astronomy and Astrophysics, by Zi-Wei Li, Sheng-Feng Yuan, Chang Lu and Yi Xie, 2014 Vol. 14 No. 2, 139–143 doi: 10.1088/1674–4527/14/2/002
Found another paper following the modified gravity idea - [www.scirp.org/journal/PaperDownload.aspx?paperID=19258[predatory publisher] Gravitational Model of the Three Elements Theory],by Frederic Lassiaille, Journal of Modern Physics, 2012, 3, 388-397,May 2012, http://dx.doi.org/10.4236/jmp.2012.35054

No preprints! There are too many fringe theorists. If you want to write about Saturns orbit please go to Saturn. As yet nobody has done an analysis through peer review that links Saturn to Planet Nine. Jehochman Talk 13:59, 2 February 2016 (UTC)

Most of these are NOT preprints and many of these are NOT from Iorio. Only the last one is a pre-print I think. Please read through this carefully. The quoted prediction in the middle is NOT from a pre-print. I think this is a case, similar to the pioneer anomaly, where a variance in the observed details was grabbed unto by various non-mainstream ideas and instead might be do to the predicted planet. Even if we kept strictly to "no preprints" that only cuts out from "In a pre-print paper…" which is the second half of the paragraph. --Smkolins (talk) 14:16, 2 February 2016 (UTC)
On the point of refereed - I note it is called a refereed journal at [34] and there are 22 cites to refereed journals to this paper. But again I refereed journals are NOT the standard (though of course they are given more weight than non-refereed journals.) --Smkolins (talk) 14:35, 2 February 2016 (UTC)
Planet Nine is nothing more than a Super-Earth answer for "Planet X". -- Kheider (talk) 14:20, 2 February 2016 (UTC)
It seems like you are both tripping over particular terminologies used rather than what the papers are actually saying. Even Brown refers to Planet X and in 2011 no one had another term to use at all. PLEASE ACTUALLY READ the papers and the proposed paragraph. --Smkolins (talk) 14:27, 2 February 2016 (UTC)

Even a blind cat catches some mice. There's no value in crank papers even if the prediction is right by dumb luck. We are not here to write about fringe theories. At this point there's no reliable source connecting Saturns orbit to this particular theory of Planet X. You can add above material to Saturn and/or Planet X, leaving out pre-prints. Nothing you've written conndcts to this specific theory. What you've got connects to the genetic theory of Planet X. Jehochman Talk 14:36, 2 February 2016 (UTC)

Does [35] (2010 version of the 2011 paper pointed to above) satisfy your threshold or not? My point is NOT to draw attention to modified gravity or dark matter or relativistic corrections, but to a prediction well published among a set of ideas and then on the basis the paper saying that the other proposed ideas don't work by Yamada and Asada, allowing the preprint paper narrowing the location on PN. If you follow the well published material it goes like this: a separate observation of an anomaly (rather than extreme TNO perihelions) leading to a possible prediction, followed by argument against alternative ideas that don't need to be detailed, then using the PN proposal to against this prediction to narrow down the placement of PN. --Smkolins (talk) 14:47, 2 February 2016 (UTC)
It looks to me that " General Relativity and Quantum Cosmology" is a refereed journal: [36]. --Smkolins (talk) 15:04, 2 February 2016 (UTC)
Note that General Relativity and Quantum Cosmology is not a journal, however there is a book with a very similar title Frontiers in General Relativity and Quantum Cosmology Research. AstroLynx (talk) 15:27, 2 February 2016 (UTC)
Yeah, not interested in something of similar same name rather obviously. But thanks for correcting that GR_QC is not a journal but apparently some collection Cornel is using to organize papers. OI! Frustrating! I also see one of the papers was withdrawn. --Smkolins (talk) 16:37, 2 February 2016 (UTC)
regarding arxiv.org, a check of the comments on the arxiv page will reveal whether the preprints are articles which have been submitted or accepted by a journal
Another team of astronomers noting the Saturn perihelion precession anomaly appears to be lead by someone named Fienga See page 8 at [37]. --Smkolins (talk) 15:31, 2 February 2016 (UTC)
The issue with gravitational anomalies is that there are many possible explanations -- MOND, undiscovered plants, dwarfs, dark matter, witchcraft. It takes some extraordinary research efforts to show anything well enough to get it published in a real journal. Otherwise, there are a lot of cranks running around with very convincing-looking (but never peer reviewed) papers, trying to show that Einstein and general relativity are wrong. We have to be extra cautious in this field because of all the smoke and noise. Jehochman Talk 17:00, 2 February 2016 (UTC)
I'm aware of all of that. I thought I had covered the objections pretty well. I tried at least. The whole idea was that all those other (arg, common, witchcraft?) explanations appeared to be being excluded just as the pre-B&B work had other explanations (notably the less extreme TNOS could have their arguments of perihelion aligned because of resonances with Neptune.) They just hadn't reached the point in the precession-of-Saturn's-perihelion question to make a more specific argument for a planet. Anyway. Frustrating experience but there it is.--Smkolins (talk) 17:25, 2 February 2016 (UTC)
I didn't look into this case, but note the standard here is we need a reliable source to make the link between the two hypotheses. This is the linked-citation test I mentioned in the Telisto section. Beware WP:original synthesis. We have to make sure that general Planet X type descriptions that aren't specifically evaluated by some source as linked to this are kept separate. We can have a paragraph about other Planet X ideas, but only if we remain very careful not to make it sound like they're all Planet Nine without evidence to say so. Wnt (talk) 19:25, 2 February 2016 (UTC)
Agreed on reliable sources. That was the point but it became tied up with the fact that there is noise in the system of papers. Then the standard rose to refereed papers and there was even more noise vs signal trying to figure out if there were actually refereed papers. Such papers as existed from 2010 included predictions of a close match to P9 by size and distance and maybe eccentricity - info not at my finger tips. Then after B&B's article Iorio came out with a pre-print using the B&B predicted specifics on Iorio's data set about the precession of Saturn's perihelia and narrowed the prediction of B&B's planet. But it's a pre-print of someone with many papers and most of this analysis of the precessing perihelia was in another whole context (modified gravity) which had the air of a non-mainstream focus which then drew the ire of folks between partially reliable publications and non-mainstream ideas even though to my reading Iorio was arguing against modified gravity and for a P9-class object by mass and distance at least. But it seemed all too complicated in a wikipedia context. Perhaps B&B and Iorio are talking it out. --Smkolins (talk) 19:17, 4 February 2016 (UTC)

Size

Size can mean mass, diameter, or volume. The "size" of Planet Nine is an estimated range. The diameter of Planet Nine will depend on mass. Quite often a higher mass results in a smaller diameter. Uranus is "larger" than Neptune because Neptune has a "larger" mass and higher density. -- Kheider (talk) 16:36, 4 February 2016 (UTC)

This isn't a 3 digit sig figure examination. This is a rough estimate. If you want to stick to the 2-4 Earth's diameter you'd need to be say something like .3 to .5 Earths but I think that looks too specific. In terms of internal issues of the size of things your points all accepted. But the paragraph describing the size uses observable exclusions pointing to Neptune as the comparison and so the vs-Neptune size is relevant to it's observational situation. --Smkolins (talk) 17:15, 4 February 2016 (UTC)
Earth has radius = 6000km and Neptune has radius = 25000km. (6*4=24.) So again, why are we claiming P9 is "about" half the diameter of Neptune?-- Kheider (talk) 17:46, 4 February 2016 (UTC)
Radius vs diameter. --Smkolins (talk) 18:26, 4 February 2016 (UTC)
Yes, 'half' is clearly wrong there. If '2-4 Earth diameters' is all the information we have on Planet Nine's dimension, it is acceptable to add something like '0.5-1 Neptune diameters'. Such a simple conversion wouldn't be OR, and no citation would be needed. Maybe 'about half that of Neptune' was intended to apply to mass? Gap9551 (talk) 18:10, 4 February 2016 (UTC)
Wo wo wo. 2-4 Earth diameters. Neptune's radius is 3.8 Earths (polar or equatorial) So Neptune is 7.6 Earth diameters. So 2/7.6=0.26 and 4/7.6=.52. No way PN is "1 Neptune" diameter. Rounding back you could argue for .3 to .5 Neptune's but to me that implies more precision than we have. If you want some kind of strict middle ground you could say .4 Neptune's. But that too seems to me to be too precise. So "about half" seems right to me. The point is in the context of excluding Neptune sized objects from 700 AU this is "under the radar" so to speak. The previous work excluding larger objects doesn't exclude smaller-than-Neptune, as in "about half". Is there a strong argument to be more precise than "about half"?? --Smkolins (talk) 18:21, 4 February 2016 (UTC)
NO. Neptune's radius (or diameter) is 3.8x Earths. Diameter=radius*2. -- Kheider (talk) 18:30, 4 February 2016 (UTC)
Re:So Neptune is 7.6 Earth diameters That's wrong. Neptune's diameter is about 4 times Earth's diameter. Or equivalently, Neptune's radius is about 2 times Earth's diameter. So, Planet Nine's radius is 0.5-1 times Neptune's radius, or Planet Nine's diameter is about 0.5-1 times Neptune's diameter. Gap9551 (talk) 18:32, 4 February 2016 (UTC)
The description relative to Earth's DIAMETER is in the article. Wikipedia's stats on Neptune say RADIUS. So double the 3.8 to have a size on the same variable - diameter. So (3.8*2=) 7.6 Earth diameters. Or in your terms 6k km Earth becomes 46k km Neptune. Which is about right 48k km diameter. --Smkolins (talk) 18:37, 4 February 2016 (UTC)
Let's take a step back here. Do you agree or disagree with the NASA source Kheider gives, that lists a 3.829-3.883 ratio between the Neptune/Earth radii? (or equivalent, ratio of diameters)? Gap9551 (talk) 18:40, 4 February 2016 (UTC)
Yes. I see I mixed up a two in there somewhere. 7.6 Earth Radiuses is 1 Neptune diameter. --Smkolins (talk) 18:46, 4 February 2016 (UTC)

OK so what do people want half to about the diameter of Neptune? More than half? What loose approximation fits the paragraph?--Smkolins (talk) 18:48, 4 February 2016 (UTC)

It's not trivial to phrase it well. First of all, I'd use two sentences. Maybe: 'The planet is estimated to have 10 times the mass of Earth,[10][9] or just over half the mass of Neptune. Planet Nine has an estimated diameter of two to four times the diameter of Earth,[6][16] or about 0.5 to 1 times the diameter of Neptune.' It would be better to use words instead of '0.5 to 1', if anyone has a good suggestion. Gap9551 (talk) 18:55, 4 February 2016 (UTC)
Well aside from my stupid math error in my head I don't think this deserves so much discussion. Without getting in to synthesis the idea is that it fits within the exclusion of a neptune sized object at 700AU - smaller is ok as is that size and father (and the aphelion is ~~1200AU). The problem with the paragraph as it stood as it left people wrestling with Earth diameters compared to Neptune size. Clearly at least some of us can get that mixed up so I wanted to make it more explicit (and blew it.) But I don't think it deserves a solid range. --Smkolins (talk) 19:01, 4 February 2016 (UTC)
The aphelion is 1200 AU, so even if it is larger than Neptune, that wouldn't contradict the WISE result (if the planet is currently beyond 700 AU). I see where you're coming from when you mainly want a rough comparison to Neptune. But 'about more than half that of Neptune' (current version) is pretty vague, and there may be readers who want a more precise comparison with Neptune. The range of a factor of two centered around 0.78 is not easy to grasp in a single rough approximation. I'd prefer explicit ranges, for the comparison with Earth as well as with Neptune. Let's wait for others to weigh in. Gap9551 (talk) 19:24, 4 February 2016 (UTC)
This conversation demonstrates that we should discuss mass and diameter in two different sentences. If P9 has a composition and mass similar to Uranus it could have a diameter (~51000km) slightly larger than Neptune (49600km). -- Kheider (talk) 19:37, 4 February 2016 (UTC)

normal commenting for Mike

Hi Mike, and like others, I share a big "welcome". It's an honor to have you among us trying to make articles better in wikipedia. Normally you should create an account and use that identity as the basis of posting. So look for that "login" option on the top right and go from there. Fairly quick and painless. Once logged in your browser will hold a cookie for 30 days (presuming you checked the box) and it will be easy to stay "logged in" and then at the end of comments just add --~~~~ at the end manually or the editor box has a "signature" button that depends on the view you use and it will pop all the details in once you save the addition. And once you have an account you can then have individual comments like this one on your "talk" page. If you choose to go that route. Thanks for commenting.--Smkolins (talk) 21:08, 5 February 2016 (UTC)

Also keep in mind everything in wikipedia is recorded - so you already have the anonymous talk page at User talk:131.215.64.52.--Smkolins (talk) 21:18, 5 February 2016 (UTC)

Apparent magnitude range estimates

Here's a qualitative example of its potential parallax motion near 1000au distance, with the earth's revolution motion, varying ~ ±4 arc minutes east/west over 1 year. At a 20,000 year period, its revolutionary motion eastward would be about 1'/year on average, but more like 20"/year near aphelion as seen in the ellipse drifting left.

Just for curiosity, using Absolute_magnitude#Solar_System_bodies_(H), simplified as viewed from sun, = and is the distance between the observer and the body d=(200-1200 AU), with H similar to Uranus/Neptune, -7, this comes out to = ~ 16 to 24 between perihelion (200au) to aphelion (1200au). (I also calculated its apparent diameter would range between 0.05-0.2 arc seconds, a similar apparent diameter as Pluto, 0.1", although MUCH dimmer surface brightness.) Tom Ruen (talk) 12:30, 6 February 2016 (UTC)

That is inline with B&B as P9 could have perihelion @ 200-350AU depending on mass. -- Kheider (talk) 13:03, 6 February 2016 (UTC)
That's good! Thanks. Tom Ruen (talk) 22:17, 7 February 2016 (UTC)

Sednitos

Recently, Trujillo & Sheppard (2014) discovered the object 2012 VP113, a second member of the inner Oort Cloud, which they defined as a family of planetesimals with q (> and ~, cannot correctly represent symbol) 50 au and a ≈ 150–1500 au. They furthermore identified a population of planetesimals between the Edgeworth–Kuiper belt and the Oort Cloud that share similar orbital elements (see also de la Fuente Marcos & de la Fuente Marcos 2014), namely the large perihelion and semimajor axis (q > 30 au and a > 150 au, respectively), inclination with respect to the ecliptic (i =10° –30° ), and the argument of perihelion (ω = 340° ± 55° ). Currently 13 such objects have been observed in the outer Solar system and it was suggested that their character- istics resulted from a common origin (de la Fuente Marcos & de la Fuente Marcos 2014; Trujillo & Sheppard 2014). Here we consider this group of object a family which we call Sednitos.

--Smkolins (talk) 18:50, 7 February 2016 (UTC)

that is an alternate (failed?) hypotheses(refer NOTE C) that assumes that the orbits of the "sednitos" have not modified over time due to influence of outer planets. very unlikely as per B&B's hypotheses. J mareeswaran (talk) 19:01, 7 February 2016 (UTC)
Not the issue. I posted it because of the clarification requested, not to bring up another theory. --Smkolins (talk) 19:04, 7 February 2016 (UTC)

Are Sednitos suppose to be Sednoids with q>50 a>150 or are they ETNOs with q>30 a>150? If there are 13 "Sednitos" then they are ETNOs as there are only 2 known Sednoids. -- Kheider (talk) 20:00, 7 February 2016 (UTC)

By your definition they are ETNOs as long as you include inclination and argument of perihelion parameters. --Smkolins (talk) 21:58, 7 February 2016 (UTC)
Only the ETNOs with a>250 are notably shepherded by P9. -- Kheider (talk) 22:55, 7 February 2016 (UTC)
I agree, it is just that S&T and M&M started with the broader set of 13 objects (the M&M named Sednitos) that B&B filtered down to 6 and then added 5 highly inclined objects that can have lower perihelions than the 6 but still have large a, ( at least until they have a close enough encounter with an inner giant planet to get scattered out of that group.)
BTW B&B speculate that 150<a<250 might be affected in noticable fashions but it is only a speculation. They say the ω ~ 0° for the inner set "remains somewhat puzzling" (top of page 12.) --Smkolins (talk) 23:58, 7 February 2016 (UTC)
I suspect some of the 150<a<250 objects are the 8 others Brown talks about. -- Kheider (talk) 05:26, 8 February 2016 (UTC)
In any case does this clarify the request at [38] ?
I believe so. I have removed the clarify statement. -- Kheider (talk) 05:26, 8 February 2016 (UTC)

As for "Do we really want to introduce a new term that is only used in one paper?" my view is leave it in the note and we can see how things develop.--Smkolins (talk) 23:18, 7 February 2016 (UTC)

why at 0?

B&B's paper calls the 0° argument of perihelion grossly out of alignment from the 318° they derived from the set of objects filters from being affected by Neptune. The ~0° direction is derived from the mathematical analysis of the Kozai mechanism and the 318° direction is derived from the mean motion resonance and is far from the 0° direction. 318 is clearly different from 0 - how do folks want to say this in Planet_Nine#Brown_and_Batygin?

Of course 0° ≠ 318±8°. The point is a short explanation/indication of why the Kozai mechanism requires an angle of ~0° (or ~180°) and not any other. --JorisvS (talk) 13:01, 6 February 2016 (UTC)
See Extreme trans-Neptunian objects and the Kozai mechanism: signalling the presence of trans-Plutonian planets a quote from section 5
"Another possible Kozai scenario is found when the ratio of semimajor axes (perturbed versus perturber) is close to one. In that case, the libration occurs at ω = 0° and 180°; therefore, the nodes are located at perihelion and at aphelion, i.e. away from the massive perturber (see e.g. Milani et al. 1989)."Agmartin (talk) 17:21, 6 February 2016 (UTC)
318+8 doesn't seem too far off 360 which is same as zero
The point isn't what is obvious as much as what B&B say it is - see page two on the right at their paper [39] --Smkolins (talk) 21:46, 6 February 2016 (UTC)
the point is that T&S included 12 elongated objects but 6 of the inner objects had zero not because of new planet but because of existing planet Neptune. So once you remove these inner 6 aligned at 0 the outer six bunch at 318+-8. B&B thus could rule out a new planet only for inner 6 objects but not outer 6
Agreed.--Smkolins (talk) 21:46, 6 February 2016 (UTC)
B&B also that outer 6 were all approximately orbiting in same plane (ecliptic=30 & argument of perihelion =318+-8). This was a new observation on top of the earlier observation that the perihelia are bunched together. This indicated that there was an undetected perturbed/planet out there on that same plane (ecliptic=30, argument of perihelion= 318 or 318-180=138) J mareeswaran (talk) 17:29, 6 February 2016 (UTC)
And still no explanation whatsoever about why 0° or 180°. For one, why would this be independent of the ω of the hypothetical planet? Then there is also the sentence "The Kozai mechanism causes the argument of pericenter (ω) to librate about either 90° or 270°" at Kozai mechanism, which says something different. In short: What is the logic behind it? --JorisvS (talk) 11:03, 7 February 2016 (UTC)
I don't know why it is 0° - I said much the same thing "How does the Kozai mechanism itself force a result of 0° or 180° (and if it must shouldn't the wikipedia article say so instead of 90° and 270° - I think, don't know but I think, this angle is measured relative to the outer purturber at least in one case and or that of celestial orientation in the other or does it just fall out assuming a certain pattern of purtubers?)? As I read it, it is a 3 body perturbation and it seems to me that some angle must come out the calculation but not why a particular orientation in the solar system must fall out of it or why it would be strongest in the early solar system and not later." above mid-bottom of Talk:Planet_Nine#Comments_from_Mike_Brown. Perhaps Mike or someone can find the math.--Smkolins (talk) 12:11, 7 February 2016 (UTC)
What I can say is that both S&T and B&B say the value should be 0° and B&B show it isn't.--Smkolins (talk) 12:41, 7 February 2016 (UTC)
This website [40] says "The pull of the Milky Way Galaxy causes an object with a high eccentricity to periodically trade this eccentricity for a gain in inclination." so perhaps this is what is driving the orientation as the will center around Galactic coordinates, so 0°, while in celestial coordinates that is at RA 18hrs,which is 270°.[41] and each affect allows for 180° off. --Smkolins (talk) 12:57, 7 February 2016 (UTC)
266.4° to be more exact vs 270° but close enough for something that is an average anyway. However I think to make the case for all this we need a stronger cite.--Smkolins (talk) 13:07, 7 February 2016 (UTC)
in terms of cites so far the best I can find is [42] which is repeated in a few places [43], [44], [45] (not OCRed so have to search manually, see p.10 though that link is dead. The reported direction doesn't say 0° itself though - it refers to "π /2 or 3π /2", which, I beleive, gets us into radians where 2π =360°, so that would be 90° or 270° but it doesn't specify the coordinate system in the abstract.--Smkolins (talk) 13:31, 7 February 2016 (UTC)
I do see S&T referencing galactic tides several times in their article struggling about if they affect inner oort cloud objects. And in particular I don't see that they were modeling the galactic tide itself in this case:

The Lidov–Kozai effect is the best known dynamical mechanism for constraining the v of a minor planet28. This three-body interaction can create outer Oort cloud objects with v preferentially near 0u and 180u early in the history of the Solar System when the Sun was still among its nascent cohort of perturbing stars29. This cannot explain the v ~ 0u trend today, because v circulates owing to the presence of the giant planets. By numerically simulating the effect of the known mass in the Solar System on the inner Oort cloud objects, we confirmed that inner Oort cloud objects should have random v (Methods). This suggests that a massive outer Solar System perturber may exist and restricts v for the inner Oort cloud objects. We numerically simulated the effect of a super-Earth-mass body at 250 AU and found that v for inner Oort cloud objects librated around 0u 6 ± 60u for billions of years (see Extended Data Figs 2 and 3). This configuration is not unique and there are many possibilities for such an unseen perturber.

(note in this copy and paste the argument of perihelion parameter normally shows "ω" as a "v", and "°" as "u" I've been correcting this in my pastings here on the talk page but I'm getting tired of doing so over and over again. I don't know how S&T derived 0° for ω - is it an accident it coincides with the direction applied by the galactic tide?!?!--Smkolins (talk) 13:40, 7 February 2016 (UTC)
I'll repeat this since it appears to have been overlooked, In Extreme trans-Neptunian objects and the Kozai mechanism: signalling the presence of trans-Plutonian planets Marcos and Marcos explain in section 5

Another possible Kozai scenario is found when the ratio of semimajor axes (perturbed versus perturber) is close to one. In that case, the libration occurs at ω = 0° and 180°; therefore, the nodes are located at perihelion and at aphelion, i.e. away from the massive perturber (see e.g. Milani et al. 1989).

In the better known scenario the perturber is in an external or internal orbit (Jupiter for the asteroid belt or Neptune for the Kuiper belt) and the libration is about 90° or 270°. Then the object is at its greatest distance for the plane of the planet when it is at perihelion of aphelion, i.e. closest to the planet. For the objects to be librating around 0° and not 180° requires something else to happen, one example I've seen has the initial population being captured on their orbits by a passing star, this creates a one sided population which is kept in line by Planet Nine. I'll see if I can relocate the reference. Agmartin (talk) 22:04, 7 February 2016 (UTC)
The theory/mechanism quoted above is right, but it seems a relatively new concept not updated in wiki pages of kozai mechanism. Also note the 1:1 ratio(of semi-major Axis) between perturber & perturbed. This requires multiple perturbers for groups of perturbed at different distances. The same point used by B&B to dismiss this mechanism in their paper as it is unlikely to have multiple planets to hold together all these kuiper belt objects J mareeswaran (talk) 05:27, 8 February 2016 (UTC)
From How Sedna and family were captured in a close encounter with a solar sibling

The libration around 0° will occur if the initial relative ω ranges from −90° to 90° (e.g. Mardling 2007). Therefore, the ω of Sednitos relative to the perturber (ω − ωpertuber) needs to be constrained at the beginning of the dynamical interaction with the perturber.

They then go on to model how the capture of Sedna and family are possible in an encounter with another star. Agmartin (talk) 22:18, 7 February 2016 (UTC)

Orbital plane

I understood from hypothesis that orbital plane is more-or-less same(coplanar) for 6 extreme TNOs. But when I look-up the inclination & longitude of the ascending node values for the 6 objects they are not exactly same and there is some variance (12 - 30) for inclination & (65 - 145) for the long. asc. node. Are these values in line with what is discussed in the paper by B&B? J mareeswaran (talk) 18:54, 7 February 2016 (UTC)

Exactly in the same plane isn't the claim. They are close enough to be considered so. The planets themselves are not really in the same plane either - they can vary between ±5° maximum or so - see Ecliptic#Plane_of_the_Solar_System, [46]. link title B&B and others have accepted they are close enough to be considered nearly coplanar. To quote B&B:

"We demonstrate that the perihelion positions and orbital planes of the objects (the 6 that is) are tightly confined …"

--Smkolins (talk) 00:18, 8 February 2016 (UTC)

To be more particular the main planets range in about a 10° wide plane and these ETNOs vary in a 18° plane, so less than twice the width of the inner solar system.--Smkolins (talk) 01:18, 8 February 2016 (UTC)
the introduction of the longitude of perihelion and sorting the table by that value reproduces the exact same order of the 6 objects in the diagram. is that coincidence or expected result? J mareeswaran (talk) 19:51, 7 February 2016 (UTC)
I don't understand the question? Which table sorted which two different ways? --Smkolins (talk) 22:02, 7 February 2016 (UTC)
In the top diagram under the *planet nine hypothesis* section the order of the orbits of the 6 objects (from top to bottom) seems to match the order of the objects in the table below in same section, if the table is sorted by *longitude of perihelion* (in ascending order) J mareeswaran (talk) 04:20, 8 February 2016 (UTC)
It seems for objects which are more or less coplanar the Longitude of Perihelion are comparable. So it makes sense then. J mareeswaran (talk) 18:12, 8 February 2016 (UTC)
Yes though from a different aspect. The idea here is the orientation in space of the orbits is onesided and the P9 candidate direction is on the other side. So yes they are comparably lined up. --Smkolins (talk) 18:28, 8 February 2016 (UTC)

qualifying the predicted parameters

Beyond simply stating the most likely parameters, the B&B paper discusses some other issues of the parameters - first the model is not yet self-consistent and second the mass could easily be well above half Neptune's. If these are true how to represent them…. --Smkolins (talk) 01:57, 8 February 2016 (UTC)

degenerate

I take "degenerate" in the paper to mean the parameters contradict eachother in that if you assume one the other is not resolved.

  • "Although the model proposed herein is characterized by a multitude of quantities that are inherently degenerate with respect to one another,"

Meaning the model of the inclined perturber they specifically varied parameters in didn't arrive at a self-consistent result of all parameters at the same time - indeed they cannot. Yes?--Smkolins (talk) 01:57, 8 February 2016 (UTC)

Degenerate often means there is more than one value (or a range of values) of a variable that fits the data. I take degenerate with respect to each other to mean that for one value of A, there is a value of B that fits the data; but for a second value of A, another value of B fits the data. One example is if Planet Nine is farther away its mass would to be larger. Another example is the relationship between the eccentricity and semi-major axis of planet Nine which gave a perihelion between 200 AU and 300 AU (Eqn 6 of B&B). Agmartin (talk) 19:38, 8 February 2016 (UTC)
Out of curiosity I made a plot of acrit using equation 6. It appears that the perihelion distance needed to get acrit=250 AU decreases as a' increases. Probably due to the increased orbital period making perihelion passes less frequent. Agmartin (talk) 17:58, 9 February 2016 (UTC)

"a factor of a few"*10m⊕

  • "our calculations suggest that a perturber on an a′ ∼ 700 AU, e′ ∼ 0.6 orbit would have to be somewhat more massive (e.g., a factor of a few) than m′ = 10 m⊕ to produce the desired effect."

Meaning they speculate that higher mass than 10 m⊕ by a few factors would work around semimajor 700 au and eccentricity 0.6 - so "of a few" could be 2 or 3 which jumps directly into full Neptune mass range or higher. Yes? This would be still way below Saturn-mass excluded to much further distances but also completely above the "superearth" category of object. Or would "a factor of a few" suggest something smaller like 1<x<2?--Smkolins (talk) 01:57, 8 February 2016 (UTC)

Simply put, the further P9 orbits, the more massive it will have to be. Perihelion could be 200AU or 350AU. Mass is only on the order of 10 Earths. That is part of the reason I did not worry about the whole orbit diagram discussion. -- Kheider (talk) 05:07, 8 February 2016 (UTC)

perpendicular orbital trajectories

B&B list the 6 ETNOs, but does anyone have a source listing the 5 objects with perpendicular orbital trajectories? -- Kheider (talk)

B&B name one in the original paper - 2008 KV42 (aka "Drac"), and that article suggests it is "one of only five objects known to have inclination (i) > 60° and perihelion (q) > 15 AU" - the group being 2007 BP102, 2010 WG9, 2011 KT19 and (127546) 2002 XU93 (and here's a link for the list given - [47]. I can't be sure that the list is correct relative to the paper yet though. --Smkolins (talk) 03:24, 30 January 2016 (UTC)
That is my work from 2013. -- Kheider (talk) 03:33, 30 January 2016 (UTC)
Fine, my point is that Drac is specifically mentioned in B&B's paper: "Gladman et al. (2009) suggested that the presence of highly inclined KBOs, such as Drac, point to a more extensive reservoir of such bodies within the Kuiper Belt." - This Gladman article is "Gladman B., Kavelaars J., Petit J.-M. et al 2009 ApJL697 L91". --Smkolins (talk) 03:41, 30 January 2016 (UTC)
So they are the high-inclination, high-perihelion (HiHq) objects. -- Kheider (talk) 03:49, 30 January 2016 (UTC)
Agreed - the question is, on the basis of specifically listing Drac and the description are we safe listing the 5 objects this way. We may have to say B&B list Drac as an example of this highly inclined KBOs. A list of such highly inclined KBOs is… . Are we on good ice here? --Smkolins (talk) 03:55, 30 January 2016 (UTC)
Yes, we can just use the same style disclaimer as we did for the ETNOs. This link to the MPC is much shorter: http://minorplanetcenter.net/db_search/show_by_properties?perihelion_distance_min=15&inclination_min=60 -- Kheider (talk) 03:58, 30 January 2016 (UTC)
Go for it. --Smkolins (talk) 04:14, 30 January 2016 (UTC)
Done. Feel free to wordsmith it. -- Kheider (talk) 04:26, 30 January 2016 (UTC)

Now that I have checked the B&B paper, they say very little about these 5 perpendicular objects. Even though drac is mentioned in B&B, it has aphelion @ 62AU and none of the 5 listed objects (q>15 and i>60) have aphelion beyond 114AU. The object on the right of the diagram looks like it has aphelion around 2500AU which might be a match for objects like 2012 DR30 (objects with a>400 and i>60.) -- Kheider (talk) 16:00, 30 January 2016 (UTC)

I saw that long arc too and wondered but I also didn't know how much perspective could come into play. So far I've not seen any specific list or been able to generate a super-imposed view of orbits. Might take Celestial software and some serious work trying to recreate the layout and even then can't be sure. I really wish the original paper had been far more explicit about some things - feels like they didn't want to be too public with the info in case too many contenders in searches wanted to give it a go and instead just wanted the publicity to help their cause of funding the prediction search. But then I'm being pessimistic (sigh).--Smkolins (talk) 04:07, 31 January 2016 (UTC)
How many objects are really in perpendicular orbits to the average inclination of the extreme TNOs and Sedna and VP113? Hmm, maybe that isn't so easy to answer…. I figured out the average inclination of those is 21.9° so perpendicular is around 112° (for prograde orbits, or more than -60° for retrograde but nothing is that backwards in the minorplanetcenter data?) and there are 17 objects between 100° and 120°. But all these must have aphelion's out there in the vicinity of the extreme TNOs etc - atleast above 60 with Drac. That ~2500AU object to me looks like 2005 VX3. Problem is I don't get just five - see [48]. Care to tweak any orbital characteristics that bring it to five?? I did notice the argument of perihelion angle above 40° leaves only 5 but I don't see that required in this set from B&B. I also noticed you could restrict the ascending node Ω to be above 120° and get five but again no justification for that in the paper coming to mind.--Smkolins (talk) 12:30, 31 January 2016 (UTC)
I am not sure I like 2005 VX3 because the orbit crosses the ecliptic just inside Jupiter's orbit and has a Jupiter-MOID of 0.8 AU. It looks like one of Jupiter's play toys. -- Kheider (talk) 22:59, 31 January 2016 (UTC)

There are the 6 objects listed in this article, probably the 5 mentioned at 2008 KV42, and 8 others. -- Kheider (talk) 15:59, 3 February 2016 (UTC)

There are eight in the paper with unstable orbits and semi-major axes greater than 150 AU. The 5 high inclination objects in figure 9 of the paper have perihelia of 6.3, 8.5, 9.4, 11.1, and 14 AU and semi-major axes of 323, 348, 484, 1213, 1404 AU frome the JPL small bodies database these appear to be: 2012 DR30, 2013 BL76, 2010 BK118, 418993 (2009 MS9), and 336756 (2010 NV1), the paper also mentions Drac by name but it is not in the figure or in the caltech animation.Agmartin (talk) 22:56, 3 February 2016 (UTC)
Thank you for the post! You can generate those 5 objects with: http://minorplanetcenter.net/db_search/show_by_properties?semimajor_axis_min=250&inclination_min=40&perihelion_distance_min=6 -- Kheider (talk) 01:48, 4 February 2016 (UTC)
Except we have no reason to say they are that specific combination of orbital characteristics. We have orthogonal to the initial set, (which doesn't fit that five set) not simply greater than 40°, and we have high aphelions from the graphs, and nothing about their perihelions. And Drac can come in a variety of ways. Not to mention the other 8 bodies he hints at.Where's the date of those perihelia and semi-majors come from? - O - I see Fig 9 inside the graphs. Hmmm --Smkolins (talk) 02:21, 4 February 2016 (UTC)
I stand corrected - I think the listing should point out the two parameters from the text and the physical list of perihelia from the points on the graph. But it is odd to me that they would stress the five or orthogonal (perpendicular) to the initial set in various descriptions but then not in the actual characteristics. I guess perhaps we should reduce the usage of that description an instead emphaize just that they were highly inclined? --Smkolins (talk) 02:36, 4 February 2016 (UTC)
Though the orbital parameters listed are not identical to the ones in the minorplanetcenter website they seem pretty close. Anyone got qualms?--Smkolins (talk) 02:39, 4 February 2016 (UTC)
As a result of perturbations, the orbital parameters will vary slightly depending on the Epoch (astronomy) used to define them. Aphelion can vary notable due to very small changes in eccentricity. -- Kheider (talk) 03:12, 4 February 2016 (UTC)
And orbits are refined all the time….--Smkolins (talk) 09:24, 4 February 2016 (UTC)

Now I'm wondering if we can sniff out the dynamically unstable ones from Fig 1 - a>150AU, ω<90° or ω>270° (right panel of Fig 1) But that isn't enough to narrow down to eight by a long shot (and inclination and eccentricity seem to be all over the place on the graphs and not well listed anyway.)--Smkolins (talk) 03:10, 4 February 2016 (UTC)

Of the 16 objects listed in the JPL small bodies database 2003 SS422 with an argument of perihelion of 210 is definitely not plotted in Fig 1 of B&B, its observation arc is listed as 76 days, and its semi-major axis is 194 +/- 48 AU. The other one missing appears be 2015 SO20, it may have been reported to late to be included.Agmartin (talk) 19:57, 4 February 2016 (UTC)
table of the 16 from MPCAgmartin (talk) 20:04, 4 February 2016 (UTC)

proposed table for this group

Trans-Neptunian objects with perihelion greater than 6 AU, a semi-major axis greater than 250 AU, and high (>40°) inclination[1]
Object Orbit Body
Perihelion
(AU)
(B&B fig 9)		 Semimaj.
(AU)
(B&B fig 9)		 Current
distance
from Sun
(AU)		 inc
(°)[2]		 Eccen. Arg. peri ω
(°)		 Mag. Diam.
(km)
(336756) 2010 NV1 9.4 323 14 141 .97 133 22 20–45
(418993) 2009 MS9 11.1 348 12 68 .97 129 21 30–60
2010 BK118 6.3 484 11 144 .99 179 21 20–50
2013 BL76 8.5 1213 11 99 .99 166 21.6 15–40[3]
2012 DR30 14 1404 17 78 .99 195 19.6 171[4]
Planet Nine (hypothesis) ~ 200 ~ 700 ~ 1000 ? ~ 30 0.6 150 >22 ~ 40,000
Comet Hale–Bopp
(Comparison) 		0.914 186 38 89.4° 0.995 40–80
  1. ^ B&B paper
  2. ^ [1]
  3. ^ "Absolute Magnitude (H)". NASA/JPL. Retrieved 2013-10-13.
  4. ^ Michael E. Brown. "How many dwarf planets are there in the outer solar system? (updates daily)". California Institute of Technology. Retrieved 2014-02-16.

Ok - so we think this is solid? Should it be simplified? The arg of perihelion isn't an important parameter for this set.--Smkolins (talk) 16:47, 4 February 2016 (UTC)

I'm not clear on what the point of these objects is. All these have perihelia well within the giant-planet region and hence suffer significant scatters by them. What are they supposed to tell about Planet Nine and why? --JorisvS (talk) 17:29, 4 February 2016 (UTC)
I think the simulation demonstrated that the existence of these 5 objects shows that they could have become highly-inclined as a result of interactions with P9. -- Kheider (talk) 17:41, 4 February 2016 (UTC)
Agreed. So this was a prediction-turned-evidence B&B ran into during the development of their paper. If I read the paper and various summaries the idea is that such orbits were derived from a Kuiper Belt/TNO that was perturbed by P9 - some cross into the solar system quite far (almost down to Jupiter if you count among the original 5 with similar arguments-of-perihelion and very high semi-major axes.) But yes these are not stable long term orbits and will change - but P9 will pick out other objects in KB/TNO population and push them into such configurations as these. This is along the times of pumping objects into the (inner relative to it) Solar system on average. --Smkolins (talk) 19:09, 4 February 2016 (UTC)
Right, so the point is that extreme-inclination very-high-eccentricity objects generated by P9 have arguments of pericenter centering on that of P9? --JorisvS (talk) 21:07, 4 February 2016 (UTC)
I think the answer is no - it isn't about them clustered around their arguments of perihelion for these high inclination objects. It's more complicated than that. There is a set of 5 extreme TNOs and inner Oort Cloud objects that have clustered perihelions and other affects that very strictly confine them in space because of the affect of P9 (like they are in approximately in the same plane as well as orientation in space.) Then there is these objects clustered by high inclination and highly eccentric orbits that reach into the hundreds of AUs but who's perihelions can be well in the region of giant planets. This group we're talking about. There is some clustering of some of the parameters of their orbits, not just arguments of perihelion. There is also a looser group less stable, more suggestive of an affect, less easily characterized. --Smkolins (talk) 00:12, 5 February 2016 (UTC)
What distinguishes these from comets? Comet Hale–Bopp is as big. Tom Ruen (talk) 03:28, 9 February 2016 (UTC)
The biggest difference would be perihelion currently inside of Jupiter (q<5) so the orbit would be very chaotic even over the short term (100 thousand years instead of 10 million years). Hale-Bopp also no longer has a semi-major axis greater than 250AU. The last perihelion passage dropped the semi-major axis from 261 AU to 179 AU (barycentric solution for epochs 1950 & 2050). Given the perihelion point, Hale-Bopp would be included with the 9 minor planets (instead of the 5 listed with q>6). Comets are also known to significantly outgas while inside of the orbit of Jupiter making long-term orbital studies even more difficult. -- Kheider (talk) 08:49, 9 February 2016 (UTC)

2004_XR190

any explanations for the curious orbit of 2004_XR190?

  • perihelion = 54 AU
  • aphelion = 64 AU
  • eccentricity = 0.1
  • inclination = 46°

Is it a typical KBO or a detached object? The inclination seems high but no explanation for that? J mareeswaran (talk) 12:09, 9 February 2016 (UTC)

Without a better explanation, it is both. -- Kheider (talk) 14:34, 9 February 2016 (UTC)
Its period is just below a 8:3 ratio with Neptune's. One explanation for its orbit is that its perihelion was raised via the Kozai resonance while in the 8:3 resonance and it escaped from this resonance near the end of Neptune's migration. Agmartin (talk) 17:17, 9 February 2016 (UTC)
Brown has talked about how P9 will occasionally perturb KBOs and move them into detached orbits, and then eventually those objects will fall back down into the Kuiper Belt under Neptune's influence (if I understood correctly). Perhaps this object is somewhere in between, moving out or back in. Jehochman Talk 18:00, 9 February 2016 (UTC)
But the 8:3 near resonance with Neptune is very suspicious. P9 only very weakly interacts with objects fully inside 150AU (Q<150) and objects with a<150 are largely unaffected. P9 weakly interacts with objects 150<a<250 over hundreds of millions of years. I suspect Drac may only be mentioned in the paper as a generic very well known "perpendicular orbital trajectory". -- Kheider (talk) 18:51, 9 February 2016 (UTC)
If an object falls back into the Kuiper belt it should remain under P9's influence until it comes under Neptune's influence, then Neptune might remove it from P9's influence giving it an orbit like many scattered disk objects. In its current orbit 2004_XR190 is not under eithers influence so I doubt it is what Brown was referring to. Agmartin (talk) 19:22, 9 February 2016 (UTC)
Neptune recently removing an object from P9's influence should mean perihelion around ~36AU and a semi-major axis up to ~150AU. I think such a transitioning object would still be an eccentric SDO with a large semi-major axis. -- Kheider (talk)
About Drac, I think it was mentioned because the paper announcing Drac's discovery speculated that since it would have a short lifetime there must be a significant source population of high inclination objects, which B&B had just identified. Agmartin (talk) 19:29, 9 February 2016 (UTC)

Comments from Mike Brown

Hi Wikifolk, Mike Brown here. I've never wikied before so I am unclear on the right approach to suggestions for the article, so please bear with me if this is not exactly the right way to do it.

I was curious what wikipedia would make of Planet Nine, so I was perusing the article this afternoon and I found a pretty major misunderstanding pervading the article. My statements are going to sound self-serving, because they probably are or I wouldn't bother writing, but I will back them up with references to the papers so that you can check and decide for yourselves.

The wiki article seriously misunderstands the relationship between the planetary hypothesis proposed by Trujillo and Sheppard in 2014 with the one we recently proposed. In fact, the first two sections of our paper demonstrate clearly that the T&S hypothesized planet **cannot work** (a conclusion also reached in a DPS presentation by Meg Schwamb this fall). After spending much of the introduction politely explaining why the T&S hypothesis is unlikely to be tue, we reach the key line in our paper: "the stable objects cluster not around ω = 0 but rather around ω = 318° ± 8°, grossly inconsistent with the value predicted from by the Kozai mechanism." We do not dwell on this point in the paper, because it is instantly clear what it means: there is no planet causing Lidov-Kozai librations about zero, because the argument of perihelion is not even clustered around zero. Having shown that it cannot work, we then completely discard the T&S hypothesis and search for a new one. Again, from the paper, "Much like confinement in ω, orbital alignment in physical space is difficult to explain because of differential precession. In contrast to clustering in ω, however, orbital confinement in physical space cannot be maintained by either the Kozai effect or the inclination instability. This physical alignment requires a new explanation."

We find that a massive eccentric inclined object captures bodies into mean motion resonances and aligns them in physical space, not in argument-of-perihelion space. The alignment in argument is a mundane consequence of the real physical alignment.

What IS true is that T&S were the first to show that there was clustering and that something needed to be explained. They even speculated that it might be a planet, but they provided no evidence that a planet could do what they wanted it to do (because it couldn't). In the wiki article, that falls more under the "Early Speculation" realm than the "Case for a New Planet" realm. And it is certainly inaccurate to say:

"The strongest argument for the existence of Planet Nine was published in 2014, by astronomers Scott Sheppard of the Carnegie Institution of Science and Chad Trujillo of Hawaii's Gemini Observatory, who suggested the similar orbits of certain objects such as sednoids might be influenced by a massive unknown planet at the edge of the Solar System.[4] Their findings suggest that a super-Earth of about two to 15 Earth masses beyond 200 AU with a highly inclined orbit at 1500 AU could shepherd the extreme trans-Neptunian objects into similar orbits."

They published interesting speculations, but their specific findings have been shown to be wrong, so not only was it not the strongest argument for Planet Nine, it was an incorrect argument for something entirely different!

When I discuss this in the press, for example, I try very hard to give them the appropriate credit, which is that they were the first to really show hints that there were things in the outer solar system that needed explaining, and they even speculated that it might be a planet. But they couldn't figure out how a planet would really cause the effects they were seeing. The closest historical analogy is to Anders Johan Lexell in 1781 calculating the orbit of Uranus for the first time and realizing that there must be a planet out there perturbing it. But he certainly didn't know how to calculate its orbit or its mass or anything else about it. That took until 1846 when le Verrier and/or Adams figured out the math and the physics to make it work.

Sorry for the long rant. I feel a little sordid even writing this and would normally not sweat the inevitable inaccuracies, but this one just seemed odd and so wrong that I thought it was worth pointing it out.

Please feel free to ignore me, but do please go reread the original sources and decide for yourselves what you think is the right way to explain this.

Mike Brown (Michael E. Brown, research author) February 4, 2016 (131.215.64.52)

Thanks Mike! I've not been involved in writing the article itself, but I'm sure the editors involved will help get these facts corrected. Tom Ruen (talk) 02:57, 5 February 2016 (UTC)
Thanks for the feedback Mike. I'll flag the section for accuracy while people review your comments. Headbomb {talk / contribs / physics / books} 03:12, 5 February 2016 (UTC)
Mike, thank you so much for writing this. Never hesitate to provide your thoughts on these article talk pages...we highly encourage feedback from experts. Hopefully we can get this issue rectified. — Huntster (t @ c) 05:38, 5 February 2016 (UTC)

I've done an initial cleanup. Others may feel it requires more. Serendipodous 07:44, 5 February 2016 (UTC)

I've also done some cleanup. --JorisvS (talk) 11:25, 5 February 2016 (UTC)
I've added statements on work by Carlos and Raul de la Fuente Marcos. seemed similar to (& a furthering of) Trujillo & Sheppard J mareeswaran (talk) 14:26, 5 February 2016 (UTC)

Trying to understand the difference - How does the Kozai mechanism itself force a result of 0° or 180° (and if it must shouldn't the wikipedia article say so instead of 90° and 270° - I think, don't know but I think, this angle is measured relative to the outer purturber at least in one case and or that of celestial orientation in the other or does it just fall out assuming a certain pattern of purtubers?)? As I read it, it is a 3 body perturbation and it seems to me that some angle must come out the calculation but not why a particular orientation in the solar system must fall out of it or why it would be strongest in the early solar system and not later. Yes - I think the T&S paper has an qualified relationship with the Kozai affect. On the one hand they say

"The Lidov–Kozai effect is the best known dynamical mechanism for constraining the ω of a minor planet. This three-body interaction can create outer Oort cloud objects with ω preferentially near 0° and 180° early in the history of the Solar System when the Sun was still among its nascent cohort of perturbing stars. This cannot explain the ω ~ 0° trend today, because ω circulates owing to the presence of the giant planets. By numerically simulating the effect of the known mass in the Solar System on the inner Oort cloud objects, we confirmed that inner Oort cloud objects should have random ω (Methods). This suggests that a massive outer Solar System perturber may exist and restricts ω for the inner Oort cloud objects."
and later say "To test the massive perturber hypothesis as a source in constraining ω, we ran several simulations with a single body of 2–15 Earth masses in a circular low inclination orbit between 200 AU and 300 AU using the Mercury integrator. In general it was found that the ω for the inner Oort cloud objects 2012 VP113 and Sedna routinely librated with an amplitude of about ±60° around ω = 0° for billions of years. The librating behaviour of ω for 2012 VP113 with an additional body of 5 Earth masses at 210 AU is illustrated in Extended Data Fig. 3, where 2012 VP113 spends only 3% of its time in the 90° < ω < 270° region. Sedna spent 1% of its time in this region. For the low-i super-Earth simulations, the lower-perihelion objects did not librate for long periods as did 2012 VP113 and Sedna and spent 30% to 50% of their time with 90°< ω < 270°. We also ran simulations with highly inclined Neptune mass bodies at about 1,500 AU and found most objects exhibiting short ω librations, which suggests some interesting potential future simulation prospects." Note in this they don't say what the mechanism is but their discussion in extended figure 3 does say "Many possible distant planetary bodies can produce the pictured Kozai resonance behaviour, but the currently known Solar System bodies cannot."

So yes I pick up that they are using the Kozai affect in trying to explain an observation on a set of objects >150 AU semi major axis with an affect on ω ~ 0°. And yes I can see that B&B say "This physical alignment requires a new explanation." when focused on a two sets of objects (the 6 and the 5 especially that orient more than just ω, but the ω in this case centers on 318° for set 6.)

Out of this I do get that the two teams used different approaches to perturbation to cause alignments or orbits - but not so much that the predictions are highly distinct. T&S certainly said highly inclined Neptune class objects at 1500 AU "suggests some interesting potential future simulation prospects." While the affect may be different(?) the predictions have an overlap. Does this mean they are DIFFERENT THEORIES? I don't see the B&B article proposing a different mechanism as much as a broader use of perturbations that by its nature must include the Kozai affect? Am I reading this right? Does that still mean they are different theories?--Smkolins (talk) 14:57, 5 February 2016 (UTC)

[again, excuse my ignorance of protocol on comments here, but I think this is the right way to answer] Yes, these are entirely different theories. The objects in the aligned cluster (and the ones investigated by T&S) are not aligned by the Kozai mechanism AT ALL. The simulations by T&S do not reproduce their own observations AT ALL. Because their simulations don't work, they speculate that perhaps something else might work, but this is purely speculation. It was important speculation, and it helped lead to the correct [at least I hope so] answer, but it was just speculation. Sort of like noticing that an apple falls from a tree and thinking that it means there are goblins pushing it but then noticing that the goblin theory can't explain much and speculating that maybe some other force is involved. Ok. That's not a great analogy. But you get the point, I think. -- Mike Brown, 5 February 2016
Indeed i read "As a result, additional perturbations (i.e., harmonic terms in the Hamiltonian) are required to explain the data." (top of page 4, B&B article) --Smkolins (talk) 15:10, 5 February 2016 (UTC)
however per below then I see "Finally, the Hamiltonian (4) does not account for possibly relevant resonant (and/or short-periodic) interactions with the perturber. Accordingly, the obtained results beg to be re-evaluated within the framework of a more comprehensive model." bottom of page 4 - and then they drop al of formal theory and turn to numerical simulations. So yes, but no.--Smkolins (talk) 15:35, 5 February 2016 (UTC)
Yes! The Hamiltonian cannot account for the mean-motion resonances, which are the key physics of what is happening. So the numerical simulations are the "more comprehensive model." -- Mike Brown, 5 February 2016
  • Question: if the 6 minor planets are synchonized by mean motion resonance, that means their periods ought to be simple ratios of the hypothetical driver 9th planet? And does that mean if we can get their periods computed with higher precision, then we can estimate a best fit period for the 9th planet? (i.e. a smaller error than 10,000 to 20,000 years!) Tom Ruen (talk) 15:21, 5 February 2016 (UTC)
Yes, but no. The periods are ratios, but not necessarily simple small number ratios. They could be crazy things like 32:27. There are currently a nearly infinite number of possibilities. But we're working on it.... --- Mike Brown, 5 February 2016
Yeah I picked up on that now on page 6 of B&B paper on left - "phase protection mechanism…Accordingly, we hypothesize that the new features observed within the numerically computed phase-space portraits arise due to resonant coupling with the perturber, and the narrowness of the stable region is indicative of the resonance width." So this is the mechanism driving populations 5 and 6? --Smkolins (talk) 15:24, 5 February 2016 (UTC)
There is; coming out in our next paper. Due soon -- Mike Brown, 5 February 2016
  • I still find the phrasing the our computer simulations, "originally developed to refute the existence of a trans-Neptunian planet, instead provided further evidence for one" awkward. Our **analysis** set out to show that a planet could not induce Kozai oscillations to cause the effects T&S had seen. We showed that and also found that it was the other, previously unnoticed orbital alignment that was, in fact significant. Our computer simulations were undertaken to understand this previously unknown alignment. Sorry for what sounds like nit picking, but as someone very interested in the process of science and having it explained correctly, I would love to have it told right here. Again, I would point you to the actual paper, which is pretty clear on this, I think. -- Mike Brown, 5 February 2015

Hi Mike, I tried to improve the language so let me know if the current one works. One question I do have that I could never find being discussed in any paper is how could so much mass be located on an orbit with such a huge inclination. A planetary disk is essentially always planar, so having a 1/2 Neptune swing at 30° is at least strange to me. Nothing of P9's size comes even close to this value. Is is something of a "counterweight" to the 1° and 2° inclinations of Jupiter and Saturn? Nergaal (talk) 18:15, 5 February 2016 (UTC)

Ejection by Jupiter will give a pretty wide range of inclinations, so ~30 degrees seems reasonable to us. I suspect that people are working on simulations to see how well the details work, though we are not looking into that part of the story yet. -- Mike Brown, 5 February 2015 — Preceding unsigned comment added by 131.215.64.52 (talk) 18:47, 5 February 2016 (UTC)
30 degrees is a "mild" inclination for an isolated object that is detached from the known 8 planets. -- Kheider (talk) 19:07, 5 February 2016 (UTC)
Thanks for the explanation. Ah, and if your predictions ever prove to correct, consider the name "Hades" (sent to the underworld by his brother Jupiter). Nergaal (talk) 19:43, 5 February 2016 (UTC)
Unfortunately for that, the Greek god Hades is "equivalent" to the Roman Pluto. (And Jupiter is also a Roman name.) --Ørjan (talk) 04:16, 6 February 2016 (UTC)

Kozai vs Mean-motion

To be able to discount the Kozai mechanism based on a required angle that does not fit the data, the angle has to be absolute, not relative to the planet. After all, the planet's orbit is unknown, and therefore the planet's argument is a priori undetermined. Hence, if relative, any angle could fit the data. In all, it is still unclear why the Kozai mechanism requires an absolute angle of 0° or 180°. --JorisvS (talk) 20:48, 9 February 2016 (UTC)

  • Kozai was discounted for any existing or hypothetical planet on ecliptic plane because the 6 stable distant objects dont cluster at 0°/180°
  • Kozai for hypothetical planet was considered unlikely by Brown (see note E ) because it requires multiple planets finely tuned to match observed orbits of distant objects
  • So B&B abandoned theoretical perturbation models & went for a complete numerical simulation based model for a single object/perturber 10M in the plane 30° and it turned out that mean-motion resonance mechanism could produce the observed effect
best is to read the summary of the paper which links back to each section of the paper J mareeswaran (talk) 10:04, 10 February 2016 (UTC)
when I have the time, I will try to quote the summary and how it ties in with the details in the paper. that might help J mareeswaran (talk) 10:07, 10 February 2016 (UTC)
"unclear why the Kozai mechanism requires an absolute angle of 0° or 180°" The argument of perihelion (ω) is the angle between the ascending node (Ω) and longitude of perihelion (omega bar) which is also known as longitude of periapsis. We can determine the position of the ascending node and longitude of perihelion (the position of perihelion) of the objects from their orbits and calculate their arguments of perihelion. There is no need to know the orbit of Planet Nine to make this determination. Agmartin (talk) 18:11, 10 February 2016 (UTC)
Of course we can know their ω. The point is why we can discount the Kozai mechanism based on knowing only ω of these minor planets and not that of Planet Nine. --JorisvS (talk) 18:22, 10 February 2016 (UTC)
The Kozai mechanism Trujillo and Sheppard are using for their hypothesis depends on the arguments of perihelion of the objects only. It is independent of the argument of perihelion of Planet Nine. The mechanism of B&B is different in that it predicts an alignment of both the longitude of the ascending node and longitude of perihelion which allows them to predict the argument of perihelion of Planet Nine. Agmartin (talk) 18:34, 10 February 2016 (UTC)
That much is obvious. Otherwise the Kozai mechanism could not have been discounted. But why is this the case? What is the logic behind it? --JorisvS (talk) 18:50, 10 February 2016 (UTC)
I think I have the reason now, the object Trujillo and Sheppard were predicting was to be on a circular orbit. So where its argument of perihelion is has no effect. Their version of the Kozai mechanism with the 0° or 180° depends on the objects having perihelia inside the added planet and aphelia outside. The detached objects have very eccentric orbits so it probably could have a modest eccentricity without affecting the alignments of their orbits so the planet's argument of perihelion would still have no effect. Agmartin (talk) 19:40, 10 February 2016 (UTC)
And if I try to visualize this with larger eccentricities I believe if the eccentricity of the planet is large there needs to be either alignment of the longitudes of perihelion like the secular mechanism described in B&B (for which there area as yet no objects found) or anti-alignment like the known objects. Agmartin (talk) 19:47, 10 February 2016 (UTC)
But how that align these objects if 'where its argument of perihelion is has no effect'? --JorisvS (talk) 21:04, 10 February 2016 (UTC)
Try looking at it this way, when viewed from the planet, Trujillo and Sheppard's Kozai resonance with an argument of perihelion of 0° makes the path of the object appears to be spiraling around the path of the planet's orbit, keeping it from getting too close. This works when the eccentricity of the planet is small relative to the objects. I wouldn't be surprised if there are some Jupiter trojans that do this. Agmartin (talk) 22:28, 10 February 2016 (UTC)I
If the argument of perihelion drifts away from 0° the point where the planet is the farthest inside shifts up or down and it then looks like it is following a tilted ellipse around the orbit. (I think) Agmartin (talk) 22:46, 10 February 2016 (UTC)
And if it reaches 90° the perihelion occurs at the same time as it reaches the highest point above the plane of the planets orbit, and the reverse for aphelion. Then the path it follows relative to the orbit would be a line through the orbit. So if I have this right the argument of perihelion defines the shape of the path around the orbit and how close it gets to the planet. Agmartin (talk) 00:42, 11 February 2016 (UTC)
I may have confused the issue bringing up what happens for eccentric orbits, the stability of those is from other mechanisms. Agmartin (talk) 22:36, 10 February 2016 (UTC)
It sounds much like a quasi-satellite principle, and that's a relative thing. That requires (a relative) angle of σ = Δλ = Δ(Ω + ω + M) = 0.[49] In the low-eccentricity-planet case that makes not much difference, but it does for a planet with an eccentric orbit. --JorisvS (talk) 23:40, 10 February 2016 (UTC)
Yes, the close ratio of semi-major axis did bring that to mind, or something in a horseshoe orbit. Agmartin (talk) 01:10, 11 February 2016 (UTC)

Drac

When the centaurs with elongated perpendicular orbits encounter a giant planet they evolve onto orbits like Drac's — Preceding unsigned comment added by Agmartin (talk • contribs)

Yeap - that's worth adding as another prediction/observation match. --Smkolins (talk) 12:14, 13 February 2016 (UTC)
Perhaps instead of as a separate prediction it should be mentioned at the end of the high inclination object prediction? Agmartin (talk) 22:05, 14 February 2016 (UTC)
No, I think it stands as it's own prediction/finding, just that it was published so far on their blog (though I expect it'll be in the forthcoming paper too.) Perhaps something along the lines of "While the original paper mentions Drac, it was B&B's professional blog findingplanetnine.com that spelled out their interest in Drac when Michael Brown said that it fit a category of objects… …(go into the specifics of the class of objects and that they fit the models/details.) --Smkolins (talk) 23:08, 14 February 2016 (UTC)

Nice model

This blog post by Sean Raymond explains why Planet Nine is unlikely to have been the fifth planet ejected in recent versions of the Nice model for those interested. Agmartin (talk) 21:30, 16 February 2016 (UTC)

any idea what is the NICE-2 model & when was it formulated? I can't see any reference to NICE-2 outside of wikipedia J mareeswaran (talk) 12:52, 17 February 2016 (UTC)
Nice-2 is from this article where they included the interactions between planetesimals and discovered the instability could be triggered even when the planetesimals don't cross the orbits of the planets. The only place I've seen it mentioned is in other journal articles discussing Nice model simulations but its not often mentioned by that name. Instead what is written is something like 'for simulations with the planetesimal disk more than 2 AU beyond the outer planet we shifted the inner ice giant 180 degrees around its orbit to trigger the instability' which means they approximated Nice-2 to same computer time. A couple of years ago it was shown to reduce the impacts on the inner satellites of Saturn enough to prevent all of their ice from being vaporized pdf of poster, and mentioned by name for once. Agmartin (talk) 16:43, 17 February 2016 (UTC)
In simpler terms, the Nice-2 model is a different staring configuration, the planets begin in resonance instead of moving toward one, and a different way to kick off the instability. After that starts the planets do pretty the same things as in the original version. Agmartin (talk) 01:46, 18 February 2016 (UTC)
So as I understand from the pdf image there are 3 models (as per Hal Levison) - to explain Kuiper Belt
  • (1) Original NICE model - created in 2005 ( by Morbidelli/Gomes et al )
  • (2) modification to NICE ( kuiper belt outside giant planets ) - termed as NICE 2 in 2011 ( by Hal Levison et al)
  • (3) fifth giant planet (another modification to original NICE) - also in 2011 (by Nesvorny in 2011, supported by Batygin & Morbidelli in later papers)
  • and then there is a Grand Tack model (2012 by Sean Raymond & Morbidelli) to explain terrestrial planets & asteroid belt (but doesn't explain kuiper belt I think)
so there are 2 valid NICE based models (1) NICE-2 by Levison & (2) NICE+5th_Giant_planet by Batygin/Morbidelli/Nesvorny plus a Grand Tack model by Sean Raymond (& also Morbidelli)
both Batygin, a supporter of NICE-1 based 5th giant plant model & Sean Raymond of Grand Tack model think that Planet 9 must have been ejected much earlier in the solar-system's evolution & Raymond seems to suggest that the Mass & composition of Planet 9 will hold more clues to its formation. did I get it right? J mareeswaran (talk) 12:24, 18 February 2016 (UTC)
If you go historically there is
  • original Nice model, 2005.
  • the planets begin in resonance, the result of gas driven migration, ~2007.
  • an ice giant encounters both Saturn and Jupiter, driving rapid separation of Jupiter and Saturn, 2009-2010. This is needed to avoid increasing eccentricities of terrestrial planets and inclinations of asteroids. Referred to as jumping-Jupiter scenario. This was seen in some simulations of the original Nice model, but rejected at that time because that planet was lost leaving three.
  • five planet Nice model, with one ejected, 2011.
  • Nice 2, interactions between planetesimals lead to breaking of the resonance chain, 2011. Previously the timing of instability when the planets began in resonance was very sensitive to location of inner edge of planetesimal disk which some saw as requiring too much fine tuning.
I see Nice 2 as the preliminary steps to the instability, and the Grand Tack as a specific migration that ends with the planets in resonance. So it appears to me that we are left with the Grand Tack, followed by Nice 2 with either four or five planets, more likely five in my view. At least for now, you never know when someone will come up with something new. Agmartin (talk) 17:46, 18 February 2016 (UTC)
This article by Alessandro Morbidelli has most of this in one place, except the five planet version. Agmartin (talk) 17:52, 18 February 2016 (UTC)
Perhaps a summary form of this should be posted to findplanetnine.com and leveraged in place that the P9 hypothesis was crucially evolved by explaining Sedna and (x) couldn't get out that far if the perihelion was so far away from the big planets but P9 itself suffers from the same problem. Then introduce the evolving models of the solar system and conjectures about ways to develop P9. --Smkolins (talk) 13:51, 21 February 2016 (UTC)

Planet X

@Serendipodous: 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? Serendipodous 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. nagualdesign 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. Serendipodous 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. Serendipodous 05:39, 17 February 2016 (UTC)
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