Posted on 11/13/2021 10:00:24 AM PST by SunkenCiv
I have carried out a search for Planet 9 in the IRAS data. At the distance range proposed for Planet 9, the signature would be a 60 micron unidentified IRAS point source with an associated nearby source from the IRAS Reject File of sources which received only a single hours-confirmed (HCON) detection. The confirmed source should be detected on the first two HCON passes, but not on the third, while the single HCON should be detected only on the third HCON. I have examined the unidentified sources in three IRAS 60micron catalogues: some can be identified with 2MASS galaxies, Galactic sources or as cirrus. The remaining unidentified sources have been examined with the IRSA Scanpi tool to check for the signature missing HCONs, and for association with IRAS Reject File single HCONs. No matches of interest survive. For a lower mass planet (< 5 earth masses) in the distance range 200-400 AU, we expect a pair or triplet of single HCONs with separations 2-35 arcmin. Several hundred candidate associations are found and have been examined with Scanpi. A single candidate for Planet 9 survives which satisfies the requirements for detected and non-detected HCON passes. A fitted orbit suggest a distance of 225+-15 AU and a mass of 3-5 earth masses. Dynamical simulations are needed to explore whether the candidate is consistent with existing planet ephemerides. If so, a search in an annulus of radius 2.5-4 deg centred on the 1983 position at visible and near infrared wavelengths would be worthwhile.
(Excerpt) Read more at researchgate.net ...
I have carried out a search for Planet 9 in the IRAS data. At the distance range pro-posed for Planet 9, the signature would be a 60 µm unidentified IRAS point source with an associated nearby source from the IRAS Reject File of sources which received only a single hours-confirmed (HCON) detection. The confirmed source should be detected on the first two HCON passes, but not on the third, while the single HCON should be detected only on the third HCON. I have examined the unidentified sources in three IRAS 60µm catalogues: some can be identified with 2MASS galaxies, Galactic sources or as cirrus. The remaining unidentified sources have been examined with the IRSA Scanpi tool to check for the signature missing HCONs, and for association with IRAS Reject File single HCONs. No matches of interest survive. For a lower mass planet (65ME) in the distance range 200-400 AU, we expect a pair or triplet of single HCONs with separations 2-35 arcmin. Several hundred candidate associations are found and have been examined with Scanpi. A single candidate for Planet 9 survives which satisfies the requirements for detected and non-detected HCON passes. A fitted orbit suggest a distance of 225±15 AU and a mass of 3-5 ME. Dynamical simulations are needed to explore whether the candidate is consistent with existing planet ephemerides. If so, a search in an annulus of radius 2.5−4ocentred on the 1983 position at visible and near infrared wavelengths would be worthwhile.
In the 1980s there had been a long history of interest in what would at that time have been a tenth planet, PlanetX. There appeared to be unexplained residuals in the or-bit of Neptune. Though these were much smaller than the Uranus residuals by which Le Verrier and Adams discovered Neptune, they had motivated Tombaugh‘s search for a new planet, which resulted in the discovery in 1930 of what we now know as the dwarf planet Pluto. It quickly became clear that Pluto was too small to explain the Neptune residuals and so the possibility of a tenth planet remained (see Batygin et al (2019) for a full historical account and references).In 1983, while working on the preparation of the IRASPoint Source Catalog, I undertook a systematic search for Planet X in the IRAS data. The search was unsuccessful though it did yield a detection of Comet Bowell (Walker and Rowan-Robinson 1984). Amusingly a misunderstanding of an earlier IRAS science team briefing by senior NASA personnel resulted in a press story in 1983 that IRAS had discovered Planet X (see Rowan-Robinson 2013 for full details of how this misunderstanding arose).Interest in Planet X flared up again in the late 1980s(Harrington 1988, Seidelmann and Harrington 1988, Jack-son and Killen 1988, Neuhauser and Feitzinger 1991) and the Royal Astronomical Society staged a discussion meeting in 1991 on ‘Solar System Dynamics and Planet X‘. I gave a report on my IRAS searches and concluded that I was 70%certain that Planet X did not exist. The figure of 70% re-ferred to the area of sky in which I was able to carry out my IRAS search. Reports of the meeting were given by Morrison(1992) and Crosswell (1991).Subsequently a remeasurement of the mass of Neptune eliminated the Neptune residuals (Standish 1992). The absence of deviations from the orbits of the Pioneer and Voy-ager spacecraft shows that no unknown massive solar system planet resides in the plane of the ecliptic. Luhman (2014) has used WISE data to set severe limits on Saturn or Jupiter mass objects in the solar system out to 28,000 and 82,000AU, respectively. The discovery of dozens of new dwarf planets during the past twenty years has resulted both in the redefinition of Pluto as a dwarf planet and in their potentiality as probes of possible distant massive planets in highly inclined orbits.Batygin and Brown (2016) and Brown and Batyin (2016), developing an idea of Trujillo and Sheppard (2014)
Mike Brown
@plutokiller
Fun paper out today on the search for Planet Nine using old IRAS data. Nothing too compelling, but there is one candidate that Rowan-Robinson mentions, before mostly dismissing it as unlikely-to-be real. Still, if is fun to ponder: what if it IS real?
https://twitter.com/plutokiller/status/1458038427090178052
In Britain, the search for Planet X has been described as a psychological, rather than astronomical, problem.
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"To Pluto And Far Beyond" By David H. Levy, Parade, January 15, 2006 -- We don't have a dictionary definition yet that includes all the contingencies. In the wake of the new discovery, however, the International Astronomical Union has set up a group to develop a workable definition of planet. For our part, in consultation with several experienced planetary astronomers, Parade offers this definition: A planet is a body large enough that, when it formed, it condensed under its own gravity to be shaped like a sphere. It orbits a star directly and is not a moon of another planet.
Hey, at least this video is short.
An exploration of the first candidate for the hypothesized ninth planet of the solar system.Have We Found Planet 9? | November 10, 2021 | John Michael Godier
Brown and Batygin are the point men for the current hypothetical unknown outer planet. Both do and have done presentations about the research, loads of them show up in YT vids. Batygin's in this one:
A planet has been predicted to orbit the sun with a period of 10,000 years, a mass 5x that of Earth on a highly elliptical and inclined orbit. What evidence supports the existence of such a strange object at the edge of our solar system?
Huge thanks to:
Prof. Konstantin Batygin, Caltech
Prof. David Jewitt, UCLA
I had heard about Planet 9 for a long time but I wondered what sort of evidence could support the bold claim: a planet at the very limits of our ability to detect one, so far out that its period is over 60 times that of Neptune. The planet 9 hypothesis helps explain clustering of orbits of distant Kuiper belt objects. It also explains how some of these objects have highly inclined orbits - up to 90 degrees relative to the plane of the solar system. Some are orbiting in reverse. Plus their orbits are removed from the orbit of Neptune, the logical option for a body that could have ejected them out so far. The fact that the perihelion is so far out suggests another source of gravity was essential for their peculiar orbits.Does Planet 9 Exist? | September 13, 2019 | Veritasium
Mike Brown is a narcissist hack with zero credibility.
In Britain, the search for Planet X has been described as a psychological, rather than astronomical, problem......
Yes.
I think that with today’s instrumentation, a planetary object that large would have been detected by now.
This is just what I was thinking.
Watch the video, the odds of detection using current stuff is very low.
Yeah, Brown and Batigyn love saying that. :^)
It’s interesting that Dr. Batygin in his brief recap of history did not even mention John Couch Adams, usually given at least equal credit for the prediction of Neptune along with LeVerrier (and in English-language sources maybe slightly more even though it was LeVerrier’s prediction that led directly to the actual discovery). Such was the situation back when I was teaching (I retired in 2014); since then I haven’t kept up, but I see that Wikipedia still gives Adams some credit. The complete story of Neptune’s discovery is a rather interesting study in the sociology of science. However, that would be too great a digression from the subject of the video.
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