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View Full Version : A mainstream take on Planet X?



Argos
2008-Feb-28, 01:42 PM
I can“t vouch for the credibitlity of this story (http://news.yahoo.com/s/afp/20080228/ts_afp/japanspaceastronomy_080228104003), but since the original article is allegedly to be published in the Astronomical Journal (http://www.journals.uchicago.edu/action/doSearch?volume=134&year=2007&issue=6&journalCode=aj&journal=aj&searchText=mukai&filter=single&x=15&y=10), and the scientist has partaken in previous planetesimal studies, I“m putting it here. Feel free to move it.


The researchers at Kobe University in western Japan said calculations using computer simulations led them to conclude it was only a matter of time before the mysterious "Planet X" was found.

A.DIM
2008-Feb-28, 01:43 PM
in the outer solar system.

According to physorg (http://www.physorg.com/news123406660.html), "The researchers at Kobe University in western Japan said calculations using computer simulations led them to conclude it was only a matter of time before the mysterious "Planet X" was found."

3488
2008-Feb-28, 02:17 PM
Wonder if a major announcement is due?

Very interesting, I hope that it is true.

Andrew Brown.

A.DIM
2008-Feb-28, 02:37 PM
I doubt it.

Their statements were, after all, based only on computer models.
While any number of astronomers have been searching for the elusive planet x to no avail, I, too, think it only a matter of time before something quite surprising is discovered in the outer system.

Sp1ke
2008-Feb-28, 02:41 PM
It sounds to me like they're looking at "planet X" as a large Kuiper Belt object, not the Planet X of woo woo culture. If so, this is mainstream - I think it is quite reasonable that there are more objects larger, and further out, than Pluto.

A.DIM
2008-Feb-28, 03:22 PM
Regardless of all the associated woo, it seems to me that planet x has been mainstream for quite some time.
Daniel Whitmire (http://www.ucs.louisiana.edu/~dpw9254/) has been publishing work on planet x for some twenty years.




Also, it appears our threads are minute apart and could be merged.

ToSeek
2008-Feb-28, 03:33 PM
Regardless of all the associated woo, it seems to me that planet x has been mainstream for quite some time.
Daniel Whitmire (http://www.ucs.louisiana.edu/~dpw9254/) has been publishing work on planet x for some twenty years.




Also, it appears our threads are minute apart and could be merged.

Done.

Trocisp
2008-Feb-28, 03:54 PM
I think clarification is required.

There's woo woo planet X (Nibiru, The Destroyer, the suns evil cousin, etc) and there's Scientific Planet X, which is just another object in the outer solar system.


Woo woo planet x does not exist. The real one might.

Ara Pacis
2008-Feb-28, 06:44 PM
Planet X is real! Scientists have ignored it and will not accept the idea. It's a conspiracy, I tell ya, a conspiracy. Planet X is...




...Eris.

Argos
2008-Feb-28, 06:52 PM
Except that they“re talking bout a real planet [not a dwarf one]. Exciting news.

01101001
2008-Feb-28, 07:42 PM
Except that they“re talking bout a real planet [not a dwarf one]. Exciting news.

Has it "cleared the neighbourhood" around its orbit?

AndreasJ
2008-Feb-28, 08:37 PM
Has it "cleared the neighbourhood" around its orbit?

Perhaps. At .3-.7 earth masses it'd be well more massive than all known transneptunians together, and at 100-175 AU out it'd be far outside the Kuiper belt.


(Tangentially, the term "classical planet" now apparently means a "real planet as opposed to a tiny iceball accidentally discovered". It used to mean naked-eye planet.)

Argos
2008-Feb-28, 08:56 PM
Has it "cleared the neighbourhood" around its orbit?

It would be interesting if it was found that it hasn“t cleared the neghborhood, but still has a .7 Earth mass... Dwarf planet? Laughable...

tracer
2008-Feb-28, 10:18 PM
Regardless of all the associated woo, it seems to me that planet x has been mainstream for quite some time.
Daniel Whitmire (http://www.ucs.louisiana.edu/~dpw9254/) has been publishing work on planet x for some twenty years.

Well, don't forget, a century ago "Planet X" referred to an undiscovered planet out beyond the orbit of Neptune, whose existence was predicted due to "perturbations in Neptune's orbit."

It turns out the so-called "perturbations" of Neptune's orbit were imaginary. Neptune's orbit matched perfectly with what you'd expect it to be with NO planet out any farther, within the experimental error of the measurements of the time.

A.DIM
2008-Feb-29, 04:49 PM
Well, don't forget, a century ago "Planet X" referred to an undiscovered planet out beyond the orbit of Neptune, whose existence was predicted due to "perturbations in Neptune's orbit."

It turns out the so-called "perturbations" of Neptune's orbit were imaginary. Neptune's orbit matched perfectly with what you'd expect it to be with NO planet out any farther, within the experimental error of the measurements of the time.


Hi tracer.

Indeed, the alleged perturbations in the orbits of Uranus and Neptune as a basis for predicting the presence of another planet disappeared with Standish Jr's paper in '93.
Curiously though, or coincidentally, Pluto was discovered right where the imaginary perturbations predicted.
No matter really, as other observations have been made and are used as a basis for predicting the presence of planet x (eg. cometary wake, Kuiper cliff, Sedna, CR105 etc.).

I only pointed to Whitmire sine Argos seemed to question credibility and rely on published work as determining the mainstream.


Regards

Launch window
2008-Feb-29, 04:50 PM
interesting story, but I'm not sure of any new object found beyond Neptune would fit our new classification of a planet

A.DIM
2008-Feb-29, 05:08 PM
I suspect many dwarf planets will also be found but it's been called everything from a massive body to neptune-sized to brown dwarf.

We need to find it first.

Trocisp
2008-Feb-29, 05:46 PM
I'm both petrified and extremely interested in the possibility of a Brown Dwarf in our outer solar system.

Petrified, because that means that there's a remote possibility of the woowoo theory about a brown dwarf sending outer-solar system objects in that could smash into earth.

Interested because I really want to gather information about brown dwarfs, even if it's only a very small amount (for now).

Ara Pacis
2008-Feb-29, 06:26 PM
Except that they“re talking bout a real planet [not a dwarf one]. Exciting news.

Good point. We have three dwarf planets, so maybe instead of Planet X, we have Planets XXX. Hmmm, that would be funnier if the last one was called Eros instead of Eris.

A.DIM
2008-Feb-29, 06:49 PM
I'm both petrified and extremely interested in the possibility of a Brown Dwarf in our outer solar system.

Petrified, because that means that there's a remote possibility of the woowoo theory about a brown dwarf sending outer-solar system objects in that could smash into earth.

Interested because I really want to gather information about brown dwarfs, even if it's only a very small amount (for now).

It seems what we know suffers from selection effects, but so far many brown dwarfs appear in binary systems. And given the prevalence of binary star systems, coupled with the various observations suggestive of a planet x, I'm inclined to think ours too may be part of such a system.

Nothing to be petrified over though, after all, there's already more than a remote possibility that things will smash into earth.

spacestart.eu
2008-Feb-29, 07:04 PM
Like said before, this planet has nothing to do with Niburu this is a different object. The orbit of planetX is 1000 years Niburu is assumed to have an orbit of 3600 years according to ancient writings.

A.DIM
2008-Feb-29, 07:12 PM
Indeed.
And there's a "Niburu" (sic) thread in CT, if you like.
Although, your remark on the sumerian SAR of 3600yrs as being the orbital period of Nibiru is quite specifically an ATM concept and might do better there instead.


Regards

Van Rijn
2008-Feb-29, 10:57 PM
I'm both petrified and extremely interested in the possibility of a Brown Dwarf in our outer solar system.


The Kobe claim is suggesting an object of .3-.7 of the mass of the Earth. A Brown Dwarf is generally considered to be an object of at least 13 times the mass of Jupiter, or over 4,000 times the mass of the Earth.

A brown dwarf would have to be very far from the sun indeed to have not been detected already.

Noclevername
2008-Feb-29, 10:59 PM
There's a lot of mass in the outer Solar System, maybe some cluster of lesser KBOs is just lined up right to make the same gravitational effects as a planet.

AndreasJ
2008-Feb-29, 11:36 PM
There's a lot of mass in the outer Solar System, maybe some cluster of lesser KBOs is just lined up right to make the same gravitational effects as a planet.
Are you assuming that they're basing this on orbital anomalies (ą la how Neptune was predicted and discovered)? I don't believe that's the case. Look at this excerpt from the article:

The researchers set up a theoretical model looking at how the remote area of the solar system would have evolved over the past four billion years.

"In coming up with an explanation for the celestial bodies, we thought it would be most natural to assume the existence of a yet unknown planet," Mukai said.
Apparently, they're undaunted by the failures of such dynamical models in predicting extrasolar systems ...


In any case, I'd think it fairly easy to tell the gravitational effect of a conjunction of KBOs from that of a planet 2-4 times as far out - measuring the effect on several bodies would allow you to triangulate the location of the disturber, and you wouldn't need much resolution to tell those two cases apart.

Byrd
2008-Mar-01, 01:33 AM
I'm both petrified and extremely interested in the possibility of a Brown Dwarf in our outer solar system.


As I understand it, we'd have seen it by now. Since they're stars, they glow and that makes them kinda findable (as opposed to non-glowing planets)

A.DIM
2008-Mar-01, 02:37 AM
As I understand it, they're still searching the half billion point sources in the 2mass data for such an object while IRAS too may have detected it but because it's proper motion isn't known we wouldn't know.
Then again the optimum wavelength is said to be 5 microns for brown dwarfs which is what WISE is designed for. Until WISE, no other searches were at this wavelength.

I don't think we'd have seen it by now, but if such an object exists, WISE should find it.

Van Rijn
2008-Mar-01, 08:13 AM
As I understand it, we'd have seen it by now. Since they're stars, they glow and that makes them kinda findable (as opposed to non-glowing planets)

A brown dwarf can't be ruled out, but there are some pretty heavy constraints on how close one could be, because we haven't seen one, and the lack of gravitational effects. For instance, from:

http://arxiv.org/abs/astro-ph/?0506548

No evidence for non-zero acceleration has been found; the typical sensitivity achieved by our method is a/c=a few times 10^{-19} s^{-1}, comparable to the acceleration due to a Jupiter-mass planet at 200 AU.

A brown dwarf would be much more massive, so would have to be further out yet.

laurele
2008-Mar-02, 03:16 AM
interesting story, but I'm not sure of any new object found beyond Neptune would fit our new classification of a planet

Discovery of a large object beyond Neptune would likely hasten revision of the "new classification." It would be very hard to justify calling a Mars-sized object in the Kuiper Belt a "dwarf planet" while calling Mars in its current orbit a full-fledged planet. This is part of the inherent problem with the IAU's classification system, in that one can have two objects of the same size, with one being called a planet and the other not a planet simply because of where they are located.

Tim Thompson
2008-Mar-04, 05:29 PM
There is no direct, dynamical evidence from the inner solar system (i.e., Sun to Pluto) for any planet sized object beyond Pluto (Standish, 1993 (http://adsabs.harvard.edu/abs/1993AJ....105.2000S)). All of the arguments I have seen in support of the idea are based on statistical modeling of the Kuiper Belt dynamics, or on statistical modeling of long period comet orbits. It appears that Lykawka & Mukai, 2007a (http://adsabs.harvard.edu/abs/2007arXiv0712.2198S) is a preprint for the paper to appear in the Astronomical Journal. It is a statistical analysis of Kuiper Belt dynamics (see also Lykawka & Mukai, 2007b (http://adsabs.harvard.edu/abs/2007Icar..189..213L) and Lykawka & Mukai, 2007c (http://adsabs.harvard.edu/abs/2007Icar..186..331L), which establish the basis of the study in 2007a). There have been many studies like this which are perhaps indicative of the probability of another roughly Earth mass object in the outer solar system, or even a brown dwarf far out in the Oort cloud (i.e., Matese, Whitman & Whitmire, 1999 (http://adsabs.harvard.edu/abs/1999Icar..141..354M) proposes a few Jupiter mass brown dwarf about 25,000 AU out), but none of it is either strong or convincing, as far as I am concerned.

Ara Pacis
2008-Mar-04, 09:45 PM
There is no direct, dynamical evidence from the inner solar system (i.e., Sun to Pluto) for any planet sized object beyond Pluto (Standish, 1993 (http://adsabs.harvard.edu/abs/1993AJ....105.2000S)).

You're aware, are you not, that this citation argues against you. Based on the assumptions implicit in the citation, the author was clearly wrong. Since Pluto was included as a planet at the time, Eris should be considered the tenth planet in that argument.

laurele
2008-Mar-04, 10:01 PM
You're aware, are you not, that this citation argues against you. Based on the assumptions implicit in the citation, the author was clearly wrong. Since Pluto was included as a planet at the time, Eris should be considered the tenth planet in that argument.

Eris should still be considered the tenth planet (or the eleventh, if we count Ceres).

Tim Thompson
2008-Mar-05, 05:03 PM
You're aware, are you not, that this citation argues against you.
The paper appeared in The Astronomical Journal (http://www.iop.org/EJ/journal/aj), a journal of the American Astronomical Society (http://www.aas.org/), in The United States of America (https://www.cia.gov/library/publications/the-world-factbook/geos/us.html), in 1993 (http://en.wikipedia.org/wiki/1993). In this country, Ex Post Facto laws (http://www.law.cornell.edu/wex/index.php/Ex_post_facto) are unconstitutional (Article I (http://www.law.cornell.edu/constitution/constitution.articlei.html), sections 9 & 10). Therefore, since Pluto (http://www.nineplanets.org/pluto.html) was recognized as a planet (http://en.wikipedia.org/wiki/Planet) in 1993 throughout the U.S., it cannot now be considered to have not been a planet in 1993 by Ex Post Facto judgment (American English (http://en.wikipedia.org/wiki/American_English)), even if that should contradict the cruel & unusual judgements (British English (http://en.wikipedia.org/wiki/British_English)) of the IAU (http://www.iau.org/). Case Dismissed.

Ara Pacis
2008-Mar-05, 08:10 PM
The paper appeared in The Astronomical Journal (http://www.iop.org/EJ/journal/aj), a journal of the American Astronomical Society (http://www.aas.org/), in The United States of America (https://www.cia.gov/library/publications/the-world-factbook/geos/us.html), in 1993 (http://en.wikipedia.org/wiki/1993). In this country, Ex Post Facto laws (http://www.law.cornell.edu/wex/index.php/Ex_post_facto) are unconstitutional (Article I (http://www.law.cornell.edu/constitution/constitution.articlei.html), sections 9 & 10). Therefore, since Pluto (http://www.nineplanets.org/pluto.html) was recognized as a planet (http://en.wikipedia.org/wiki/Planet) in 1993 throughout the U.S., it cannot now be considered to have not been a planet in 1993 by Ex Post Facto judgment (American English (http://en.wikipedia.org/wiki/American_English)), even if that should contradict the cruel & unusual judgements (British English (http://en.wikipedia.org/wiki/British_English)) of the IAU (http://www.iau.org/). Case Dismissed.

Hehehe, you misunderstood. I'm not saying he's wrong because Pluto was not a planet at the time, He's wrong because it was, an assumption would would have included Eris, a tenth planet candidate, at the time had it been known. But I'll give him credit where credit is due; there was no real evidence of a tenth planet in the ephemerides, nevertheless one was there. His theory was correct, but was still wrong on the final judgement.