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Caltech Researchers Find Evidence of a Planet Beyond Pluto

caltech.edu

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Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#121

Post by [deleted] »

gaur wrote: post #98
tdaltonc wrote: post #25

> Batygin and Brown inferred its presence from the peculiar clustering of six previously known objects that orbit beyond Neptune. This raised a big red flag in my mind. This must produce a literally astronomical multiple comparisons problem. Yes they reported sigma = 3.8, but if they didn't do their multiple comparisons correction right (which I am in no position to determine), they're basically reading tea leaves. I…

> but if they didn't do their multiple comparisons correction right (which I am in no position to determine), they're basically reading tea leaves. Please don't spread FUD about other people's research and then try to soften it with a disclaimer about how you're "in no position to determine" anything about the research. If you want to offer criticism of the research, you should do the legwork to find out what the res…

[deleted]

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#122

Post by axxl »

At WWDC last year one of the lunchtime presentations was by Michael Brown, one of the researchers involved here. He was one of the people who proved that Pluto should not be considered a planet and went over the history of the discovery/classification of planet bodies. He also mentioned that they had some evidence of a planet body beyond Pluto due to its gravitational affect of some of the smaller bodies out there even then. Interesting to see this is finally coming to something! He has the appropriate/amusing twitter handle of http://twitter.com/plutokiller

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#123

Post by InclinedPlane »

beamatronic wrote: post #2

Why wouldn't their calculations be able to suggest possible locations for the planet?

They do, but there are two problems. One is that that still leaves a pretty big range for possibilities for where the planet could be. The other is that we don't know where along the orbit the planet is now. Even if we knew the exact orbit of the planet simply not knowing where it was along that orbit means we'd have to scan a lot of the sky to spot it. Having a bit more ambiguity about the orbital parameters means we will have to scan much, much more of the sky to spot it.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#125

Post by purpled_haze »

hackuser wrote: post #48

The NY Times covers the story well: http://www.nytimes.com/2016/01/21/science/space/ninth-planet... EDIT: After reading the comments in this discussion, many of which are addressed in the NYT article, I'd say the NYT article is almost certainly worth reading.

I just wished they hadn't indicated this new planet is the "ninth planet". Dwarf planets are no less planets than little people are people.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#127

Post by roborodent »

purpled_haze wrote: post #125
hackuser wrote: post #48

The NY Times covers the story well: http://www.nytimes.com/2016/01/21/science/space/ninth-planet... EDIT: After reading the comments in this discussion, many of which are addressed in the NYT article, I'd say the NYT article is almost certainly worth reading.

I just wished they hadn't indicated this new planet is the "ninth planet". Dwarf planets are no less planets than little people are people.

The video I saw from Caltech suggested a mass of 1-10 times Earth's.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#128

Post by mutagen »

xenophonf wrote: post #105

No one's mentioned Tyche yet? https://en.wikipedia.org/wiki/Tyche_%28hypothetical_planet%2... In searching for Tyche, the WISE missions ruled out the possibility of anything larger than Saturn (95x the mass of Earth) out to about 10000 AU and anything larger than Jupiter (317x the mass of Earth) out to about 26000 AU. WISE was able to detect objects the size of Neptune (17x the mass of Earth) out to about 700 AU, so…

Their site at http://www.findplanetnine.com/p/blog-page.html addresses the areas the Tyche survey and other surveys cover.

My TLDR:

* The WISE survey might only find Planet X at it's nearest approach. Kevin Luhman has redone the survey using the most sensitive WISE bands that only cover a narrow area of the sky and hasn't found Planet X.

* They reviewed the Catalina Sky Survey and eliminated most of the areas they'd expect Planet X.

* The Pan STARRS site survey didn't find Planet X.

Conclusion: Planet X is at aphelion, difficult to find with the Milky Way as a (stunning) backdrop.

I just found their paper: http://iopscience.iop.org/article/10.3847/0004-6256/151/2/22

I wonder how their conclusions match with David Nesvorny's paper predicting a 5th planet having been ejected from the Solar System: http://arxiv.org/pdf/1109.2949v1.pdf

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#130

Post by purpled_haze »

roborodent wrote: post #127
purpled_haze wrote: post #125

Earlier quoted context omitted.

I just wished they hadn't indicated this new planet is the "ninth planet". Dwarf planets are no less planets than little people are people.

The video I saw from Caltech suggested a mass of 1-10 times Earth's.

You misunderstood. I was saying that this new planet is not the 9th planet if you include dwarf planets as "planets".
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