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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

#151

Post by jharohit »

dr_zoidberg wrote: post #145
jharohit wrote: post #141

Now only if they name the ninth planet starting with a 'P', my childhood mnemonic "My Very Educated Mother Just Served Us Nine Pizzas" would finally be complete again! :D My suggestion is 'Prometheus' - sounds tragic and bad ass at the same time!

Well that would be consistent with the roman/greek names for planets and large moons. Now we have to find a stronger tie between the theory and the myth. In some article regarding this news I've read that Planet 9 might have ended in its orbit due to encounters with Jupiter/Saturn. Not exactly an eagle eating its liver, but it can be paralled to "the punishment from Zeus(Jupiter)".

:) well nicely connected with the punishment story! I would further go and say that we can draw parallels with the Kuiper Belt objects to the eagles "tormenting" Prometheus while he is chained to a "cold, lonely mountain rock" like our new mysterious planet stuck in a dark lonely corner of the solar system!

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#152

Post by jerf »

XorNot wrote: post #108
jerf wrote: post #83

Earlier quoted context omitted.

I'd also observe that in terms of prior probability, "There is a ninth planet in the solar system that we have not yet detected" is probably hovering at least in the low-integer percentages, and I imagine some scientists would place it higher than that. The general idea is not a wild, far-out one by any stretch of the imagination.

That isn't how probability works though. You have a Bayesian priors problem - you can't establish what the initial probabilities are.

I can put some bounds on them, which is all I tried to do. It is certainly not reasonable to act as if the idea there is a ninth undetected planet is some sort of one-in-a-trillion possibility.

I'm not even convinced you're correct anyhow; since I tend to accept the interpretation of probability as a statement of our knowledge of the world as good enough most of the time, we can establish a reasonable probability statement that expresses that uncertainty. We don't know everything about the universe or even our solar system but there is something about this topic that makes people start grossly overstating our ignorance.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#153

Post by xenophonf »

rplnt wrote: post #136
mutagen wrote: post #128

Earlier quoted context omitted.

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…

> Planet X is at aphelion, difficult to find with the Milky Way as a (stunning) backdrop. I would have assumed that planets are easier to detect when they have a backdrop? That the light can be blocked, partially blocked, bent, .. Isn't that the case?

You're thinking about one of the ways extrasolar planets can be detected, when they cross in front of their parent star (transit photometry) or when they're imaged using light magnified or redirected by a massive foreground object (gravitational microlensing). I don't think we have the capability to detect something in this solar system eclipsing a background object (whether that's a star or a galaxy or whatever else is out there).

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#154

Post by theptip »

ceejayoz wrote: post #41
SolarNet wrote: post #35

Earlier quoted context omitted.

Or is it perhaps the other way around. Did Kerbel use the same UI as a popular rendering program used by astronomers.

Or, third option, "there's only a few decent ways to represent orbits on a graphic".

The colour schemes are very similar though. There are many colour schemes one could choose.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#156

Post by rbanffy »

blue1 wrote: post #155
rbanffy wrote: post #45

The scales involved are astonishing. If the orbit is correct, less than one year has passed on it since the invention of writing here on Earth.

What do you mean? 700 AU it's about 4 light days.

"Planet 9" takes about 11 thousand years to go around one orbit.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#157

Post by dr_zoidberg »

jharohit wrote: post #151
dr_zoidberg wrote: post #145

Earlier quoted context omitted.

Well that would be consistent with the roman/greek names for planets and large moons. Now we have to find a stronger tie between the theory and the myth. In some article regarding this news I've read that Planet 9 might have ended in its orbit due to encounters with Jupiter/Saturn. Not exactly an eagle eating its liver, but it can be paralled to "the punishment from Zeus(Jupiter)".

:) well nicely connected with the punishment story! I would further go and say that we can draw parallels with the Kuiper Belt objects to the eagles "tormenting" Prometheus while he is chained to a "cold, lonely mountain rock" like our new mysterious planet stuck in a dark lonely corner of the solar system!

Alright, time to write to IAU with a name proposal!

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#158

Post by versteegen »

xenophonf wrote: post #153
rplnt wrote: post #136

Earlier quoted context omitted.

> Planet X is at aphelion, difficult to find with the Milky Way as a (stunning) backdrop. I would have assumed that planets are easier to detect when they have a backdrop? That the light can be blocked, partially blocked, bent, .. Isn't that the case?

You're thinking about one of the ways extrasolar planets can be detected, when they cross in front of their parent star (transit photometry) or when they're imaged using light magnified or redirected by a massive foreground object (gravitational microlensing). I don't think we have the capability to detect something in this solar system eclipsing a background object (whether that's a star or a galaxy or whatever else…

Correction, rogue planets are detected when their gravity causes micolensing of distant objects (stars), not the other way around.

https://en.wikipedia.org/wiki/Rogue_planet#Observation

Not an astronomer, but my impression is that microlensing couldn't be used to detect objects in our own solar system, but I don't see any reason why eclipsing of distant stars couldn't be used... it would be far too rare to be practical to find a planet, though.

Re: Caltech Researchers Find Evidence of a Planet Beyond Pluto

#159

Post by xenophonf »

versteegen wrote: post #158
xenophonf wrote: post #153

Earlier quoted context omitted.

You're thinking about one of the ways extrasolar planets can be detected, when they cross in front of their parent star (transit photometry) or when they're imaged using light magnified or redirected by a massive foreground object (gravitational microlensing). I don't think we have the capability to detect something in this solar system eclipsing a background object (whether that's a star or a galaxy or whatever else…

Correction, rogue planets are detected when their gravity causes micolensing of distant objects (stars), not the other way around. https://en.wikipedia.org/wiki/Rogue_planet#Observation Not an astronomer, but my impression is that microlensing couldn't be used to detect objects in our own solar system, but I don't see any reason why eclipsing of distant stars couldn't be used... it would be far too rare to be practic…

Thanks for the correction!
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