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Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

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Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#31

Post by ryao »

gus_massa wrote: post #18
metalman wrote: post #3

we already have a 9'th planet, but due to the greatest pedantic campain of all time, pluto got demoted. Though given the current situation, ha!, that could change.....perhaps the naming commity will get noticed, and be offered a chance to do a deal, and Make Pluto A Planet Again,(MPAPA)

If you add Pluto, you must add also Eris and a few more, like 5 or more, and perhaps also Ceres. Here is a nice graphic that excludes Ceres https://en.m.wikipedia.org/wiki/Dwarf_planet#Population_of_d...

We should add those planets to the official list too. Gauss considered Ceres to be a planet and I believe him over living astronomers.

The motivation for this dwarf planet nonsense was to try to keep the official planet list small so children could memorize them with ease, but that is absurd. We do not remove countries from the map to make it easier for children to learn geography and there are over 100 of them.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#32

Post by nonethewiser »

1970-01-01 wrote: post #30
AIPedant wrote: post #11

I think “15 times further from the Sun than Pluto” is more meaningful for most readers than “700 times further from the Sun than Earth.” If it exists, it’s way way way out there.

Yes, also being 10x the mass of Earth that far out hints that it may be an interstellar object captured by the Sun.

Forgive my ignorance but how is that different than the rest of the planets?

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#33

Post by nonethewiser »

api wrote: post #21
TheOtherHobbes wrote: post #16

Earlier quoted context omitted.

I really hope it isn't true because if there's one out there, there will be others, and I'd rather not meet one in person. We don't have enough data to see whether there are unexpected instabilities in detected planetary systems. But it would be an interesting project to look for those.

They're not dangerous unless you get too close. A black hole is not a cosmic vacuum cleaner. If the Moon were suddenly transformed into a tiny black hole with the same mass, it would continue to orbit the Earth at the same distance. Ocean tides due to its gravity would continue normally. There would not be much effect except that it would no longer be visible with the naked eye and would no longer reflect the sun's l…

That is very interesting and made me realize I did think of black holes as “sucking” things in. Which I see is not the right way to think about it.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#34

Post by nonethewiser »

ryao wrote: post #31
gus_massa wrote: post #18

Earlier quoted context omitted.

If you add Pluto, you must add also Eris and a few more, like 5 or more, and perhaps also Ceres. Here is a nice graphic that excludes Ceres https://en.m.wikipedia.org/wiki/Dwarf_planet#Population_of_d...

We should add those planets to the official list too. Gauss considered Ceres to be a planet and I believe him over living astronomers. The motivation for this dwarf planet nonsense was to try to keep the official planet list small so children could memorize them with ease, but that is absurd. We do not remove countries from the map to make it easier for children to learn geography and there are over 100 of them.

I mean… there has to be more to it than that right? But im also open to being red pilled on pluto.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#35

Post by tliltocatl »

nonethewiser wrote: post #32
1970-01-01 wrote: post #30

Earlier quoted context omitted.

Yes, also being 10x the mass of Earth that far out hints that it may be an interstellar object captured by the Sun.

Forgive my ignorance but how is that different than the rest of the planets?

The rest of the planets are theorized to have condensed from the protoplanetary disk that formed the same molecular cloud the Sun did. I. e. they have formed at approximately same time as the sun and from same material, sans gravitational separation.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#36

Post by [deleted] »

nonethewiser wrote: post #32
1970-01-01 wrote: post #30

Earlier quoted context omitted.

Yes, also being 10x the mass of Earth that far out hints that it may be an interstellar object captured by the Sun.

Forgive my ignorance but how is that different than the rest of the planets?

[deleted]

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#37

Post by perihelions »

lazide wrote: post #29
randomtoast wrote: post #6

I find one theory regarding Planet 9 especially interesting, and that is that it could be a primordial black hole with a Schwarzschild radius on the order of just a few centimeters. So basically, just a golf ball-sized black hole. This would explain why we can see the gravitational effects on the other objects as described in many papers, and it would also explain at the same time why we have no direct observation of…

At the distances described, available passive light flux is so low, it could be 100% painted with white titanium dioxide paint and we’d be lucky to ever see it. It doesn’t need to be a black hole to be effectively invisible.

Indeed, it's a doubly inverse-squared law: one 1/d^2 factor for how far it is from the sun, by how much the solar flux is reduced; and one 1/d^2 factor again for how it is from Earth-based observers. 1/d^4, a quartic law.

That's the idea behind this paper (and similar ones like it): since they're looking for the planet's intrinsic emissions, from its internal heat, it's only a single inverse-square law.

With d being ~20 times Neptune's distance and ~140 times Jupiter's, these really are large factors!

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#38

Post by libraryofbabel »

nonethewiser wrote: post #32
1970-01-01 wrote: post #30

Earlier quoted context omitted.

Yes, also being 10x the mass of Earth that far out hints that it may be an interstellar object captured by the Sun.

Forgive my ignorance but how is that different than the rest of the planets?

The other planets formed from material in the same nebula (cloud of gas and dust) that collapsed to form the sun. The idea here is this planet would have been moving through the interstellar medium and just happened to pass close enough to the sun’s gravity well to get captured in a (very distant) orbit.

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#39

Post by raverbashing »

perihelions wrote: post #15

This cannot be evidence of Planet 9 (the Batygin and Brown hypothesis)—it's outright incompatible with it. https://bsky.app/profile/plutokiller.com/post/3lnqm2ymbd22r If those two spots are the same object, that object is on a high-inclination orbit; but the pattern the Planet 9 hypothesis explains is only compatible with a low-inclination object.

Nah, if it is big, and at that distance, and follows an elliptical orbit then yes it will be "Planet 9^W 8"

Re: Evidence of controversial Planet 9 uncovered in sky surveys taken 23 years apart

#40

Post by 01HNNWZ0MV43FF »

libraryofbabel wrote: post #38
nonethewiser wrote: post #32

Earlier quoted context omitted.

Forgive my ignorance but how is that different than the rest of the planets?

The other planets formed from material in the same nebula (cloud of gas and dust) that collapsed to form the sun. The idea here is this planet would have been moving through the interstellar medium and just happened to pass close enough to the sun’s gravity well to get captured in a (very distant) orbit.

Capture would be like a reverse gravitational slingshot? This planet happened to meet the sun at an angle where it lost enough energy to fall into orbit instead of slinging back out like those comets that come around on long cycles?
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