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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

#111

Post by dragonwriter »

AIPedant wrote: post #98
NikkiA wrote: post #70

Earlier quoted context omitted.

I dunno, '700 AU' gelled for me instantly, '15 times the distance to pluto' doesn't even make sense given pluto's orbit isn't anywhere near circular.

It makes even less sense for Earth because Earth's orbit is near-circular, whereas Planet 9's hypothesized orbit is highly eccentric, more so than Pluto. Most people don't know off-hand that Pluto is ~40-50AU from the sun, so 700AU is hard to conceptualize.

> Most people don't know off-hand that Pluto is ~40-50AU

~30-50AU if you are referring to the range of orbital distance.

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

#112

Post by XorNot »

bobmcnamara wrote: post #99
Qem wrote: post #84

Earlier quoted context omitted.

If it were a blackhole it wouldn't show up in IRAS and AKARI infrared maps.

Would probably be a screamer on x-ray though.

Not without an accretion disk, and why would it have one? It would've cleared it's orbit.

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

#114

Post by XorNot »

api wrote: post #41
nonethewiser wrote: post #33

Earlier quoted context omitted.

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.

It’s an object with theoretical maximum density. That’s one way to think about it. Another visualization: if you had an Earth mass black hole with a solid shell surrounding it at the same radius as the Earth’s surface is from its core, gravity atop that shell would be 1g. The actual black hole would be about the size of a marble. If you got close to it you would of course be subject to insane gravity and be “spaghett…

They're also interestingly one of the most boring: every black hole can be described by 3 numbers: mass, spin and charge.

Which is to say they are extremely high entropy.

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

#115

Post by jvm___ »

water-data-dude wrote: post #74
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.

I wanted to get a sense of what that MEANS relative to the rest of the gas giants. Apparently it’d be roughly the size of Uranus or Neptune. I guess I’d always put all the gas giants in the same “very, unimaginably big” bucket. I knew Jupiter was the biggest, then Saturn, but I didn’t realize just HOW big they were compared to the rest. At the risk of stating the very, very obvious, Jupiter is huge!!! Masses of gas g…

The Sun is 99.86% of the mass in our solar system. Jupiter is 0.1% and everything else fits in that last 0.04%

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

#116

Post by andrekandre »

devoutsalsa wrote: post #68
margalabargala wrote: post #65

Earlier quoted context omitted.

Black holes are no more "dangerous" than other objects of equal mass. If a black hole with a mass of, say, Ceres hit the Earth, it would not be particularly worse than if Ceres hit the Earth.

I’d love see a mini-Ceres about this streaming on Nebula.

cerial storytelling ftw ^^

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

#117

Post by airstrike »

ck2 wrote: post #25
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.

There's an episode on "Space & Beyond" where they show all the planets in scale to the realworld on an actual football field. Then to show Planet 9 distance they have to get in a car and drive a few miles. That worked for me.

What is "Space & Beyond"?

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

#119

Post by snapetom »

ednite wrote: post #82
ednite wrote: post #20

Earlier quoted context omitted.

Honestly, if there is a golf ball–sized black hole out there chilling in the outer solar system, I'm all in. Let’s fire up a replica of TARS, load up ChatGPT inside (TARS-GPT, patent pending), and yeet it straight toward the Schwarzschild golf ball. It’ll narrate live. Imagine the livestream: “Approaching event horizon. Spaghettification at 3%. Mood: stretchy.” “Entering gravitational lensing zone… wow, even my token…

Not sure why the downvotes—if I came off wrong, my apologies. I genuinely meant it in a humoristic way. I'd honestly love to see a probe launched into a black hole.

We don't do humor here, and I'm not kidding.

Humor devolves the site into useless one liners. If you want evidence of that, go to reddit and see how useful that site is these days if you want to actually research and learn something. Slashdot knew this back in the day and while funny posts got visibility, they did not add anything to a user's total karma score.

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