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A 1980s space telescope may have seen planet nine

gizmodo.com

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Re: A 1980s space telescope may have seen planet nine

#111

Post by tectonic »

Hallucinaut wrote: post #96
tectonic wrote: post #3

Mike Brown recently wrote a summary of his and Konstantin Batygin's paper 'The orbit of Planet Nine'. By looking at Kuiper belt objects (KBOs) whose orbits appear skewed by the invisible gravity of a possible Planet Nine, accounting for observation bias, and running a ton of simulations and MCMC, they concluded: if it exists, Planet Nine has a mass of 6.2 (+2.2/-1.3) Earth masses and a perihelion (closest approach to…

Love the newsletter by the way. It's the only one out of dozens I receive that I actually read every time. I can recommend anyone that has an interest in anything space related to give it a read.

Thank you! I’m glad you’re enjoying it.

Re: A 1980s space telescope may have seen planet nine

#113

Post by dalkvist »

tiahura wrote: post #89

Can anyone explain how we’re able to detect dozens of exoplanets (Wiki says we’re up to 4864!), but not be able to detect every large boulder around our own star?

The way we detect things in our own solar system is basically to take several images of the same patch of sky and look for things that moved. Objects that far out have a slow apparent motion and require repited observations days apart. We have a limited amount of telescopes that are sensitive enough and time on them are very competitive. But we have new telescopes on the way and on the next few years there will likely be many more confirmed objects on the outer solar system.

Re: A 1980s space telescope may have seen planet nine

#115

Post by go_elmo »

ziddoap wrote: post #11
gre wrote: post #7

Here's a youtube video by Anton Petrov describing the paper https://www.youtube.com/watch?v=ZSyAO4fGZOE

He's always quick on these, and always with quality videos. Anyone with an interest in space who has not watched any of Anton's videos are seriously missing out.

Thats me! thanks for the input. Yt really puts you in a bubble unfortunately. Would be cool if one could "explore" different branches of it...

Re: A 1980s space telescope may have seen planet nine

#116

Post by EdwardDiego »

irjustin wrote: post #106
zionic wrote: post #64

Earlier quoted context omitted.

I’m just mad we’re losing out on “Planet X”. When I was a kid Pluto was a planet so the new one was X (10) and it was cool. Now this new planet is just going to be planet 9 again… totally lame.

Oh man this was me! I 100% agreed until I saw relative size of Pluto[0]. Definitely seems unfair to call it a planet when there's a number of Kuiper belt objects that are larger[1](?) or pretty much the same size. [0] https://www.quora.com/Why-is-Pluto-so-different-from-the-oth... [1] https://www.universetoday.com/118118/it-looks-like-these-are...

Can't we just add Pluto and Charon together and say "by your ~powers~ masses combined, I am ~Captain~ the ninth Planet!"

Re: A 1980s space telescope may have seen planet nine

#117

Post by widforss »

netcraft wrote: post #91
tiahura wrote: post #89

Can anyone explain how we’re able to detect dozens of exoplanets (Wiki says we’re up to 4864!), but not be able to detect every large boulder around our own star?

There are two main ways we detect exoplanets. The primary way that I believe accounts for the vast majority of planets we have detected is the transit method. Basically we watch the light from a star very closely and look for a dip in the amount of light coming from it as a planet transits in between us and the star. This of course depends on the planet to pass directly between us and the star, and that means that it…

If that is the threshold for discovering exoplanets, haven't we already found Planet Nine since we definetly have detected the planet's effects?

Re: A 1980s space telescope may have seen planet nine

#118

Post by WithinReason »

post-it wrote: post #65
zionic wrote: post #64

Earlier quoted context omitted.

I’m just mad we’re losing out on “Planet X”. When I was a kid Pluto was a planet so the new one was X (10) and it was cool. Now this new planet is just going to be planet 9 again… totally lame.

Maybe there's a second one!

Planet 9 II

Re: A 1980s space telescope may have seen planet nine

#119

Post by Robotbeat »

irjustin wrote: post #106
zionic wrote: post #64

Earlier quoted context omitted.

I’m just mad we’re losing out on “Planet X”. When I was a kid Pluto was a planet so the new one was X (10) and it was cool. Now this new planet is just going to be planet 9 again… totally lame.

Oh man this was me! I 100% agreed until I saw relative size of Pluto[0]. Definitely seems unfair to call it a planet when there's a number of Kuiper belt objects that are larger[1](?) or pretty much the same size. [0] https://www.quora.com/Why-is-Pluto-so-different-from-the-oth... [1] https://www.universetoday.com/118118/it-looks-like-these-are...

Planetary scientists tend to consider Pluto, and those large Kuiper Belt Objects, to be “planets.” It’s just certain astronomers, who don’t usually study planets, who voted to remove them from planethood. https://www.ucf.edu/news/pluto-planet-research/?amp

Pluto is an impressive planetary system with a bunch of Moons and active geology. I’m gonna call it a planet.

Also kind of funny, but this guy who is obsessed with finding “Planet 9” (which doesn’t seem to exist) is also the one who tried and succeeded at demoting Pluto.

Re: A 1980s space telescope may have seen planet nine

#120

Post by hnbad »

SkittyDog wrote: post #59
odyssey7 wrote: post #48

Earlier quoted context omitted.

The sufficient-but-not-necessary conditions for identifying a planet are called into question as a workable definition once more. We’ve duck-typed the solar system, I guess.

I hate to be the one to break the bad news to you, but... That's pretty much how all science works. https://en.m.wikipedia.org/wiki/Species_concept Categorization is a leaky abstraction. Use them when they're useful, and ignore them when they become more trouble than they're worth.

This is an example I also find helpful when dealing with people who insist that "there are only two genders" ("because science"). Even species is a leaky abstraction, let alone sex, gender and sexual attraction. You can argue for a strict gender binary normatively (and we can disagree on that), but even if you try to conflate gender and sex it's still scientifically illiterate to insist that there is a strict binary (although for sex at least humans are bimodal).

Leaky abstractions can still be useful but you have to be aware that they're just abstractions and still understand that reality is messy and complicated or you'll end up legislating the value pi.

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