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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

#71

Post by WarOnPrivacy »

SllX wrote: post #52
tick_tock_tick wrote: post #47

Earlier quoted context omitted.

> "progress." Do you really think Starlink is not a step forward? It is realistically the only path to get the whole world access to the internet.

If by “whole world” you mean the wilderness, then sure! Otherwise we’ve had no issues laying cables to any place people live, so long as it makes sense to do so.

If by "makes sense" you mean to ISP shareholders - for ISPs to take federal USF funds and never, ever deliver on the required upgrades or expansions (eg:Frontier@WV,Verizon@PA), due to regulatory capture.

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

#72

Post by twobitshifter »

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.

My favorite example of this is that trees aren’t really a phylogenetic group all their own. They’re just plants and plants can become tall and woody with a few genetic tweaks. You can’t trace trees to a common ancestor because the ancestors of many types of trees are just ordinary plants.

https://eukaryotewritesblog.com/2021/05/02/theres-no-such-th...

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

#73

Post by kibwen »

nsf39k wrote: post #42
HenryKissinger wrote: post #8

If Planet 9 contains rare earth metals, mining and manufacturing facilities could be built there. This should help alleviate the chip shortage.

The technology and infrastructure needed to reach Planet 9, build a mining outpost, then transport everything back at a profitable cost is likely decades if not centuries away. That’s not counting the fact that Planet 9 is so far away that getting there with current technology is a lengthy affair in itself (the New Horizons probe wouldn’t even be halfway to a theoretical Planet 9, and it’s been flying for over 15 yea…

> likely decades if not centuries away

The fastest man-made object ever launched was the New Horizons spacecraft. Headed on an intercept course for Pluto 30 AUs away, it took 9.5 years to get there. And that's without slowing down; if you actually wanted to land on Pluto you would need to spend even more time actually slowing down. The object in the OP is 225 AU away (which is dramatically closer than prior estimates of the distance of Planet 9 (300 AU)). All this means that, even moving as fast as we have ever launched a spacecraft, it would take at least 70 years for a probe to reach Planet 9, even without taking time to slow down. A probe launched today would return with its cargo no sooner than 2160. That's probably never going to be economical, even with future improvements to spacecraft propulsion (moving faster just means you need more and more fuel to slow down, at which point you are beholden to the tyranny of the rocket fuel equation).

It's easy to forget the scales here. We're used to Pluto being our reference point for "far edge of the solar system", and it's easy to conclude that Planet 9 is about as far as Pluto, but it's so much farther. Voyager 1 is a bit more than halfway that far.

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

#74

Post by labster »

pchristensen wrote: post #60
ufo wrote: post #56

Earlier quoted context omitted.

According to Mike Brown, the infrared sighting from Rowan-Robinson is in a different location in the sky than was predicted by the aforementioned Planet Nine hypothesis. In other words, if this infrared sighting is real it would be a different Planet Nine! https://twitter.com/plutokiller/status/1458038427090178052

Planet 9 3/4?

Isn’t that where you board Galaxy Express 999?

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

#76

Post by ademup »

twobitshifter wrote: post #72
SkittyDog wrote: post #59

Earlier quoted context omitted.

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.

My favorite example of this is that trees aren’t really a phylogenetic group all their own. They’re just plants and plants can become tall and woody with a few genetic tweaks. You can’t trace trees to a common ancestor because the ancestors of many types of trees are just ordinary plants. https://eukaryotewritesblog.com/2021/05/02/theres-no-such-th...

Same goes for fish, which I just read in the excellent book "Why Fish Don't Exist" by Lulu Miller. An example being that a lungfish has more attributes similar to a cow than to a salmon.

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

#77

Post by svachalek »

staticautomatic wrote: post #50
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…

Perhaps a dumb question, but if we have some idea of where it was and its probable orbit back then, then why don’t we have some idea of where it is now?

"Some idea" is the problem. Basically at the orbit we think it's at, even at the relatively large size they're expecting, it would be a tiny, tiny black dot. It's the proverbial needle in a haystack, knowing which haystack it's in is only the beginning.

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

#78

Post by rossdavidh »

HenryKissinger wrote: post #8

If Planet 9 contains rare earth metals, mining and manufacturing facilities could be built there. This should help alleviate the chip shortage.

You're joke (it's a joke, right?) is apparently humor that's a little too dry to be detected as such.

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

#79

Post by __MatrixMan__ »

kordlessagain wrote: post #75

If whomever was responsible for demoting Pluto from being planet nine is reading this, you’re a dweeb.

I'm not that guy, but I took a semester of astrophysics so I'm practically an expert.

If you drop the "has cleared its orbit of most obstacles" criterion, you have to admit something like 105 new planets. Pluto will always have a special place in our hearts, but it had to be done.

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

#80

Post by jhgb »

pfdietz wrote: post #28
HenryKissinger wrote: post #8

If Planet 9 contains rare earth metals, mining and manufacturing facilities could be built there. This should help alleviate the chip shortage.

Rare earths are neither particularly rare, nor particularly likely to be unusually abundant on a Planet 9. However! A Mars or Earth-sized planet sufficiently far out in the solar system might be sufficiently cool to be able to retain helium in its atmosphere, without being a gas giant planet. If so, it might conceivably be the best place in the solar system to obtain 3He, an isotope that has considerable attractivene…

I don't see how the "attractiveness" of helium-3 is anything non-zero. If you can't even fuse deuterium with tritium, which is the easiest thing there is, helium-3 fusion goes out of the window.
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