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A 1980s space telescope may have seen planet nine

gizmodo.com

51–60 of 137 posts

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

#52

Earlier quoted context omitted.

Not true at all, totally depends on the type of observation campaign. Plenty of big observatory projects are negatively impacted by the eternal march of "progress."

> "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.

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

#53
post #28

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…

The moon already has a whole lot of helium 3 that'd be economically viable right now, if there were a use for it yet.

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

#54

Earlier quoted context omitted.

There’s all kinds of silly names they could borrow from stories hypothesizing its existence. Nemesis, Nibiru, Vulcan, and Planet X, just for starters. But in all likelihood it will end up as something much more anodyne.

I think the IAU will only accept names from Mythology.

There's a region on Pluto provisionally named after Cthulhu, citing Lovecraft as "an underworld mythology". If the IAU accepts the name, it would make this possible too.

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

#55
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?

Yes we should.

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

#56
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…

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

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

#57
post #28

Earlier quoted context omitted.

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…

The moon already has a whole lot of helium 3 that'd be economically viable right now, if there were a use for it yet.

The moon has 3He, at a concentration of maybe 10ppb, in regolith the heating of which would use more energy than the released 3He would yield in fusion.

Helium at cosmic isotope ratios is 120ppm 3He. So if there were a planet out there with an atmosphere of this helium, extracting the 3He would be much easier (just compress, liquefy and separate, which you'd have to do with lunar helium anyway.)

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

#58

Earlier quoted context omitted.

An object with multiple Earth masses could hardly be classified as a dwarf planet.

It very well could. Defining a planet as major or dwarf goes by its ability or inability to "clear the neighborhood", to control or remove objects of smaller mass in its orbital area. 225 AU is a long way, and the volume of space to clear goes up quadratically with distance; this object would have 50,000 times more space to clear than does Earth. The orbital period also goes up with distance [edit, reply is right tha…

>ability or inability to "clear the neighborhood",

who said it has finished the job? has the correct paper work be filed? according to the permits in the galactic construction offices, the work is not scheduled for completion for a few hundred more millennia.

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

#59
post #10

If this object did exist, wouldn't it be classified as a dwarf planet since, like Pluto, with a highly elliptical orbit it would be difficult to clear it of other Kuiper belt objects?

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.

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

#60
post #56
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…

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?
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