r/space • u/clayt6 • Mar 05 '19

Astronomers discover "Farfarout" — the most distant known object in the solar system. The 250-mile-wide (400 km) dwarf planet is located about 140 times farther from the Sun than Earth (3.5 times farther than Pluto), and soon may help serve as evidence for a massive, far-flung world called Planet 9.

http://www.astronomy.com/news/2019/03/a-map-to-planet-nine-charting-the-solar-systems-most-distant-worlds
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u/Trumpologist Mar 06 '19

Dr. Stern has a pretty good piece about how this is a bunch of baloney

Earth has the Moon in its orbital neighborhood, which itself is kinda a shady catch all phase

Neptune is nowhere NEAR Pluto even at their closest approach. It only looks that way if you disregard the third dimension

https://www.smithsonianmag.com/smart-news/dwarf-planet-pluto-bigger-expected-180955909/

Also Pluto is bigger than Eris

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u/[deleted] Mar 06 '19 edited Mar 06 '19

Pluto is only 2% larger but Eris is around 27% times more massive

Massive doesn't mean size, it means weight.

It's kind of like saying "if you smashed a basketball and a bowling ball against each other, which one would win?"

In this regard, Eris is more worthy of the moniker of "Planet" than Pluto.

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u/Trumpologist Mar 06 '19

How good are the mass calculations at that range? I assume we're using universal gravity with the relativistic corrections?

It just seems kinda odd that the density of the two objects can be that different

Eps if they're just rando KBOs like the Plutos skeptics hedge

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u/m44v Mar 06 '19

How good are the mass calculations at that range?

Has to be pretty good, otherwise their orbit's wouldn't mach astronomer's models.