Dwarf planets are apparently somewhat plentiful in our solar system, but such a giant would really tickle the fantasy even if far from the sun.
It is just the farthest out right now.
There are likely many, many more we haven't found yet.
For comparison it is often announced in the media that voyagers 1 and 2 have "left the solar system". Voyager 1 is about 144AU out right now. There are things in orbit of the sun with aphelions from 1500 to 3000AU.
I don't even know you people any more!
If you look at the second diagram some of the orbits are very elliptical so the distance from the sun changes significantly. And it's also not the case that one objects it always the same "rank" from the sun.
"2018 VG18 is much more distant and slower moving than any other observed Solar System object, so it will take a few years to fully determine its orbit."
(a) orbits the sun, (b) has sufficient mass to be round, or nearly round, (c) is not a satellite (moon) of another object, and (d) has removed debris and small objects from the area around its orbit
The dwarf "planets" often suffer from not being round (enough), and even more from not clearing out their debris in their orbit.
I don't know what to do with the information that its diameter is 500km. I guess that makes it 1/5 of Pluto's diameter, and given that Pluto is called a dwarf planet...
"(b) has sufficient mass for its self-gravity to overcome rigid body forces so that it assumes a hydrostatic equilibrium (nearly round) shape, "
If Farout is highly icy 500km could be enough to qualify it.
Regardless it isn't nearly massive enough to clear it's orbit.
I believe the mass and orbital parameters necessary to clear an orbit of debris are known pretty well known theoretically, and farout won't satisfy it. This is why astronomers can "be looking for Planet 9/X/10" without searching for debris everywhere. (Likewise, knowing the rough mass is enough to know whether a body has a hydrostatic shape; you don't have to actually resolve it's shape in your telescope.)
Edit: yep: https://en.wikipedia.org/wiki/Clearing_the_neighbourhood#Cri...
Notably, Ceres is about 950km and much more spherical.
An asteroid could be perfectly round, but its shape is based on material strength and not just gravity.
The 'cleared it's orbit' thing is also arbitrary. Pluto is sometimes closer to the Sun than Neptune for example but does that mean they share an orbit? It's mainly to exclude Ceres, which is pretty close to spherical.
The problem is any rules that exclude Ceres and also exclude the other trans-Plutonian planetoids also end up excluding Pluto. If Pluto is a planet and this new thing, why not Eris, Haumea, Sedna, orcus, etc, etc, etc.There are many dozens of them.
We do have applicable terms - planetoid, dwarf planet, so why not use them?
Not really, the degree to which a body has cleared its orbit can be calculated: https://en.wikipedia.org/wiki/Clearing_the_neighbourhood
> Pluto is sometimes closer to the Sun than Neptune for example but does that mean they share an orbit?
Pluto is locked in a resonant orbit with Neptune, a position it reached due to the influence of Neptune's gravity:
What I don't like about the "cleared its orbit" criterion is that it's something you can't tell from looking at the object itself. If a planet is ejected from its orbit, it becomes a ... well, we don't even have a name for what it would be. (This problem exists for "moon" to a certain extent, but a moon that's thrown out of planetary orbit would become a planet if it was big enough and an asteroid if it wasn't). It's also hard to apply: a lot of extrasolar planets we're discovering will have to be reclassified once we get better at finding smaller bodies, just like in this solar system.
Dwarf planet is a helpful term in some contexts but not others. The solar system is a dynamic system, when talking about the whole thing or its evolution it's useful to distinguish between planets and dwarfs.
Q is not impressed.
'Correct. The Bank is now in orbit forty million miles out beyond - what's the name of your outermost world?'
'Far Out,' said Tarli.
-- 'The Dark Side of the Sun', Terry Pratchett