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Swift
2019-Jan-08, 03:03 PM
Carnegie Science (https://carnegiescience.edu/news/discovered-most-distant-solar-system-object-ever-observed)


A team of astronomers has discovered the most-distant body ever observed in our Solar System. It is the first known Solar System object that has been detected at a distance that is more than 100 times farther than Earth is from the Sun.

The new object was announced on Monday, December 17, 2018, by the International Astronomical Union’s Minor Planet Center and has been given the provisional designation 2018 VG18. The discovery was made by Carnegie’s Scott S. Sheppard, the University of Hawaii’s David Tholen, and Northern Arizona University’s Chad Trujillo.

2018 VG18, nicknamed “Farout” by the discovery team for its extremely distant location, is at about 120 astronomical units (AU), where 1 AU is defined as the distance between the Earth and the Sun. The second-most-distant observed Solar System object is Eris, at about 96 AU. Pluto is currently at about 34 AU, making 2018 VG18 more than three-and-a-half times more distant than the Solar System’s most-famous dwarf planet.

Roger E. Moore
2019-Jan-08, 03:09 PM
I am intrigued, and not just because no one until now has said "far out, man" in the last four decades of my life. :)

Roger E. Moore
2019-Jan-08, 08:01 PM
https://www.astrobio.net/news-exclusive/astrobio-top-10-discovered-the-most-distant-solar-system-object-ever-observed/

Nice summary of the discovery. That's pretty... far out.

George
2019-Jan-08, 08:35 PM
Carnegie Science (https://carnegiescience.edu/news/discovered-most-distant-solar-system-object-ever-observed)

Right arm to Farout! :clap:

Wiki (https://en.wikipedia.org/wiki/2018_VG18) shows it to be at 24.6 magnitude, and they show it at about 500 km in diameter, thus an albedo of about 0.2 is what I calculate to reach that diameter. Some KBOs are at only 0.1 albedo, I think, so it might have a diameter up to 750km, perhaps.

Trebuchet
2019-Jan-09, 02:27 AM
I am intrigued, and not just because no one until now has said "far out, man" in the last four decades of my life. :) Whoa, that blew my mind! Except I'm sure you must have meant five decades....

Is this considered a Kuyper Belt Object? And can New Horizons get there?

Roger E. Moore
2019-Jan-09, 01:35 PM
Is this considered a Kuyper Belt Object? And can New Horizons get there?

I was thinking it was likely a scattered-disk object like Eris, but am not sure. Here is Wikipedia entry. https://en.wikipedia.org/wiki/2018_VG18

Swift
2019-Jan-09, 01:49 PM
And can New Horizons get there?
I would guess the odds are no; I think New Horizons has some limited ability to change course, but unless NASA got real lucky, I suspect it is in the wrong part of the sky. It also would take a heck of a long time to get there, since it is at over 100AU, and NH is currently around around 43AU.

Trebuchet
2019-Jan-09, 06:25 PM
I'm having a little difficulty parsing this from the Wiki article for the orbital period:

929±34 900 years 929 plus or minus 34,900? Negative orbital period?
It's certainly highly eccentric, with aphelion perihlion about at the orbit of Saturn, so sometime in the next 900 years we COULD pay it a visit!

Edited to fix my boo-boo!

Swift
2019-Jan-09, 06:38 PM
I'm having a little difficulty parsing this from the Wiki article for the orbital period:
929 plus or minus 34,900? Negative orbital period?
It's certainly highly eccentric, with aphelion perihlion about at the orbit of Saturn, so sometime in the next 900 years we COULD pay it a visit!

Edited to fix my boo-boo!
At first I thought it was a typo in the wikipedia and they meant 34.900 (just shy of 35 for those who use , and . differently). But no, they mean 34900.

JPL Small Body Database (https://ssd.jpl.nasa.gov/sbdb.cgi?sstr=3836918)

Obviously, you can't have a negative value for orbital period. It means there is so little data that the error bars are still huge, so one should take the orbital period as only slightly better than a guess, IMO. If you look at the uncertainty for the other values, like perihelion and aphelion, they are similarly very large. It might even be premature to say that this object is beyond 100AU; it wouldn't shock me in a year or two if there was a published correction and it was now 98.9AU or whatever.

Roger E. Moore
2019-Feb-22, 04:24 PM
How long until we find FarFarFarFarFarFarOut?

Astronomers discover solar system’s most distant object, nicknamed ‘FarFarOut’
By Paul VoosenFeb. 21, 2019 , 10:15 PM

StupendousMan
2019-Feb-22, 09:29 PM
Well, let's be fair. The link you provided shows that the observations for this object cover a span of just 32 days. Assuming that it is roughly 100 AU away, its orbital period is likely to be of order 1000 years. So the current observations cover roughly

1/12 of 1/1000

of the entire orbit. There are a LOT of orbits of different shapes and sizes which can be made to fit through such a tiny, tiny arc.

publiusr
2019-Feb-22, 11:13 PM
I am intrigued, and not just because no one until now has said "far out, man" in the last four decades of my life. :)

Well, there is Stevo Darkly and Gna: https://www.centauri-dreams.org/2015/12/10/alma-interesting-objects-in-the-outer-system/
"the authors think it most likely that Gna is a bound Centaur in retrograde orbit, currently between 12 and 25 AU out and with a size of 220-880 kilometers."

They can't fool me--with a GNarly name like that, it must have something to do with Stevo pushing shopping carts down a hill sphere and getting all hurt.

Trebuchet
2019-Feb-24, 04:32 PM
Nibiru. Far out, man.