Pluto & Neptune

[rick95838]

Will Neptune ever get close enough to pluto to send it in or out of our solar system?

[Grashtel]

Will Neptune ever get close enough to pluto to send it in or out of our solar system?

No, they are in an orbital resonance so will never approach close enough despite their orbits crossing.

[mugaliens]

Uh, sorry, but Pluto's orbit crosses that of Neptune in an oblique and very stabilizing manner.

[Celestial Mechanic]

Uh, sorry, but Pluto's orbit crosses that of Neptune in an oblique and very stabilizing manner.

However, the tilt of Pluto's orbit places the perihelion far below the plane of Neptune's orbit. Neptune and Pluto will never be any closer than 17 AU.

[Jeff Root]

Smaller bodies have been discovered that have the same 2:3 resonance
with Neptune's orbital period as Pluto has. Enough of them that they've
been given a family name of "Plutinos".

-- Jeff, in Minneapolis

[Celestial Mechanic]

There are also some Plutinos at the 4:3 resonance as well. The same principles apply. They will never approach Neptune close enough for them to experience massive perturbations.

[tony873004]

I'm not aware of the 4:3's, but there are pleanty of 2:1's. They're not called Plutinos, however. They're Twotinos.

[grant hutchison]

I'm not aware of the 4:3's, but there are pleanty of 2:1's.

Are they perhaps the same thing? 2:1 with Neptune = 4:3 with Pluto.

Grant Hutchison

[tony873004]

Are they perhaps the same thing? 2:1 with Neptune = 4:3 with Pluto.

Grant Hutchison

Perhaps. That may very well be what Celestial Mechanic was referring to, as the math works:
The KBO take 2 Neptune years to orbit the Sun, vs. 1.5 Neptune years for Pluto. 2:1.5 = 4:3.
But it would be strange to describe its resonance wrt Pluto, because it's only in resonance with Pluto as a result of it and Pluto being in resonance with Neptune. i.e. If Pluto suddenly disappeared , the 2:1 Neptune:KBO resonance would remain intact, but if Neptune suddenly disappeared, the 4:3 Pluto:KBO mean-motion resonance would disappear too.

[Celestial Mechanic]

I'm not aware of the 4:3's, but there are pleanty of 2:1's. They're not called Plutinos, however. They're Twotinos.

Sorry, my memory has failed me once again. A quick Google led me to David Jewitt's Kuiper Belt page onThe Plutinos and there is only one (1995 DA2) suspected of being a 4:3 resonance with Neptune.