Pluto Predictions, What will NH find? Options

[Juramike]

Dunes.

And basins.

Maybe not as thoroughly chemically processed as Titan's basins, but basins.



What do you think New Horizons will find at Pluto? How will Pluto surprise us?

-Mike

[Juramike]

After such an impact, there must've been an aweful lot of tidal friction generated on both bodies as the system locked up into its current configuration. How much heat would have been generated, and how would this have affected the crust and surface of Pluto?

Even now, how much tidal libration is in the system? (How eccentric is Pluto-Charons orbital couple?) And would this tidal energy get evenly distributed or would there be sub-crustal hotspots at certain points?

-Mike

[Rob Pinnegar]

After such an impact, there must've been an aweful lot of tidal friction generated on both bodies as the system locked up into its current configuration. How much heat would have been generated, and how would this have affected the crust and surface of Pluto?

Even now, how much tidal libration is in the system? (How eccentric is Pluto-Charons orbital couple?) And would this tidal energy get evenly distributed or would there be sub-crustal hotspots at certain points?

-Mike

Well, ultimately the energy would have had to come from the orbital energy of Pluto and Charon around each other. That would put limits on the available energy. This wouldn't be an Io-like case where the energy source is Jupiter's rotation, which for all intents and purposes is inexhaustible.

Maybe a little energy could come from librational motion, but it's hard to imagine it could amount to much.

One other thing to keep in mind is that Pluto and Charon are mutually tidally locked. That means that Charon shouldn't be moving away from Pluto any more, the way the Moon is gradually moving away from the Earth. Their orbits around each other are fixed, except for solar perturbations, and what little comes from Nix and Hydra and other KBOs, and the giant planets.

Actually, I guess that some information about the past evolution of this system might be obtained by observing that Nix and Hydra don't appear to have been captured into resonances with Charon (at least this was the case last time I read up on it). That implies that there couldn't have been *too* much tidal energy dissipated. If there had been, Charon's semimajor axis would have increased enough for Nix and Hydra to get "grabbed" into resonances at some point.

(Mind you, Charon's so big relative to Pluto that it would take a *lot* of slowing-down of Pluto's rotational period to move it out very far... hmmm, this gets more complicated. Guess I might have to stop speculating, and actually do the math.)