Pluto atmosphere is 'upside down'.

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VLT discovers Pluto's atmosphere is warmer than expected.

Quite a find.

What I wonder about this find, is if variations globally could be mapped, i.e if Pluto has active cryovolcanism. Also could these observations be used to see if there is a transfer of gas between Pluto & Charon?

Could the same VLT observations be carried out on the largest currently known KBO Eris?

New Horizons will answer the cryovolcanism question for sure as a large part of Pluto’s surface will be imaged at high resolution (Charon’s too).

Andrew Brown.
 
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MeteorWayne

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Very cool (well actually, bloody cold) stuff!
Thanx Andrew.
 
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It is incredibly fascinating stuff Wayne.

As you can see, I have already thought of some developments that could come from this.

This will also help in planning in greater detail, the upcoming New Horizons pass, to assist in honing the use of the on board instruments to greater effect.

I certainly think that these observations if continued could map potential 'hot spots' above potential cryovolcanoes (if they exist on Pluto) as you say still blooming chilly by terrestrial standards.

An inversion of upto -170 C, that's approx 10 C warmer than Titan's atmosphere at the surface. Very warm considering Pluto's location within the Kuiper Belt.

Wonder if similar observations could be carried out on Eris?

Andrew Brown.
 
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MeteorWayne

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Well, perhaps. It is 3 times further away, and you need a stellar occultation for the method to work. I wonder what the magnitude of the star was that was used for the measurements. Eris (at that distance) is a much smaller target, so the occultation circumstance would have to be almost perfect.
Still an interesting idea!

It would have been nice if the article had mentioned what journal it was being published in.... :x
 
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neilsox

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Apparently measuring the temperature of an almost vacuum can lead to large errors. Earth's atmospheric temperature in LEO = low Earth orbit has been measured at hundreds of degrees f. Temperature inversions are common for planets. Neil
 
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h2ouniverse

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In addition to the apparent diamter argument, Pluto is currently in front of the milky way. And Eris is not. So far more occultation opportunities for Pluto. You see Wayne why space-based occultation chasers would add value...
Quaoar is in front of the Milky Way.
And as Pluto is in MWay, so is Charon...

This being said, are you sure that their method involves stellar occultation? In that case they would need the ground track to pass right over VLT, which I doubt. I haven't seen explicit mention of a stellar occultation for their work.
 
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stupidlaminatedrock

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Arent Pluto and Charon more or less Binary? Meaning there may be some tidal heating involved?
 
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h2ouniverse

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stupidlaminatedrock":2p82ew1i said:
Arent Pluto and Charon more or less Binary? Meaning there may be some tidal heating involved?

They are a binary but they are tidally locked vs each other=> no more tidal heating (long ago). To have tidal heating you need to transfer either spin energy (Earth's spin decreases because of tidal dissipation from our Moon, as the Moon has not yet locked Earth) and/or orbital energy (Io Europa and Ganymede exchange orbital energy because of their mean motion resonance, which perturbates their tidal locking vs Jupiter and transfers tidal energy to all three moons).
The only hope for some tidal heating remaining would be the influence of Nix and Hydra but their masses are probably too small to disturb signficantly the Pluto-Charon pair. They computed IIRC an induced precession of Charon of just 0.0002°. There was a hope that they would have a 6:4:1 resonance with Charon but a recent study could not find resonant arguments. http://arxiv.org/abs/0712.1261

Methane atmosphere can be explained by the thermal cycling due to Pluto's excentricity.
Cryovolcanism might be possible merely as a consequence of radiogeny and thermal inertia of bodies larger than about 1000km (for a density of 2) => see this thread viewtopic.php?f=12&t=4603

Best regards
 
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3488

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Hi joel,

Yes I too am doubtful of current cryovolcanic activity on either Pluto or Charon, though Charon does appear to display crystalline ice.

However, we cannot assume, but IMO, Pluto will be fairly primitive, heavily cratered, but methane ice will be present as a veneer.

AFAIK, Pluto has not been wrenched around in the past like Triton (following capture by Neptune) or currently like Io & Enceladus with Jupiter & Saturn respectively.

However, we do not really know & I think we will not until New Horizons carries out the encounter, though more observations like this may assist in generating a more global picture of the atmospheric temperatures, pressure & composition.

Andrew Brown.
 
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