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r4pt0r

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In reference to todays' close up mosaic of Tombaugh Reggios' carbon monoxide ... uhhh... ice field(??) I guess. I don't see any impact craters there either.

If that remains to be true, it is pretty big news. Even with our soupy atmosphere and pretty drastic erosion, impact craters are visible from space on Earth.

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If that remains to be true, it is pretty big news. Even with our soupy atmosphere and pretty drastic erosion, impact craters are visible from space on Earth.

Two things might keep the numbers down, probably less junk in an area then in the inner solar system, relative speeds should also be lower.

Still its puzzling, how long would Pluto be active because of tidal effects from Charon? It would still give off energy until both start wobbling and the orbit is circular.

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Two things might keep the numbers down, probably less junk in an area then in the inner solar system, relative speeds should also be lower.

Still its puzzling, how long would Pluto be active because of tidal effects from Charon? It would still give off energy until both start wobbling and the orbit is circular.

According to NH team, the tidal effects would have lasted only a few million years (citation needed, but one of the team basically said that at one of the media conferences IIRC).

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Am I the only one thinking "Great place for a miner, right on the equator!" when I see this?

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Are we looking at the same thing? The dark parts look like shadows, but the possible wind streaks are the lighter smudges. Looks quite likely to me.

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Two things might keep the numbers down, probably less junk in an area then in the inner solar system,

I'm not so sure the Kuiper belt is less crowded than the inner solar system.

relative speeds should also be lower.

Yes, low velocity impacts are probably common for Pluto.

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I'm not so sure the Kuiper belt is less crowded than the inner solar system.

It's not less crowded because impacts don't happen that often, so whilst the inner solar system population drastically declines impact after impact, the outer solar system still has a lot more objects. Impacts out there don't happen as much for a lot of reasons: there's more space, so less chances of colliding with something; most objects nowdays are in eccentric and inclined orbits, making impacts even less likely; etc. Plus, out there all objects move much more slowly than in the inner solar system, so it's unlikely impact speeds exceed 1-2 km/s.

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I'm not so sure the Kuiper belt is less crowded than the inner solar system.

Yes, low velocity impacts are probably common for Pluto.

Lowering

-Fractional gravity relative to Earth and Moon.

-Charon is relatively bigger than the moon relative to earth and lots of other satellites (offering a scavaging function)

-Neptune performs a clearing function for Most of plutos orbital path.

-Orbital speed is much lower than the Earth, therefore inclination crossing objects will be slowe.r

Raising.

-No clearing functions outside of plutos orbit, therefore no protection from objects that come in from Oort cloud (Jupiter, Saturn and Mars protect earth from by being alternative targets).

-Orbit is already highly inclined, counter inclined objects will impact with higher speed

-Pluto's orbit maybe, ultimately, unstable, and interaction with passing objects may raise potential of a collision with Neptune or ejection the transNeptunian orbit.

One also has to factor in total energy which is 0.5 * mass * velocity^2. Since there is no clearing function outside of pluto, perturbations by passing stars and brown dwarfs or dead stars are more likely to alter the course of oort cloud objects that reach plutos orbit, hydra itself looks like a large captured asteroid (though the mechanism of how it was captured is bewildering). But the objects drafted into pluto's orbit could be quite large. However at Pluto's orbital speed once a inevitable impactor is place in its orbit, it may take several billion years for the impact to occur because its radial velocity is so slow.

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According to NH team, the tidal effects would have lasted only a few million years (citation needed, but one of the team basically said that at one of the media conferences IIRC).

That was short then the moon still gives plenty of effect after billions of years.

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That was short then the moon still gives plenty of effect after billions of years.

Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy.

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That was short then the moon still gives plenty of effect after billions of years.

Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy. Io's tidal bulge reduces it to a smoldering sulfur pit because it librates back and forth due to its non-circular orbit (non-circular because the other moons have pumped-up its orbital eccentricity, like I already said). Pluto's other moons are many many many orders of magnitude too small to have any gravitational effect on Charon.

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Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy. Io's tidal bulge reduces it to a smoldering sulfur pit because it librates back and forth due to its non-circular orbit (non-circular because the other moons have pumped-up its orbital eccentricity, like I already said). Pluto's other moons are many many many orders of magnitude too small to have any gravitational effect on Charon.

While it is perfectly true that no tidal heating is being generated, it's also true that such locked relationships can sometimes widen the amount of activity. Say a relatively big body strikes one of them; the resulting torque will be transferred to the other one too. Now, we haven't seen major impact crater yet, however bear in mind that 1) resurficing on Pluto is still ongoing as ices sublimate and deposit 2) while it is true that in the outer solar system impacts almost never exceed 1-2 km/s, Pluto and Charon are also small bodies, so you don't necessarily need a huge impactor to generate some heat. Plus, I've heard others say that even just the seasonal sublimation/freezing cycle could lead to asymmetrical mass re-distributions which in turn could lead to some imbalance in the locked system and generate heat. And even if that wasn't the case, any imbalance of any other nature could be amplified by a positive feedback resonance. You know, Pluto is perturbed, the perturbation is transferred to Charon, then back to Pluto etc. I suspect that after a while things would settle down, but I guess it's at least plausible that this tidal lock relationship could be amplifying some activity.

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Well, landing site selected then... who are we gunna send, Jeb? Val or both....

oh wait... yes, game play gets in the way of reality again...

but seriously, that would be a good landing spot. :)

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Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy.

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Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy. Io's tidal bulge reduces it to a smoldering sulfur pit because it librates back and forth due to its non-circular orbit (non-circular because the other moons have pumped-up its orbital eccentricity, like I already said). Pluto's other moons are many many many orders of magnitude too small to have any gravitational effect on Charon.

What you said about the orbits is true... NOW.... but in the past?

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What you said about the orbits is true... NOW.... but in the past?

(Responding to this although it wasn't directed to me) yes, things weren't straightforward. A tidal lock requires time, with the bodies slowly adjusting their orbital properties to match each other's.

Lowering

.....

-Neptune performs a clearing function for Most of plutos orbital path.

"Clearing" isn't really the word I would use there. First of all, all of the Kuiper belt population, except the cubewanos, is defined because of its orbital resonances (plutinos, twotinos...) with Neptune. So Neptune isn't really clearing anything, it's just throwing things around. Sure, in the past it probably cleared up a lot of stuff, but a lot of it survived too and still exists today. That's even more evident if you considered the scattered disk too. Sure, it's not part of the Kuiper belt, but most of the SDOs dive deep into it for most of their orbital paths.

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Well, landing site selected then... who are we gunna send, Jeb? Val or both....

oh wait... yes, game play gets in the way of reality again...

but seriously, that would be a good landing spot. :)

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What you said about the orbits is true... NOW.... but in the past?

It wouldn't have taken very long at all for them to stabilize into their current configuration, probably only a few million years. They are very close to each other and very close in mass. The solar system is 4.6 billion years old. Pluto and Charon should have long ago cooled and died. Charon appears to have done that- or at least, far more than Pluto- as Charon is covered with a lot of craters. Whatever the heck is going on on Pluto can't have anything to do with tidal heating. There is none and there hasn't been any for many billions of years.

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What you said about the orbits is true... NOW.... but in the past?

Sure, in the past they had tidal forces acting on them actively. But the evidence of that (at least as far as this flyby goes) is long hidden by what's happened to them since they got into their perfect dance.

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A relevant and recent paper describing tectonic activity on Pluto after the Charon-forming impact:

In successful hydrodynamical simulations of the Charon-forming impact, Charon is launched into an eccentric orbit around a rapidly spinning Pluto< its initial orbital semi-major axis after the impact, ao, ranges from ∼3.7RP to 21RP. Over a time scale Äsynch∼35(Qc/100) years, where Qc∼100 is a nominal estimate of Charon’s tidal quality factor, Charon evolves to a synchronous state in which its spin period and orbital period are equal (similar to the Earth–Moon system). The final migration from the synchronous state to the dual-synchronous state takes much longer, 1-s2.0-S0019103514001687-si39.gif, where Qp is Pluto’s tidal quality factor, and k2,p is the degree-2 Love number that describes how Pluto’s gravitational potential changes in response to the tides raised on Pluto by Charon.

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Pluto and Charon are in circular orbits around each other and their rotation speeds are perfectly synchronous. There are no other moons to pump up the eccentricity of Charon's orbit (like there are in the Jovian and Saturnian systems). Therefore, Charon generates no tidal energy in Pluto (and vice versa) because the tidal bulges NEVER MOVE. A static, non-moving tidal bulge generates zero energy.

I know, I was just suprised that they ended up perfectly tidal locked so fast. Probably as they are close and that the masses are small compared to earth and moon

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I did some processing.

newhorizons_sputnikplanum_monocolor_lw.png

I've averaged the color and lightness of the region and used the average value to colorize the LORRI image. Also, some minor removal of those giant pixelated areas.

Edited by lajoswinkler
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