Is it possible Pluto is an ice-ball, a captured comet?

http://www.bbc.com/news/science-environment-35013190

On Friday, December 4, 2015 at 10:51:49 PM UTC-8, RichA wrote:
http://www.bbc.com/news/science-environment-35013190

I'm not sure why the word 'comet' is in the title of this post, but the pictures are spectacular!

On Saturday, December 5, 2015 at 2:02:57 AM UTC-5, palsing wrote:
On Friday, December 4, 2015 at 10:51:49 PM UTC-8, RichA wrote:
http://www.bbc.com/news/science-environment-35013190

I'm not sure why the word 'comet' is in the title of this post, but the pictures are spectacular!

It's composition doesn't seem...planet-like. At least at first glance.

On 12/5/15 12:51 AM, RichA wrote:
http://www.bbc.com/news/science-environment-35013190


Pluto has a density indicative of equal parts rock and ice.

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On Saturday, December 5, 2015 at 9:33:01 AM UTC-5, Sam Wormley wrote:
On 12/5/15 12:51 AM, RichA wrote:
http://www.bbc.com/news/science-environment-35013190


Pluto has a density indicative of equal parts rock and ice.

So do liberals' heads.

On Saturday, December 5, 2015 at 7:33:01 AM UTC-7, Sam Wormley wrote:

Pluto has a density indicative of equal parts rock and ice.

And that is the composition of many comets as well.

John Savard

On Fri, 4 Dec 2015 23:56:32 -0800 (PST), RichA
wrote:

On Saturday, December 5, 2015 at 2:02:57 AM UTC-5, palsing wrote:
On Friday, December 4, 2015 at 10:51:49 PM UTC-8, RichA wrote:
http://www.bbc.com/news/science-environment-35013190

I'm not sure why the word 'comet' is in the title of this post, but the pictures are spectacular!

It's composition doesn't seem...planet-like. At least at first glance.

It's a trans-Neptunian object- a body that probably formed in a part
of the evolved protoplanetary disk that was dominated by ices. So it
is composed of ice and rock, but unlike most trans-Neptunian objects,
is large enough that residual heat and a radioactive core could
generate tectonics and other geological activity for a long time- and
maybe still are.

Not sure what you mean by "planet-like", but it's best to view planets
by class- terrestrial planets being rocky bodies that formed near the
Sun, where most volatiles were lost, then gas giants farther out,
where winds from the protostar didn't blow away all the hydrogen, and
then the icy bodies of the trans-Neptunian objects- KBOs, scattered
disk objects, Oort cloud bodies. Of course, these regions do
contribute comets. That doesn't make Pluto a captured comet, though.
Rather, comets and Pluto may be similar objects in origin, except for
size (rather like asteroids and terrestrial planets are similar).

On Saturday, 5 December 2015 10:34:58 UTC-5, Chris L Peterson wrote:
On Fri, 4 Dec 2015 23:56:32 -0800 (PST), RichA
wrote:

On Saturday, December 5, 2015 at 2:02:57 AM UTC-5, palsing wrote:
On Friday, December 4, 2015 at 10:51:49 PM UTC-8, RichA wrote:
http://www.bbc.com/news/science-environment-35013190

I'm not sure why the word 'comet' is in the title of this post, but the pictures are spectacular!

It's composition doesn't seem...planet-like. At least at first glance.

It's a trans-Neptunian object- a body that probably formed in a part
of the evolved protoplanetary disk that was dominated by ices. So it
is composed of ice and rock, but unlike most trans-Neptunian objects,
is large enough that residual heat and a radioactive core could
generate tectonics and other geological activity for a long time- and
maybe still are.

Not sure what you mean by "planet-like", but it's best to view planets
by class- terrestrial planets being rocky bodies that formed near the
Sun, where most volatiles were lost, then gas giants farther out,
where winds from the protostar didn't blow away all the hydrogen, and
then the icy bodies of the trans-Neptunian objects- KBOs, scattered
disk objects, Oort cloud bodies. Of course, these regions do
contribute comets. That doesn't make Pluto a captured comet, though.
Rather, comets and Pluto may be similar objects in origin, except for
size (rather like asteroids and terrestrial planets are similar).

Even the gas giants have compositions in "shells" such as cores, layers, atmospheres. No idea if Pluto does or is just an agglomeration of ice and rock.

On Mon, 7 Dec 2015 18:26:48 -0800 (PST), RichA
wrote:

Even the gas giants have compositions in "shells" such as cores, layers, atmospheres. No idea if Pluto does or is just an agglomeration of ice and rock.

A body that size would almost certainly have undergone
differentiation, meaning that its structure isn't homogeneous.