Rocky Bits in Comets: Formation from Dust?

[anorlunda]

Wikipedia says "Cometary nuclei are composed of an amalgamation of rock, dust, water ice, and frozen gases such as carbon dioxide, carbon monoxide, methane, and ammonia.["

I don't see where the rock comes from. In my mind, rock can be formed from dust only by application to lots of heat and pressure.

How did Kupier Belt objects get exposed to heat and pressure?

Or is there another mechanism to form rock from dust?

Or did the rocky bits form in the inner parts of the disc and get ejected to the outer parts?

 

[davenn]

How did Kupier Belt objects get exposed to heat and pressure?

not all comets come from the Kuiper Belt many of them originate from the asteroid belt
That doesn't negate the possibility of lumps of rock existing further out left over from the formation of the solar system :)

I suggest you are looking at it with a slightly narrowed perspective :)

And from what I have read it would appear as tho this latest comet in the news for the landing there-on, falls into the "within the solar system" origins

Dave

 

[enorbet]

I would venture a guess that collisions would produce heat and pressure.