Supernova Ejection: How Large Are the Chunks?

[pforeman]

TL;DR Summary

How large does a mass of silica,iron etc have to be for gravity to got this mass to become a rock (asteroid ).

when a star goes supernova, does it eject out earth, mercury and mars sized chunks.
Surely the asteroids that are even the size of Texas won't have enough gravity to compact hard enough to become one chunk.
What is the current belief on how large of chunks are ejected from a supernova.
Thanks

 

[Vanadium 50]

How big is a rock? Where do you draw the line between "dust particle" and "rock"?

BTW, most small objects - like rocks - are held together by chemical bonds, not gravity.

 

[PeterDonis]

Moderator's note: Thread moved to Astronomy forum.

 

[PeterDonis]

chunk

Since the star that went supernova was made of plasma, I'm not sure why you would expect the supernova to eject "chunks" of solid matter. The matter ejected by the supernova is plasma.

 

[snorkack]

It was unexpected, but there are grains in meteorites in which calcium is mainly Ca-44, not Ca-40. Which suggests that these grains originally contained Ti-44, a highly radioactive isotope with half-life 60 years. Thus these grains must have formed in the first century after a supernova explosion in which a lot of radioactive isotopes formed, initially as plasma.

When did the meteorites and asteroids now found fallen on Earth form? Did they form on the cooling and condensation of a supernova plasma, in the first centuries after explosion? Or in hundreds of millennia in interstellar space, after the supernova ejecta dispersed and mixed with preexisting gas clouds? Or only after gas and dust had collected into Solar System?

 

[PeterDonis]

When did the meteorites and asteroids now found fallen on Earth form? Did they form on the cooling and condensation of a supernova plasma, in the first centuries after explosion? Or in hundreds of millennia in interstellar space, after the supernova ejecta dispersed and mixed with preexisting gas clouds? Or only after gas and dust had collected into Solar System?

All of these are possible. I don't know that anyone has a way of ruling out any of them.

 

[EventHorizon]

Since the star that went supernova was made of plasma, I'm not sure why you would expect the supernova to eject "chunks" of solid matter. The matter ejected by the supernova is plasma.

Yes, I agree. Plasma, being ionized gas, does not come out in "chunks", but rather "bursts". If you breathe out on a snowy winter day, your breath would not be seen as coming out in chunks.
As for the core of the supernova, it collapses on itself to form a black hole. None of the heavy elements participate in the ejection.

 

[PeterDonis]

As for the core of the supernova, it collapses on itself to form a black hole.

Or possibly a neutron star if its mass is less than about 3 solar masses.

 

[stefan r]

It depends on circumstances. With most supernova there are no chunks. The material expands and cools. You get solids firming as the cooled material impacts other material.

https://en.wikipedia.org/wiki/Zombie_star

In some 1ax supernovas there is a remnant.

An extreme case would be a nova which is not a supernova at all. There should be an improbable borderline case.

Merger collisions offer some additional variation with fragments of one or the other or both remaining.

Direct impact collision is so unlikely that it is disregarded by astronomers. The word "collision" implies a merger. However, direct impacts are in the realm of "possible". Especially if you include deliberate contrived circumstances set up by Kardashev III civilizations. That is not useful for observation but I think very useful for framing hypothetical "what if" thought experiments.

I claim with enough engineering you could rig it to explode a shower of fragments. Though that set up would require structures that are nothing like stars except having stellar mass.

 

[hutchphd]

by Kardashev III civilizations

say what?

 

[stefan r]

say what?

https://en.wikipedia.org/wiki/Kardashev_scale

Some things are impossible. Traveling faster than light for example. Other things are just out of budget.

If your lab has a budget that includes using over 10^30 kg of material for a simple experiment demonstrating things that you already know then a supernova demonstration is within budget. Set up time is usually at least millennia and more likely millions or billions of years. A K3 lab demonstration is not something you set up for physics class next week.

The difference between "things that will never happen because absurd" and "things that can never happen because of the laws of physics" may not matter much if you are trying to avoid sounding silly.

 

[DaveC426913]

Some things are impossible. Traveling faster than light for example.

-nitpick- This is a bit absolutist.

Some things seem to be impossible for massive objects as we understand them with our current physics. But we also understand our current physics is really relatively young.

The difference between "things that will never happen because absurd" and "things that can never happen because of the laws of physics" may not matter much if you are trying to avoid sounding silly.

Our laws of physics generally don't say things can never happen.

 

[hutchphd]

Our laws of physics generally don't say things can never happen.

I would beg to differ here. I think most of physics involves such limitations . Laws are sort of by definition prohibitions (the ten commandments come to mind) and we physicists do love our laws. Thou shalt conserve momentum. Symmetries, you know...

 

[berkeman]

Our laws of physics generally don't say things can never happen.

I would beg to differ here.

Let's try to stay on topic here, folks:

TL;DR Summary: How large does a mass of silica,iron etc have to be for gravity to got this mass to become a rock (asteroid ).

when a star goes supernova, does it eject out earth, mercury and mars sized chunks.

If you want to have a discussion about what the Laws of Physics say, that belongs in a new thread start. Thanks.

 

[snorkack]

Yes, I agree. Plasma, being ionized gas, does not come out in "chunks", but rather "bursts". If you breathe out on a snowy winter day, your breath would not be seen as coming out in chunks.

If it were a gas, would it be seen? Obviously it condenses, but into what - snowflakes? icicles? Same question about the plasma out of supernova - we have evidence in form of meteorites that it condenses within a century. How big ones then?