Uranium Fissioning: Is Star Formation Possible?

[chgol5270]

Just curious if uranium could gather in enough quantities so that it's gravity will keep it from blowing apart or will critical mass start a chain reaction and prevent this configuration into a "fissioning" star

 

[jfizzix]

I would think the laws of physics don't forbid this, but considering you need a critical concentration of Uranium 235 to allow a chain reaction to take place, there is probably no gas cloud in the universe pure enough to condense into a weapons-grade uranium star.

 

[Danger]

Uranium is by no mere coincidence considered a "transuranic element". The natural fusion process in a star stops at the point where iron is the end product, because there's nothing that you can do to make iron fuse. (It "refuses to fuse", it you'll pardon the term.) The only way for the process to proceed is through neutron-capture transmuting the iron into heavier elements, but even then they pretty much have to then break into smaller components which can then resume fusing.
I'm not expert in this area, but that's my general take on it.
(I'm deliberately ignoring the term "fissioning star" because that is self-contradictory and can't exist.)

 

[OmCheeto]

Uranium is by no mere coincidence considered a "transuranic element". The natural fusion process in a star stops at the point where iron is the end product, because there's nothing that you can do to make iron fuse. (It "refuses to fuse", it you'll pardon the term.) The only way for the process to proceed is through neutron-capture transmuting the iron into heavier elements, but even then they pretty much have to then break into smaller components which can then resume fusing.
I'm not expert in this area, but that's my general take on it.
(I'm deliberately ignoring the term "fissioning star" because that is self-contradictory and can't exist.)

I guess we'd have to redefine what a "star" was, or come up with a new name for such a thing.
We did have a naturally occurring nuclear reactor in Gabon a while back.
And I've just read a couple of articles claiming there might be a multi-terawatt sized natural reactor at the core of the earth. (ref. below)
Didn't someone named Dyson talk about an inhabitable sphere surrounding a star?
Perhaps we live on one, only, it's inside-out, and the star is operating backwards.
I nominate "rats" (star backwards), as the new name of our new type of reverse star.
It shall stand for RAdiative Terrestrial Source.

:)Deep-Earth reactor: Nuclear fission, helium, and the geomagnetic field
Nuclear Fission Confirmed as Source of More than Half of Earth’s Heat

 

[chgol5270]

Uranium is by no mere coincidence considered a "transuranic element". The natural fusion process in a star stops at the point where iron is the end product, because there's nothing that you can do to make iron fuse. (It "refuses to fuse", it you'll pardon the term.) The only way for the process to proceed is through neutron-capture transmuting the iron into heavier elements, but even then they pretty much have to then break into smaller components which can then resume fusing.
I'm not expert in this area, but that's my general take on it.
(I'm deliberately ignoring the term "fissioning star" because that is self-contradictory and can't exist.)

Im talking about uranium created during supernovae events (your post suggests this happens during the normal fusion process in stars which I am not aware of) and while the concentrations might not ever get to a point that it condenses i am just curious if there is anything that would prevent this configuration other than the resources needed

 

[jfizzix]

It may also be, that even if you had a cloud of weapons grade uranium vapor, it might never condense into a star since the density and temperature where fission takes place is much lower than what's needed to make the star undergo fusion. The energy released during fission at these low densities would probably blow the cloud apart before it could condense enough to overcome that force. I have no calculations to back this up though, so take it for what it's worth.

 

[Danger]

I guess that I was too focused upon the term "star", which is defined as a fusion structure. Sorry. As for a massive fissioning body, I agree that the violence of the reactions would scatter the condensing cloud as quickly as it accumulates. It could end up being something of a "bungee bomb". In a normal star, the density needed to initiate fusion isn't reached until gravity is already firmly in charge.

edit: It isn't something that I would want my planet to be orbiting. oo)

 

[OmCheeto]

I guess that I was too focused upon the term "star", which is defined as a fusion structure. Sorry. As for a massive fissioning body, I agree that the violence of the reactions would scatter the condensing cloud as quickly as it accumulates. It could end up being something of a "bungee bomb". In a normal star, the density needed to initiate fusion isn't reached until gravity is already firmly in charge.

edit: It isn't something that I would want my planet to be orbiting. oo)

"Bungee bomb"!? Did you just make that up? It does seem like an appropriate name though.
I also think this would make a great math/physics/computer science simulation homework problem.

But, I agree with you. I can't imagine a fission type star having a Goldilocks zone. It would just be, um, a bungee bomb.

ps. I'm now "following" you too, in case you haven't noticed.

 

[Danger]

"Bungee bomb"!? Did you just make that up?

Yeah.
Should I copyright it?

 

[OmCheeto]

Yeah.
Should I copyright it?

Yes, you should.

Though I don't think you'll live long enough to see any royalties from it.
They're still pissing and moaning about the "physics" of Interstellar.
Idiots... It was a movie... Where's that "1st world problems" thread...

 

[Danger]

 

[chgol5270]

It may also be, that even if you had a cloud of weapons grade uranium vapor, it might never condense into a star since the density and temperature where fission takes place is much lower than what's needed to make the star undergo fusion. The energy released during fission at these low densities would probably blow the cloud apart before it could condense enough to overcome that force. I have no calculations to back this up though, so take it for what it's worth.

I figured that would be the case thanks for the input