Re: [sl4] giant planets ignation - one more existential risk

From: Alexei Turchin (
Date: Sun Dec 14 2008 - 14:33:23 MST


1. The question of critical mass for Pu-238 is not principle to the
main question, because it was discussed only with connection if
Cassini could igmnate Saturn which is very unprobable. The main
question: is the detonation of the planet is possible at all; (But
fast neutrons doesn''t mean fusion neutron. for exmple, we have fast
neutron reactors, and they are not fusion reactors, but fission.

2. You mistakenly think that:
a) formula "E = p**2 X**3 T**30" cames from the article of
""Necessary conditions for the initiation and propagation of nuclear
detonation waves in plane atmospheres". Tomas Weaver and A. Wood,

and you don''t want even to look on that article because you don''t
like power of 30. (X is concentration, *** must be ** - power.)

b) that this formula is false.

In fact this formula cames from the book
Shklovsky: Stars: Their Birth, Life, Death,San Francisco, 1978
This book is also old, but even wikipedia agrees that:

"The triple-alpha process is strongly dependent on the temperature and
density of the stellar material. The energy released by the reaction
is approximately proportional to the temperature to the 30th power,
and the density squared. Contrast this to the PP chain which produces
energy at a rate proportional to the fourth power of temperature and
directly with density. This strong temperature dependence has
consequences for the late stage of stellar evolution, the red giant

Don''t belive in your knowleges! Use wikipedia! :)

But the question of possibility of thiple-alpha detonation of Jupiter
is also not main.

The main quetion is that observed level of diterium in the Jupiter is
only 5 times below minimal level which is needed for detonation

which is stated in the article which you don''t want to read beacuse
you don''t like power of 30 - and there power of 30 is not even

3. I had source there it was said that teller desigh would work if it
would be sufficiently large but I lost link. This is real bullshit.

On 12/14/08, John K Clark <> wrote:
> On Sun, 14 Dec 2008 "Alexei Turchin"
> <> said:
> > Use google!
> Read books. I'll let you in on a little secret, not everything on the
> internet is true.
> > US goverment think that Pu-238 may have critical mass:
> > "Updated Critical Mass Estimates for Plutonium-238"
> >
> The most important sentence in the entire article is:
> "Pu 238 is dependent on fast neutrons for criticality".
> I want to emphasize that this came from a paper that YOU recommended, it
> said "FAST neutrons" and fast neutrons come from fusion reactions not
> fission. So we are NOT talking about a chain reaction; how could we be,
> Pu238 is not even a neutron emitter, not of the fast variety nor even of
> the slow.
> You could have a solid sphere of Pu238 (or Uranium 239) the size of
> Jupiter and it would not explode without fast neutrons, and even then it
> would not be a chain reaction; a small amount of fast neutrons would
> only produce a small explosion, if you wanted a huge explosion you'd
> need a huge amount of fast neutrons. In this regard Plutonium 238 is no
> different from common cheap Uranium 238, indeed about 70% of the energy
> of an H bomb comes from the splitting of cheap Uranium 238, but only
> because it is hit by a HUGE number of fast neutrons caused by a nearby
> fusion reaction. Neither 238 substance can produce a chain reaction.
> > John, how would you explain that in 1979 scientists returned
> > to the question and wrote the article there they said that
> > detonation is possible if concentration of deiterium are higer then 1 to 300?
> I know nothing about this 30 year old paper, nor do I know anybody who
> does; and after you quote one of the equations in it I am not in any big
> hurry to learn more. You quote:
> "E = p**2 X***3 T**30"
> I have no idea what "X" is and I don't know what "***" means, presumably
> "T**30" means T^30, that is to say taking temperature to the power of
> 30. But if you see any equation that has a term like T^30 in it then you
> can be almost certain it is physically unrealistic. I can't think of any
> valid physical equation that rises ANY term to the power of 30! And my
> God, why are Fusion reactors so Damn hard to make? And why didn't
> Jupiter blow up a long time ago? The power of 30?!
> > Maybe you remeber Teller''s idea of
> > Simple Super bomb which doesn''t
> > work. It was a tube with liqiud deiterium,
> > and it doesn''t want to propogate detonation wave.
> It was a mixture of Deuterium and Tritium, the most fusion friendly
> substance in the known universe and it STILL didn't work. The gas giant
> planets are composed of common hydrogen, common helium, a slight trace
> of Deuterium and no Tritium. That is astronomically less fusion friendly
> then Teller's mixture, but you expect it to work anyway. I don't.
> > But why? Because it was too small
> Size doesn't enter into it. If the ocean is big and you're a long way
> from the bomb things are not extreme at all. If you're right next to the
> bomb things will get very hot but not super dense like they do in a H
> bomb.
> You need both high temperature and high density for things to become
> explosive, that's because even at 100 million degrees when Deuterium and
> Tritium collide most of the time nothing happens, they have to keep
> trying over and over and over before a successful fusion event happens.
> If things are super dense then all those retries can happen in a very
> very short time, but if things are not dense (and I mean dense) after
> the first failure by the time it finds another potential partner so much
> time has passed that things have expanded and cooled off.
> > In fact if Teller Simple Super would have widhth
> > of several hundreds meters it would work.
> Bullshit.
> John K Clark
> --
> John K Clark
> --
> - A no graphics, no pop-ups email service

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