In article ,
(WaltBJ) writes:
SNIP
Size and Weight. Nobody was capable of putting a 30-40 ton warhead of
that size at those heights. Well, that, and atmospheric attenuation -
all the prompt stuff, and the heat, gets absobed pretty quickly by the
Atmosphere, and there'd be no fallout. There would, if you chose the
right height, be pretty severe EMP effects, but you don't need a
whopping huge bomb for that.
SNIP:
No fall out? The 100 MT was achieved by wrapping a multi-ton U238
jacket about Ivan. The fast neutrons from Ivan fission the U238 and
now you have multi tons of fallout added to Ivan. This of course is
the fission-fusion-fission
bomb in mega-size. I make the fireball from 100MT about 67,000 feet in
diameter.
using known sizes and the W^1/3 relation. Walt BJ

I should have said "relatively little fallout" Even with 20 tons of
vaporized casing, it's still a fairly small amount compared to the
contribution of even a moderate sized ground burst.

I was addressing Mr. Adam's contention that it was conceivable to, on
a clear day, depopulate the U.S with a set of 100 MT burts at 100+
miles in height. That's right out - the air's too thick, for those of
us on the surface.
Not that I'd want to be sitting next to one, mind you. IIRC, Ivan
scorched the RC-135 that was monitoring the test from some presumed
safe (ANd unintercepted) distance. I wonder what happened to the
Tu-95 that dropped it?

--
Pete Stickney
A strong conviction that something must be done is the parent of many
bad measures. -- Daniel Webster