your recent comment concerning Boron and H-Bombs got me going—https://www.nextbigfuture.com/2012/02/which-is-cheaper-per-unit-of-energy.html
”THE thing that scuttles this isn’t the cost of the nukes, nor the added-load of nuclear fallout in the atmosphere (a political problem more than anything), but the consequence of the nuclear explosions to the payload. They would be positively drenched in neutrons with every shot. Now, one can go all yada-yada “boron”, etc … assuming that one might be able to absorb most of the neutrons.
Aux Contraire, me hearties. Neutrons, especially in “spikes” are really good at lighting up absorbers such as boron into resonant states that no longer absorb (on nanosecond time-scales) more neutrons.
What you’d get by the time the big tub got to space … is a highly radioactive wastebin of heavily transmuted “stuff”. Electronics would be fried. Metals would be permanently radioactive. This is not what would be “the point”.
Further, instead of wishfully thinking about using megaton-or-larger devices to get around the cost, please recall that if small-kiloton blasts (0.5 to 10 kT) could barely be sustained by the pusher-plate due to blast-spallation effects, then 100 MT is right out. There are no known materials that wouldn’t just vaporize to plasma in 10-meter-thick layers at modest proximity to such blasts. The 1 km wide, 100 m deep pit left after the air-burst of the Tsar Bomba at only 50-60 megatons wasn’t only “compressed dirt”. nearly half the mass was vaporized entirely. Instantly.
The whole idea is an intellectually stimulating thing, but a practical nightmare. And that’s the problem. Not to mention the elephant-in-the-living room.”
1000
|
m (dia)
|
20
|
deg (repose)
|
0.35
|
‘= radians
|
342.02
|
m (pit)
|
0.34
|
ratio (pit/dia)
|
44,770,332
|
cu m (crater)
|
1.27
|
kJ/(kg*K) (sp heat, basalt)
|
500
|
Hv (J/g = kJ/kg) (entropy of vap)
|
3,300
|
delta T (to vaporize)
|
4,691
|
kJ/kg total
|
100
|
m deep vaporized
|
4.62%
|
amt
|
3.5
|
spec grav
|
7,243,177,838
|
kg vaporized
|
3.40E+016
|
J
|
55
|
MT bomb
|
2.20E+017
|
J/yield
|
15.44%
|
yield to vaporization
|
The factor x^2.5 (not ^3) was used for figuring volume of vapor-layer. Yes, pulled it out of my tush, but it makes sense too: a radial heat-intensity profile at ground surface wouldn’t be unlike the same cone profile that defines the crater itself. Not as deep, not as wide. The final 15%-of-bomb-to-vaporize-rock seems pretty nominal. Most energy would dissipate outward, not downward. But clearly too, most downward energy would impinge on friable rock, which would rapidly (nanoseconds) vaporize, resulting in plasma, which turns out to be nicely transparent to infrared and optical energies … necessary to vaporize more rock. Speed-of-light gets in the way, but but there aren’t good scattering mechanisms. So, it gets absorbed. The IR/visible opacity (transparency) thing ensures that once vaporized the plasma doesn’t heat much more. Useful.
[A2] boron. “Fresh for each pop” isn’t a bad solution. The amount though has to be pretty convincingly large. All that extra mass … does Orion’s equations still work? And what of all that nuclear ash? Damned inconvenient. Let’s just get behind mass-throwers, shall we? No fallout, the same “nuclear power” [at small power stations along the launch site] gets the work done, etc. Use something reasonable [100G] for nonbiological launches and [8G] for bio. Or “water filled launches” (this works well, even up to 15G for people)
Maybe the brown curtain like radiance in this movie still around the fireball is rock vapor boiling away? Doubtful but intriguing. The movie below shows a quick action view.
Note that the Wilson Cloud Chamber Effect shocks atmospheric moisture into visibility so most of the clouds you see after that will not be candidates of interest for this study.
Location of test: |
If you liked this article, please give it a quick review on ycombinator or StumbleUpon. Thanks
Joseph Friedlander is a thinker in the pattern of Herman Kahn or David South, who takes a theoretical construct and reduces it to detailed scenarios for action, with an emphasis on the immediately achievable and the practical that can be settled for in the very near term as a foundation for greater achievements later on.
Joseph has a degree in business, certificates in computer aided design, tool and die work, information science, and other technical areas and wide background familiarity with astrophysics and chemistry.
His reading is wide-ranging (some would say encyclopedic). Among his favorite authors are those who concentrate on the links between industry, government and military, society and prosperity, in particular Jane Jacobs, Seymour Melman, Herman Kahn, and Kevin A. Carson.
Joseph is an inventor and consultant who writes and speaks often on space industrialization and settlement as well as future industrial possibilities on Earth and the ways these things could change our lives. He is a member of the World Economics Association.
He authored In Praise of Large Payloads for Space, Joseph Friedlander’s Thoughts Inspired By Alexander Bolonkin’s Writings On How To Catalyze Innovation And Technical Progress, Hyperwealth and Alternative Futures, Tyler Cowen’s “Great Stagnation” — Joseph Friedlander Perspective and Thoughts on Related Subjects, What was the best way to use the Saturn V to reach the Moon — in retrospect?, A summary of Dr. Bruce Cordell’s 21stCenturyWaves.com Maslow Window Model, and The Friedlander Cold Crown — A Cold Trap For The Lunar Poles — Solid Oxygen For Lunar Capture And Export.
Read his LinkedIn profile.