This idea is a significant part of Anathem by Neal Stephenson.
Anathem was so chock full of interesting ideas, too bad the last parts of it were so rushed (or at least felt that way to me).
More Bounce to the Ounce
31–40 of 66 posts
Re: More Bounce to the Ounce
#32Re: More Bounce to the Ounce
#33This idea is a significant part of Anathem by Neal Stephenson.
Also featured in the 1985 novel Footfall by Niven and Pournelle.
Re: More Bounce to the Ounce
#34This is a really enjoyable read. Majiec is a great writer and speaker. A breath of fresh air compared much of modern blog/essay content.
Where modern is post 2000 not 2020! https://idlewords.com/2006/04/argentina_on_two_steaks_a_day.... https://idlewords.com/2014/07/sana_a.htm
I revisit https://idlewords.com/2007/04/the_alameda_weehawken_burrito_... every few years.
Also a big fan of https://idlewords.com/2010/03/scott_and_scurvy.htm
Re: More Bounce to the Ounce
#35Wild cowboy ideas of yore. Will we ever be able to make it safer to use on earth or would we save that for a moon base -get to the moon and from there blast away with these atomic fahrting machines…
With any luck, by the time we're serious about sending big spacecraft out and about we'll have figured out a workable fusion drive. You'd still need to launch them from space since they're a little spicy from a "don't stand downwind" perspective, but unimaginably better than using nukes against pusher.
There are other possible fission options that don't involve detonating actual bombs out the back of the rocket: https://en.wikipedia.org/wiki/Nuclear_propulsion#Spacecraft
I'm a fan of the nuclear lightbulb myself: https://en.wikipedia.org/wiki/Gas_core_reactor_rocket#Closed...
Sometimes I think that while it may be appealing to mine gold or platinum or whatever out of the solar system, what people really need to figure out how to do is mine uranium. While I could advocate with a straight face that maybe we need to freak out a bit less about lifting the occasional few dozen pounds of uranium into orbit, and point out that more radioactive material has already been launched than people realize, it is fair to observe that we probably can't afford to make lifting hundreds of pounds of fission fuel into orbit the sort of routine event it needs to be to really have a space civilization. One of the biggest major issues with any sort of space habitation is access to dense energy sources. You can smooth over a lot of other problems and get a lot more slack in the system if you have a lot of energy available to play with. Part of the challenge with current space technology is that you start out on the very edge of feasibility as it is.
Re: More Bounce to the Ounce
#36Re: More Bounce to the Ounce
#37Article briefly talked about delivery, which is tricky to do precisely at best of times, but didn't really mention how to address delivery into a nuclear blast. Hundreds of meters behind the craft about once a second doesn't seem like it would be enough time for the blast to clear so would get in the way of sending a new capsule backward. Anyway I'm sure it's just an implementation detail
A lot of the work was done to a design point of 0.25 seconds, and Dyson's book says the issue there wasn't the blast clearing, but just being able to move the machinery fast enough. I kind of share your puzzlement; I can see the blast clearing this quickly in space (the debris moves at tens of thousands of km/sec) but not in the atmosphere.
The blast clears that quickly in the atmosphere because the shockwave and debris move at-or-faster-than the speed of sound, so a few hundred meters is tenths of a second or less. You sit inside the mushroom cloud, of course, but the important part is gone quickly.
The Rapatronic camera was used to take these kinds of pictures, and you can see that the actual blast front is around 20 meters across after 1 millisecond (!!) https://en.wikipedia.org/wiki/Rapatronic_camera
Re: More Bounce to the Ounce
#38I think NERVA and its Soviet equivalent RD-0410 were much more practical and plausible. Unlike Orion which was complete vaporware, both these projects reached the ground test prototype stage.
Re: More Bounce to the Ounce
#39I think NERVA and its Soviet equivalent RD-0410 were much more practical and plausible. Unlike Orion which was complete vaporware, both these projects reached the ground test prototype stage. https://en.wikipedia.org/wiki/NERVA https://en.wikipedia.org/wiki/RD-0410
NERVA / RD-0410 are basically like chemical rockets but better (maybe 800s specific impulse, vs. 300 for a chemical rocket). In contrast, Orion was 6,000s to maybe 100,000 theoretically.
Re: More Bounce to the Ounce
#40Earlier quoted context omitted.
Anathem was so chock full of interesting ideas, too bad the last parts of it were so rushed (or at least felt that way to me).
I always describe it as an excellent 300 page novel crammed into 900 pages.
This is the clearest explanation of why I never really liked Stephenson.