Nuclear explosions in space.
First and foremost, I have no education or experience in space sciences beyond my affinity of following those who do. Please think twice before saying "won't work" (something like, the old school scientist will say it is impossible, and the new school scientist will prove him wrong).
I understand that the US and Soviet Union both began work on spacecraft propelled by nuclear explosions. Here is an excerpt from the Wikipedia article on Project Orion:
The vehicle and its test program would violate the Partial Test Ban Treaty of 1963 as currently written, which prohibited all nuclear detonations except those conducted underground, both as an attempt to slow the arms race and to limit the amount of radiation in the atmosphere caused by nuclear detonations. There was an effort by the US government to put an exception into the 1963 treaty to allow for the use of nuclear propulsion for spaceflight, but Soviet fears about military applications kept the exception out of the treaty.
Perhaps it's because I grew up after the collapse of the Cold War, but these types of spacecraft seem to be our best bet for manned exploration of the solar system. Every time I read about lassoing asteroids for their resources (like Ceres), the argument is always brought up that it would take an enormous amount of energy to move and stop a body of that size.
Nuclear explosions continue to pop up in my brain as solutions to these problems which may at some point have profound impacts on our current resource limitations in space, and would also allow for launching lighter spacecraft with our conventional cave-man methods.
Right now some Russians are making the case for nuclear powered spacecraft, which is promising to me since they seem to have been the party that raised the most objections to them in the past.
What do you think about this? What are the limitations and risks? Do you think there is harm in making an exception to the Outer Space Treaty for nuclear spacecraft? What sort of implications might this have for moving around large bodies (perhaps moving small water containing bodies to intercept a conventional rocket to Mars for ISRU)?
Posted Mar 6, 2011, 10:21 PM UTC
I am all for Orion-type spaceships, but moving Ceres around is an overkill of (literally :) astronomical proportions. To put things in proportion, a single small, nickel-iron asteroid one kilometer long probably has more metal than everything that has ever been mined by Humanity along all History; and a single comet the same size would have many times the water supply (in the form of ice) of a large city. So, we don't really need (or can imagine an application for) moving around a thing the size of Ceres, which is billions of times larger and by the way is classified as a dwarf planet, not an asteroid. Also, not even all of the existing atomic bombs would make some noticeable change in Ceres' orbit; I have not run the numbers, but intuitively it seems like trying to move a watermelon using a firecracker, in the best of cases...
Noted. The example I used of moving an asteroid was more of a thought on the potential Δv power of nuclear explosions. As much as a thermonuclear explosion might be useful for moving enormous bodies at low velocities, one could move a smaller vessel at a much higher rate. I really think nuclear propulsion of the Orion-type would be a great way to reduce the weight of launching manned long-distance spacecraft. I was just trying to tie in ISRU doctrine with nuclear propulsion. There is always, of course, the talk about the risk of catastrophic failure spreading radioactive material across populated areas, but what about the hundreds(thousands?) of ICBMs in existence? All it would take is one failure and a "friendly" fire accident would be devastating.
This whole talk makes me love/hate the new direction of NASA. On one hand there is a glimmer of hope that the free market would drive down the cost of space travel, but on the other hand we haven't sent a human past LEO since the Apollo missions. I wonder if there would be an efficient way of giving universities/academia more control over the space program.
Ah! I forgot that! Thanks for the correction.
Also, is there a better/proper name for Orion-type spacecraft? How about Controlled Fission/Fusion Powered Spacecraft? CFPS (Sounds like sip piss)
Nuclear Pulse Propulsion (and NPP is a better-sounding acronym, I think :)
It depends on what you think is the most important goal of the space program. Most academic programs would probably favor small, unmanned spacecraft for studying the solar system. Human space exploration is much more expensive.
Global iron production in 2009 was 2240 million metric tons. A cubic kilometer of iron ore would be about 5 billion metric tons, or about 2-3 years of 2009-level iron ore production.