The high risk frontier

The Space Review ^ | 02/07/05 | Sam Dinkin

[KevinDavis]

In The High Frontier: Human Colonies in Space, by Gerard O’Neill and published in 1977, a very exciting case is made to take humanity into space to stay. With plentiful and reliable sunlight, good access to the asteroids, Earth, and the Moon, L5 has a bright future. With almost 30 years of hindsight, much of the utopian vision has been validated even as some of the technologies remain 30 years away (see sidebar).

The High Frontier tells us more about the 1970s than it does about human space colonies. The social, political, and economic case to emigrate is nearly identical to the case made in the Club of Rome report that says that we are going to run out of everything by the year 2000. O’Neill waxes poetic about the cost and capability of the latest, greatest lifter, the space shuttle. An orbiting L5 station is offered as a cure for inflation. Even the easier attitude toward sex is present: “can one imagine a better location for a honeymoon hotel than the zero-gravity region of a space community?” I am much more controversial today even raising the subject, much less saying that honeymooning couples would probably prefer the attraction of gravity.

[KevinDavis]

[Mamzelle]

(snort)

[nuke rocketeer]

The bottleneck is cheap lifting capability from ground to LEO. As long as we have to use rockets, both deals on a large scale won't happen, no matter how much we space cadets want it to.

[unlearner]

From what I've read, we are probably only 10-20 years from the ability to build space elevators that could overcome this financial hurdle.

[nuke rocketeer]

Either elevators or laser launchers

[unlearner]

How do "laser launchers" work?

[nuke rocketeer]

Larry Niven has given excellent descriptions in "Footfall" and other novels, but, essentially, you have a vehicle with a large end bell on it, kind of like an over sized rocket nozzle. When you hit it with a high powered laser, the superheated air acts as the propellant mass. It can be combined with an electromagnetic rail launcher. The laser stays focused on the end bell until it reaches orbital velocity. Everything except for small maneuvering thrusters is pure payload.

[unlearner]

Very interesting. I have been writing a story set in the future that includes a space elevator and space station.

In my research I did not come across anything like this.

I guess I need to check it out.

[nuke rocketeer]

Go to this link on Space.com

http://www.space.com/businesstechnology/technology/beamed_propulsion_021105.html

[nuke rocketeer]

And this one

http://www.cnn.com/TECH/9709/24/laser.rocket.reut/index.html

[unlearner]

Thanks. I have bookmarked the links to read shortly.

Very cool stuff.

[techcor]

Actually "coherent nuclear resonant scattering" is what will do it. The energy will be stored in a crystal then released when a magnetic field is applied. The technique you described was also used in a book called Millenium Foundation ( I think) by Marshal Savage. But the C.N.R.S. way means you can take it with you and it is going to be so safe even the environmentalists will have hard time complaining about it.

Another way would be to use americium 242m but it wouldn't be as safe.

[techcor]

Google "coherent nuclear resonant scattering" sometime and think of the implications.

[unlearner]

Thanks. I'll check it out.

[nuke rocketeer]

Looks interesting. Also looks like you posted something on this last January. It also looks like it is only at low power applications right now. I would bet that it will take 15-30 years to get it up to where it will be practical. With the weapons lasers the AF has now I think the laser launchers are the best near term bet. Also, it does not look like it will work for ground to LEO anyway, since it uses XRays, a little too much dose for those nearby.

[techcor]

15-30 years is probably correct. The laser rocket just made it to 71 meters and the estimate is that maybe in 5 years there may be a launch. Cool stuff. The incidental x-ray radiation may not be as much as you are estimating. It is after all a coherent beam shooting away from the passenger area. Basically a laser powered particle accelerator.
It may be low power now but I always post about americium 242 m because metastable nuclear isomers have incredible power. The Am-242m was estimated to be 100 times as powerful as plutonium. Also, the C.N.R.S. technology could be coupled with a photovoltaic cell geared for its' wavelength to create a powerful energy storage cell. As well as applying it to a laser based missile defense.
I figure it will first be used in "rocket chips" to power small satellites to Mars.