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• Two Stage To Orbit - If done correctly, we can build one of these to operate like an airplane, instead of a munition. (See The Rocket Company for details. Single Stage To Orbit (SSTO) is right at the bleeding edge of our capabilities. But if we're willing to build big and build robustly, TSTO is doable with off-the shelf technology. (The fuel to get into space is not that much more expensive than the fuel to get a 747 over the Atlantic.)
• Modular Laser Launch - You can develop a laser module to launch a small unmanned test vehicle, then scale it up to launch useful payloads (5000 lbs) by building and combining multiple modules. When economies of scale kick in, you get launch costs that start to rival those hypothetical beanstalks.
• Rotovators that rendevous with a High Altitude Airplane - Again, it's hard to imagine a robust and reliable SSTO, but a Mach 12 high-altitude aircraft is much more reasonable. Also, a rotating tether that reaches only partly into the atmosphere and cancels only about half of orbital velocity can be built from materials that exist today! (Not unobtanium or carbon nanotubes.)
• A Lofstrom Loop - would also enable cheap access to space, and could be built with materials we have today. This is an arc that reaches above the atmosphere, suspended by the momentum of electromagnetically accelerated iron links. Vehicles would be launched into orbit by "stealing" a bit of the loop's momentum.

The rotating tether recycles energy from things going down. It also transfers energy in short times, like 20 minutes, instead of days. So you can do many payloads per day instead of days per payload. They don't need any amazing power transfer beams like the elevator. Really could be done today.

Check out spacetethers.com.

The Space Tethers will be built far sooner and are really much better. These can toss you into space fast so you don't fry in the radiation belts, recycle the energy from payloads going down into payloads going up, and be built with materials we have today.

The tether can get energy back from tourists returning to Earth. So if your main traffic is tourists going up and down, the tether energy is easy. Another fun trick is that if you had a series of tether in LEO, GEO, and Lunar orbit you could send stuff to the moon and send moon rocks (or other stuff) back to the Earth without needed to add energy. You just keep the total mass going each way balanced.

Because of this, orbital or lunar tourism will not take much more energy than suborbital rocket rides. So we should see it within the next 20 years.

I have a site, spacetethers.com that has info and a Java applet tether simulator. There is also lots of info at tethers.com

Private industry can not take up the flag for space exploration...

There is no profit in exploration. The only equivalent is R&D, and that typically only accounts for about 10% of a company's budget.

In order for that to happen [cheaper space flights] there must be central agency that focuses on this, and the agency must get government funding.

That would be the FAA.

Nasa needs to keep doing what it has been doing, and it needs to be able to explore other RnD efforts.

Just because you and 99% of the population associate NASA == Space Shuttle does not mean that it is true. Its name is Aeronautics and Space, not space, and thier budget is something like 20% for space IIRC. (BTW, NASA's budget is currently about the same ad DEA. Which would you rather fund?)

The only company the could do priovate space launch successfully would be microsoft, and even there 40+billion wouldn't ge them far.

Oh really. Take a look at this PDF that talks about private launches and how there has been a 15% growth in the market annually.

once private companies do start backing manned space exporation, we had be damn sure there is a controlling body for safty, and launches.

Again, there is no forseeable profit in sending a couple of people in space a couple times a year. Airlines have a steady flow of revenue and have trouble making profits.

For more info, there is an article discussing France's private launches. And one and another about Brazil. This looks like a new US company for space launches called space tethers. And this talks about how "Latin America Pioneered the Satellite Communications World".

I found on this site a mention of 1650 C for reentry temperatures, which seems low enough to make the material feasable.

I did my own google search on ward and starlite, and found this:

http://web.archive.org/web/20010407012348/www.char m.net/~dmg/mysteries/mystery1.html

The article mentions that NASA was investigating it, but the inventor wouldn't allow them to pursue it when they refused to sign an NDA.

I'm guessing the actual temperature on the material would differ slightly based on friction (or its coefficient of friction? I'm not a physicist), so its possible that the plastic still wasn't feasable for some reason. Then again, I'm told most of the heat is from ram pressure, so friction may not make a lot of difference.

Another explanation could be that the starlite plastic doesn't handle the extreme cold of space.

Or, NASA refused to sign the NDA because they thought he was a crackpot. Their view is somewhat supported by the site's claim that Maurcie Ward is no longer interested in his revoluntionary material, having given it up for harness horse-racing.

-Zipwow

Sir, it's bad form for a scientist to tell people that they don't know what they're talking about. If I am incorrect, exercise the option of teaching rather than insulting.

Anyway, since I don't want you holding (or refusing to hold your breath), I did a little research. For those, who are still interested, below is a wonderful set of links to websites that discuss the rocket equation. The second is my favorite. Enjoy!

Teachin' Science
Rocket Equation Applet
Wolfram

Michael.

Everyone talks about tethers, looking at the space-elevator notion. However, there's a reasonable (with simulations in applets) site promoting the notion of a rotating, orbiting tether that could be used either as a fuel-saving "last mile" (well, last 300 mile) trip to space, or alternately as an sling-shot that grabs the exiting craft in mid-flight and launches it balistically, like a trebuchet. Interesting, and they make a reasonable case, at least to one without the physics background to criticize. ;) i.