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Interview With Dr. Bradley Edwards

Blogger Keith Curtis scooped us all with his recent interview of Space Elevator expert Dr. Bradley Edwards.

Like most of the rest of us bloggers, Keith's an amateur when it comes to interviewing. But compare his interview with NPR's interview of Dr. Edwards last June. It's Keith that gets the story.

BE: Even high up in NASA management, they won’t officially say it - but they have said it directly to me - that nothing substantial in space can be done with rockets.

I gathered from the rest of the interview that Edwards means that using rockets to escape Earth's gravity well is cost prohibitive. Rockets will continue to dominate propulsion and steering in space - for awhile.

BE: The Apollo program didn’t have a commercial endpoint. It set a goal of putting a man on the moon, which it was an enormous engineering effort. But the space elevator is a commercial effort. The Apollo, the Shuttle, the Space Station were never that.

This was a major theme of the interview. Space will remain little more than a place for governments to show off until space becomes economically feasible, and useful.

BE: If we are going to Mars just because it’s there, that’s not self-sustaining. It’s very likely that it will get killed once we’ve done it; then it will shut back down (just like Apollo) because it’s not self-sustaining.

...if China, South Korea or Europe plans out how to do it commercially, and for example gets infrastructures set up, then they’ll have a commercially self-sustaining enterprise which will spread out on its own, to the moon or Mars. That’s a real program, not pork.

So, if behooves us to be the first country that figures out how to make space profitable.

Edwards suggests that a space elevator will make space profitable in three areas: telecommunications, energy production, and controlling access to space.

BE: The company that operates the space elevator could then put up the telecommunications satellite, and become the telecommunications owner for the whole planet. Then they could put up solar-powered satellites and own the power producing capability for the planet. That’s a ridiculous amount of money and power involved. And if they really wanted to go hog-wild they could say “You know what? We are just going to take Mars! We are the only ones who can get there.” At some point the implications get crazy. So yes, there will be a pretty big return on it once it gets built.

[From earlier in the interview] With the space elevator, we can create a huge solar array. We’ll tap into this energy, and it won’t run out. We won’t have to deal with oil glitches and stock market glitches and potential environmental glitches.

I wonder if space-based nuclear power wouldn't be easier to implement than a massive solar array. In space you wouldn't have to worry about being "clean." And there's plenty of nuclear fuel on the Moon. But getting the fuel from the Moon might be expensive.

BE: I’m not a big fan of the lunar elevator because there are a lot of complications and fewer economic reasons. Asteroids are a lot easier to put elevators on. We can do that with current materials if we have an economic reason to do it. The moon is a little more difficult because of its slow rotation.

You need rotation to overcome gravity, and the Moon's gravity is only 0.1654 gee - about 1/6 Earth's gravity.

But the Lunar rotational period is 1/27th that of earth. I'm guessing that means that a lunar elevator would have to be quite long. The longer the elevator, the more likely that Earth's gravity will become a problem.

I remain more optimistic than Edwards. Several times during the interview Edwards seems to discount the commercial value of the Moon. But, as Keith pointed out, Edwards own book mentions the potential of Helium-3 - a valuable nuclear fuel found in abundance on the Moon. If the Moon has any value, and if a Lunar Elevator is possible at all, I'm convinced it will be built.

Obviously, Edwards is bullish on the feasibility of a Space Elevator - from Earth.

BE: ...two hundred tons is like the size of a large commercial aircraft. We can build a climber that size, and a ribbon that will hold it. It’s all things that can be done. Ramping up to that size is a matter of will; there aren’t any physical constraints...

133827main_lander_sm.JPGKC: I think this picture summarizes why we shouldn’t follow NASA’s vision. There are a couple of guys, a cute little space ship, and an American flag...

BE: Or, we can have a city up there. I sent a proposal to NASA which cut the cost of the moon-Mars initiative in half, and what it ended up being was a settlement of 100 people on the moon and Mars with all kinds of infrastructure and supply depots and everything else - the money wasn’t being spent on the launches.

Yeah. Been there, done that. All of that, 30 years ago.

Make sure to read the whole interview. And here's Dr. Edward's outstanding space elevator article at The Spectrum.

And here are the recent space elevator posts at The Speculist:

The Imminent Arrival of the Space Elevator

Space Elevator Update

Getting to the Moon

Arthur C. Clarke's New Space Elevator Prediction


Asteroids are a lot easier to put elevators on.

I've been thinking about industrial (as opposed to scientific) missions to asteroids for a while and one of the first things I think should be built with local materials is an asteroidal space elevator.


And now that our idea of space elevator has changed from a tall metal tower to a carbon nanotube ribbon, setting up an elevator on any spinning rock becomes feasible.

Get into orbit, spool the elevator ribbon down to the surface and attach at the equator. Your ship serves as the counterweight. Some of these asteriods might not even require that the elevator ribbon be reinforced by climbers.

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