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Hey, man, welcome to the 21st century. Private companies do space stuff now, too. Since when do we need to get everybody to "work together" to do such a thing? Anyway, we could create a station faster than it takes most proposals to get written these days by using approaches like this one.

And fwiw, the ISS is famously a boondoggle whose costs are grotesquely outscale in no small part because of how well it worked to have "each nation...work together". For the amount of money and time that was blown on the ISS we could have gotten a colony built on the moon by now. Seriously. Maybe two of them.

So if you want to see us working together like that my question becomes, so, what are YOU doing to help, cobber? It's real easy to say what others should or could do, not so easy to do it.

Cool.

And googling around after posting that I found your interview with David Brin and Bob Forward, and also an online copy of Brin's Tank Farm Dynamo... which for some reason I had remembered as being by Robert Forward. Maybe that was in a parallel universe...? :)

I gotta say, the internet's getting pretty damn good at instant gratification. I can't recall the last time I went downtown to the library... no, I can, it was at least 10 years ago, and I was looking for a copy of the August 1976 BSTJ.

Found it, too.

What schools teach you about Mao in "a positive way"?

China's "Great Leap Forward" around 1960. The typical estimate given for the number of people who died is generally placed around 30 million people.

When Communism was strong (and these bodies were named) China certainly had a very strong social welfare program

You mean like the social welfare programs that starved 30 million people to death?

China's move away from Communism trough free market reforms, and its expansion of exports to the US, has lead there to be about 200 million fewer people in China living on under $1 per day now than in 1990.

I'm no apologist for China's continued lack of human and political rights, but at the same time at least the government appears to be leading economic growth, which is much more than I can say for Cuba or North Korea (or places like Zimbabwe).

The text of Tank Farm Dynamo is online.

Isn't it about time they switched from assembly to C ?

Yes, as long as it's Shuttle C.

Here's another recent article. The Shuttle C concept was based on the idea of replacing the orbiter with a third-stage rocket, forming a highly effective heavy-lift launch vehicle. Great for humans to mars, among other things.

Long term, you're probably right -- the cost of steel, copper, aluminum for the transmission lines goes down. That'd be competing with the obvious pressure to move power generation closer to the users, which would be balanced out by capital cost and capacity limits -- you tell me what they are and we can make a guess where the breakeven would be. When I was thinking about it, it was with Bussard's notion of a "Farnsworth fusor" (see, eg, here, here, or here, or the Google search here.)

This leads to a notional reactor that's 5 meters across, and yields 10 gigaWatts (6600 Amps at about 1.5 megavolts DC, and be damned to Tesla!) using proton-boron fusion.

(Note: I'm not a physicist, and I'm not a power engineer, so don't come after me if you don't like these ideas.)

The whole thing is basically a big empty conductive sphere with some accessories, so it shouldn't cost more than about $1 million, so we're definitely in the neighborhood of pennies to mils per megawatt-hour. But it's almost an embarrassment of riches: how to you deal with a city of, say, 5000? A million bucks is a feasible investment for a city that size, but what do you do with the 9.75 gigawatts left over?

Having said that, I can't find the article that laid out the particulars. I'll keep looking, and post something if I find it.

The basics behind the statement are twofold: first, the shuttle ET has between 5 and 20 tons of fuel left when it gets ejected from the orbiter. Second, the shuttle has to make a specialized maneuver right before it ejects the ET that ensures that the ET is headed down the correct insertion path for its death descent into the atmosphere. If it continued along a ballistic launch trajectory, not ejecting the residual fuel, extra cargo capacity could be achieved.

While you're waiting for me to get back to you, check out Chris Fitch's excellent ET page at this link.

Regards,

JD

I'm hanging my hopes on Armadillo Aerospace. Looking forward to them trying out for the X-Prize, and their approach of documenting everything on their website via pictures, video, and blog-type updates is great. I hope they succed - we need a commercial manufacturer of rockets that doesn't need to charge a premium to support overhead of non-space units.

Think cheap dumb boosters - the kind of vehicle the shuttle should have been before it was hijacked into being a commuter service. Keep in mind, we don't need to throw away the STS infrastructure (crusty as it may be.) Just replace the orbiter with a larger unmanned payload module, keep the external fuel tank and boosters. Then, build dozens of payload modules, external fuel tanks (screw the insulation - which is needed to keep ice from forming on the fuel tank, make the payload module disposable), and boosters, in order to get economies of scale. Since there's nobody on board, we don't have to worry about having 99.999999% reliability, nor do we have to waste money on life support.

Just so you know, this payload version of the shuttle already exists on paper, as one of the alternate configurations of the shuttle combo - known as the Shuttle C.

If you're curious about other never-built shuttle designs, visit http://www.abo.fi/~mlindroo/SpaceLVs/Slides/sld022 .htm.

Or, we can buy Russian rockets wholesale, if we don't want to invest in our domestic rocket industry. Just don't put pilots in cargo vehicles - there's no point! If you want to send up pilots, put them in spacecraft specifically designed to deliver people... survivable spacecraft.

You don't need to tether the end, you can still get some very healthy benefits with a partial elevator. Deals with a lot of the security issues too. Cargo craft only need to fly to the low end and ride the rotation to the top where they can slingshot off. Using the Earth's magnetic field and solar power means it's self-stabilising too. More detail and better writing at; Free David Brin Short Story

It costs quite a bit of money just to put a pound of mass into orbit. Just looking for a quick ballpark, I found http://www.orbit6.com/et/ngfido94.htm which asserts:

Launching the 80 tons of fuel into orbit will cost about $150 million? for one launch of a Shuttle-Derived HLV (or its Energia equivalent) or $1.5 billion if Titan IV vehicles (5 Titan IV's at $300 million each) are used (see how cost-effective developing a Heavy-Lift vehicle would be. Without a Heavy-Lift vehicle it would cost ten times as much to launch 80 tons of fuel to LEO: $150 million versus $1.5 billion. An HLV would pay back its development costs in short order).

So it's about US$1.875M to launch one ton of mass into orbit (best case.) Therefore one ton of, say, iron in orbit is worth whatever a ton of iron is worth normally, PLUS some fraction of US$1.875M.

If you're building things for space, the best way to go is to build them IN space, which should cut their cost dramatically. We shouldn't forget about reusing the shuttle's bigass tanks, which NASA says they can do for free, and supposedly will do for anyone who is willing to do something responsible with them. We should be thinking of ways to use those tanks to do something clever WRT space-based mining, because they're cheap. Perhaps one should build some sort of machining facility, and a smelter; Having done that it should be possible to make ISS parts or similar. This would save huge piles of money, because you only have to lift the most specialized components.