Category Archives: Space

Interview with Charles Miller

My Lunar vendor CSI just got a Space Act Agreement with NASA for their LEO Express system.

Sam Dinkin, Transterrestrial Musings:
Any reason other than testing that this system can’t be used for human passengers?
Charles Miller, CEO, Constellation Services, Inc.:
Yes. Unless the passengers plan to take up permanent residence in orbit, we would need to provide a way to return the passengers to Earth. In addition to a safe re-entry system, we would need to add some other systems that people tend to like, such as air and water and seats. There is a significant hit in terms of mass and financial cost to add all the systems are necessary to carry passengers. Nothing that has not been done before, but the canister that carries passengers will be much less cost effective for delivering cargo.

CSI studied concepts for recoverable canisters for NASA under in Phase 1A of our Alternate Access to Station contract in 2003-04. We have also looked at placing our canister inside RLVs, such as the Kistler K-1, for return to Earth. We received high marks from NASA’s AAS program for our ability to adapt our system to include a recoverable cargo capability.

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A Misapplication Of Rockets

Glenn (and Popular Mechanics) confuse the terms. As is pointed out in the article, rocket packs aren’t “jet” packs.

Remember the rules? If you want to cruise in the atmosphere, use an air breather. A rocket belt sounds cool, but it really makes no sense for this application. Rockets are for accelerating, and getting out of the atmosphere as soon as possible (or for traveling in space, if you’ve already done that). They’re not for tooling around near the ground, or for atmospheric transportation (rocket races being an exception, because it helps push the technology, and sounds cool). A true jet pack, though, would be actually cool, as opposed to merely sounding (and looking, when you see a pro do it at a show, for a minute or so) cool.

Pessimism

Charlie Stross isn’t very sanguine about the prospects for space settlement. My main criticism of his argument is that it seems to assume that all materials will come from earth, and that there are no resources available in space. When he writes, for instance:

Optimistic projects suggest that it should be possible, with the low cost rockets currently under development, to maintain a Lunar presence for a transportation cost of roughly $15,000 per kilogram. Some extreme projections suggest that if the cost can be cut to roughly triple the cost of fuel and oxidizer (meaning, the spacecraft concerned will be both largely reusable and very cheap) then we might even get as low as $165/kilogram to the lunar surface. At that price, sending a 100Kg astronaut to Moon Base One looks as if it ought to cost not much more than a first-class return air fare from the UK to New Zealand … except that such a price estimate is hogwash. We primates have certain failure modes, and one of them that must not be underestimated is our tendency to irreversibly malfunction when exposed to climactic extremes of temperature, pressure, and partial pressure of oxygen. While the amount of oxygen, water, and food a human consumes per day doesn’t sound all that serious

Software Testing Hard

Who watches the watchmen on software testing? SpaceX’s control issue might have been found with better testing, but the test case writer didn’t start with a big enough perturbation for the problem to appear. It’s also not clear that the tester software is sufficiently good to tease out problems with the control software. That’s especially true if the same people are writing the control software and the tester software.

The rest of the entry reads like technobabble from a movie like Failsafe. Nevertheless, this is the $64 billion question that can make SpaceX another of Musk’s successes or ground his Mars colonization plans altogether.

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