Added 2 new A* pages:Well I was going on about the successful launch/landing test of the private SpaceX "Dragon" capsule via their "Falcon 9" rocket last week, and it turns out they put a video of the launch on YouTube:
https://www.youtube.com/watch?v=Q-ci9xIgNZM
Kind of neat because there's a camera on the rocket, facing backwards, so you can see the ground getting smaller and smaller, then the thruster stages falling away, and (best part) the nozzle of the second stage thruster heating to red hot, then cooling almost immediately when the engine cuts off. And here's a fun game: count how many times the controllers say "nominal." :P
NASA also made a video of the launch—it doesn't have a on-rocket cam, but it does have the launch in hi-def. Although really once you've seen once rocket launch, you've seen them all—except for the ones that go appallingly wrong.
While I was double-checking that "nozzle" was the correct term for that bell-shaped thingy around a rocket's exhaust port, I came across aerospike engines, which instead of having a bell-shaped nozzle have a sort of inverted bell spike shape; the idea is that at low altitudes—where you have high atmospheric pressure—the atmosphere acts as the other side of the bell, and eh anyway you end up getting better fuel efficiency or something. Okay that's boring, but the point is they look neat; here's a "linear" type
image by NASA (source)
and the really spiky "toroidal" type
image by NASA (source)
which kind of reminds me of certain old sci-fi ship styles from like the 50's or something, of which I can't seem to find a good example right now. :P Anyway, funky look.
That linear one is interesting too because it was developed for the X-33 experimental space plane by Lockheed Martin, to do basically what the SpaceX Falcon 9/Dragon combo is doing, except it was going to have all its fuel on-board—which I guess is why they were messing with aerospike thrusters, to get the best fuel efficiency—so it wouldn't have to use disposable thrusters for launches.
Remember how last week I'd use 10% as the approximate pre-fuel weight of the ship heading toward Paralt here in A*? Well turns out that for the X-33 they did indeed figure that the ship without fuel could only make up 1/10th of the total weight—and they just couldn't construct a fuel tank both light and strong enough to fit that parameter. So the federal project was canceled in 2001 after well over a billion dollars had been spent on it by NASA and Lockheed Martin.
Aerospike technology has actually been around since the '60s, when a company with the awesome name Rocketdyne was the major supplier of rocket engines for the US space programs, and this continued up into the '70s, when they were selected to supply the Space Shuttle's main engines—and aerospike designs were considered for that.
Various design difficulties have held aerospike thrusters back from actual practical use, but Lockheed Martin continues to tinker with them. Will their time ever come?
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Ooh and I keep forgetting to pimp the updates I'm doing to my oft-neglected humor comic "One Off" this week. The third and last (for now) one will be going up shortly, here's a preview and link to the One Off site:
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