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wumpus

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About wumpus

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  1. But even the spaceless parent company isn't the beer company. How disappointing. They are a "American, privately held aerospace and national security contractor specializing in aircraft modification and integration, space components and systems, and related technology products for cybersecurity and Health", according to the infallible wiki.
  2. When you set up a redundant bidding system (which is especially smart as one of the original commercial resupply contract winners failed and dropped out), you tend to get an oversupply. Which is kind of the opposite of letting NASA/Congress micromanage a launch project.
  3. Elsewhere I posted this (thus the fission/fusion notes. It was in a fusion thread): In other news, NASA is paying BWXT ~$9.4M for one year's development of a nuclear thermal rocket. Granted, I'm sure they are using fission, but it seems more likely than some powerpoint slides will progress quickly towards fusion. https://arstechnica.com/science/2021/04/rocket-report-spacex-abandons-catching-fairings-ula-bets-on-upper-stages/ It appears to be a separate contract.
  4. The unburnt hydrocarbons in diesel exhaust can certainly cause cancer, although how much you'd have to breathe isn't listed. That's the real problem with these laws (and similar "avoid anything with any toxicity at all" clickbait) is that they ignore the dosage. Toxicity is meaningless without a dosage, and those labels are equally meaningless. Certainly you want to avoid bioaccumulation, but even then you have to wonder if the warning was for "millions of years of exposure might be dangerous" or worse. I have a similar attitude with hypergolics. Using them for a first stage is a cr
  5. This basically assumes that Falcon Heavy can lift considerably more to LEO than Falcon 9 expendable. Which in turn assumes that Block 5 was designed with that in mind and provided the support for ~150 ton loads to orbit (as the infallible wiki claims). I'm a big fan of Falcon Heavy, and have seen no evidence implying that at all. But the bigger problem for SLS is that any timescale for NASA planning for Mars would be far more than a decade away. So any plan to include SLS would have to provide for the thing to survive Shelby's 2022 retirement. And a commitment to keep the ISS going f
  6. In other news, NASA is paying BWXT ~$9.4M for one year's development of a nuclear thermal rocket. Granted, I'm sure they are using fission, but it seems more likely than some powerpoint slides will progress quickly towards fusion. https://arstechnica.com/science/2021/04/rocket-report-spacex-abandons-catching-fairings-ula-bets-on-upper-stages/
  7. In other news, SpaceX has given up on catching fairings in nets, showing that they realize that the wind is just to variable to control. Then there's the issue of "do you just release the parachutes and make them disposable", which might rub Elon the wrong way. When I first joined this forum I was convinced that parachutes were the way to go (something KSP teaches badly), but now I'm highly skeptical of combining parachutes with landing in exact locations (one or the other is fine).
  8. Nearly all the work directed at that involved looking for another planet inside Mercury. Einstein's motivation was to extend his Theory of Relativity (then only Special Relativity) to show that the laws of physics held in accelerated fields of reference, instead of just at arbitrary fixed velocity. Explaining Mercury precession just helped justify acceptance of a pretty extreme theory.
  9. I'd have to assume the whole scaling issue would be a bigger problem than the wind. The shuttle SRBs splashed down over 44 m/s (I remember reading >100mph), although it is possible that Starship will be lighter. If you are planning on falling through the upper atmosphere, I'd still think you could use drogue chutes to cut your delta-v. You'd still need retro-rockets, but far less fuel (and thus more mass going up, assuming the parachutes were lighter than the propellant mass. Which isn't a guaranteed thing).
  10. The real question is what happens when they don't sell him a nuke. What does he come up with? Is it safer for the US or Chinese just to sell him a nuke?
  11. A U2 managed to glide from Tennessee to Arizona (or vice versa. Call it 2500km if you aren't familiar with American geography). Of course you could claim that a U2 was a glider with a jet engine. Then there's the Pelan/Perlan 2. How does it soar? How about higher than said U2. U2 (I think the story involves a SR-71) to flight control: "request clearance for FL600" (60,000 ft, call it 18km) Air Traffic Control: "(joking) it is yours if you can get that high" U2: "descending to FL600" Probably mythical, as I don't think 60,000 ft is controlled airspace (modulo notice to a
  12. Well, the real ratio of Dawn ion thrust vs Em drive is infinite. On the other hand, a blue* LED will do exactly what the Em drive claimed to do: put energy in and get momentum out, without using any propellant outside of the energy you put in your device. Just don't expect to get within a factor of 30 of Dawn. If you wanted to scale Dawn up, consider accelerating the ions in something more like a cyclotron. Thanks to relativity, your "delta momentum" is just the force of thrust (F=dp/dt): this doesn't really change as you approach c. * blue chosen because I think the equations sca
  13. Most shots fired during war are to force the enemy to take cover in place, or at least be more careful while moving (and considering the number of bullets fired to the casualties, this has to be an understatement). My guess is that such indirect fire simply didn't have the psychological effect as direct fire as the troops wouldn't see/hear the shots and they didn't make enough noise when they landed for the soldiers to be aware they were being shot at. Not to mention that you would have to land in the trench to do any good. I'd be shocked if any side during WWI could even make enough
  14. "Unscheduled" presumably means just that. It wasn't on the flight plan, but happened when it veered off course and the range officer (human or software) pushed the big red button and the rapid disassembly happened. I suspect you also have to push it early enough that the debris falls in the allowed area. Sorry. All sufficiently large vehicles are anthropomorphized. Probably predates Homer.
  15. If you put the tank on top of the booster, made it smaller and a vacuum engine (J-2X), you'd have an Ares rocket (one prototype made in 2009).
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