Jump to content


  • Content Count

  • Joined

  • Last visited

Community Reputation

1,146 Excellent


About wumpus

  • Rank
    Spacecraft Engineer

Recent Profile Visitors

The recent visitors block is disabled and is not being shown to other users.

  1. Not true. Nuclear energy has wide use in thermoelectric generators that simply use the energy that radioactive materials actively radiate. These are more or less mandatory on any probe going past Mars. There have also been a few devices (https://en.wikipedia.org/wiki/BES-5) that appear to be the same idea, but "kicked up" a little with an additional neutron supply. More likely the biggest difficulty with putting a reactor approaching criticality would be getting the budget for such a massive undertaking (not so much the reactor as whatever *needed* that much power put in space), although I
  2. I'd have to wonder if this would lead to the use of parachutes. Not so much to rescue the passengers during a disaster (although it might be sold as such), but to act similar to the parachutes used by drag racers to extend the runway and hopefully use a smaller airport.
  3. I'm pretty sure the Vogon planet destroyer (which destroyed Earth to make way for an intersteller bypass and famously hovered "like bricks don't") hovered at a similar altitude or lower. Visibility was key. And almost on a level with the Vogons. The important bits are visual (or audio for HHGTG), which far outweigh the science in the director's eyes.
  4. I'd have to assume mass would be a big reason.
  5. What would you want the power for anyway? The challenge is harnessing the energy of the Orion without melting the spacecraft. The amount of energy is the problem, not the fact that you waste nearly all of it. The point was figuring out a way to *use* that enormous [low mass] energy in *some* way. Also the only real reason you would want this is for "Fallout" [US 1950's "gas-punk" retro future] styling. Of course, you'd have to make it a V-8. Don't forget that every Watt of power that isn't being used as a spring (Orion needs dampers, doesn't it? Those produce nearly all the h
  6. Those laws are written by more or less the same crew that keep shoveling money into SLS (well, the Senate is the main source, thus Senate Launch System, but it can't keep going without the House along for the ride).
  7. Intercepting an orbit ("first one") means not only being in the same spot, but having the same orbit (otherwise you'd be moving at different velocities). A fast ISS intercept has the advantage in that you are actually waiting arbitrarily long for the ISS to be in the right position for you launch pad before you "start the clock" at liftoff. Fastest possible intercept is flying toward the ISS at full speed (whatever that is, obviously less than c), followed by a "suicide burn" that corrects your orbital velocity and hopefully doesn't spray the ISS or ISS orbital path with exhaust particl
  8. I've heard that crossbows were used to a limited extent in the Korean War (but probably not since). Back when I was a boy scout, I learned that crossbows were more regulated than rifles in my home state. Most of this was likely that they could easily restrict crossbows (and modern ones look scary), but also that they are silent, penetrate soft body armor, and have no muzzle flash (but do point back to their shooter when they stick in something). https://www.youtube.com/watch?v=NTJnyQ-bZLU The ancient weapons segment of youtube went crazy over this set of videos. A mad German engin
  9. Analog computers work on integrals (which reduce noise) and avoid derivatives (which amplify noise). With less complicated equations you just integrate them until the derivatives go away, but I'm not sure about yours. To be honest, the only time I've ever heard about analog electrical computers was as a pre-req for DSP type courses (it introduced the fourier transform and used analog computers as an example of the systems you needed to emulate). To even have a prayer of getting the analog computer in the same class of a digital one (even a cheap desktop CPU), you'd almost certainly have to
  10. Sounds like what happens to marathon runners after mile 20 or so. The human body can only store so much glucose, so after about 20 miles or so you run out and it starts to tear apart the rest of the body for more energy (although even the most serious runner has enough fat to last >>100 miles.
  11. I'm pretty sure there are a few more issues, like cost of catalysts and the efficiency of cracking methane (water is only cracked for PR purposes). But you're right in that there would likely be enough work done to make it happen if the really tough issue (hydrogen transportation and storage) went away.
  12. And according to Musk, to validate the design of the factory as much if not more than the design of the rocket. After having issues scaling up Tesla model 3, he's trying to be more like Henry Ford (as interested in the factory design as the car itself. He might even have to increase the "crank level" a bit to match Ford).
  13. I'm not aware of any government customer not interested in micromangement, not dumping a ton of "government contractor regulations" on contractors (required even for <10 person startups. Been there, done that.), and not interested in maximizing pork. That isn't how they operate. As far as I know, the US government even buys *gasoline* this way, or at least one major contract in Iraq worked that way. It has nothing to do with space and everything to do with how the agency is funded. That was NASA's strategy in the 20th century. Two Voyagers, pretty much at least two of everythin
  14. Spacex was something like 2 days from bankruptcy without state funding. They had a perfectly good orbital rocket (Falcon 1) and not enough customers to stay in business. Orbital needed a B-52 (not sure if surplus, leased, or borrowed from the Air Force) and almost certainly relied on government customers. The idea of a non-government funded private space actually succeeding might be limited to Rocket Labs (and I suspect that there's enough government contracts to make or break them). Perhaps Bezos-funded Blue Origin will launch things into orbit, but it looks like they're sticking to build
  • Create New...