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wumpus

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  1. Boeing aircraft division will certainly sell the government any of the models of jets it already produces. They might even be willing to have a fixed price contract for minor alterations for specific military use. The catch is that unless the US Govt wants to buy additional Atlas and/or Delta rockets (and not from ULA), anything Boeing does for NASA is going to involve a ton of NRE (non recurring engineering) - And yes. I've been on projects with fixed prices and the (DoD) customer insists on customizing the product during design. There's a reason that those fixed budgets are about 10 times what it would cost to make a product for commercial sales. But it doesn't look like even that is good enough for Boeing (space).
  2. I'm shocked that any would bother. Perhaps it was more useful than I thought. The other question is if anybody progressed past a reading level of a "first year after learning to read" that a modern child would have. With no books and little else to practice with, they couldn't have been any good at reading or writing. I'd be impressed if 1% could read what somebody else "literate in only the vulgar" could write. Once upon a time there was KerbalEdu, a KSP edition for education. As far as I know, this is the only edition of KSP with included DRM. The wiki link has a webpage for it, but I'm not getting any response. It's dead, Jim. I think it died before the release of KSP 1.0, and certainly wouldn't have survived the K2 buyout. I don't think it was ever all that successful, and probably had too much trouble trying to retrofit all the Edu mods to work with the then-evolving KSP code tree. https://wiki.kerbalspaceprogram.com/wiki/KerbalEdu
  3. Another point is that post Apollo funding for NASA withered and died. Skylab was launched (and crewed) with Apollo hardware, and after that they sat around and designed a millstone to tie themselves to called "STS/Shuttle" (this lead to great political success with Congress easily budgeting for sunk costs, but often seen as a technical loss). If Soviet rocketry had spent the money needed, how long could they maintain it? And when the Kremlin/military was no longer interested, would they still be capable of creating all those space stations, crewing said space stations, and developing the Energia engines? I think this also ignores all the things that could have gone wrong for NASA: mostly involving the death of the crew (especially after burning the crew of Apollo 1 to death) of Apollo 11 and subsequent unwillingness to continue trying. NASA seemed to be blessed with sufficient contingency plans to allow major failures of any one project to be sidelined and replaced with another project (my favorite: the AJ260 boosters that were more powerful than the shuttle SRBs. If they couldn't make the biggest stable combustion chamber ever for the F1s, the AJ260 could do even more). I will admit that I'm blanking for many more ways for NASA to fail: it would probably require political games such as keeping von Braum out of the system (like with Vanguard). The great thing about the Apollo project (including Gemini) was that it was effectively an entire new bureaucracy, built from the ground up to do one thing, and said thing had a sufficiently hard deadline to allow them to ignore meddling politicians. There are plenty of ways for Artemis to fail that really wouldn't have applied to Apollo, and even Artemis was designed first and foremost to be resistant to being canceled by Congress (all technical decisions were secondary).
  4. I suspect that the easiest way to test this is to find large mushrooms in the forest and weigh one down with increasing weight until it crushes, and then pluck another and weigh the stem. It should be relatively easy to find the amount of mass a mushroom stem can support. If you really want trees, you are going to have to assume some sort fungus that evolves a hard cellulose internal structure without crossing over into being a tree (presumably lack of photosynthesis would be the obvious issue). Best guess of the shape for a giant mushroom with an elevation to disperse spores would be a cone/pyramidal shape (use above experiment to calculate the angle/shape) with most of the mass spread out near the ground/underground. Of course then you have to figure out where the energy source comes from if it can't photosynthesize and blocks anything below it from photosynthesizing as well. Perhaps something along a river, draining nutritious silt?
  5. That was a huge unforced error, although I'm not sure where you can find undeveloped land on any US coastal area that isn't a wildlife refuge. There are better ways of determining just how strong your launchpad needs to be, especially after building in a wildlife refuge. Did they hire Calvin's dad* as the engineer? I still think that the booster still intact until 40 seconds after the automated "Big Red Button" was pushed is going to make the FAA even more cranky than the former. Granted, I'm not in the industry at all, but 40 seconds of uncontrolled travel of a huge tube of liquid oxygen + fuel sounds bad. * Calvin's dad is famous for bad answers to science questions. For this example he suggested that to find the maximum load of a bridge you should build it first, test it to destruction, then rebuild it with the known "max load" clearly labeled.
  6. One of my favorite games (largely thanks to working on outdated equipment I had lying around). http://www.deltatao.com/ho/ A 4X game pruned to the very limit. Just start with a planet with the understanding that "this here galaxy only has room for one player's people". Alas it has been removed from Google play, limiting my access to it.
  7. This seems to be one of those things that KSP <1.0 taught that wasn't quite right. Of course it also taught (and still teaches) that a RL-10 engine is cheap. Aerodyne says otherwise. But you need a lot less thrust on a second stage than you'd put in a sustainer, and that weight comes out of your cargo capacity (much worse than forcing the first stage to lift the dead weight of the second stage engine). I think the most important consideration is just how confident you are that the second stage will light. If you can get it to light, then you want a two stage rocket. If you aren't so confident, then a sustainer is ideal. Another thing to unlearn from KSP. And it looks like the highest Chinese launch site gets .8 bar at launch. Helps a little, but might not be worth redesigning a nozzle. You'd be surprised how thin air can be and still be able to breathe (a lot higher than that).
  8. I think the real issue is how you construct the habitat modules. As far as I know, all such modules have been constructed on Earth, and connected together through some sort of docking (likely permanently) seal. If you stick to this, rotating around the center of the spacecraft would be limited by the radius that can be launched. An alternative would be two (or more) habitats placed outside the center of the main rotation, and rotated. Presumably you'd need a ladder to get back to the zero-g center and on to a different gravity habitat, at least until you could build a ring around the center. Expect to have a two "wasted modules" for each connection to from 0-g to 1-g.
  9. The gotcha is that 3 launcher platforms that solved altitude compensation all failed. Pegasus (+XL) is basically retired Stratolaunch isn't interested in orbital launches Virgin Galactic (the air-launch to orbit company) is bankrupt and nobody is interested in the rocket Not to mention, using a 2 stage rocket gives you ideal vacuum Isp for most of the delta-v needed. Didn't somebody slap a moveable extension onto a sustainer already, or was the proposal tabled before construction/launch? I think China has a launch facility at altitude, but no idea how that will affect nozzles and pressure design.
  10. Do they play "the Immigrant Song"? Any chance to run to shore, loot a monastery, and run back? Dragon-prowed ships aren't exclusively Chinese. Please ignore boat/ship issues.
  11. "Space is big. You just won't believe how vastly, hugely, mind-bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space." Douglas Adams You really can't fill up space. You'd have a hard enough time filling up the elliptic. You can have issues with space junk in Earth orbit, and certainly any debris crossing GSO would be bad. But those are just tiny portions of space that humans care about. In general, any debris field will rotate and expand around the Sun until it might not exist. Compare to the asteroid belt. As far as I know, no craft has ever needed to take evasive action in the asteroid belt and that is almost certainly the canonical example of "space debris field". Also look at the "space metro map": the map only cares about delta-v, because you are unlikely to ever use the same route twice between the planets. There really is nowhere for "space pirates" to lay in wait, with the possible exception of a weird orbit that will just happen to line up with an optimal launch window between planets the next orbit or two (and even then, it is a one-shot event. You'll have to move on to be in position for the next good launch window. And if there *are* space pirates, you probably aren't going to wait until the window opens up, especially if it increases the chances of a lost vessel. To answer the original question (why, why do I do this?), it depends. If avoiding RADAR detection is key, then they will look like current atmospheric missiles. If not, expect spherical tanks, possibly with multiple stages of large/medium/small tanks (hint: think of the rocket equation). I've assumed some sort of stealth, but thinking about it a bit more it should be trivial to cover any likely battlefield (like the solar system) with enough sensors to watch for missiles firing their engines.
  12. I have to wonder if the North American common frog is even the same genus let alone species as the European (or at least English) common frog (or at least "frog commonly near populated areas"). Unless invasive species are at work (easy enough for a frog to hitch a ride), then I wouldn't expect them to sound the same. Similar for Africa (don't think there are liniked frog habitats between Africa and Eurasia) South America, and Australia.
  13. They also knew they only had one shot for the "full tour" for at least a hundred years. So there was even more desire to overbuild. But if they wanted to extend the mission, they could have used americanium instead of plutonium in the RTGs. But that would have reduced margins and/or added mass during the critical moments when near planets. So plutonium was ideal and they went with that (and they were also familiar with plutonium RTGs).
  14. At $100k a head (more likely 3-4 times that in overhead), that's a billion dollars a year. Doesn't Bezos cover at least a billion/yr in burn rate, and hopefully they are getting some money for the vulcans (but the billions a year presumably necessary?). All that money has to go somewhere. I'm guessing at 10k employees, the average salary has to get pushed down a bit.
  15. Do you have 24 players on each side as well? Could you even see the puck as you kick it around (no room to swing a stick).
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