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wumpus

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  1. Have to wonder if they are eating Stratolaunch's (intended, not provably real) lunch. They appear to have the worlds best "hypersonic testing facility" on the Earth. With the claimed recovery of all launch tests, this might make some customers wonder if adjusting a scramjet test to handle 10kG of lateral load might be worth it. Best guess is that they have to move as fast as possible to try to get the big yeeter up and running, and don't have time to talk about anything else. This might be the most progress on the craziest idea I've ever seen in spaceflight.
  2. Which is a bit odd, because the Shuttle was a political triumph for NASA. Between covering all the politicians pet projects and the sunk cost fallacy being what it is, they managed nearly 200 manned missions with the thing. On the downside, getting that political triumph required a set of requirements that lead the engineers to create what we now know as "the Shuttle", and even with hindsight several threads worth of attempts have yet to make a better Shuttle that fits all the requirements needed at design time (one of the big ones was dropped late, but they effectively had to cover it). You'd think they'd learn from the success. But more likely they didn't understand why Apollo was canceled. So not only magic Isp but magic engines. Because either those engines rotate or are duplicated and still don't overdo the mass issues of SSTO. And of course all those SF vehicles somehow don't abuse the landing pad (Kirk landed his Klingon Bird of Prey in a 20th century park, Stormtroopers stood nearby the Millennium Falcon when we first saw it take off) even with a TWR>>1. On the other hand, Arthur C. Clarke was right about the definition of "magic" and such things might well be possible well before the 2200s.
  3. Sounds a lot like a global extinction of specific species not related to a climate event. In other words, wouldn't happen naturally. A separate species hunting them all down across multiple star systems (like multiple continents) on Earth might be possible. See the extinction of small pox on Earth. Typically, if humans do manage to extinctify all members of a species on multiple continents, I suspect that only the last few were known historically, and some effort is involved for the last.
  4. Note that Draco is optimized for vacuum, Superdraco needs to operate in the atmosphere (and at low pressures as well), this may be a big reason in the difference in Isp. No idea about superdraco not being restartable: being hypergolic, most of the issues are moot. I'm guessing that it has turbopumps (couldn't find data), as it appears considerably more complicated than you would expect from a pressure fed engine. Certainly it is designed to be reusable, the only reason they'd only bring enough fuel to start the turbopumps once is that it only fires for aborts: no need to fire it again.
  5. And for an 8 year update (before it is wisely locked again), this format apparently *does* exist, but is only used for situations where the "billion year lifespan" might be useful. Not sure what the tech takes, but I'd guess that it involves using scanning electron microscopes for both reading and writing. It doesn't look like anybody has ever read written data except for verification and experiments. But the "arch-foundation" appears to like making these things as some sort of non-flamible library of Alexandria, or perhaps future Dead Sea scrolls. Don't expect to buy a writer from Amazon to back up your drive.
  6. Early on, there was an issue with the whole craft shaking as it transitioned from day to night (presumably every 45 minutes). Not sure if they ever sorted that out or just learned to live with it. I remember a "letter to the Washington Post" claiming that NASA should have dropped everything and made some adjustments based on offhand comments from their next-door northern neighbors (you can see the NSA from the Goddard assembly building) without any explanation (they were still "Never Say Anything").
  7. Interesting assumption. I'd assume that the K-Pg extinction asteroid might have been similar to Halley's comet, except that it would be rocky instead of an iceball. Although for all we know, Halley's might have an irridium core (we know from the tail that it is an iceball). So while we can predict when Halley's comet will return, can we predict its trajectory before we see it? It is trivial to send out a DART-like probe to bop its Pe beyond the inner planets, but by the time it starts passing Neptune it is too late. I'd assume that had the dinosaurs had at least 21st century tech for several thousand years they could have easily performed the "DART the K-Pg asteroid" out of the way if they knew it was coming, but does the Kuiper Belt redirect things? Sure it is *sparse*, but it barely takes any force at all at that distance to significantly alter the orbit near the Sun.
  8. And I get December 11, 2021. Not sure if it is fixed, or simply my browser is more willing to interpret dates (see Excel for extreme cases).
  9. I think the bigger question is how they expect to get this thing in better condition than it is now. The SRBs were stacked relatively early and the "shelf life" is ticking. They already have issues with leaks and are going to roll this thing back and forth again. If they want to launch it, somebody is going to have to decide to light the candle, probably with less than perfect confidence of success.
  10. Today I learned that Gargamel bicycles a lot... Or possibly motorcycles. Or even challenges records at the Salt Flats. But I think its bicyclists are most likely to take aeronautic drag personally.
  11. As far as I know, the system is called "Phalanx". Supposedly the term means the whole system from the RADAR to weapons control, but the media typically just refers to the gun itself as "Phalanx". This sounds like what I was working on in the 1990s, where they were trying to tie all the communications of the ship together, some long alphanumeric string lost to time like AN/Q80, which tied together a bunch of systems including "Phalanx". All our company did was build trainer RADAR consoles, computer-monitor map tables (no idea if anyone set up the projection system to show any big football games), and submarine monitor relays (a monitor that let you choose from various video inputs). The whole notion of "Commander's" probably doesn't make any sense to the Navy. Presumably everything is fed to the captain anyway. Having the weapons system controlled by anyone not onboard ship doesn't sound like something they'd be happy about, although I suspect they beam E2C/D/F RADAR information from the "eyes in the sky" to various surface ships.
  12. Old models are being shown to be obsolete by Webb data. Fortunately Webb is providing much more accurate data to construct new models. Why do I get the idea that the old models are only as accurate as they are thanks to Hubble data?
  13. Both the SLS and Saturn V use hydrogen as a major component of fuel (everything but the boosters for SLS, everything past stage 1 for Saturn V), so I'd expect that a more modern methane-based rocket might not scale the same as a Saturn V. Also if you are building an extra large rocket, making it wider starts making a lot more sense making the thing taller. Rockets are made tall both for aerodynamic reasons, and logistical. The falcon 9 is sized to be put on a truck and moved via US roads. I remember an aside from Scott Manley stating that the Falcon 9 (block 5) was roughly at the limit of length for a rocket that fits the Falcon 9 width requirements. And don't forget that they didn't build straight to the limit. They incrementally increased the size of the thing and only after 4 more upgrades got to the limit. If you are dealing with the square-cube issue for thrust, don't forget SRBs. They deal out nearly arbitrary amounts of thrust even if they are much more expensive than what Jeb taught you in KSP (but the ISP isn't nearly as bad). Check out the AJ260 for a really big SRB.
  14. Anyone know how this effects the proverbial "hydrogen car"? I'm guessing that the "gas pump tank" would be more or less at ground temperature, and the hydrogen would rapidly drop in pressure/temperature down the pipe as it encountered a relatively empty tank. Temperature fluxuations would also be a thing, but certainly not hundreds of kelvin.
  15. I googled expecting to see an IBM hard drive model 3030, but instead it was the 3340. The "30-30" came from 30MB (fixed stack) and a stack of 30 MB removable storage. No idea how much each disc held, but wouldn't be surprised if it was ~1MB. Thus named after the famous .30-30 Winchester rifle.
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