wumpus

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About wumpus

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  1. Good luck showing that life emerged on Venus: it isn't a place I'd expect to find any fossils. Similarly, I'm not aware of any era in time that fossilization was possible that doesn't contain evidence of life. Earth life could have easily been seeded by Venus (or any other planet), especially if both planets were under asteroid bombardment (I'm unclear about when this happened vs. when life appeared, but it really only requires one meteror with the exact right exit velocity of debris). Panspermia across solar systems would be different from panspermia across planets. Unless you want to posit that the missing dark matter is extra globs of life being flung through the universe where we assume there is only hydrogen gas. I can't imagine how much mass it would take to typically seed a galaxy with life (especially if it has to get to a solar system with the first few hundred million years).
  2. Issac Asimov was able to give robots unexpected emergent behavior with only three laws. I wonder if future robot/AI software will have similar issues with traditional, layer-based software development. Especially if multiple middleware vendors each include routines to further their own interests.
  3. Since Blue Origin appears only to be getting relatively small contracts from NASA and slightly larger subcontracting jobs from others (which means the prime helps themselves to 25%+ of whatever Blue Origin would get), I'm guessing they need around that much money. It is mainly what keeps Blue Origin in discussions on a level with ULA, Spacex, and Roscosmos, even if they've so far only done unmanned suborbital launches. This cartoon is wrong: planes don't fly thanks to aerodynamics. Planes fly on money (something that was in a coworker's pilot and/or A&R mechanic training). Rockets fly thanks to much more money. There's also no indication that lack of money is a problem at Blue Origin, or that adding even more money would help. It may be their slow progress is intentional, either to learn from the mistakes of others, or merely guessing that others are moving to fast and will hit big problems. Spacex (and Tesla) seem to consume Elon Musk's entire life. Blue Origin appears to be a hobby that Bezos pays CEO Bob Smith to run. Bezos is probably limited by how much attention he can give to Blue Origin, especially with Microsoft trying to eat Amazon's AWS lunch. Lack of money seemed to be what killed Armadillo Aerospace: as rich as John Carmac may seem, he couldn't afford to run a space company as a hobby.
  4. Not from this evidence. You'd need to know the likelyhood of life being randomly produced from organic molecules. You'd have to intentionally select the exact extremephiles you wanted to contaminate Venus with and splash them all over the parachutes. While plenty of the conditions that probe was built/transported/launched might be considered extreme, I'd expect any of the "right" microbe would simply be eaten by ordinary microbes evolved to Russian conditions. This really calls for a "Wolftrap". Put a glider in Venus' atmosphere and load it with various organic chemicals including phosphorus and see if any phosphine is produced.
  5. The shuttle had a 1:1 glide ratio. How much lower do you plan on going? How fast do you have to land?
  6. Dawn used 25kW per Newton, and holds the record for the most delta-V of any spacecraft ~10km/s. It is quite possible that a deepspace probe would burn through a first stage of Argon, then a much smaller second stage of Xenon, and finally use photons until the nuclear power ran out. To be honest, when using photonic drives, make sure your heatsinks are design with the black sides facing in the direction you want to thrust. They will be a significant part of your thrust (i.e. you aren't going to have much at all).
  7. The problem with HL is that those wings are heavy. The Shuttle had 3 kg of orbiter mass for every 1kg of cargo. While I don't think the Starship/payload ratio is a key driver is Starship design, I still think they will do significantly better. HL does have a huge safety advantage (which is odd, because the shuttle had the glide ratio of a brick), so we still might see it again. Poul Anderson published "Orion shall Rise" two years earlier. It was a post-apocalyptic work, so his Orion was more as minimalist as possible and still reach anywhere in the Solar System. Slapping shuttles on Orion makes a good image, but has anybody figured out what it takes to get a RS-25 to restart, or was it a strictly one-way flight (the Footfall Orion was a warship during an alien invasion of Earth).
  8. SSTOs based on hydrolox while physically possible have a lousy mass fraction and a huge problem getting enough thrust out of the hydrolox engines. Reusable SSTOs would have to use something other than hydrolox (air breathers, ground-based power, who knows) because the mass fraction of a chemical based rocket simply doesn't have enough mass for the hardware needed to survive de-orbiting and landing. Sure, it is better than a device that ignores the conservation of momentum, but that doesn't mean you can build a snowball that can survive being tossed in the Sun or a reusable SSTO that relies on hydrolox. I'm mostly irked that X-43 lost further funding. That at least got off paper and up to mach 9.6. Granted, that tech won't be particularly useful for decades (it will be a long time before fuel consumption has an effect on the cost of a rocket), but getting an air-breather to take you above even to 2000m/s would significantly change the floor of the cost to get things into orbit. So include the X-43D and beyond on this list (I think the X-43A through X-43C were all launched). I also like "beamed power" for SSTOs, but that really belongs on powerpoint for even longer than hypersonic airbreathers. Of course it is quite possible that military lasers might be beaten into ploughshears (presumably after becoming an open secret) to make this happen (who else would develop the lasers/masers? Starship isn't going to be an SSTO. There will be Starship (that goes to orbit), and the Super Heavy Booster that gets them the first 3km/s-9km/s of the way there. Granted, *both* will look like the Delta Clipper, and I suspect even moreso when combined on the pad, but by not being SSTO the difficulty is quite plausible (there are few doubts that the booster will require significant technological development other than the already designed raptor engines and Falcon 9's proven landing capabilities). Getting Starship to survive orbital descent and having humans on board a vertical landing** are one of the reasons they are building so many prototypes. And no, neither one will be a reusable SSTO on its own. Starship will only have the sea-level thrust to land when empty*. Super Heavy Booster won't be able to survive de-orbiting (even it if can SSTO on its own). If de-orbiting was that easy, I'd have expected Starship to have orbited already. * main engines are for vacuum. Although I might be wrong if they use them as a launch abort system. I'd still expect it to get out of there and simply burn up the fuel before an aborted landing ** I'm pretty sure even Elon knows that NASA won't let him to this until 2030 at least.
  9. American schoolchildren are taught that Abraham Lincoln did his homework on slate tablets (no idea of the truth), so presumably they were in use in the western USA around 1800 or so. Probably a lot easier digging up rock locally than shipping from the East. Film/tape is used interchangeably to record video with tape for audio. And those terms don't appear to be changing, "to NAND flash" just doesn't specify what you are saving nor does "to SDHC" roll off the tongue any better (and the memory format is unlikely to last as long as film/tape did).
  10. There's a shocking amount of funding that NASA gives to SSTOs (anything non-zero should be shocking, but this was a pretty significant project). One thing to note: like "NASA doesn't build rockets, contractors do". NASA doesn't hire employees (there are exceptions), they hire contractors. I also have wonder just who NASA employees are, and what their backgrounds are. I'd have to assume that anybody connected to the Apollo hiring wave has long since retired (and probably dead). I'd guess that anybody around when they were designing/building the first shuttles is retired/retiring. It won't be too long until they run out of employees who joined up with NASA and are down to pure apparachniks (the contractors do all the real work). My guess is that this is why SSTO projects still get funding. Rumor has it that DC-X was cheap to launch, but that might just have been thanks to size. I've often said that once Space-x gets rocket building costs under control (they've done an amazing job at that), that cutting launch costs will be the next big thing and that Blue Origin (which started out with a lot of DC-X alumni) would have a leg up.
  11. A smart phone connected to google (presumably really just the starships' servers, but in Star Trek they *could* access datacenters half a galaxy away). The whole point is to get the plot going as fast as possible and to deliver said information quickly to the crew and audience. See also "as you know, Bob".
  12. Anchoring bias. The first time people hear about it is the excited "breakthrough" reported from the researcher's PR agency. Anything failure to reproduce the effect is dismissed as "git gud". Not to mention that anyone seriously pushing any such nonsense has a significant chance of absolutely refusing to admit their (ok, typically "he's") wrong. My guess is metallic hydrogen will be in KSP if it fills a needed place in the tech tree and won't be included if not. There's always the chance than one of the devs really likes the idea of metallic hydrogen (hopefully knowing full well it won't work that way) and we're stuck with it. We can always push for the term "zip fuel" (what they called the hypothetical high-Isp fuel in Ignition!), but I suspect the devs would prefer a more well known (and googleable) term. If you want realism in KSP, you need RSS/RO. Otherwise you have to live with little green men.
  13. I remember hearing one story that the Soviets (presumably Stalin personally) made a conscious decision to *not* upgrade tanks during the Great Patriotic War. Maybe it was just the T-34. But the overall point was that while it certainly made the tanks more vulnerable, it also made the logistics issues in churning out tanks and spare parts far easier. Did they bother with spare parts? Or did they just send mechanics to strip as many parts of destroyed tanks and send them back to the factories? My impression of the thing was that it was the perfect tank for the Eastern Front. MTBF rated in days, but considering the life expectancy of any tank in a WWII battle (much less the Eastern Front) was measured in hours once they got to the front (let alone the enemy). Tank fans love to ooh and ahh over German designs. The thing is that Germans could spend their time making the "perfect tank" because they only had enough diesel fuel for a relatively small amount of tanks. The USSR (and USA) could pretty much fuel every tank they could make (as long as they held Stalingrad and the oil fields), so slapping out as many (if not to German quality levels) tanks as possible made sense. "No improvements" may have played an important role in Soviet tank production. Maybe you could have a fancy new IS-3, or perhaps 10 or so T-34s (with spares). The choice (in the unlikely event that they gave field commanders choices) would presumably depend on the German anti-tank availability (and of course if they still had diesel for their tanks). This whole meandering post is that logistics win wars, and that ECOing something fielded is an unholy nightmare. But I will also agree that once weapons and moreso defenses get obsoleted in warfare, it is fast and permanent. At that point you will need some better, and you will need it now. But if you already have three marks of "like to have it" ECOs in the field of varying levels of upgrades, that very well could get in the way of bringing the right equipment to the warfighter.
  14. The milky way is spinning, and presumably the Sun with it. Beyond that, I don't think there's a clear definition of 'interstellar medium'. About the only thing clear is that the effects of the universe's expansion are much larger than any velocity the Sun might have (by measuring redshifts of other suns/galaxys).
  15. The US had plenty of unemployment during and before the Great Depression, and almost no regulation. I'm curious what other unregulated (and especially unsubsidized) economies went without unemployment for long. Recessions were nasty before the New Deal. Rest of this post pre-scrubbed.