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About cpast

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    Rocket Scientist
  1. Live On Board Of Submarine

    My understanding of spacecraft is that bunks are more for privacy than comfort; from what I've read from astronauts, the only reason they need sleeping bags is so they don't bump into stuff (and the ISS does have enough quarters for everyone to have private quarters). Capsules are a different story, I'd imagine.
  2. Team SpaceX or team NASA?

    My initial point that started this whole thing was that the US government already does its rocketry pretty much by giving the private sector money and having them come up with the hardware. AngelLestat was saying that the private sector seemed to be better at doing this stuff cheaply than the government is, so the government should give its budget to the private sector and have them do it; I was saying that this is basically what happens. In a broader context, yeah, Atlas and Thor were run by the USAF. I wasn't trying to say otherwise; I was just saying that the US government did the development by giving private companies money and having them do the technical details. I think we're in violent agreement about how the projects were actually done, and are just using different terms.
  3. There aren't that many of those, and they do need other stuff (like a sense that they probably aren't going to die). The people who have many millions of dollars are generally not the people who are willing to take a decent risk of death in such a mission. The intersection of people with the technical ability to troubleshoot issues, the physical and mental attributes required to go on a Mars mission (particularly an early one), the willingness to brave the risk that something will go wrong and you *cannot* be rescued by anyone, the willingness and ability to spend at least a year without personal contact with anyone back home, and the money to pay for such a mission is not very large. And people who go on trips like that *don't* generally go alone -- they have guides, who are competent professionals. Space tourists these days go as one person on a capsule with at least 2 competent and qualified astronauts who can deal with issues. So you need to reduce the paying passengers on your Mars mission to account for the people who know what they're doing. As for pricing: Millionaires wouldn't be able to afford a seat. It costs over $50M for a single seat on a Soyuz to the ISS. That's per one seat, to LEO, as part of a well-tested system that has paid off its development costs. It would be reasonable to assume a Mars seat would cost at least an order of magnitude more, significantly reducing the number of people who could pay for it. Space tourism really isn't likely to be an avenue for initial missions somewhere. The issue with that is that you need to take a lot of infrastructure along to do those activities, and (for legality) unless the people in charge go along also, they aren't exactly immune from laws on Earth. Safety is a different matter; leaving aside ethics of contaminating Mars, it is a pretty good quarantine, so things might well be better there than on Earth if they're risky. True, but why's that need to be a manned mission?
  4. Team SpaceX or team NASA?

    Nope. Atlas was developed by Convair (then General Dynamics, then Lockheed) under contract. It was neither designed nor built by US government employees. Its chief designer, Karel Bossart, was a Convair employee. Thor had more USAF involvement, but the components were still all contracted out, and overall airframe and integration was done by Douglas, not by the Air Force. The fact that "USAF" was painted on the missiles means the USAF *bought* them, not that they *built* them. Seriously. Particularly for Atlas, the only sense in which it was a USAF project is that it was developed under a USAF contract. Which was my initial point -- the government does give money to private companies to do stuff like building rockets, and doesn't do it itself. Shuttle SRBs. Successful (if uneconomical) landing of a first stage for reuse. I said they haven't *done* anything. Mission statements are nice and all, but they don't count as doing anything. Talk is cheap.
  5. Team SpaceX or team NASA?

    If you think the JWST is "just a few mirrors," there is no helping you. It's incredibly precise, as are all scientific telescopes. It's also sensors, power, monitoring, communications, reliability (you can't repair it, you can easily do repairs to a tower). Frankly, I think you have no clue what's involved in a scientific project. There weren't that many engineers on the Burj Khalifa. That's because almost no aspects of it are new in any way; after the design is down, it's just construction. And the engineers that were there command a much lower salary than those in aerospace, because there's plenty of supply. By and large, construction work is something people know how to do; in contrast, just about everyone involved with JWST is someone who commands a fairly high salary. Name one thing that NASA tried and failed to do and SpaceX succeeded at, which is *not* "do X for cheap" (NASA contracts stuff out once it gets to the "we know how to do this and want to do it cheap" point). SpaceX doesn't compete with NASA; they do not do the same thing at all. NASA is a scientific research agency focusing on aeronautics and space; they also have a mandate to help advance knowledge about aeronautics and spaceflight. SpaceX is the beneficiary of NASA research projects to learn fundamental concepts in spaceflight. SpaceX, on the other hand, does not launch their own missions. They aren't a mission generator. All they do is take money and launch payloads to LEO, which is something that NASA does not do (because they contract that out). SpaceX in fact gets a huge fraction (I think it's the majority, but am not sure) of its money from US federal contracts. As for cost: Since SpaceX does not compete with NASA, there is no valid cost comparison between the two. Instead, you compare them with the people who do things similar to them; in the US, that's companies like ULA. Anecdotally, SpaceX runs itself like a startup -- long hours, short terms employed there, low-ish salaries, but with the advantage of employees who believe in their work (it's not just a normal job). They also have low bureaucracy. Their competitors like Boeing and Lockheed run themselves like big companies, which often provides better working environments but costs more money (as companies grow, running them as a startup starts to work less and less well). SpaceX also has low overhead, partly because of size, partly because they do everything in-house. Incidentally, part of the reason I simply don't buy SpaceX as running a Mars mission at all is that SpaceX has done absolutely nothing to make me think they're interested in that sort of thing. They're a commercial launch provider. They put payloads in LEO. They do not launch things on their own dime unless it's a test that they can't get a payload for (if you notice, they try to combine tests with real missions whenever possible to save money). NASA, on the other hand, has an actual budget to fund missions without regard to how much profit it will make them. If SpaceX flies a manned mission to Mars, it'll be after coming up with someone to pay for it; the most likely bet is honestly NASA, which would make this a NASA mission at least as much as a SpaceX one (since NASA paid for it).
  6. Team SpaceX or team NASA?

    Nope. Atlas was a General Dynamics development before it was sold to Lockheed. Delta came from Thor, which had multiple contractors (Douglas did airframe and integration, Rocketdyne did engines, other companies did other aspects); although the USAF did take a bigger role there, by the time NASA was involved it (turning it into a pure space launch vehicle) it was a Douglas, then McDonnell Douglas, then Boeing project.
  7. Team SpaceX or team NASA?

    There's a lot you can do cheaply if you're paying your workers five dollars a day. JWST workers are largely highly skilled scientists and engineers who command fairly high salaries compared to most people in the US; Burj Khalifa *skilled* workers (skilled meaning "carpenters," not "engineers") still made less than $7/day. A tall building is not a precision structure; a huge amount of the work is driven by the costs of mass unskilled labor, and if you're paying a worker dollars per day, you're paying multiple orders of magnitude less than the work on JWST. The Burj Khalifa had much less need to consult with the top engineers and scientists who command high salaries wherever they go; most of the work was unskilled work done for less a day than a US fast-food worker makes in an hour. In your focus on size, you are seriously underestimating the cost of labor: that is by far the highest cost of any technically advanced project. That's how NASA already works. Much of their money goes to pay contractors. Contractors designed and built Apollo and the Shuttle. Atlas and Delta are built by contractors. Much of the work on Curiosity and JWST is contractor work. It's not clear contractors are ultimately cheaper than in-house. Incidentally: SpaceX gets most of its funding from the US government.
  8. [Philosophy] Red

    Look up "qualia;" that's the name for this concept of "experience as it's experienced by a mind."
  9. "Welfare" refers to domestic programs. I'm unclear how that can be "to counter the weapons sold to the zones of conflict." As for a source, here is a think-tank source on a US budget breakdown for FY2014. 24% on Social Security, 24% on four major national health-insurance programs, 18% on *all* defense spending, 11% for more social safety net programs, 7% for interest on the debt, and the rest to all other federal spending. High numbers for defense spending are the result of someone ignoring 60% of federal spending for procedural reasons. Essentially, most welfare programs are run as entitlement programs, in which the government must send X amount of money to people who show Y reason that they deserve it. These programs don't need to have Congress pass a law every year giving them money; such programs (there are other kinds as well) are called mandatory spending, because the money is spent unless Congress intervenes to change things. Discretionary spending is the opposite; Congress needs to explicitly pass an appropriations act every year to spend money on discretionary things. Here's the thing: Defense spending is virtually all discretionary, while welfare spending is largely mandatory. So, by ignoring money that must be spend and only counting money Congress explicitly voted to spend this year, you get defense as a huge part of federal spending. If you consider *all* federal spending, you get defense as less than a fifth of *federal* spending; it's even less if you consider that the feds spend just a bit over half of US government spending, and states spend almost nothing on defense (they do, however, spend *lots* on education, as do local governments). Basically: Before you believe something you read about US government spending, look at exactly what it's saying. If it's talking about percent of discretionary spending, that means that it's excluding the spending that the US government will do if Congress doesn't pass anything about anything (which is largely welfare). If it's talking about federal spending in general, know that the US federal government specializes in different things than state governments and local governments; for instance, education, which gets *lots* of money but very little of it at the federal level (similarly, defense gets very little money at the state level).
  10. When should I buy KSP?

    Also, there is absolutely no difference between Steam and Store versions. There is no DRM of any sort on either version; if you buy it off Steam, you have to download it off there and get updates from there, but there's no requirement to use Steam to play it (you can even move it out of the Steam folder into a different place and uninstall Steam, reinstalling for the next update).
  11. Flight Simulators

    An FAA-approved flight sim is a complete replica of a cockpit of a specific single type of aircraft; a class C or D sim lets you get a type rating to operate a specific sort of aircraft without ever having set foot in the real plane. To do that, it's not enough to have a single panel with a few switches; you want the exact control layout replicated, and everything doing the same thing it does on the real plane. Given that the sim has to have the hardware to exactly replicate the real control locations and switch types and similar, it's really not much (if any) of a savings using an Oculus, because what you basically save on are the big screens outside the cockpit windows (and that's not all that expensive to make, since it's not like it needs ultra-HD outside views). Where you might get savings is replacing the full-cockpit motion system with a seat-based motion system, but you don't need an Oculus for that.
  12. [Law] Upper end of airspace?

    Yes. And you kinda do need to read a post before commenting on it. The treaty contains no technicalities about what "in orbit" means, which was what the post of yours I quoted was about. To quote you: To quote me: The OST does not define "in orbit." That means it's not covering the technicalities of "in orbit." It's in a very real sense *irrelevant* what "in orbit" means, because any launch other than in orbit is going to provoke a nuclear response -- no one's going to be playing the technicalities of it. Anything that comes down will provoke a response; anything that doesn't is clearly in orbit. No one cares what the technical cutoff of "in orbit" is, because there is a powerful disincentive to launch suborbitally.
  13. [Law] Upper end of airspace?

    Actually, no. They didn't put it in the treaty. Please read my post: They simply said "no nuclear weapons in orbit," with no technical definition of "in orbit," and the technicalities are irrelevant because you don't want to argue your nuclear launch was suborbital. No, it also explicitly rules out any orbital usage whatsoever: "States Parties to the Treaty undertake not to place in orbit around the earth any objects carrying nuclear weapons or any other kinds of weapons of mass destruction, install such weapons on celestial bodies, or station such weapons in outer space in any other manner."
  14. Who will solve this first ?

    Potential energy is in fact the easiest way to solve this problem. If you compute the speed of the water leaving the nozzle, you're doing things the hard way. You have the energy imparted at the bottom as kinetic energy; this is all potential energy at the top, so you calculate how high the energy gets you. It's not just close, it's exact (down to problems of reality differing from spherical cow-land).
  15. Who will solve this first ?

    You made several math errors. 10^6 / 500 = 2000, not 200. So it's 2000 J/kg. You then factored in the mass *again* when you calculated velocity, which is wrong -- it's either 10^6 J = (.5)*(500kg)*(v^2) OR 2000 J/kg = (.5)*(v^2); you don't divide energy by mass to get specific energy and then divide specific energy by mass again to get v^2/2. So the actual velocity is 20*sqrt(10) or about 63 m/s, not .4 m/s. Then t=6.3s, not .04s, and a= -10m/s^2 (not 10 m/s^2); so h=0+63*6.3+(1/2)(-10)(6.3)^2=400-5*40=200.