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Jacke

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  1. Your nephew's illness makes the threat of COVID even greater for him. If he's being even considered for intubation means it's likely a condition with his lungs. If he gets COVID now or later on, things will be worse for him if he hadn't had this disease. You may not have heard of the Bhopal disaster in 1984, where due to safety cuts and incompetence there was a serious leak of toxic gas in Bhopal, India. Over 500,000 people exposed to the toxins, deaths in the thousands. The survivors of that disaster have lung damage. When COVID hit India, the victims of Bhopal had much greater rate of illness, seriousness of illness, and rate of death. Rajkumar Keswani, the local journalist who investigated and published articles on the safety lapses even before the accident, was one of the Bhopal victims killed by COVID.
  2. I think they're too busy looking for a Plan B for the lack of a delivered BE-4 engine. One option being considered: knitting needles and a whole lot of steel wool.
  3. I see no reason for the reliability of Starship in the short term to be better than the current best for other launch vehicles, about 1% failure rate. It may get better, but that will have to be demonstrated. That is about 5 orders of magnitude worse (100,000 times worse) or greater than for current aircraft. Starship has no abort modes for a lot of the potential failures of a launch vehicle, in a similar way as the Shuttle lacked those same abort modes. An aircraft always has the abort mode of becoming a glider, even if it's a poor one and perhaps in a very bad place with respect to its altitude and airspeed. And aircraft are designed and redesigned to have less chance of catastrophic and lesser failures as lessons have been learned from building and operating them, as well as investigating incidents and accidents on thousands of aircraft over millions of flight hours over decades. That's where those 5 orders of magnitude of safer performance for aircraft come from, a whole lot of sweat and blood over time. I don't think Starship will get that for rocketry in under 10 years, as other launch vehicles flying for much much longer haven't gotten to that point. So flying people on Starship before that better safety record is demonstrated without adding in abort modes is condemning 1% of them to die.
  4. Subsidizing costs with funds from other sources is a common business practice to gain market share before later changing things in the future with some combination of now-possible lower costs and higher prices. Sometimes it's done a little, sometimes it's done a lot. Sometimes it works. Sometimes, like what is happening now with Uber, the money runs out and the rate of things falling apart picks up a lot of speed and what was seen by those skilled in the field years ago is now obvious to many, that the end is nigh. Maybe SpaceX makes enough over the lifetime of each launch vehicle article to makes some gross profit. I suspect that's true. But that's about all we can do until there are a lot more numbers in a lot more detail with a lot more confidence and someone independent with a lot of knowledge of the field weighs in on it.
  5. I don't know what SpaceX's costs and per-launch profitability are because that information has not been released, certainly not released in sufficient detail to be audited. As SpaceX isn't a publicly traded corporation, there isn't even good information on any of its cash flows, so only the crudest knowledge of what's going on financially can be made. Here's what I found for relative prices. https://en.wikipedia.org/wiki/Space_launch_market_competition It's a bit of a rambling article, but there's this table of recent costs (with that of the Vanguard launch vehicle thrown in for context). These numbers may not be properly comparable, because I'm not sure enough was done to make sure they could be properly comparable, even to compensate for costs to LEO, ISS, or GTO. Digging into the sources, even excluding Vanguard, they come from a wide spread of years, from 2006 to 2021. I couldn't find a recent source that gave more certain numbers. But I think they're close enough to be at least roughly comparable. The Falcon 9 is priced low enough compared to all competitors to give enough incentive to payload customers to shift, which is about 38% under the next cheapest, Proton. That jives with SpaceX wanting to gain market share. We really don't know what SpaceX is doing to allow it to price its payloads at that cost per kg. We may assume it's at least covering the marginal costs of a launch, but that's still an assumption. I could see that reduction compared to its competitors just by having a much better supply chain. To gain market share, other corporations have done all sorts of things, even for many years, to deliver lower prices than competitors, with varying amounts of risk and various outcomes. Again, we don't know for sure what SpaceX is doing, because they've not put out enough of the data for us to be sure.
  6. Just because the source and nature of the requirements change doesn't mean they can't cause their own issues. As well, we don't know what SpaceX's actual costs are, just what they charge customers. The Shuttle was also planned to greatly reduce launch costs, but it didn't. Starship is unlikely to suffer from the reasons why the Shuttle's costs were so high, but it may have its own cost issues we don't know about. Especially as it's still being developed. The proof of the pudding is in the eating. The Starship pudding hasn't been eaten, so no one is really sure what it will really taste like.
  7. Because the Shuttle's use cases were very similar to some of Starship's. So Starship may recreate in a variant form some of the Shuttle's mistakes. But because the Shuttle was going to exist and was planned to almost completely take over launching US government payloads to space, spy satellite ops and other government payloads massively influenced the Shuttle's final design. The cross-range requirement that drove the large wings on the Shuttle came from the U.S.A.F.'s desire to have it capable of doing 1-Polar-orbit missions from Vandenberg. Without that, the Shuttle could have had much smaller straight wings, as it did on some of the earlier designs. The Shuttle payload bay size and design was strongly influenced by the forecast U.S.A.F. payloads that the Shuttle was planned to deploy and recover. And so many people talk now about Starship taking over the launch market as if it was a fait accompli. Before even a test-article Starship has launched to orbit. Sounds familiar.
  8. My heartfelt sympathy for you, man. This is nothing to like, my reaction to your post is my show of support. I'm over 3 weeks past getting my 2nd Pfizer shot. I'm still keeping my infection control because even though vaccinated means I have a much lower chance of getting infected and it's likely not to be a serious illness, I don't even want to risk that in my life. I also have to worry about 2 friends who I see from time to time, who for their own and very different--but completely illegitimate reasons--won't vaccinate. I tried to explain it, get the importance of getting vaccinated across. I failed with both. So I also maintain infection control to minimize the risk of my friends getting infected. Especially as the leadership of the Province of Alberta, Canada, where I live, are complete idiots who've just barely started to notice that this pandemic ain't over and people are still getting sick, filling hospitals, and dying. The rollback of the Public Health measures for the pandemic has been paused 6 weeks. That's not enough as far too many people are going around with no masks and acting as if they didn't have a care in the world. At least the business employees are still masked. Whether you had COVID-19 or not, the medical advice is to still get the vaccine, as the level of immunity from the illness is random and not necessarily as good as getting the vaccine. So if you've not been vaccinated, please get vaccinated. It may save your life and the lives of others. If you've not do so, as well please consult a doctor about what appears to be post-COVID symptoms.
  9. This is likely impossible to be done in a short-term brute-force manner. It will take decades and many different spacecraft designs to have them even approach some of the reliability of aircraft. And there will always be major differences. Aircraft are an extra level more complex than any ground vehicle, because: Aircraft operate in 3 dimensions instead of ground vehicles' 2 dimensions plus rolling terrain. Flight incidents and faults are often more fateful than those on the ground. Aircraft pilots need much more training and experience and refresher training than operators of ground vehicles. Aircraft costs are much higher than similar costs for ground vehicles. Similarly, spacecraft are much more complex than aircraft. Spacecraft operate using orbital mechanics and have limited maneuverability (delta-V) to change their orbit. Thus spacecraft need to use launch and maneuver windows (and countdowns to them) to get more optimum trajectories to make the best use of that delta-V. Spacecraft systems push technologies and designs closer to the limit of current best available. Thus spacecraft reliabilities even for the best and most mature designs are much much worse than for aircraft. Spacecraft costs are much higher than similar costs for aircraft. Some of these differences may be reduced in the future, as they have been in the past. But that's not going to happen overnight or in a year. And some of the differences will always remain. People often don't appreciate how much government research (e.g. the National Advisory Committee for Aeronautics (N.A.C.A.) formed in 1915) and two World Wars and the Cold War pushed the development of aircraft. Many models made in the hundreds or thousands and put through the torture test of war and near-war. Much was learned from each one and some of that became common knowledge used for later designs. One example, the Sopwith Camel, itself the near culmination of World War 1 aircraft development, had 5590 units produced, but from first flight (1916 Dec 22) to its retirement (1920 Jan) was barely over 3 years. The Boeing B-52, which others have mentioned, was itself the culmination of World War 2 and post-War bomber then jet-bomber design, as well as several models of B-52, of which now only the B-52H's are operated. That's produced airframes that will likely see near a century of service, but it was a long expensive path to get to that level of perfection. Pushed and financed by Cold War concerns and budgets, launch vehicles and spacecraft improved faster than aircraft, but because their role was under harsher conditions pushing the equipment to the limit, that improvement started with much much worse failure rates and still hasn't caught up, with the best launch vehicles still having about a 1% failure rate. Something like Starship is necessary (though because of Starship's lack of abort modes, it should operate uncrewed or people will die). If it is still in service in 25 years, then it's the Shuttle all over again: a development vehicle operated for too long that should have had a successor built to replace it.
  10. There can't be atoms the size of a soccer ball (about 22cm across). As other have mentioned, you can have neutronium--material only made of close packed neutrons--that size, but it only exists under the pressures in neutron stars. You could make up a scaled-up model, as often there's a scaled-down model made of the Solar System, but especially for atoms and smaller, that's a bad idea, because it makes you think of it as something like the ~1m sized stuff around us, where things of atomic sized and smaller behave very differently. You can't think of scaling the atoms without scaling the wavelengths of light, which are larger than the atoms. So, even the "scaled up" atom couldn't be seen in the usual sense. (Scanning tunnelling microscopes "see" atoms as a voltage measuring quantum tunnelling electrons coming from the observed material's atoms.) So we use numbers, usually in scientific notation. Ie. the soccer ball above, 22cm across, can be said to be 0.22m across, or 2.2x10-1. When those exponents on the ten's get very small or very large, it's easier to use them to understand things. Atomic sizes in a quote from: https://en.wikipedia.org/wiki/Atomic_radius The diameters are twice the radii, so between 0.6 and 6 ångströms, or 6x10-11 to 6x10-10m across. For atomic nuclear sizes: https://en.wikipedia.org/wiki/Atomic_nucleus The atomic nucleus is about 1.8x10-15 to 1.2x10-14m across. As in the quote, that's smaller than the atoms by a ratio of about 26,00 to 60,000.
  11. Because how things are at the atomic and subatomic scales don't act the way things do at the scales you're used to. Things are seen because they either emit light or some other radiation that can be detected or they reflect/absorb and reradiate the light or other radiation and that light or other radiation is detected. "Illuminate" an electron with a single photon and it's no longer where it was--unless the electron was bound to an atom or molecule and the energy of the photon was less than the amount needed to raise the energy level of the electron to the next orbital. The best experiment to get a better feel for how things work and how it's not like it is at larger scales is the famous Double-slit experiment. https://en.wikipedia.org/wiki/Double-slit_experiment Things are different there. More topics. https://en.wikipedia.org/wiki/Wave–particle_duality https://en.wikipedia.org/wiki/Atomic_orbital https://en.wikipedia.org/wiki/Molecular_orbital https://en.wikipedia.org/wiki/Orbital_hybridisation
  12. Yes, but fail cheaply in a test program, not in the main program. Again, look what happened to Shuttle. Look what happen at the ISS last week. Both could have turned out much worse. And if there's something major wrong in the design, it's a lot cheaper to learn in a test program than in a main program. Like the N.A.C.A. and NASA have been doing since 1915. 106 years. And which private industry does too from time to time. I'm a trained tank gunner. Drop me in any tank I was qualified on and I'll be up to speed in a few minutes. Give me about an hour talking to someone else qualified on a vehicle's gunnery system and I'll be fair, but I should have a dry practice and a range shoot to get the skills right. I put you in the Gunner's seat in a turret. Do you know how to do the safety precaution? Do you know how to go to action? Load the weapon (if no other Loader)? Traverse your arcs? Take fire orders? Ready the weapon and lay it on target? Note the fall of shot and report your expected correction? Take the Crew Commander's interrupt with a new correction if the CC gives one. Apply the correction? Do you know the Gunner's 4 responses, cold? Why not? Tanks have been around since 1916. 105 years? But you haven't done this. Could have done it in a game. Or maybe you're a tank gunner in your real life too. But you need to have been trained. And that training came from years of experience and work on the vehicle and to make a training program. I've seen all about doing stuff in space since the 1960's. And some of it has been done, basic assembly and refueling of the ISS with hypergols. But again, I say, you gotta walk before you run. Because jumping into a full blown program means everything better be exactly right and nothing better go wrong. 'Cause that's where big cost failures and lose of life comes from. Sorry, @sevenperforce, I'm out of likes today. That's spot on.
  13. Okay, I will. Would you say...it's bigger on the inside? Or smaller on the outside? Awwww, shucks. I was hoping for Disco Lights.
  14. Blackouts happen more from shortcomings in the power grid that are known about and there's issues why they aren't addressed. Currently, I think the only large scale power storage system that really works is dual water reservoirs at different altitudes: pump water up to store power, run water down through generators to return power. What the grid will likely end up with in ~20 years is nuclear+geothermal baseload power, solar+wind fillin power, and natural gas turbine surge power. Right now I think natural gas turbines are the lowest carbon power source that can provide surge power. Eventually the natural gas turbines could be replaced by a custom reactor design with a rapid surge rating, but I think they will have to be overbuilt as due to transient fission product poisoning, it's easier and safer to surge up a reactor that's been low power for a long time than to surge a reactor that has just been dropped in power output.
  15. Trying to run, either a sprint or worse a marathon, while still working on walking is fraught with risks. Straight out of Zubrin's The Case for Mars and his Mars Direct design: ground checkout and assembly is cheaper and much more reliable than orbital assembly and will be so for a long time. Which is why Mars Direct used 2x Saturn V sized launch vehicles. To first send the uncrewed Earth Return Vehicle to autonomously create the methane and oxygen using hydrogen feedstock and carbon dioxide from the Martian Atmosphere. Then the Mars Habitat Vehicle to take out the crew. And lands near the Earth Return Vehicle for on-surface rendezvous. https://en.wikipedia.org/wiki/Mars_Direct Jumping right to orbital assembly and refueling is making a similar mistake to what was done with the Space Shuttle: trying to make an operational vehicle and process when there's not been enough experimental vehicles and process testing. Look at what went wrong with changing the modules on the ISS just now. And how easily that could have turned out so much worse. This is an area that needs more research, development, testing, and practice.
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