p1t1o

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About p1t1o

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    Just some guy, y'know?

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  1. @SuperFastJellyfish One of the best lines ever written - more so because of the implication that it is based on empirical observation
  2. Related information: Missiles are starting to appear on the market with more and more novel methods of increasing lethality. For example, the MBDA "Aster" series of SAMs, includes models with solid fuelled "divert" thrusters (referred to as "PIF-PAF"), which fire perpendicular to the missile body, acting at the centre of gravity, that can fire in the terminal phase to decrease miss distance and increase pK. https://www.mbda-systems.com/wp-content/uploads/2015/07/ASTER.pdf Further details are hard to come by, one presumes much is classified. Luckily much has been declassified about cold war projects (but not everything, mind) so there is a wealth of information here. And as it happens, your scenario describes a niche for everyonesfavorite terminal defence king: the Sprint missile. The sprint missile is essentially the reverse of a nuclear reenty vehicle and thus it manoeuvres essentially in the same envelope. Accelerating at 100G at liftoff, it reaches Mach 10 in about 2-3s. First stage manoeuvring is done by vectoring the main thrust using fluid injection (rather than using physical vanes, cold gas is injected into the exhaust which causes dynamic effects that deflect the main plume). Second stage manoeuvring is done with small aerodynamic fins, much with any other missile. At hypersonic speeds, and in the lower atmosphere, aerodynamic lift is extreme. Sprint could manoeuvre at 50-100G laterally and had to be "de-accuratised" because it kept physically hitting the target warheads (it was intended to detonate a neutron bomb - oh yeah, the Sprint missile is the reason neutron bombs were invented, none of that "preserve the infrastructure" junk - in close proximity, nuclear warheads are surprisingly hard to guarantee a kill). This will be a good read for you, I think: http://www.decadecounter.com/vta/pdf/ABM Research & Development at Bell Laboratories - Project History [1975-10].pdf Sprint missile: Note how it looks pretty similar to a nuclear RV Note how small the 2nd stage control fins are
  3. It saves me a lot of time to just ignore videos and suchlike from social media, so I havent and wont watch the video. Not like a "I wONT" kind of way but in a "why would I bother" kind of way. But oh my no, that information is incredibly bogus, from what you describe. Perfect example. Rough guide - if one has a question on something that is making the rounds on social media, google it. Just google the question and pick the link that looks most like a scientific journal. Put "pubmed" or "ncbi"in the search terms. Ignore anything from any kind of site that people want "clicks" from or any other kind of potential income. When people are paid based on the popularity of their videos, accuracy is FAR from their top motivation. Save yourself some time. For the record - much is still unknown specifically about SARS-cov-2, there just hasnt been enough time for studies to complete yet, but similar coronaviruses (and SARS-cov-2 is not expected to diverge significantly) start to get deactivated at a high rate around 55-56degC. https://www.who.int/csr/sars/survival_2003_05_04/en/
  4. Buffy-1 or Buffy-2? https://www.enzolifesciences.com/ALX-804-128/baff-human-monoclonal-antibody-buffy-1/ https://www.enzolifesciences.com/ALX-804-131/baff-monoclonal-antibody-buffy-2/ I love the internet
  5. Yes, LH2 has its drawbacks, I shouldnt have gotten so hung up on hydrolox when I said What I should have said was "cheaper and simpler to use a larger quantity of more conventional fuels than F/Li/H" I meant to stress that I cant see any advantage with moving [from any given propellant] to F/Li/H when we have propellants which already work, for the sake of a few tens of Isps. Anyhoo, the OP question was "why not F/Li/H" and the given reasons ARE the actual reasons, for better or worse. It keeps blowing off bits of rocket scientist.
  6. Yes with an "if", No with a "but" https://www.bbc.com/future/article/20200327-can-you-kill-coronavirus-with-uv-light
  7. Its dangerous in that its a flammable rocketfuel yes, but what makes you say it is more dangerous - or more impractical - than a triple-fuelled rocket with fluorine and lithium?
  8. PSA: Depending on the surface, and the conditions, the virus can survive for hours to days, and traces have been found after more than two weeks in some instances. The general guidance is that the risk is significantly reduced after 72 hours. https://www.nejm.org/doi/full/10.1056/NEJMc2004973 https://www.gov.uk/government/publications/covid-19-decontamination-in-non-healthcare-settings/covid-19-decontamination-in-non-healthcare-settings
  9. Because lithium, fluorine and hydrogen? Just....no. Even if everything works perfectly, the launchpad is now a toxic deathtrap. Cheaper and [much] safer to simply build a larger hydrolox rocket - and why wouldnt you?
  10. Can I do a prescient one? I have a broken rib at the moment - nothing to do but try not to stress it until it heals. But if I do contract COVID-19 with its racking cough, Im in for some pretty severe agony.
  11. @5thHorseman There are TWO sided floppies? What hyper-space-1999-from-the-future technology is this? Im also "return of the jedi" years old
  12. I'm "AOL has sent us another 280 hours of free internet on a floppy disc" years old
  13. There is a great deal of handwaving and opinion here, how serious do you want these answers to be? Because even if you just want to reach "hard scifi" levels, there is a huge amount of work to flesh out your ideas - and to see if they actually work. And all this is before we consider how unbelievably difficult anti-iron is to come by.
  14. Newtonian physics and Einsteinian physics are both approximations of the same thing - physical reality. The question "Why is the orbit behaving in a newtonian fashion?" is the wrong question - it has no meaning. The orbit is behaving in a real, physical fashion and we use Newtonian physics to describe and predict it. Nature doesnt follow our theories, our theories follow nature. For regimes below relativistic (say, the problem involves no velocities above 0.1c), both Einsteinian and Newtonian physics are extremely accurate - but Einsteinian physics is harder and more complex, whilst Newtonian calculations can mostly be done in your head, so we would always use Newtonian here. When velocities approach relativistic regimes, Newtonian physics loses its accuracy (like trying to measure the temperature of the core of the sun, with a mercury thermometer, the results - vast expansion of mercury vapour - make no sense to the scale printed on the side of the glass tube) so we would use Einsteinian.