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About sevenperforce

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    Physics Superhero

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  1. SpaceX Discussion Thread

    Loving pics like these from today's launch: Looking longingly at the old Falcon Heavy animation. All the official SpaceX imagery still has the black landing legs. Any word on whether the Block V legs will have special TPS or something similar, or will they be white too?
  2. SpaceX Discussion Thread

    IIRC, aluminum fins can be repainted and reused after RTLS landings but not after ASDS landings. The highest-energy ASDS landings burn up the aluminum grid fins so badly that they may start to lose control authority. Titanium grid fins have more control surface area and are thus better for all flights, but particularly for high-energy flights because they give the booster an enhanced glide ratio so it can use less propellant for guidance. You're slightly less likely to lose a booster if it has titanium fins than if it has aluminum ones.
  3. One-way ride

    Challenge: Send the doomed Kerbal of your choice on a one-way ride to the destination world, and land him (or her) successfully to plant a flag. Your Kerbal need not return. Lowest launch mass wins. I'll create a separate leaderboard for each destination as they are submitted, but the initial suggestions are Minmus, the Mun, and Duna. All parts must be stock.
  4. SpaceX Discussion Thread

    They are just much darker than the underlying paint. Oddly, I don't see the same for the core. Doesn't make much sense to use titanium fins on the lower-stress side boosters and aluminum ones on the hot-entry core...but idk. Maybe they are running short on aluminum grid fins and so they decided to put their last four on the core because it has the lowest chance of recovery. Or maybe they just hadn't installed grid fins on the core booster when this screengrab was caught.
  5. SpaceX Discussion Thread

    I'm going to go out on a limb and say those ARE titanium grid fins, at least on the side boosters.
  6. Is an Iron-Man suit physically possible?

    Clearly I should have read earlier pages of the thread.
  7. SpaceX Discussion Thread

    As I understand it, the trickiest part of dealing with comet trajectories is that comets lose mass and experience significant braking at perihelion, which really screws up estimates. For something with a perihelion at 1 AU, it should be much more predictable.
  8. SpaceX Discussion Thread

    And terra firma!
  9. SpaceX Discussion Thread

    Grid fins out.
  10. SpaceX Discussion Thread

    MOST BEAUTIFUL SHOT OF THE FLIP I HAVE EVER SEEN All CRS missions will be RTLS from now on.
  11. SpaceX Discussion Thread

    Technical webcast is nothing but the regular webcast without voiceover. No differences in shot or telemetry. Sooty rocket lifting off...beautiful sight! Through Max-Q. MVac chilling.
  12. SpaceX Discussion Thread

    The new strongback is NICE. They are going over the upgrades now.
  13. SpaceX Discussion Thread

    We've got soooooooooooooot!
  14. SpaceX Discussion Thread

    Yeah, just a touch of off-plane inclination will help keep it out of intercepts, but it will still cross Earth orbit now and then. But computing a trajectory which has no Earth encounters for millions of years is not that hard to do. Not when you're SpaceX. Just need a fast computer. HYPE TRAAAAAAAIN
  15. Human Ascension

    You were born with a certain set of predispositions and aptitudes, which will not change. However, you can take steps to train yourself to think analytically, to solve problems, to recognize patterns and non-patterns, and so forth. This is not an easy thing to do, though. The brain's neuroplasticity can really only be altered by one thing -- practice. By repeating the same actions over and over (optionally with the help of a reward-pathway stimulant like caffeine), your brain learns to prioritize and expand certain connections. You should try getting up and doing the same things at the same time every morning. Set an alarm, practice getting up immediately, do the same routine every morning. Solve a sudoku or crossword puzzle if you have a morning public transit commute. Human capacity for memorization is pretty amazing, but again, it MUST be trained. Memorize stuff. Start with the periodic table of elements -- there's Tom Lehrer's famous version, which makes for a nice party trick, if nothing else. Practice mental math; learn how to determine what day of the week any date in history is, and amaze people when you tell them what day they were born on. If you have the opportunity, take a college algebra class or an introductory calculus class. Find a study group, ask for help, and ace the class. If you really want to double down, take a college physics class. Skip the "physics for nonmajors" and go straight to technical physics I. Read voraciously. Gradatim ferociter. Try to exercise regularly. We evolved in a world much more active than the one we inhabit today, and your brain is connected to your body, so it will reap the benefits of exercise. Avoid hacks and hype trains. If it's easy, it won't alter your brain. If it's tough, and takes a lot of practice, it will. The only legit "hack" is caffeine. Caffeine hijacks the reward pathways in the brain and helps form new neural connections associated with concurrent activities. However, the effectiveness of this does not scale with the amount of caffeine you ingest, so don't live off espresso. Instead, try to drink a limited amount of caffeine (tea is fine if you don't like coffee) at the same time every day to reinforce the routines you want to practice.