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Joined 2 years ago
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Cake day: July 15th, 2023

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  • So…you’re gonna have to define what 'into space" means. 160km is the bare minimum for LEO (its still low enough it’ll degrade, but not so low that you can’t make a full orbit.) the ISS is still in LEO, and still requires some occasional burns to lift it back into orbit at 400km. To get above the atomosphere so you can (mostly) float endlessly in space, you’d need to go to 1,000km

    Pick one. that’s how high you need to be.

    If you want to just technically reach orbital speeds… you could do that at sea level by going about 7.9 km/s. there’s a small problem of air resistance causing you to burn up and, if you somehow survive that, well, here’s mountains to go splat into.

    If yo wanted to orbit at 160km’s amid musk’s space junk… that’s about 7.8km/s, 400 is about 7.67, and 1000 is about 7.35.

    There are some systems that may or may not be viable in the future that don’t rely on rockets at all, for example, the launch loop which is basically a cable held up by making it rotate really fast. (yeah. talk about whacky.) This thing, as propose, is 60km high and several thousand km long. The idea is that you lift up a mag train and then that mag train accelerates at a comfy 3g. You then use relatively inexpensive kicker motors to circularize your orbit as you reach apoapsis (aka, the point of an orbit that is furthest away from the body you’re orbiting.) This raises (or lowers, depending on which way you’re pointed,) periapsis, which is the closest point.

    The thing about ramps, though, is that if your rocket car is already accelerating at 3 or whatever g (most modern launches push 3-4g, mostly limited by the squishy payload.)… you don’t really need a ramp, and trying to use one anyhow just introduces more inefficiency into the system.

    The point of the launch loop is that it gets us off dumping shit loads of CO2 and other greenhouse gasses- it can be powered by nearly any kind of power (though nuclear is the proposed plant,) and the train is accelerated by riding eddy currents off the loop itself.

    Edit: there are other, more reasonable methods for a non-rocket launch, but launch loops are basically a ramp. so. there.







  • And I’m saying “probably not”. If you step out into direct sunlight, you feel warmer because you’re absorbing heat from said sunlight.

    You don’t generally feel warmer because you’re in a well lit room. (Though you do feel warmer if the colors in that room are warmer reds and oranges compared to cooler colors like blues and greens.)

    If there’s enough light on you to feel warmer, it’s likely because the lights are warming you up (like stage lighting for news anchors.) rather than an illusion or placebo or whatever you want to call it.