Comment on If you were to launch a rocketship parallel to the earth, on wheels, how big would the ramp have to be to get it into space?

• FuglyDuck@lemmy.world ⁨4⁩ ⁨days⁩ ago

  the longer you spend at sub orbital speeds, the longer you’re spending energy to counter gravity. Building a ramp and lifting it up slowly would only be feasible if you had cheap power to do it. but over all, you’re still using most the same amount of energy to get there anyways.

  also… if you’re going to slow, you’ll just fall back down…

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• makeshiftreaper@lemmy.world ⁨4⁩ ⁨days⁩ ago

  Some more physics things, every planet has a limit on how high the tallest possible mountain is based off their surface gravity, the type of rocks present in the crust, and thickness of the crust. On Earth it turns out that limit is pretty close to Mt Everest’s height. Space is still about 50 miles above Everest so I don’t think humans could build this ramp with our current understanding of physics

  If you want to go to space slowly then you can just do what Felix Baumgartner did and take a special type of balloon to get into space. Unfortunately, if you’re not traveling 25,000 mph relative to the surface of the planet, you’re going to fall back to the planet. Just like Felix did

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• null_dot@lemmy.dbzer0.com ⁨3⁩ ⁨days⁩ ago

  I don’t know anything about physics and orbits other than what I learned from Simple Rockets on android, but from what I know it’s always about how fast you’re moving rather than how far away you are.

  You’re thinking that if you get far enough away then earth’s gravity won’t effect you any more, but it’s not really like that. The effect does diminish as you move further away (inverse square law!) but you’re still going to be effected, as in “how far away from this star do I need to go before I can no longer see it?”

  In practice, you’ll become far more effected by the Sun’s gravity than you are by Earth’s gravity, long before you really escape Earth’s gravity.

  That’s why the answer to this question is how fast you need to go, rather than how high you need to be. If you could fire yourself out of a canon at 25,000 mph and were uneffected by atmospheric drag you’d leave Earth’s area of influence faster than Earth can haul you back - so you escape.

  However, if you were floating stationary 25,000 miles from Earth and uneffected by any other cellestial bodies, you’re going to fall down Earth’s gravity well.

  Again, I don’t really know anything about orbital mechanics so I suppose someone and their LLM will be along shortly to tell me how wrong I am.

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• Witchfire@lemmy.world ⁨3⁩ ⁨days⁩ ago

  It would probably have to spiral outwards around the Earth like the world’s greatest off-ramp

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• pinball_wizard@lemmy.zip ⁨3⁩ ⁨days⁩ ago

  Yeah but like what if the ramp went past the exosphere?

  I think you’ve designed a horizontal space elevator. I like it.

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