• ch00f@lemmy.world
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    18 hours ago

    The issue is not going up, it’s going over. If we only cared about the private sector getting people into space, that happened on a fully reusable vehicle twenty years ago.

    The problem is getting things to stay in space. Not trying to Elon-stan here, but getting a rocket into orbit is many fold more difficult than just getting into space.

    • gandalf_der_12te@discuss.tchncs.de
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      3 minutes ago

      Yeah, if by “going over”, you mean accelerating in the horizontal direction, then you’re right.

      Just to illustrate this: Consider we want to put 1 kg of mass into orbit.

      First, we have to raise it by 100 km. That requires 1e6 J = 1 MJ of energy (formula is m*g*h).

      Then, we have to accelerate it sideways, to a speed of 8 km/s. The energy to do that is 32 MJ (formula is ½*m*v²).

      So, most of the energy (97%) is actually in the sideways movement.