Basically, a big long rope with a rock one end and a hook at the other end, spinning freely in space.

Also called a Sky''''''Hook or a rotavator.

''Also a classic trick to play on a new apprentice at a factory: send him to the workshop to ask for a sky hook or similar 'impossible' item.''

'' This is called a SleevelessErrand. ''
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The most often-proposed SpaceHook design:

Put the SpaceHook in LowEarthOrbit (LEO) so that the hook periodically dips down into the atmosphere.

Spin the SpaceHook so that the hook has a wind speed close to zero at the instant the hook reaches its lowest point.

You take your cargo in some modified airplane, timing your flight so you get to the hook right at the lowest point. Attach the cargo to the hook. Then as the SpaceHook continues to rotate (pulling your cargo out into LEO), let go of the hook at "just the right time" to put the cargo close to the desired orbit, then use rockets for final fine-tuning.

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A SpaceHook could get stuff into space and back much more cheaply than using rockets the whole way.
There are big up-front costs, but they are much cheaper than a full-size SpaceElevator.

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(CategoryHardware ?)
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