NASA will test SpinLaunch's ability to fling satellites into orbit

Re:NASA will test SpinLaunch's ability to fling satellites i... by modeless on Thursday April 14, 2022 @04:24PM (#31032798)

The problem with this is if you toss a chunk of raw steel, no matter how fast or at what angle, it will always simply fall back down [1]. The minimum payload for this system absolutely requires a (extremely robust) rocket engine and propellant and avionics to circularize the orbit at apogee. That's the only way to achieve orbit. That puts a disappointingly high floor on the cost per launch and launch rate.

[1] Technically, escape velocity is also a possibility. But it's not a useful one, as the payload is still lost.

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Re:NASA will test SpinLaunch's ability to fling satellites i... by nottim on Thursday April 14, 2022 @04:30PM (#31032867)

That only holds true assuming a 2-body (earth and rocket) system - add in forces from the sun or from the moon and you can actually achieve orbit with only a single surface level impulse, although it does require some pretty precise aim.

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Re:NASA will test SpinLaunch's ability to fling satellites i... by modeless on Thursday April 14, 2022 @04:57PM (#31033198)

It would be super cool to use the moon to circularize the orbit. But the orbit you'd get wouldn't be super useful, probably. I wonder about stability as well. And the practicality of achieving the velocity to reach that high, and aiming that precisely. It would be really cool to see some analysis of that.

Another out-there idea would be to shoot things at a space station that had a giant catcher's mitt or something. Would it be possible to design a decelerator that would work? And to hit it precisely with a dumb projectile from the ground?

A third possibility would be to recover and reuse the rocket engines en masse. Not sure how it could be done in a way that was cost effective though.

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