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Comment by JKCalhoun | Hacker News Reader

Somewhere I read (was it Clarke?, Asimov? ... who knows) that you could pitch a baseball on the surface of Deimos, wait some number of hours (minutes?) and it would have orbited and returned from the opposite direction, you could then hit the ball with a bat and some time later catch it on the re-orbit and declare yourself out.

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Escape velocity is just around 5 m/2 so don't pitch it too fast or it won't come back! Even a Little League pitcher should be able to throw a ball at 20 m/s or so.

It should be possible to jump up off the surface at this speed too eh

Probably difficult to do it as a high jump, but a person on a bike hitting a small ramp could do it no problem, assuming you could even find enough traction to get going fast enough in such light gravity.

Skateboard and fire extinguisher.

No need for skateboard in that gravity.

If you can jump around 128cm high on earth (measured at your center of mass), you can accelerate yourself to more than 5m/s upwards.

Most healthy adults should be able to do that, especially with a running start. It's about as much as you need to do to get a passing grade in PE at age 16 in most places. Also in this hypothetical you don't have to fight much gravity while accelerating - only inertia.

Getting a running start would be a problem when each step launches you into the “air”.

Pretty sure I can still do 100 m in less than 20 seconds, so...

(Except, as others have said, I wouldn't have the traction to accelerate.)

I think it was Carl Sagan and Phobos. Not Deimos.

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