At some point you have to rely on "givens". You can't go turtles all the way dow... | Hacker News

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		FlorinAndrei on June 15, 2010 \| parent \| context \| favorite \| on: Measure the Speed of Light Using Your Microwave At some point you have to rely on "givens". You can't go turtles all the way down.

JoeAltmaier on June 16, 2010 [–]

Sure you can. Ham operators bounce a wave off the moon. Time the round trip. Speed of light. Or send a blip thru a spool of fibre optic cable, measure the transit time. It CAN be directly measured.

sliverstorm on June 17, 2010 | [–]

So how did you figure out how far away the moon was?

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