Speed of Light

The maximum velocity for everything in the universe; 186,282.397 miles (299,792.458 km) per second, or fast enough to go to the Moon and back in less than three seconds.

Radio Programs

More Moon and Companions Turning on some far-away lamps Wednesday, June 27, 2012

More Moon and Jupiter Charting the limited speed of light Wednesday, October 20, 2010

Distant Dubhe

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Chasing the great bear

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