Thomas O'Brian

Sep. 24, 2010

Testing Relativity With Better Clocks

With a precise enough clock, it's possible to test the time-dilation effects predicted by Einstein's theory of relativity -- without a space ship.

time, relativity, clocks, einstein

Feb. 29, 2008

Telling Time: Leap Year, Leap Day

This Friday is a date that comes only once every 28 years - Friday, February 29th. We'll talk about leap years, leap days, and the finer points of telling time.

time, date, leap year, calendar


Michael Pollan Talks Plants and Food

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Happy Thanksgiving!


Mystery Box

Meet The Balloonatics

\tIt's crunch time for the 'balloonatics' at Macy's Parade Studio. The balloons themselves, which are designed and fabricated in a warehouse in New Jersey, are getting their final checkup before the Macy's Thanksgiving Day Parade. John Piper and Jim Artle take us around the studio and spill the secrets of inflation, explain how to calculate whether your balloon will float, and explain why the balloons look better after a little time in the sun.


\t \t\t \t\t\tDownload MP4 | Watch on YouTube. \t


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