Episode 13: The speed of light

Learn more about this cosmic speed limit, including how you can measure it at home.

Questions, comments, or ideas for future episodes? Contact Liz and Bill at
cosmicadventures@astronomy.com

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STEVE MURAGIAH SR from SWEDEN said:

Facinating...hope someday we can travel at that speed...we will be among the star in no time.......thank you for the lesson.....my son understood better.

Submitted: 5/4/2013 2:16:28 PM (CST)

PETER SOJKA from PENNSYLVANIA said:

If white chocolate were used instead of dark chocolate, your result would be closer to C because you would eliminate any interference from "dark matter".

Seriously, love the videos, whimsical or otherwise. I am entertained plus learn something from each one.

Submitted: 3/30/2012 10:54:37 PM (CST)

LIZ KRUESI from WISCONSIN said:

In response to Aristedes Mendes: The next video will be out in just a few days. We're happy to hear that viewers are awaiting the next episode!

Submitted: 3/27/2012 10:35:52 AM (CST)

ARISTIDES MENDES from UTAH said:

when is the next video coming out? waiting ....

Submitted: 3/24/2012 12:11:22 AM (CST)

KENNETH E EBELING from IOWA said:

I loved this program. You did leave out one important person, Albert Abraham Michelson. Remember he did the speed of light on two mountain tops in California. I looked up the names of those mountains, Mount Wilson and Lookout Mountain. Adding his work would realy brighten up the video and put a new light on the subject. This would also be good in the science classroom as an experiment. KEN

Submitted: 3/23/2012 11:58:38 AM (CST)

GARY STEVENS from MINNESOTA said:

Yes, the speed of light is a fascinating topic, but what I'd really like to know is what is the speed of dark? Is this somehow related to dark chocolate?

Submitted: 3/16/2012 6:31:31 PM (CST)

ANTHONY BARREIRO from CALIFORNIA said:

If a dog were travelling at close to speed of light, how long would its ears appear to a stationary observer?

Submitted: 3/16/2012 2:20:58 PM (CST)

DYLAN ZAWADA from NEW JERSEY said:

how come the wavelength in the chocolate bar was faster than the speed of light it self still this vidieo is cool and tasty

Submitted: 3/10/2012 3:57:18 PM (CST)

WILLIAM H THORNBURG II said:

Yea! Another reason to buy a bar of chocolate!!! Thanks for the awesome properties-of-light demos. :)

Submitted: 3/2/2012 12:44:34 PM (CST)

FRANCISCO SILVA from NEVADA said:

I think in the course of the light we have to investigated more because I think things onother sing can be faster then light in the space.
for example
the dark an unexplored area...

Submitted: 3/2/2012 12:41:24 PM (CST)