ISEN-ASTC-L is a service of the Association of Science-Technology Centers
Incorporated, a worldwide network of science museums and related institutions.
*****************************************************************************

> -----Original Message-----
> From: Informal Science Education Network
> [mailto:[log in to unmask]]On Behalf Of Wayne Watson
> Sent: Friday, July 18, 2008 4:06 PM
> To: [log in to unmask]
> Subject: Re: Doppler Shift
> 
> 
> ISEN-ASTC-L is a service of the Association of 
> Science-Technology Centers
> Incorporated, a worldwide network of science museums and 
> related institutions.
> **************************************************************
> ***************
> 
> An interesting aside to this is that the speed of light can 
> be reduced 
> to human walking speed in the laboratory. It's done by using very low 
> temperatures. I suspect Google may reveal some details and 
> maybe even a 
> video on it.

Whoa. A (rather abstract) animation, maybe. But don't expect video of physicists in cold suits dodging light beams. Most of this stuff takes place for nanoseconds inside a pinhead-sized glob of Einstein-Bose condensate, or some such. Hmmm... what a great spoof video that would be... flailing limbs throwing off Cherenkov radiation... people walking through walls like Kitty Pryde...

Yes, "the speed of light" is more variable than we're taught, but I'm talking about the intergalactic medium, here. The intergalactic medium is as close to "empty space" as the Universe gets.

In any case, even if, in passing through a thin cloud of plasma the light is slowed ever so slightly, as far as I understand it gets back up to full throttle as soon as it emerges from the other side. No redshift or blueshift.

gotta go get ready for the museum sleepover this weekend...
http://www.hrm.org/calendarlist.html#onesmallstep

Marc Taylor
Coordinator, Andrus Planetarium
Hudson River Museum
511 Warburton Avenue
Yonkers, NY 10701
914 963 4550 x223
Fax 963 8558
[log in to unmask] 

***********************************************************************
For information about the Association of Science-Technology Centers and the Informal Science Education Network please visit www.astc.org.

Check out the latest case studies and reviews on ExhibitFiles at www.exhibitfiles.org.

The ISEN-ASTC-L email list is powered by LISTSERVR software from L-Soft. To learn more, visit
http://www.lsoft.com/LISTSERV-powered.html.

To remove your e-mail address from the ISEN-ASTC-L list, send the
message  SIGNOFF ISEN-ASTC-L in the BODY of a message to
[log in to unmask]