Remember back in high school (or college) when you were learning about units of measure and how the length of a Meter was defined by a metal rod stored in a safe guarded by rugged soldiers somewhere in Europe?  Well not any more.  I was suprised to learn that the length of a Meter is now defined by the distance that light travels in one second.

I found this out after hearing on NPR that the Nobel prize for physics was awarded today for three scientists' work with optics and quantum mechanics.  The reporter mentioned that the speed of light can be measured so accurately that the length of the Meter can be most accurately defined using the speed of light.  This is now the way the Meter is defined in the science community.

Maybe this is old news, but I never heard about it until today.  Very cool.