I dont need a compass to know the general direction of North,South,
(South is always best) East and West.I have the good old Sun and the
good old Stars. www.google.com Fourmilab Earthview
cuhulin

"Michael Lawson" wrote in message
...

Okay, it's been some years since I've thought about
this, but are you talking about the wavelength
of Hydrogen when it's luminescent, as if you were
looking in a spectrometer?

Here's an explanation of this wavelength:

http://www.novac.com/resources/solar/solar5.php

Jackie