🚀 go-pugleaf

In article <BrrMJB.Brv@acsu.buffalo.edu> mjb@acsu.buffalo.edu (Matthew J. Bernhardt) writes:

> >Why is the sky blue?

> 	No doubt the quantum mechanical justification of this phenomenon
> is forthcoming...

No quantum mechanical explanation is necessary; there is a perfectly
good classical explanation in section 9.7 of Jackson.  (Jackson,
incidentally, points out that the physical explanation of why the sky
is blue was understood by Leonardo da Vinci, in 1500 or so.)

Summary: the scattering of light by nitrogen molecules is higher for
higher-frequency light.  So the light that we see in the sky, which is
entirely scattered sunlight, is predominantly blue and violet
frequencies.  For the same reason, sunsets are red.
--
Matthew Austern              I dreamt I was being followed by a roving band of
(510) 644-2618               of young Republicans, all wearing the same suit,
matt@physics.berkeley.edu    taunting me and shouting, "Politically correct
austern@theorm.lbl.gov       multiculturist scum!"... They were going to make
austern@lbl.bitnet	     me kiss Jesse Helms's picture when I woke up.