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(meteorobs) color of meteoriod

Hi Norm:
  
Regarding your comments on color of the object. The following is what I
received from the person who is working on the computer model.
 
>>>>>>>
+>I have never seen a truely red meteor either.  The best I've done is
+>red-orange.  But setting that aside, the description above is exactly like
+>an Atlas launch in the early 1960's from Cape Canaveral.  I saw several of
+>those over a five-or-so year period.  This description is distinctly
+>different from meteors, of which I have recorded about 80000 since 1960.

Our proposed daylight fireball meteor is, by necessity, driven by a 2,000
to 4,000 kg meteoroide.  How many fireballs have you personally watched in
daylight which dropped hundreds of multi kilogram meteorites?  I humbly
suggest you research eyewitness reports of such events and you will note
that colosrs such as red and red-orange (which was what Maj. Meyer's saw)
are reported.

Your suggestion of an Atlas as a comparable description is interesting.
Are you suggesting something as big and spectacular as an intercontinantal
balistic missile was used to shoot down Flight 800?   I would like to point
out that if the eyewitness did report something this brilliant, then a
meteor is far more probable than an ICBM.  And at 10 miles in a
sunlight-lit sky, they were not watching a sidewinder.
<<<<<<<<<

I have a suggestion which might account for some of the color variations in
the witness reports.  I note particularly the difference between Major
Meyer's and Paul's accounts (because we are so familiar with these two).
Meyer saw a more orange red while Paul clearly repeats red-red.  Paul was
on the ground looking through a good evening sea-haze while Meyer was a
couple hundered feet up (right?) and further inland.  I would suggest that
perhpas the color was skewed/filtered from the true emission spectrum of
hte meteor by simple Rayleigh scattering of the light.  Rayleigh scattering
is the mechanism by which the sky appears blue and sunsets appear red.  The
mechanism is that blue light being shorter wavelength than red is scatered
(deflected) from its direct path by molecules of gas and very small
droplets of condensed gas (e.g. water) (though scattering by small droplets
is not stricktly Rayleigh scattering-it has a similar and stronger effect).
Anyway, the result of both is that blue light is knocked aside from the
straight line of sight to the emitting object while red light is knocked
aside less.  This tends to skew the color balance of the "filtered" light
by removing more blue and removing less red.  When looking straight at the
emitter, the color is reddened, and the amount of reddening depends on how
much scattering was between the object and observer.  The blue light
knocked aside is what makes the sky blue.  So, with that in mind recall
that Paul was looking through more shore haze than Meyer over dry land and
up a bit, and hence had a stronger scattering filter in place and should
have recieved a redder light than meyer.  Someone up even higher than Meyer
(e.g. in a plane) in good clear sky would have seen the true color balance
which was probably whiter than either meyer or Paul saw....  That's my take
on it for what it's worth.

(P.S., you can notice this for yourself on a good(?) foggy day.  Look at
the color of oncoming car headlights through the fog.  Far back, they
appear dull orange yellow.  As the car gets closer, they shift to a
"hotter" white color as you would see on a clear night. (Yes they also get
brighter, but the color shift is independent of brightness.)

P.P.S. This is nothing like Doppler red shifting which is a relativistic
effect seen only when the observer and emitter are moving at significant
fractions of the speed of light w.r.t. each other.  Doppler shifting
actually _changes_ the color of _every_ photon in the light stream.
Rayleigh scattering _removes_ photons from the stream by sending them into
new directions.   Regards , David -- End of his report

Regards, Lloyd