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Re: (meteorobs) Meteor color

In a message dated 96-10-06 12:28:17 EDT, you write:

<< Interesting discussion on meteor colors.  Have always found the meteor
color
 to be an intriguing part
 of meteor observing.  Although yellows and whites seem to be more common,
 have also seen 
 greens, red (1), and blues.  Aside from the atmosphere providing the color,
 couldn't the meteoric
 material itself be providing the color of the meteor?  If I recall my
 chemistry right, sodium burns
 with a yellow flame, barium with a yellow-green one, calcium with red,
 potassium with violet, and 
 so on.  Couldn't these specks of dust be revealing their composition each
 time they streak across 
 the sky?
  >>
_____________________
Jun,
The elements present in a meteor probably do give off the color of the
burning element, but the colors actually seen may be from a combination of
sources and reasons. There are probably some blending of colors as well as
masking of colors. No doubt, if a good spectra is taken, the signatures of
the various elements present will show up.  A speck of dust  may not have
enough energy to  produce enough color of any particular element to be
visible to an observer on the ground.  Besides producing a color, a meteor
needs to be able to produce a significant amount of any color for the human
eye to register as a color...if not, they become white or yellow depending
upon the individual. As to everything, there will be some exceptions.  I do
recall seeing a few years ago a +2 or +1 meteor that was as green as the
grass on a well kept lawn. This was such a unique green that I've always felt
that it must in some way was an indication of it's composition...But ?

Just for grins, I went thru the Fireball reports from FIDAC for all of
1994...the FIDAC NEWS Volume 2, No.1 thru 6 and tabulated the colors
reported. This probably represents roughly over 200 fireballs world wide from
a variety of observers...although several people contributed to the most
sightings.  If the color was reported as multiple such as Blue/green...I
recorded both colors separately. This wasn't a very scientific survey, but
just a source of some numbers to kick around. What I got was as follows:

White = 174
Yellow = 162
Blue = 127
Green = 117
Red = 55
Orange = 45
Violet = 3
Silver = 1
Total = 680
These numbers can be interpreted anyway one would like.  You might want to
combine the whites and yellows as one group. Blues, Greens and Violet as
another and the Reds and Oranges yet another... As for the Silver....a
"group" all it's own.
Then I would come up with:

Yellow/White = 336
Blue/Green/Violet = 247
Red/Orange = 100
Silver = 1
Total = 680

One thing I did note while tabulating.  It seems that certain individuals
have a preference for certain colors.  Roughly explaining, I will see a lot
of Greens, Lunsford will see a lot of Blues, Micu seems to see a lot of
blues, and Wolf will see a lot of yellows. This doesn't really mean much
other than to show that there is some bias in color determinations ...whether
it be due to biological reasons/interpretations or physical reasons in the
sky. Again, showing the difficulties in interpreting color from many people
as sources. 
George Z.