[meteorite-list] Different colors of meteors/shooting stars

[Chris Peterson]

Hi Jim-

As a rule, you can't tell much about a meteor's composition from the 
visual colors observed. The eye is a lousy spectrometer!

The optical output of a meteor consists of hundreds of component 
emission lines, possibly a blackbody component in some cases, and some 
strong atmospheric emission lines. The visual effect is something close 
to white, sometimes with a color cast provided mainly by atmospheric 
ionization. While there are a handful of strong emission lines commonly 
observed in spectra, these are very narrow and therefore represent only 
a small part of the total luminous energy, which means they don't have 
much effect on the color ("color" being a physiological phenomenon, not 
a physical one).

This isn't to say there might not be some cases where meteoroid 
composition is reflected in the color, but you can't make any 
generalizations.

Chris

*******************************
Chris L Peterson
Cloudbait Observatory
http://www.cloudbait.com

On 9/9/2013 10:38 PM, James Masny wrote:
> Good evening list.  Sorry if this has been discussed before, but are
> different colors of meteors streaking through the atmosphere
> indicative of certain minerals burning up?  And what color represents
> what minerals?  I remember the 2001 Leonids, and seeing so many
> different colors - pink, blue, white, yellow, green, orange.  The
> other night, I was outside, and I caught 2 fireballs, 1 changed color
> from yellow to red, another from white to yellow.
>
> All the best
> Jim