This recent meteor over the midwest. Reports described it at blue / green. I have seen blue / white, red and yellow meteors. I presume red means iron, green means copper. Can meteoritics or meteor specialists (or whatever you call them) say a lot about the content of a meteor based or the color it makes during entry?
Absolutely, it's the same as heating up metals with a blowtorch. The colour of the flame tells you what is present. Wikipedia actually has a handy list giving an indication of the significant elements present:
- Orange-yellow (sodium)
- Yellow (iron)
- Blue-green (magnesium)
- Violet (calcium)
- Red (atmospheric nitrogen and oxygen)