[meteorite-list] Very Bright Fireball Over Europe on Halloween Night

From: Marco Langbroek <marco.langbroek_at_meteoritecentral.com>
Date: Wed, 4 Nov 2015 09:05:57 +0100
Message-ID: <5639BC65.5090404_at_online.nl>

> A lot of folks say it looked green to them, which means it may have been
> metallic;


It is a perpetuated misunderstanding that meteor colours are primarily due to
their composition. It's a science myth inspired by High School Bunsen burner
experiments that appears hard to kill.

While composition in some cases does have some influence on the colour, it is
actually the composition of the atmosphere that is usually dominant for our
perception of meteor colours.

That certainly is true for green colours. Meteor spectra show that meteors
usually are very strong at the "forbidden" Oxygen line at 5577 Angstrom (557.7
nm). This line is due to atmospheric Oxygen, the same atmospheric Oxygen
exitation line also responsible for the green colours of Aurora.

So green meteor colours are likely atmospheric in origin and say little about
the meteoroids' composition.

- Marco


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Dr Marco (asteroid 183294) Langbroek
Dutch Meteor Society (DMS)

e-mail: dms at marcolangbroek.nl
http://www.marcolangbroek.nl
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Received on Wed 04 Nov 2015 03:05:57 AM PST