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[deleted] t1_j1vf608 wrote

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[deleted] t1_j1vgnvo wrote

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[deleted] t1_j1vifvu wrote

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Bbrhuft t1_j1xphn6 wrote

Meteorites entering the atmosphere don't burn, it's an entirely different and quite complex process.

The high energies and temperatures involved creates dense a plasma surrounding the meteorite composed of excited (electrically charged) molecules, ionised air plasma and ionized meteorite plasma, with temperatures between 2,700 - 50,000 kelvin (some sources say up to 100,000 kelvin).

Magnesium plasma (singly ionized magnesium) in particular is responsible for the green color of some meteors, ionized magnesium (Mg I) emits green light between 517-518 nm.

The Peekskill meteorite created a noticebly green fireball, it was a H6 stony iron condrite (containing orthopyroxene with 17% magnesium).

Other emission lines include ionised iron (blue emission lines) and sodium (yellow-orange emission line), as well as innumerable emission lines from aluminum, calcium, chromium, hydrogen, nickel, silicon, and manganese. These many emission lines merge to form a continuous spectrum (white meteors).

The relative contribution of the main emission lines of iron, magnesium and sodium control the color of meteors, which emission (colour) predominates is related to the meteor's composition and velocity; fast meteors (>30 km per second) ionize magnesium and are green, moderate velocity meteors (30-15km per second) ionize iron and are blue, and slow moving meteors (<15km per second) ionize sodium and are yellow-orange.

Atmospheric air is also ionized at the very high high temperatures involved. Emissions lines from nitrogen, oxygen, and nitrogen oxides are also detected. These are responsible for Persistent Trains, a long lasting dim afterglow of a fireball that can last a few seconds to minutes.

>Subsequent air collisions are predominantly with the vapor cloud (Padevet, 1977), causing atomization and ionization of meteoric vapor and air molecules. In this process, impact excitation, leads to much of the observed optical emission of meteors (Öpik, 1955, 1958).

There's also black body emission from cooling meteoric dust.

Ref.:

Jenniskens, P., 2004. Meteor induced chemistry, ablation products, and dust in the middle and upper atmosphere from optical spectroscopy of meteors. Advances in Space Research, 33(9), pp.1444-1454.

Taylor, M., Gardner, L., Murray, I. and Jenniskens, P., 2002. Jet-like structures in Mg (518 nm) images of 1999 Leonid storm meteors. In 34th COSPAR Scientific Assembly (Vol. 34, p. 2917).

Edit: Here's a book from the late 1950s about the physics of meteors...

Physics of meteor flight in the atmosphere by Ernst Julius Opik

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zu7iv t1_j1xalfp wrote

In general, everything /u/Synaps4 said. That being said, as most meteorites are made of a variety of atom types that probably have different ionization energies, my bet is that you would see white as a default - as is consistent with personal meteorite viewing experience.

For this picture, my bet is Photoshop.

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ztoundas t1_j1xeyc9 wrote

I've seen green meteorites a few times this year alone. They're not that uncommon.

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karantza t1_j1y7oeg wrote

I've personally seen green and pink meteors that my memory at least recalled as being this vivid. I doubt this image was processed any more than any other night landscape photograph would be.

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