About a week ago, a meteor passed over, east to west, after sunset, I heard a sonic boom, and looked up, just in time to see the thing. My question is; the colors; this one was yellow-orange, then it fragmented, and the fragments changed color as they approached the tree line. They went from yellow-orange to green to blue, and then pale yellow and disappeared into the trees. I think this one was close because of the sonic boom and the relative motion of the fragments. In addition, the abundance of the really small pieces, moving rapidly in relation to the major pieces told me that it was close.... I wanted to get expert opinions about the colors, all that I could think of was copper and iron/nickel, or whatever carbonaceous chrondite is actually made of.....what is the exact cause of the color change, alloy or temp. changes??? Does density of atmosphere affect the colors??

Thanks,

Dale in Ala

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"Ad astra per aspera"

I definetly am not an expert but I do tend to be colorful. :wink:

Composition of the meteor and the different gases encountered at each level in our atmosphere should account for it.

The Leonids tend to be green and the Geminids tend to be yellow. Ionized oxygen (OII, OIII) produces green emission and ionized hydrogen appears red.

Here is a colorful meteor .

[There are those hear who know, I am sure. ]

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Lighten up! This is a stellar board! Author: duh.

"The Sun, with all the planets revolving around it, and depending on it, can still ripen a bunch of grapes as though it had nothing else in the universe to do..." Author: Galileo supposedly.

This one was close, and at the far end of re-entry, so make of that what you will, I did not see the entry or its subsequent track, just the emergence from 5000' overcast and fall from that point.....The was a flash of light overhead in the clouds virtually simultaneous with the sonic report, but what that looked like I cannot say, as it was obscured by cumulo-stratus or stratus clouds......

Dale in Ala

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"Ad astra per aspera"

re-entry?

The sonic boom would have taken about 5 seconds to go the 5000'

Sounds more like a Roman candle than a meteor(ite)

Hi and welcome vonmazur.

My understanding is that below 5000ft meteors/meteorites would be fairly cool, not incandescent, so I don't see how they could produce a trail at that altitude and the air density is too great to be ionised. Sonic booms may be recorded by any local earth tremor sensing station near by and perhaps you could get someone to check that time and date for you.

We are starting to see a few Perseids as they build up for the maximum expected on 11/12th August and I witnessed a few around 00.30 GMT (UT) on Wednesday 3rd. although they were all a bit camera shy. None were spectacular or colourful. One fairly bright one did leave a very brief persistent trail but was out of the camera FOV at the time.

Re-entry does imply something went up before it came down and would normally be applied to space junk but random stray meteors, often flamboyant, can impact the Earth's atmosphere at any time. Without knowing exactly what you saw it's difficult to be absolute but I too suspect terrestrial rather than celestial pyrotechnics.

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By asking questions we sometimes get the wrong answers, from wrong answers we learn to ask the right questions.

I remember the Dec. 2, 1999 bolide over central Alabama--and the one in Nov. 11, 1986--remember those? Those were around the half kiloton range IIRC.

Alabama gets a lot of them--or so it seems, that is.

This one was above the overcast, and then fragments fell nearby, still hot I guess.......This one is wierd in that it did not come out of the Northwest, it was retrograde to the usual ones here.....

Dale in Ala (Stars fell on Alabama.......)

__________________
"Ad astra per aspera"

Extrasolar--cometary?


OT. I recall folks who claim they heard an aurora. I think some of the infrasound might have positive proof.

Don't know.

Really? Do meteors over Alabama have a usual geographic direction?

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