[meteorite-list] Fireball report from this morning in Utah

From: Chris Peterson <clp_at_meteoritecentral.com>
Date: Thu, 7 Dec 2006 09:27:57 -0700
Message-ID: <085c01c71a1c$aad23da0$2721500a_at_bellatrix>

Ed-

Reentering objects are responsible for only a tiny fraction of
fireballs- well under 1% based on my empirical data. I think Marco has
looked at this, too... he might have better numbers. In any case, while
you certainly might have seen space junk, natural meteors are much more
likely.

There seems to be a strong correlation between color and speed, with
slow objects being seen as bright green, and faster objects seen as pale
green or white. I expect that is simply because the faster objects are
hotter, and the "white" blackbody output is swamping the fainter oxygen
emission. Reentering space junk is slow, and is usually reported as
green.

Chris

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


----- Original Message -----
From: "E.P. Grondine" <epgrondine at yahoo.com>
To: <meteorite-list at meteoritecentral.com>
Sent: Thursday, December 07, 2006 9:00 AM
Subject: Re: [meteorite-list] Fireball report from this morning in Utah


> HI Chris -
> --- Chris Peterson <clp at alumni.caltech.edu> wrote:
>
>> most of the rest see some variation of
>> green, ranging from pale lime to bluish. This is
>> probably caused by the 558 nm "forbidden"
>> oxygen emission line, mixed to varying degrees with
>> a white thermal emission.
>
> What is this? I remember that the first of the two
> fireballs which I have seen was so green I thought it
> was a re-entering war-head.
>
> Ed
Received on Thu 07 Dec 2006 11:27:57 AM PST