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(meteorobs) Hot Meteors

Here's a post of mine from 24 March, 2000 that seems to have relevance 
to our discussion today, except I was pretty much alone then believing in 
hot meteors, seems they are becoming a little popular now.

Dave English wrote:
> 
> I would like to add to this discussion again. I have always mantained that
> there had been several hot and glowing meteorites discovered by persons
> right on site, or people nearly hit by meteorites. So I did some research
> and studied the possibilities and looked up heat transfer (it isn't real fast),
> melting and vaporizing points for iron and nickle, and like our worthy
> scientists, guessed at the possibilities with the information at hand. Here
> are my conclusions that weakened my previous position:
>                           1.  Meteorites are preheated by:
>                                    a.  solar radiation
>                                    b.  preignition flight in the upper atmosphere
>                           2.  Stony meteorites most likely never arrive hot
>                           3.  Of the 10% of meteorites that are metal, few will be of
> the size to retain heat during free flight
>                            4.  Only a small percentage of iron meteorites may arrive
> hot and glowing because of size, too small and cools during free flight, too
> large to absorb heat to the core of the meteorite
>                             5.  Only a few iron/nickle meteorites of the right size
> will fall to Earth at the appropriate angle (steep or a long burning flight)
> to land with heat energy radiating from the core, possibly to low red heat
> as was reported in 1885 when a person was almost hit by a meteorite.  It
> had left a trail in the sky to his corral area where he was feeding horses.
> He said it looked red like a lit cigerrette and was glowing down in a 12 inch
> hole. He dug it out the next morning after it cooled (I posted the report last
> year).
>                            6.  Meteorites that produce sonic booms will more likely
> hit with some heat as they may be moving very fast while in the lower
> atmosphere that can carry sound
> 
>      I predict that if someone would use heat sensitive cameras and regular
> cameras to capture meteors at the same time, that the heat sensitive
> cameras will show a trail before and after the visible light camera. Here's
> a project for someone.
> 
>      A word on a word. I used preignition flight because that generates a good
> visual image of the meteor flying towards the thicker atmosphere, heating
> up but not yet glowing with heat and visible to us watching the skies. I
> know that they must heat up first because some very speedy meteors ignite
> much higher than others, 10 km or more (20?) this has been reported
> here. Also a member at SeeSat reported a satellite that was observed while
> it was in the shadow of the Earth, glowing red from the friction but
> surviving for another orbit or two. My point is that meteors and
> meteorites arrive warm by the sun and by flying through the outer
> atmosphere before it becomes dense enough to cause visible radiation.
>       My conclusion is that hot meteorites occure less frequently than I had
> thought. Their size, angle of fall, amount of time in the preignition zone,
> all limit the number of glowing meteorites striking Earth.
>                                                                   Dave English

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