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Re: When it's a rock! (was,"RE: When Does a Meteorite become a Meteorite?")

In a message dated 99-09-12 21:13:08 EDT, you write:

michael<< 
 The liturature, AS A WHOLE  has ALWAYS been consistant: A metoeroid
 prior to hitting the earth (even when it is producing light passing
 through the atmosphere, even when it is in its "dark phase" etc.) and
 the light phenomenon is a meteor. When it arrives on earth, it is a
 meteorite - until then, it is a meteoroid. <<

The consistent definitions I see in various literature indicates that a 
meteoroid is a particle in "extra terrestrial space" and or/ in another solar 
orbit other than that of earth's. The key words to me are "space" and 
something to indicate not attached to earth, such as in the form of "extra 
terrestrial" or "another solar orbit" etc.  Once the object violates any of 
it's given definition, I can't see how it can be referred to as being the 
same as it was before. Something different has happened to the meteoroid 
after the end of it's meteor phase and at the beginning of the dark phase 
that entitles it to be called something else other than what it was prior to 
these changes. The object is no longer being described by any of it's 
previous consistent definitions. It's no longer in "space"...yet alone "extra 
terrestrial". It is in an atmosphere belonging to the earth. This is not 
"outside earth", but within. This is not "space" nor is it anymore "extra 
terrestrial".   It is under the total influence of the earth. No longer an 
independent object in relation to the earth. It no longer is in a solar orbit 
separate of that of the earth's. 

michael>>Yes, I KNOW an isolated
 comment here and there in the liturature has left room (just a teeny
 crack) through which all of this questioning of terms has squeezed.<<

An isolated comment here and there has left room? :o)  What in a meteoroids 
definition now describes the object we have during the dark phase? The best I 
can come up with in just about any meteoroid definition is "a solid particle 
or body of small dimensions". This would now qualify just about any grain of 
sand on the beach or rock in a gravel pit. This would hardly be acceptable. I 
see no other choice than to refer to the object in dark phase to that which 
it most resembles....and in some references outright call it as....a 
meteorite. 

 michael>>  I am confused. The terms have always been clear and consisatant - 
there
 IS NO DARK PHASE - any more than there is a "PRE LIGHT PHASE." 
 Asteroid >><<

An asteroid is the "pre light phase" if you will, for a branch of the larger 
parents of the  meteoroids. If an object is large enough when it enters the 
earth's atmosphere, it won't have a dark phase since the atmosphere wouldn't 
be able to slow it down enough to continue as one.  An example was the 1972 
great fireball over Wyoming. It entered the atmosphere, but it never stopped 
glowing as it passed thru during the graze. It's still out there roaming 
around out in space with an orbit independent of the earth's. Since it's 
speed was never slowed down enough to come under the earths total control, it 
didn't enter a dark phase. There is not a problem with calling it a small 
asteroid or even a large meteoroid still if you wish. I think the problem 
with what seems to have always "been clear and consistent terms" in the past, 
is that nearly everyone has gotten comfortable in applying these terms 
improperly all this while. 
GeoZay

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