[meteorite-list] Impact Duration Time

[Robert Woolard]

Hello List,

  Would any members be able to help with a question I
have regarding the "impact-duration-time" (???) of
some typical falls? I don't know if that's the best
terminology to use, but what I mean is: What would be
a "typical" measure of time between the impact of the
FIRST (known) individual at the start of the
strewnfield, and the fall of the LAST (known)
individual? I can't remember ever having read of any
instances where these times were actually determined.
I know the odds for accurate recordings of both of
these times would be very slim, but does anyone know
IF they have ever been recorded for a fall(s)? 

  Also, is it a relatively simple matter of getting a
VERY rough ESTIMATE of the spread of time by simply
dividing the length of the strewnfield by a max free
fall speed of ~ 200mph???  I know that the angle of
entry, the wind speed, the density of the meteorite,
etc., would all affect the results, and the answer
from such a simple equation would truly give ONLY an
estimate if I'm right. But WOULD this give an
approximate duration time??  For instance, if a
strewnfield is ~ 7 miles long, would it be fairly
accurate to say that meteorites were impacting over
about a 2 minute spread of time during the fall? And
if the strewnfield was ~20 miles long, impacts may
have occurred over ~ 6 minutes?

(7 miles/200mph = 0.035 hours,or = ~2.1 minutes)     

(20 miles/200mph =0.1 hours, or = ~ 6 minutes)


   Finally, IF all the above is even halfway accurate,
could one safely say that during a "typical" fall,
meteorites are impacting down the length of the
strewnfield for approximately 1 to 5 minutes? Or am I
way off base?  If this is right, I never thought about
the concept of meteorites hitting the ground for 5
solid minutes (or more!) during a fall. That puts
thing in a different perspective, to me at least. 

  Thanks,
  Robert Woolard









      ____________________________________________________________________________________
Never miss a thing.  Make Yahoo your home page. 
http://www.yahoo.com/r/hs