(meteorobs) Breaking News - Major TX, OK, AR, MO, KS, CO, , NE Green, Fireball Meteor ~9:21CDT 23MAR2011

Robert Lunsford lunro.imo.usa at cox.net
Sat Mar 26 17:09:19 EDT 2011


Esko,

Your reports and analysis are most welcome and appreciated! I know I speak for a majority of our readers in stating that we 
appreciate the time and effort you spend in sharing your thoughts and data with us. I find your posts fascinating and most 
informative.

We all look forward to your contributions!

Bob

-----Original Message----- 
From: Esko Lyytinen
Sent: Saturday, March 26, 2011 1:09 PM
To: meteorobs at meteorobs.org
Subject: Re: (meteorobs) Breaking News - Major TX, OK, AR, MO, KS, CO, , NE Green, Fireball Meteor ~9:21CDT 23MAR2011


Hi,

I could find seven stars in the Oklahoma city camera sum image and ( to
some degree with the help of earlier Sentinel camera derived imaging
geometries) could calibrate this quit well.

I give here the start and end directions for also others to use, if of
any use.
start az=292.60 , alt=24.305
end   az=262.07, alt=30.14
(with too many decimals)
I do not even have exact coordinates of this observatory, so for example
an error of 11 kilometers in its location causes an 0.1 degree error in
the star-postitions. But considering the image size, the real accuracy
may not be much affected.

With these directions I went trough the previuos calculations, now with
even more exact calculations and with the same expected start and end
heights and assumed deceleration, I get the entry velocity as 15.5 km/s.
With these assumptions It comes from directions 304.7 and slope 20.0
degrees ( reference horizon and meridian is 35.0 N, 98.0 W ).
I have from the calculating Excel sheet automatic links to (somewhat
modified) Marco Langbroek's Excel sheet for solar system orbit and I
give here what it gives.
The apparent radiant RA   26.3 , dec +39.3
geocentric radiant      RA 12.4 , dec +30.7 .
heliocentric orbit:
a=1.66,
e=0.478
q=0.867
peri=126.7
node=2.944
( peri+node=129.65 )
i=7.67

If the end height would be 5 kilometers higher, this would decrease the
entry velocity by about 1 km/s and shift the radiant on the sky by about
3.4 degrees and of course the solar system orbit would have some change.

I might be thinking of possibly measuring some individual frames, but
this I would like to do from the original size video, that I do not have.

But just an hour ago at 18:43:04 UT we had our own quite fine fireball
:) At first impression this looks "smaller" but might have dropped a
small meteorite, also this ? Now the study of this gets higher priority
here, at least for a while.
Hope, I did not make any typos, in the values.

Esko





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