(meteorobs) 2012/02/01 TX Fireball Trajectory Solutions v1

Jake S jakeschaeferml at gmail.com
Wed Feb 8 22:33:55 EST 2012 

I've made some revisions as well. With the altitude data from Bill
Cooke. Given that it was so shallow and still at 60 km when it passed
by the seismograph greatly alters what I had expected. I would have
expected the sonic boom to not generate such a large pressure wave
until in the more dense lower air. But anyways this high altitude
brings the trajectory farther south. Based on my calculations from the
seismograph, the trajectory Bill Cooke has provided is only about 3km
off which is easily within the uncertainty in my calculations
(especially if the speed of sound is slightly off, colder than a
standard day?)

http://3dradar.wordpress.com/2012/02/09/dfw-tx-222012-0157-utc/
-jake

On Wed, Feb 8, 2012 at 7:09 PM, Mike Hankey <mike.hankey at gmail.com> wrote:
> Jake,
>
> Thanks for the input. I'm going to make some revisions to my
> information and also take into consideration the 2nd camera in Hawley.
> Prior to Bill's post I was really confused about the cameras in
> coleman vs hawley. I didn't realize there were actually two cameras.
> I'm also going to work in the data from Pat on the austin camera. i
> also have some revised & new az/el values. I will report back with v2.
>
> Thanks,
>
> Mike
>
> On Wed, Feb 8, 2012 at 8:55 PM, Jake S <jakeschaeferml at gmail.com> wrote:
>> I drew up a rough map with the seismograph data on it (very rough
>> drawing, if you want the actual data I can probably send you it).  In
>> my previous post i had said the video trajectory was too far north but
>> I think i must have drawn it off or something, because it appears they
>> are very close. The video trajectory is actually slightly south.
>>
>> http://3dradar.wordpress.com/2012/02/09/dfw-tx-222012-0157-utc/
>>
>> I know all the eye witness's seem to show it over by Edgewood but i
>> think these two pieces (video and seismographs) show it further north,
>> the one seismograph isn't the greatest of hits but if going off that
>> as being accurate, I'd search up by Greenville, TX, otherwise it could
>> rotate more East/West and be down near Edgewood also but i think this
>> is the less likely scenario. Until they are found, we won't know...
>>
>> -Jake
>>
>>
>> On Wed, Feb 8, 2012 at 9:48 AM, Pat <pat_branch at yahoo.com> wrote:
>>> Jake can you provide a line (or the coordinates for a line) that represent the center of the seismograph data? I think between that and the Austin video I can actually look on the ground.
>>>
>>> I currently have it following the dark green band in Mike's map4 below, but displaced to the north so that it just clips the north of the cedar creek reservoir. I think the seismograph data could give us a directional line on the ground (and if I am correct it should pass thru Ennis).
>>>
>>> --- In meteorobs at yahoogroups.com, Jake S <jakeschaeferml at ...> wrote:
>>>>
>>>> I have a few comments on your trajectory, particularly on this image:
>>>> http://www.mikesastrophotos.com/wp-content/uploads/2012/02/map4.jpg
>>>>
>>>> I think your red/maroon colored trajectory is too far north. Based on
>>>> sonic boom arrival times to seismographs, the trajectory looks like it
>>>> will be between the dark green and red lines on that map.
>>>>
>>>> >From the coordinates of : (31.99,-97.46), the meteor HAS to have
>>>> passed no more than 86 km distance at its closest point. Factoring in
>>>> altitude it must travel will reduce this further 86 =
>>>> sqrt(altitude^2+ground distance^2). Factoring in a reasonable mach
>>>> angle for the shockwave only slightly increases the distance. With all
>>>> this in mind, i think your red trajectory is possibly up to 20 km too
>>>> far north, at least near the starting point of that line, what that
>>>> shift will do to the endpoint i don't know. If i knew the velocity and
>>>> altitudes of the trajectory this could be refined i think.
>>>>
>>>>
>>>> On Tue, Feb 7, 2012 at 7:52 PM, Mike Hankey <mike.hankey at ...> wrote:
>>>> > Thanks Pat. I would agree with a SE of Greenville location. Are you
>>>> > saying these guys found meteorites from this fireball already?
>>>> >
>>>> > On Tue, Feb 7, 2012 at 10:29 PM, Pat <pat_branch at ...> wrote:
>>>> >> Mike,
>>>> >> Here is a great meteor view which I have not seen until now. It was shot in Austin from the Joe's Crab Shack at 600 Riverside Dr. The angles should be easy to calculate accurately because the city skyline gives you some angle estimates. I posted a picture of exactly where the video was shot from in the Files section of this group.
>>>> >> The view was shot NNW between the two trees just off the balcony.
>>>> >> http://www.youtube.com/watch?v=8juQ_ld_G7U
>>>> >>
>>>> >> I still think it was SE of Greenville, but I am sure there were at least two large pieces that separated early. I have seen pictures of a team from the Austin Planetarium which I believe found some meteorites about 1 mile east of Edgewood TX at the corner of County Roads 3601 and 3604.
>>>> >> Pat
>>>> >>
>>>> >> --- In meteorobs at yahoogroups.com, Mike Hankey <mike.hankey@> wrote:
>>>> >>>
>>>> >>> Hello,
>>>> >>>
>>>> >>> I've been working on the trajectory for this fireball, but i've been a
>>>> >>> little discombobulated due to the mystery over Kevin's Hawley /
>>>> >>> Coleman camera location. A friend forward'd me what I believe to be
>>>> >>> the best location for Kevins camera and we suspect it is in coleman
>>>> >>> and not hawley.
>>>> >>>
>>>> >>> I am a lot happier with these solutions and want to share now that I'm
>>>> >>> more confident.
>>>> >>>
>>>> >>> I want to stress this is still just a v1 cut at the trajectories and
>>>> >>> the calculations are based on manual solving of the allsky images,
>>>> >>> which is an imperfect art form. So, this is probably wrong, but the
>>>> >>> best calculated guess with available information.
>>>> >>>
>>>> >>> I'm willing to share my values and KMZ with anyone who is interested
>>>> >>> and I would actually like to compare notes with someone to make sure I
>>>> >>> didn't make any major mis-calculations with regard to lat/long/az/el
>>>> >>> values.
>>>> >>>
>>>> >>> I will continue to work on this folding in good witness data.
>>>> >>>
>>>> >>> Here are the maps:
>>>> >>>
>>>> >>> http://www.mikesastrophotos.com/comets/2012-02-01-texas-fireball-trajectory-solutions/
>>>> >>>
>>>> >>> Thanks,
>>>> >>>
>>>> >>> Mike Hankey
>>>> >>> Freeland MD
>>>> >>> _______________________________________________
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>>>> >>> meteorobs@
>>>> >>> http://lists.meteorobs.org/mailman/listinfo/meteorobs
>>>> >>>
>>>> >>
>>>> >>
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