[meteorite-list] Request for assistance

From: Matson, Rob D. <ROBERT.D.MATSON_at_meteoritecentral.com>
Date: Tue, 5 Jul 2016 20:25:54 +0000
Message-ID: <4A4FA25E4DFE584AA580F4F069F9B440B5F56379_at_EMP-EXMR104.corp.leidos.com>

Hi Marc,

Here are the time-stamps I've got for these, and the prospects for refining some of them:

Indian Butte - 7 June 1998, ~8:58 pm MST (3:58 UT on 8 June 1998); Robert Ward might have a more
accurate time. This time is based on a single California witness. I'm unaware of any time-calibrated
records of the event, but the fall was definitely prior to 4:00 UT.

Elbert - 11 January 1998, ~00:09 am MST (7:09 UT). Again, no good instrumented record of the
exact time of the fall or start of dark flight.

Osceola - 24 January 2016, ~10:25:10 am EST (~15:25:10 UT). This estimate is probably good to +/-
10 seconds. It's based on a combination of sonic boom time delay and an iPhone 6S picture
of the dust trail snapped at 10:25:37 am at least 15 seconds after the fireball.

Cartersville - 1 March 2009, ~22:50 EST (~3:50 UT on 2 March). I'm not aware of any videos of
this event; it might be worth trying to find archive seismograph data for this fall to help
constrain the event time. ET.SWET was active at the time of the fall.

Battle Mountain - 21 August 2012 ~23:17 PDT (~6:17 UT on 22 August). Should be able to refine
this further using the sonic boom signature from LB.BMN at 6:18:17 UT in conjunction with a
radiosonde temperature profile for the area at the time of the fall.

Kitchener - 12 July 1998 ~8:30 am EDT (~12:30 UT). As you know, Buffalo radar got a big hit
sometime around 12:38 UT. I originally looked at this one back in 2010 and revisited it again
in 2014. We'll probably never have good timing information on this one.

Ash Creek - 15 February 2009 ~10:58 am CST (~16:58 UT). This is another one that I've been
meaning to revisit seismographs for in the hopes of improving the fall time estimate.

Monahans - 22 March 1998 ~18:37 CST (~00:37 UT on 23 March). Estimate is based entirely
on KMAF radar. Probably hopeless to get an accurate time for this fall.

Lorton - 18 January 2010 ~17:38 EST (~22:37 UT). Time is an estimate from witness statements
and the earliest radar hit from KLWX. Another one that might benefit from a search for
seismic data.

Mifflin - 14 April 2010 22:06 CDT (3:06 UT 15 April). Since the earliest radar return on this one
is at the somewhat unprecedented altitude of nearly 30 km, I would use the precise time
of this scan plus maybe a couple seconds to signal the start of dark flight. For confirmation
of the time, I could use the US.JFWS seismograph which recorded the sonic boom at
3:07:35 UT.

--Rob
Received on Tue 05 Jul 2016 04:25:54 PM PDT