Hi All,

I thought I'd check the Global Seismic Network to see if the sonic
boom of the entry of 2008 TC3 was recorded on infrasound. The four
closest stations in Africa have codes BGCA, KDWA, FURI and RAYN:

http://aslwww.cr.usgs.gov/Stations/gsn_map.gif

I was only able to find online telemetry data for FURI which is the
Mt. Furi, Ethiopia station. FURI's station information is:

http://www.fdsn.org/station_book/IU/FURI/furi.html

Specifically, they are located at 8.903N, 38.6883E, altitude 2545m.
This is about 1430 km away from 20.6N, 33.1E -- a rather long
distance to have much hope of recording a bolide sonic boom. But
just in case, I estimated what the approximate time delay should
be. Assuming a speed of sound of 331 m/sec (the velocity in dry
air at 0 C), the time to cover 1430 km would be 1 hour 12 minutes.
The actual arrival time could vary quite a bit from this since
the sound path is very non-linear. 1 hour 12 minutes after
atmospheric impact at ~2:45:30 would be 3:57:30 UT. Well, take
a look at the trace:

http://aslwww.cr.usgs.gov/Seismic_Data/telemetry_data/FURI_24hr.html

Could that squiggle at 3:51 be it? It's a bit early (meaning
the speed of sound would have to be higher, or the impact location
closer), but it seems a bit coincidental that the only signature
on the trace for the last 24 hours that looks anything like a sonic
boom occurred within 6 minutes of the expected time.

--Rob