 |
| (click on image to enlarge) GIF Photo Credit- Armagh Observatory, UK Apostolos Christou and James Finnegan http://star.arm.ac.uk/movies/2012/AllSky/ |
http://star.arm.ac.uk/movies/2012/AllSky/
`AllSky` observation from N. Ireland, 7 hour animation. Time GMT.
Especially of interest are Frames 306 to frame 330.
After the `fireball` in Orion at frame 306 the continuation and dispersal of material is clearly visible in the animation for about 15 to 20 minutes.
I have still to fully analyse and assess our simultaneous ELF recording and spectrogram for the minute corresponding to frame 306. I am waiting for other visual and radio scatter reports to better pin down an exact time for the fireball/fragmentation phase.
(Although there is one `ELF event` which has a following brief bursting `hail on a tin roof effect` just like a Sprite but much shorter in duration! Explosive distribution of material after the end flare but before long term dispersal and `disturbance` at that altitude?)
At the moment we only have one other (unconfirmed) video observation of this `fireball` (from Bayfordbury `AllSky`) a site 500 km South East of us near London, so the following estimation of its position and altitude is approximate...
"I think that the Bayfordbury frame capture that I showed you is also our `fireball`. Its observed position appears to correspond.
Using the AMS meteor meniscus graph, some basic equations and geometry and knowing the RA and DEC of the relevant nearby stars (to enable `fireball` azimuth and elevation estimation at the time of observation) my initial estimate puts the observed bolide location at approximately Galway/ North Co Clare area.
That is ~250 km from us and ~800 km from Bayfordbury if at ~80-100 km altitude.
I estimate that the ablated material, seen continuing to travel and expand and subject to dispersion, would continue for several hundred km further across the Eastern Atlantic west of Mayo".
Regards,
James Finnegan.
Armagh Observatory.
Thank you James & Apostolos!
2012 THE Year of Meteors!
