[meteorite-list] (meteorobs) Geminid photos uploaded/did anyone notice anything unusual ab...

From: geozay at aol.com <geozay_at_meteoritecentral.com>
Date: Fri, 18 Dec 2009 12:05:11 EST
Message-ID: <adb1.201c8f2b.385d1047_at_aol.com>

>>Perhaps it's just me, but did anyone else notice more persistent trains
than usual? Although there were not too many fireballs that I saw, even
dimmer (but still negative magnitude) Geminids seemed to leave long
lasting trains.<<

This is something I wouldn't be expecting. I kept personal records of
train activity when I observed in the 1990's. For the Geminids, I showed a rate
of only 3.2% that displayed visible wakes or trains. That was for the
years of 1993, 1995, 1996 and 1998 under sky limiting magnitudes of between 5.6
and 6.0. Those years produced 1413 Geminids with 45 showing trains. I'd
frequently see many bright members without a train. The Geminids entry
velocity is 35 km/s. I noticed that the faster the entry velocity, generally the
more trains will be perceived. For example Leonids have an entry velocity
of 71 km/s with 55% train production. And for North Taurids with entry
velocity of 29 km/s I saw a rate of 1.6% train production. On occasions I'd find
something that doesn't hold to that pattern...such as the Alpha
Capricornids...with an entry velocity of 25 km/s I find their train production around
3.9%. As for the sporadic population I found overall train production to
be at 13.8%
George Zay
Received on Fri 18 Dec 2009 12:05:11 PM PST