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(meteorobs) Re: Geminid observing history
Lew writes:
>This one hour of active counting was max night, in a high ice haze or CS
>cover, so that moonlight wrought havoc with my LM - most of my star counts
>had to be at Zenith, and I only made mid 4.0s on average... IMO report to
>follow.
>
>No wonder the mighty Geminids are historically so widely underrated by
>writers from Northern climes!
>Anyway, for '98 I plan on being somewhere
>SOUTH in mid-December...
Not a bad idea. Robert Hays near Chicago has never seen the Geminids rival
the Perseids, using his words. He has been a consistent observer almost as
long as I have. He usually takes a couple of days off around Perseid max,
leaves town, and sees a decent show in August. But he has never seen the
Geminids under similar good conditions. It must be difficult to travel in
December around that territory.
S&T did not update their calendar mentions of the Geminids until my
correspondence with them in the early 80's. They were using the outdated
value of 50/hour until then.
The Geminids have strengthened considerably just in my years of observing,
and they have only been around since the middle of the previous century. In
the late 60's Olivier mentioned in one AMS Annual Report that the Geminids
in current years now rival the Perseids, improving from inferior status
earlier this century. Since then the Geminids have become vastly superior,
excluding brief well-timed Perseid returns that seem to last only an hour.
1963 was the first year I saw the Geminids without the moon on max night.
From Miami with LM5.5 I had Geminid rates of 25 to 30/hour. Converting to
what I would have seen in sky LM7.0 makes it around 50 to 60/hour. My
correction factor from 5.5 to 7.0 is right about a double, or 2. By 1972,
the first year that I didn't plot during the Geminids, I saw 70/hour in 7.0
sky. Ten years after that I was seeing over 80/hour regularly, and there it
remains today. We are supposed to be moving through the best Geminid years
in the present generation; if that is so, my hope to see continued
strengthening to 100/hour probably won't happen.
As far as a time for the Geminid max is concerned, I find it is a flat max
lasting for a full day. There is no discernible sharp peak. Every dark
year I see almost the same peak rates on Dec 13/14, except one day earlier
in leap years.
Dec 16/17 is a clear night at last, but with the bright moon I'm going to
skip observing until Ursid max. The planet show continues interesting, and
Joan is excited at really seeing their movements for the first time. Every
clear day I have been finding Venus in daylight easily.
Norman