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(meteorobs) Re: Stale pubs + Gem max + more
I have never seen a distinct peak for the Geminids. Every dark year I get
very similar max rates. So everyone has one night guaranteed to be very
good, and a second night good as well.
The coldest I have done observing in was the night of bright Geminids Dec
13/14 in 1968, northern Mississippi. In late evening it was 25oF with wind
25 knots. I lasted 45 minutes before having to can it. Went back to the
dorm to warm up, then did a little casual watching out front.
It is possible to get hypothermia in Florida with temps in the 50's. Old
people can have defective internal rheostats, so they can get dangerously
cold and not know what is happening. Several of them die from this each
winter season. Some people have no internal house heating. When it
becomes needed, a very stupid way to get heat is bringing in a charcoal
grill or gas lantern. That might be your last night alive due to carbon
monoxide accumulation. Hyperthermia comes from desert winds above body
temperature; the faster it blows, the hotter you get.
Old books established a good baseline for many of the major showers as to
max rates, and some of these have not changed today. An occasional year
might vary but the observed max rate for Lyrids 15, Orionids 25, Leonids in
ordinary years 10-15 quoted many years ago agree perfectly with what I see
even now. Hence, I have normal perception. (Lyrids were very poor after
1982 until recently; storm years seem to upset the status quo for years
afterwards. That is now in progress with the Perseids.) Perseids listed
at 50 I generally did not reach (just 40). But Geminids until 1980 quoted
at 50, while accurate for earlier this century, needed adjustment. S & T
kept using this number until I recommended raising it to 75. Today I would
call the Geminids 80, running constant after 1985 at that level. All of
these showers except the Perseids I get a chance to see with their radiants
nearly overhead in a good sky, so no corrections are necessary. True,
including the Draconids, Andromedids, etc. in the list of major showers
represents ignorance and laziness on the part of new book writers just
copying the old list.
With the baselines from above in mind, I have a very serious problem with
the establishment of Bob Lundsford as a "normal" observer. That, he is most
definitely not ! I have been with a good many observers over the years, and
the vast majority of them were within 0.8 to 1.3X my perception. I have
been aware that many more higher perceptions have emerged starting with a
couple in the late 60's, then in ever increasing numbers in the 70's and
80's. What the dickens is going on?? I encounter one occasionally, but not
nearly often enough to consider my perception to be below average. If you
see more, your interest is naturally stimulated so you will observe more
than someone with low perception. These will also be the ones you hear
from. Apparently very few normal observers are in the IMO today, and the
strong bias toward high perceptions just blares out. This looks like the
reason all the ZHR's are coming up twice what I think they should be.
Perception should not necessarily change with age or experience, as long as
eyes stay good. I have the same perception now as 30 years ago. You are
born with it. I have witnessed a couple of people come out for their first
observing session and end up seeing double my rates, but these are uncommon..
On the discussion about ZHR's, the news here is unfortunately not good. I
have problems with every point, and will get out some hard numbers to
illustrate these another time.
Norman