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more meteor notes

      It's time for another jumble of notes.  First, I haven't been lucky
enough to hear a meteor in 36 years.  But Povenmire has heard several.  In
the 1972-73 period we both saw 2 major fireballs.  In each case Povenmire
was nearly under them while I was 70 or so miles to the NW.  He got loud
booms and I got nothing.
     Jeff Wood's group colors were in their organization's publication with
no further details given besides what I noted previously.
     I dump cirrus-laden hours.  There is enough good data already so I
don't need to salvage bad hours.  Someone who lives in a cloudy climate
would have need to use whatever he can get.  If a batch of cirrus comes
tromping in, that is the perfect time for a refreshing nap.
     In 1976 I simplified my data recording.  Eliminated were distance (path
length in degrees), duration of meteor, and time for every meteor seen.
Times noted are beginning and ending of session, any breaks, any change in
cloud conditions, and passage of minute 26 of each hour.  I still use the
AMS system of observing for exact and complete local hours determined by
longitude.  This insures accurate hour-by-hour diurnal changes in meteor
rates as well as accurate comparisons of results in different years.  I am
accumulating data in my personal rate catalog which has uniform conditions
throughout the year to minimize uncertainties.  Same local hours + same eyes
+ same skies = reliable and reproducible rates.  Longitude here is 81 1/2 W
which is 26 minutes in time west of my standard meridian of 75W.
     Time of each meteor of -3m or brighter is noted; I find no need to do
the others, even during most major maxes.  The 1985 Perseids might have been
useful to get all times: we definitely had some strangeness in that one with
intense activity for 15 minutes followed by zero activity the next 15
minutes, several cycles of that completed.  (A potential 100+/hr shower was
cut in half by the bizarre blank periods.  That was 4 years after the great
1981 shower I saw at 100/hr, hence, my turn was again at hand but it didn't
follow through.)  Conclusion: I seldom need the time cube.  It was on hand
for the possible Monocerotid shower last November.
     I agree with George that color in meteors fainter than +2m is not
useful.  We could say my +2m's may not be useful since that is the level at
which I start losing color.
     Also for George on the 1972 early-evening Quadrantid: don't forget that
the radiant has to set sometime!  I was west of Orlando, lat 28N.  The
radiant rises down here around 1 AM, but it sets sometime around sunset.
Its high Dec, +50, would keep it up much longer than it is down.  The
direction coming from (NW), path length, and apparent speed all made this
meteor an unmistakable Quad.  Sunset is about 540 PM and full darkness by 7
PM.  I find evening-twilight meteors are quite rare; over the years I
haven't seen more than a couple dozen of them.  The Geminid max doesn't help
out any, for the radiant doesn't rise until 7:30 PM here.  I did see a 1972
Perseid go 90 degrees in evening twilight, that radiant rises shortly after
dark so there is another case of a radiant-below-horizon meteor.  For Lew, I
don't really know how far down a radiant can be to still produce a meteor.
I haven't seen enough of them to get any idea; 5 degrees is no problem, 10
might be stretching it.  Ruck must be with you to see one at all, as the
Chinese would say.
     Kkreigh is right about some coloring being noticeable in both Dipper's
bowl stars.  Kochab in the Little one is definitely orange to me.  In the
Big, the northern Pointer looks yellow in contrast with its partner.  The 3m
star 2 degrees NW of Altair is strongly orange; I noticed it casually for
the first time right after Hurricane Donna in blackout conditions over Miami
(1960).
     Later on I will have to give a complete color chart on some major
shower.  Bob L has produced similar ones.
     Hopefully most of my musings are understandable to beginning observers.
I tend to be non-technical and like to describe what I am actually seeing.
Giving corrected rates only can be very misleading; I was soundly fooled by
some of these in my early days.  Besides, I want to know what other people
are actually seeing.  The latest problem is the 1995 Eta Aquarid ZHR 100+
from South America--what are they basing that on??  I saw only 9/hr here for
3 straight mornings, sky 6.5, radiant 30 degrees up at dawn.  There is an
advantage from deep southern sites but it is definitely not a vast advantage.
     Until next time,  Norman