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(meteorobs) Meteor Activity Outlook for October 20-26, 2000



The moon is at last quarter on Friday October 20 and in the sky during
the last half of the night. It is rapidly waning meaning that it is
becoming less of a nuisance. The evening hours are totally free of
moonlight but unfortunately the lowest rates persist before midnight.
Despite the moonlight I would suggest saving your efforts for the second
half of the night and enjoy the Orionids and other active showers
visible before dawn. The positions listed below are exact for Saturday
night/Sunday morning October 21/22. The positions do not change greatly
day to day so these positions may be used during this entire period. 

This week the Antihelion radiant is centered at 02:56 (044) +16. This
position lies in a rather blank area of eastern Aries some 10 degrees
southeast of the Pleiades. If you are also familiar with the
constellation of Cetus then the radiant lies just north of the "tail" of
the whale. As always, the antihelion radiant rises shortly after sunset
and is in its best position due south near 0200 local daylight time.
This will shift an hour earlier as we adjust to local standard time 
next week here in the USA. Rates should be decent from this area
especially near 0200 LDT when perhaps as many as 5 meteors per hour may
appear from this source. These meteors will all appear slow no matter
where they appear in the sky. For those who report to the IMO the
meteors from northeastern Aries and northwestern Taurus should be 
labeled North Taurids (NTA) and those meteors from southwestern Taurus,
southeastern Aries, and northeastern Cetus should be labeled South
Taurids (STA).

The Orionids are predicted to reach maximum activity on Saturday morning
October 21. Rather than possessing a sharp peak the Orionids can put on
a good display anytime during the period October 20 to 25. The radiant
position lies at 06:24 (096) +16 which is on the Orion-Gemini border
just a few degrees west of the bright 2nd magnitude star Alhena (Gamma
Geminorum). The radiant is not sharp and there have been suggestions
that subradiants are active nearby. The radiant rises near 2300 LDT
(11pm) but is best seen during the last few hours before dawn when it
lies high in the southern sky as seen from northern latitudes. Since
this shower is rich in faint meteors the nearby moon, which will lie on
the Cancer/Leo border on the 21st, will most likely reduce the number of
shower members seen. Under these conditions perhaps 10-15 Orionids will
be seen per hour late in the morning from rural sites. The Orionids are
normally swift meteors but those seen near the radiant or near the
horizon will appear to travel more slowly.

The Epsilon Geminid radiant lies a bit further east and north of the
Orionids at 07:04 (106) +27. This is somewhat close to a position
between the Orionid and Northern Apex radiant so care must be take with
shower associations. Being further east it will be more influenced by
moonlight reducing the hourly rates to perhaps 1.  Like the Orionids 
the Epsilon Geminids are also swift and best seen just before dawn.

The Northern Apex is now located at 07:56 (119) +35. This position lies
in extreme southwestern Lynx, northeast of the bright stars Castor and
Pollux. Since this radiant is diffuse any meteors from the southern half
of Lynx, northeastern Gemini, or northern Cancer would be a good
candidate. As seen from the Northern Hemisphere this source should still
be quite active producing 3-4 meteors per hour near dawn. From the
Southern Hemisphere this source would be much lower in the sky and only
producing 1-2 meteors per hour. 

The Southern Apex source lies exactly 30 degrees south of its northern
counterpart at 07:56 (119) +05. This position lies in eastern Canis
Minor 5 degrees east of the brilliant star Procyon. Any swift meteor
from Canis Minor, southeastern Gemini, southwestern Cancer, or
southwestern Hydra has a good chance of being from this source. As seen
from the Northern Hemisphere this source should produce 2-3 meteors per
hour near dawn. Similar rates would be seen from the Southern
Hemisphere. 

The Leo Minorids are listed among the radiants of the Dutch Meteor
Society (DMS). The activity period is only 3 days long centered on
October 24. The radiant is reported to be at 10:48 (162) +37 on October
24. This area of the sky lies in extreme eastern Leo Minor near the
border with Ursa Major. The moon will be in this same general area of 
the sky during this activity period but it will be quite thin and thus
not too much of a nuisance. Any shower members would be slow moving near
the radiant and the horizon but swift if seen high in the sky and far
from the radiant. The listed ZHR is only 2 so activity will be scarce.
Observers with video and camera equipment and those visual observers who
plot are urged to keep a lookout for any possible activity from this
radiant.

The Sporadic rates for the Northern Hemisphere are just past their
annual maximum. With slight interference from the waning crescent moon
one would expect perhaps 8-10 random meteors per hour during the last
hours before dawn. During the dark evening hours perhaps 5 random
meteors can be seen per hour. Rates seen from the Southern Hemisphere
would be roughly 50-75% of the northern rates.
  
Clear Skies!
Robert Lunsford
AMS Visual Program Coordinator
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