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(meteorobs) Meteor Activity Outlook for January 28-February 3, 2000

The moon has just passed its last quarter phase leaving the evening sky
totally free of moonlight this weekend and beyond. The situation also
improves each day for morning meteor observing as the moon wanes and 
becomes just a thin sliver of light in the southeastern sky late in the
period. Observers who venture out on the morning of February 2 will also
have an added treat of seeing the moon very close to the planet Venus.

This is a transition period for radiants located near the anthelion
point opposite the sun. The International Meteor Organization shower
list has the Delta Cancrids ending and the Virginids starting up this
week. The radiant takes a broad jump from the Leo-Cancer border into
central Leo.  It would be interesting to verify this and to see if in
fact more activity comes from central Leo rather than farther west. This
Saturday morning the Delta Cancrid radiant would be located near 9:12
+17 which is almost directly between the famous "Beehive" cluster in
Cancer and Regulus, the brightest star in Leo. The Virginid radiant is
listed at 10:24 +16 which is roughly 10 degrees southeast of Regulus.
Both of these radiants would produce medium slow meteors with an 
occasional fireball. Activity from this portion of the sky is visible
during the later evening hours but any activity would be best seen
between 1 and 2am when the radiants are located high in the southern
skies.

Morning observers may wish to try verifying any activity from a possible
Xi Bootid radiant which on Saturday morning would be located near 14:07
+22, which is just northwest of the very bright star Arcturus. Arcturus
rises near 2300 (11pm) local time this time of year and is best seen
during the last few hours before dawn when it is located high in the
southeastern sky. Any activity from this radiant would expected to be
medium fast since it is located fairly close to the Earth's apex.
Activity from this part of the sky was first noticed by George Gliba in 
1997. He counted 26 meteors during seven and one half hours of observing
during the period February 6-9. In 1999, Pierre Martin counted 4 more
possible Xi Bootids on January 26 so it seems we may be already within 
the time frame of activity for this display. There will be more on this
possible display next week.

Observers located in the tropics and the Southern Hemisphere have no
less than five radiants now active in the Centaurus-Vela region of the
sky. The strongest of these radiants is the Alpha Centaurids which is
currently located near 13:16 -57, which is just a few degrees east of
the Southern Cross. Other active radiants include the Alpha Carinids
6:16 -54, Delta Velids 8:16 -50, Omicron Centaurids 10:56 -51, and the
Theta Centaurids 12:20 -32. Unfortunately all of these radiants are very
weak producing much less than one shower member per hour to the overall
activity. During any given hour this week these showers may add perhaps
1-2 meteors to the overall activity. Velocities range from slow (25 kps)
for the Alpha Carinids to fast (60 kps) for the Theta Centaurids. The
Delta Velids and the Omicrom Centaurids have medium speeds while the
Alpha Centaurids almost match the Theta Centaurids in velocity (56 vs.
60).

Finally sporadic rates would be near 4 per hour during evening hours and
up to 8 per hour during the morning hours as seen from rural observing
sites. I would expect a 3 hour morning observing session from rural 
locations to produce 30 meteors this week. Those with limiting
magnitudes less than 6.0 can expect to see much less especially if the
skies are hazy.

Clear Skies!

Robert Lunsford
AMS Visual Coordinator
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