Meteor Activity Outlook for January 11-17, 2008

January sees a peak of sporadic activity for the southern hemisphere while
rates seen north of the equator begin a steady downward turn that continues
throughout the first half of the year. The sporadic activity is good for
both hemispheres, but not as good as it was for northern observers in
December. Once the Quadrantids have passed the shower activity for January
is very quiet.

During this period the moon reaches its first quarter
phase on Tuesday January 15. At this time the moon will be located 90 degrees east of the
sun and will set near midnight. The estimated total hourly rates for evening observers
this week is near two no matter your location. For morning observers
the estimated total hourly rates should be near seventeen for those located in the
mid-northern hemisphere (45 N) and sixteen for those viewing from the mid-southern
hemisphere (45 S). These rates assume that you are watching from rural areas away
from all sources of light pollution. The actual rates will also depend on factors
such as personal light and motion perception, local weather conditions, alertness
and experience in watching meteor activity.

The radiant positions and rates listed below are exact
for Saturday night/Sunday morning January 12/13. These positions do not change
greatly day to day so the listed coordinates may be used during this entire period.
Most star atlases (available at science stores and planetariums) will provide maps
with grid lines of the celestial coordinates so that you may find out exactly where
these positions are located in the sky. A planisphere or computer planetarium program
is also useful in showing the sky at any time of night on any date of the year.
Activity from each radiant is best seen when it is positioned highest in the sky,
either due north or south along the meridian, depending on your latitude. It must
be remembered that meteor activity is rarely seen at the radiant position. Rather
they shoot outwards from the radiant so it is best to center your field of view so
that the radiant lies at the edge and not the center. Viewing there will allow you to
easily trace the path of each meteor back to the radiant (if it is a shower member)
or in another direction if it is a sporadic. Meteor activity is not seen from radiants
that are located below the horizon. The positions below are listed in a west to east
manner in order of right ascension (celestial longitude). The positions listed first
are located further west therefore are accessible earlier in the night while those
listed further down the list rise later in the night.

The following showers are expected to be active this week:

The wide Antihelion (ANT) radiant is now centered at 08:20 (125) +18. This area
of the sky lies in central Cancer, five degrees west of the fourth magnitude star
Delta Cancri. This radiant is best placed near 0100 local standard time when it lies on the
meridian and is highest in the sky. Actually any meteor from
Cancer could be a candidate for this shower. Rates at this time should be near two
per hour as seen from the northern hemisphere and one per hour for observers
located south of the equator. With an entry velocity of 30 km/sec., the
average Antihelion meteor would be of medium-slow speed.

Sirko Molau’s study of video radiants has revealed activity during the
period January 13-19, from an area in west-central Coma Berenices. This position
is similar to the Coma Berenicids but far enough away to be monitored by visual
means. Maximum occurs on January 16 with the radiant located at 12:24 (186) +19. This position lies ten degrees
northeast of the second magnitude star Denebola (Beta Leonis). This radiant
is best placed near 0500 LST when it lies on the meridian and is highest in the
sky. Rates are most likely less than one shower member per hour no matter
your observing location. At 60km/sec., the average meteor from this radiant
would be swift.

The Coma Berenicids (COM) are active from a radiant located at 13:08 (197)
+15. This area of the sky is located in a remote area of eastern Coma Berenices.
The nearest bright star is Arcturus (Alpha Bootis), located some fifteen degrees
to the northeast. Current rates would be near one shower member per hour no matter your location.
These meteors are best seen near 0600 local standard time when the radiant lies
highest above the horizon. At 65 km/sec. the Coma Berenicids will usually produce
meteors of swift velocity.

Sporadic rates are now slowly falling for observers in the northern
hemisphere and rising for those located south of the equator. One would expect to
see approximately fourteen random meteors during the last hour before dawn from rural
observing sites no matter your geographic location. During the first dark hour
after the end of evening twilight, perhaps two random meteors can be seen per
hour.

The table below presents a condensed version of the expected activity this week.
Rates and positions are exact for Saturday night/Sunday morning.