Meteor Activity Outlook for January 1-7, 2011

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 new
phase on Tuesday January 4th. At this time the moon lies near the sun and is not visible
at night. This will be the best time of the month to view meteor activity as the
moon will not interfere plus the meteor rates will be at their highest. The
estimated total hourly rates for evening observers this week is near eight from the
northern hemisphere and two for observers south of the equator. For morning
observers the estimated total hourly rates should be near forty-five from the northern
hemisphere and twenty as seen from the southern hemisphere. 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 (the area of the sky where meteors appear
to shoot from) positions and rates listed below are exact for Saturday night/Sunday
morning January 1/2. 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 07:36 (114) +21. This area
of the sky lies in eastern Gemini, seven degrees south of the bright first magnitude
star Pollux (Beta Geminorum). This radiant is best placed near 0100 local standard
time (LST) when it lies on the meridian and is located highest in the sky. Due to
the large size of this radiant, any meteor radiating from Gemini, Canis Minor,
eastern Auriga, southern Lynx or Cancer could be a candidate for this shower.
Rates at this time should be near three per hour as seen from the northern
hemisphere and two 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.

The Alpha Hydrids (AHY) are active from December 30th through January 8th.
Peak activity occurred on December 31. Rates would most likely now be less than
one per hour, no matter your location. The radiant is currently located at 08:28 (127) -08.
This position lies in extreme western Hydra, fifteen degrees west of the second
magnitude star Alphard (Alpha Hydrae). The Alpha Hydrids are best seen near 0200
LST when the radiant lies highest above the horizon. At 45 km/sec. the Alpha Hydrids
produce mostly meteors of medium velocity.

Studies of the IMO’s video database by Sirko Molau and Juergen Rendtel has shown
an active radiant in Leo this time of year. The January Leonids (JLE) are
active from December 31st to January 5th with maximum activity occurring on January
1st. On the 1st the radiant is located at 09:46 (147) +24. This position lies in
western Leo just west of the third magnitude star Algenubi (Epsilon Leonis). This
is a very minor display with hourly rates of less than one expected, even at maximum
activity. They are best seen near 0300 LST when the radiant lies highest above the
horizon. At 54 km/sec. the January Leonids (JLE) produce mostly meteors of medium-swift
velocity.

The December Leonis Minorids (DLM) are active from a radiant located at 11:58
(173) +25. This position lies in a blank area of northeastern Leo, directly between
the bright stars Denebola (Beta Leonis) and Nu Ursae Majoris. These meteors are
best seen near 0500 LST when the radiant lies highest above the horizon. This shower
peaked on December 20th so current rates would be near two per hour as seen from the
northern hemisphere and one per hour as seen from south of the equator. At 64km/sec.
the December Leonis Minorids produce mostly swift meteors.

The Quadrantids (QUA) or January Bootids are active from January 1st through
the 10th. A sharp maximum is predicted to occur near 0100 Universal Time on the 4th.
This corresponds to 20:00 (8pm) EST and 17:00 (5pm) PST on the evening of January 3.
This is bad timing for viewers located in North America as the radiant will either
be low or beneath the northwestern horizon. At such low radiant elevations very
little Quadrantid activity can be expected to be seen. Your best bet is to wait
until the morning of the 4th when the radiant was risen in the northeastern sky.
From 0100 to dawn expect to see up to 25 Quadrantids per hour. Observers viewing
from eastern Europe and western Asia will have the maximum occur during the morning
hours when the radiant lies high in the sky. They can expect to see near 60 Quadrantids
per hour, perhaps more if the shower is especially active. The radiant is located at
15:21 (230) +49. This position lies in a bare region of extreme northern Bootes,
ten degrees northeast of the fourth magnitude star Beta Bootis. At 42 km/sec. the
Quadrantids produce meteors of medium velocity. During exceptional activity some
Quadrantid fireballs may be witnessed.

As seen from the mid-northern hemisphere (45N) one would expect to see
approximately fifteen Sporadic meteors per hour during the last hour before
dawn as seen from rural observing sites. Evening rates would be near three per hour.
As seen from the mid-southern hemisphere (45S), morning rates would be near thirteen
per hour as seen from rural observing sites and three per hour during the evening
hours. Locations between these two extremes would see activity between the
listed figures.

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