[Prev][Next][Index][Thread]
(meteorobs) Meteor Activity Outlook for January 19-25, 2001
The moon is new on Wednesday January 24 meaning that from now to the
24th each night gets progressively better approaching that date. This
weekend the moon will be a thin waning crescent in the late morning sky
and not much of a bother. The positions listed below are exact for
Saturday night/Sunday morning January 20/21. The positions do not change
greatly day to day so these positions may be used during this entire
period.
The Gamma Velid activity is winding down and soon will end. The radiant
is located at 08:52 (133) -51 which lies in western Vela situated just
north of the "False Cross". This area of the sky is best placed near
0100 local time. I would not expect any of this activity to be seen from
the Northern Hemisphere and rates of only 1-2 per night from far
southern observing sites. The Gamma Velids are of medium velocity which
means that they would appear to move slowly if seen near the radiant and
only a bit faster if seen high in the sky and far from the radiant.
The Antihelion radiant is now located at 09:00 (135) +16. This area of
the sky is located in eastern Cancer some 5 degrees southeast of the
naked eye star cluster known as the Beehive. Any slow meteor from this
area or western Leo is a good candidate for this shower. This area of
the sky is best placed near 0100 local time when it lies on the
meridian. At this time expect to see perhaps 2 to 3 meteors per hour
from this source. Those who share reports with the IMO should label
these meteors as Delta Cancrids (DCA).
The Alpha Hydrids is an obscure winter shower listed among the radiants
of the Dutch Meteor Society. Maximum activity is reported to occur on
January 13 with a maximum zenith hourly rate of only 2. The current
radiant is located at 09:12 (138) -13. This area of the sky is located
in southwestern Hydra some 5 degrees southwest of the bright orange star
Alphard (Alpha Hydrae). It reaches the meridian near 0100. At this time
it is located highest in the sky and best placed for viewing. Any
shower members would have medium velocities meaning that meteors seen
near the radiant or the horizon would be slow and those seen high in the
sky away from the radiant would be of average speed.
The Alpha Crucids is another obscure southern radiant producing little
activity. Australian observers report a maximum zenith hourly rate of
only 3. Maximum activity occurs on January 14 so visual rates this
week would most likely be less than 1 per hour. The Alpha Crucid radiant
is located at 13:16 (199) -65. This area of the sky is located in
extreme northeastern Musca just on the outskirts of the "Coal Sack", a
famous naked eye obscuring nebula well known to observers in the
Southern Hemisphere. This area of the sky is not visible north of 25
degrees north latitude and is best seen from far southern locations just
before dawn. These meteors are of medium velocity comparable to the
better known Lyrids of April.
The Northern Apex radiant is now located at 14:00 (210) +04. This
position lies in north-central Virgo 3 degrees north of the 4rd
magnitude star Tau Virginis. Since this radiant is also diffuse any
meteors from northern Virgo or southern Bootes would be a good
candidate. As seen from the Northern Hemisphere this source should
produce 2-3 meteors per hour near dawn. Observers in the Southern
Hemisphere should see similar rates. These meteors should be reported as
Coma Berenicids (COM) by observers reporting to the IMO.
The Southern Apex source lies exactly 30 degrees south of its northern
counterpart at 14:01 (210) -26. This position lies in extreme eastern
Hydra close to the 3rd magnitude star Pi Hydrae. Like the northern
apex these meteors are best seen toward dawn when the radiant lies
highest above the horizon in a dark sky. Any meteor from extreme eastern
Hydra, northern Centaurus, southeastern Virgo, or southwestern
Libra could possibly be a good candidate from this source. As seen from
the Northern Hemisphere this source should produce 1-2 meteors per hour
near dawn. Rates seen from the Southern Hemisphere should be a bit
better at 2-3 per hour.
The Sporadic rates for the Northern Hemisphere are now in decline and
will do so until June. One would expect to see perhaps 7-8 random
meteors per hour during the last hours before dawn from rural observing
sites. During the evening hours perhaps 3-4 random meteors can be seen
per hour. Rates seen from the Southern Hemisphere would now be a bit
better than those seen in the Northern Hemisphere with perhaps 8-10
random meteors being seen per hour during the late morning hours.
Meteors from Coma Berenices? Alastair McBeath, vice president of the
International Meteor Organization has issued an observing alert this
week for possible meteors from the constellation of Coma Berenices. The
suspected radiant lies in central Coma at 12:32 (188) +22. Maximum
activity is expected on January 24 but observations before and after
this date are very important too! The radiant is in the sky all morning
long but is best placed near 0400 local time when it lies on the
meridian. This would be in a due south direction for observers north of
22 degrees N. latitude and due north for observers south of 22 degrees
N. latitude. With an entry velocity near 60 km/sec. these meteors would
appear to travel slowly if seen near the radiant or near the horizon. If
seen far from the radiant and high in the sky then they would appear to
travel quite swiftly. Rates are expected to be low but even a report of
zero activity is important. Video, photographic, and plotting would be
valuable activities in order to confirm any activity. This is one case
where observers MUST face close to the radiant to help determine shower
association. Looking further than 15 degrees away from the radiant
introduces a greater possibility of sporadic meteors being recorded as
shower members. Let us know what you see or don't see as soon as
possible!
Clear Skies!
Robert Lunsford
AMS Visual Program Coordinator
To UNSUBSCRIBE from the 'meteorobs' email list, use the Web form at:
http://www.tiacdot net/users/lewkaren/meteorobs/subscribe.html