[Prev][Next][Index][Thread]
(meteorobs) Meteor Activity Outlook for February 16-22, 2001
The moon reached its last quarter phase on on Wednesday February 14 and
is now becoming less of a problem with each passing morning this week.
This weekend would be a good time to watch as the crescent moon will
rise well after midnight not pose much of a problem. The list of active
southern radiants below may appear impressive but only the Alpha
Centaurids produce any notable activity. The remainder are weak showers
that have actually been removed from the IMO radiant list. They are
listed here to encourage observers to continue monitoring these areas of
the sky just in case any unusual activity should occur. Observers south
of the equator and those in low northern latitudes should take advantage
of the many radiants best seen by them at this time of year. The
positions listed below are exact for Saturday night/Sunday morning
February 17/18. The positions do not change greatly day to day so these
positions may be used during this entire period.
The Delta Velids is a southern radiant listed by the Dutch Meteor
Society. Maximum activity was predicted to occur on February 13 with a
ZHR of only 1. The current radiant position is 08:52 (133) -53. This
area of the sky lies in southwestern Vela just a few degrees north of
the "False Cross". Meteors from this radiant would be best seen just
before midnight local time. 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 Delta Leonids are now active from a radiant located at 10:48 (162)
+18. This area of the sky is located in central Leo roughly midway
between the bright stars Theta and Delta Leonis. Like the antihelion
radiant this radiant is best placed near 0100 local time. Meteors from
this would also have similar velocities to the antihelion radiant. One
must be careful in separating the two active areas close together in the
sky. The Delta Leonids will not reach maximum activity until February
24. Expect rates of less than 1 per hour this week.
The Antihelion radiant is now located at 10:52 (163) +07. This area of
the sky is located in south-central Leo near the border of Sextans. Any
slow to medium speed meteor from this area or Sextans 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 Virginids (VIR).
The Omicron Centaurids is one of three radiants now active in this
region of the sky. It is also the weakest by only producing a ZHR of 2
when it reached maximum activity on February 13. The current radiant
position lies at 12:04 (181) -58. This area of the sky is now actually
located in western Crux very close to Delta Crucis, the faintest star of
the cross. Meteors from this radiant would be best seen near 0200
local time. With an entry velocity of 51 km/sec. shower members would
appear medium fast if seen far from the radiant and high in the sky. If
seen close to the radiant or close to the horizon they would appear
to travel quite slowly.
The Theta Centaurids is the only radiant of the trio that can reliably
be seen from north temperate latitudes. This shower reached a maximum
ZHR of 4 on February 13. Activity this week is likely to be slightly
less now that we are past maximum. The current radiant position is
located at 14:24 (216) -43. This area of the sky is located in western
Lupus just 2 degrees southwest of the bright star Eta Centauri. Meteors
from this radiant would be best seen near 0400 local time. The Theta
Centaurids produce the fastest meteors of the trio at 60 km/sec. This
velocity is similar to the well known Perseids of August.
The Alpha Centaurids is the strongest of the Centaurid radiants. Maximum
activity was on February 7 so we are now viewing the down slope of the
ACE's activity curve. The current radiant position is 14:56 (224)
-62. This position actually lies in Circinus only 2 degrees southeast of
the brilliant star Rigel Kentaurus (Alpha Centauri). Meteors from this
radiant would also be best seen near 0400 local time. With an entry
velocity of 56 km/sec. these meteors would appear to travel slowly if
seen near the radiant or near the horizon. If seen well away from the
radiant and high in the sky then they would appear to move quite
swiftly.
The Northern Apex radiant is now located at 15:52 (238) -05. This
position lies in extreme northeastern Libra 2 degrees southeast of the
3th magnitude star Mu Serpentis. This area of the sky is best placed for
viewing during the last dark hour before dawn. Since this radiant is
diffuse any meteors from Serpens Caput or northern Libra 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.
The Southern Apex source lies exactly 30 degrees south of its northern
counterpart at 15:52 (238) -35. This position lies in northwestern Lupus
just 1 degree south of the 4th magnitude star Chi Lupi. 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 northern
Lupus or south-central Scorpius could possibly be a good candidate
from this source. As seen from the Northern Hemisphere this source
should produce at least 1 meteor per hour near dawn. Rates seen from the
Southern Hemisphere should be better at perhaps 3-4 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 6-7 random
meteors per hour during the last hours before dawn from rural observing
sites. During the evening hours perhaps 2-3 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 7-9
random meteors being seen per hour during the late morning hours.
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