Meteor Activity Outlook for November 17-23, 2012

During this period the moon reaches its first quarter phase on Tuesday November
20th. At this time the moon is located ninety degrees east of the sun and will
set near 2300 (1100pm) local standard time (LST). This weekend the waxing
crescent moon will set during the early evening hours and will pose no problems
to meteor watchers. Later in the week the gibbous moon will limit good meteor
observing to the late morning morning before dawn. The estimated total hourly
meteor rates for evening observers this week is near four for observers located
at mid-northern latitudes and three for observers in mid-southern latitudes. For
morning observers the estimated total hourly rates should be near twenty eight
from the mid-northern hemisphere and twenty three from the mid-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. Rates are reduced during the evening hours due to moonlight.

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 November 17/18. 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 radiants are expected to be active this week:

Remnants from the famous Andromedid (AND) shower, noted for intense storms
during the 19th century, may still be seen throughout November. The current
position of this large radiant is 01:36 (024) +37. This position lies in eastern
Andromeda, three degrees east of the second magnitude star Mirach (Beta
Andromedae). The radiant is so diffuse that Andromedid meteors may be seen
coming from Triangulum, northern Pisces, as well as Andromeda. Visual activity
is expected to be low, but detectable. An inconspicuous maximum occurred on
November 9, when this source was the 5th most active radiant in the sky. The
Andromedid meteors are best seen near 2200 (10pm) local standard time (LST),
when the radiant lies on the meridian and lies highest in the sky. At 19km/sec.,
the average Andromedid will appear as a very slow moving meteor.

Studies of the IMO video database by Sirko Molau and Juergen Rendtel has
revealed another active radiant in Taurus this time of year. Now that the
Southern Taurids are no longer detectable, the Gamma Taurids (GTA) may be
distinguished within the Taurid complex. The Gamma Taurid radiant is centered at
04:04 (061) +15. This area of the sky lies in western Taurus, three degrees west
of the the 4th magnitude star Hyadum I (Gamma Tauri). The radiant is best placed
near 0100 LST, when it lies highest above the horizon. Maximum activity occurred
on November 10th so current rates would be near one shower member per hour, no
matter your location. Meteors from the Gamma Taurids strike the atmosphere at
27km/sec., which would produce meteors of slow velocity.

The Northern Taurids (NTA) are active from a radiant centered at 04:16 (064)
+24. This area of the sky lies in western Taurus just three degrees west of the
famous naked eye open cluster known as the Pleiades or the Seven Sisters. The
radiant is best placed near 0100 LST, when it lies highest above the horizon.
Maximum activity occurred on November 13th so current hourly rates would be near
three from the northern hemisphere and two from south of the equator. Meteors
from the Northern Taurids strike the atmosphere at 29km/sec., which would
produce meteors of slow velocity.

The November Orionids (NOO) are active from a radiant located at 05:28 (082)
+16. This area of the sky is located on the Orion/Taurus border, twelve degrees
east of the first magnitude orange star Aldebaran (Alpha Tauri).. The peak for
this radiant is not until November 30th, so rates would be less than than one
shower member per hour, no matter your location. This location is close to the
Taurid complex, but far enough east to be distinguishable. The faster velocity
of the November should help distinguish these meteors from the slower, but more
numerous Taurids. The radiant is best placed for viewing near 0200 LST when it
lies on the meridian and is highest above the horizon. With an entry velocity of
44 km/sec., the November Orionids would be of medium speed.

The last few meteors from the Orionids (ORI) will be seen this week. The radiant
is located at 08:00 (120) +15. This area of the sky is located on the
Gemini/Cancer border, twelve degrees northeast of the zero magnitude star
Procyon (Alpha Canis Minoris). The radiant is best placed for viewing near 0400
LST when it lies on the meridian and is highest above the horizon. Expected
hourly rates would be less than one no matter your location With an entry
velocity of 67 km/sec., most activity from this radiant would be swift.

The Leonids (LEO) are now the most active radiant in the sky, producing a dozen
shower members per hour during the last couple of hours before dawn. As the
weekend passes, these rates will fall to only 2-3 per hour. The radiant is
currently located at 10:16 (154) +22. This position lies in northwestern Leo,
within the “sickle” of Leo, two degrees northwest of the second magnitude double
star Algeiba (Gamma Leonis). The Leonid radiant is best placed during the last
hour before morning twilight when the radiant lies highest in a dark sky.
Leonids may be seen from the southern hemisphere but the viewing conditions are
not quite as favorable as those north of the equator.

Studies of the IMO video database by Sirko Molau and Juergen Rendtel has
revealed an active radiant in Draco this time of year. The November Iota
Draconids (NID) radiant is located at 12:36 (189) +70. This area of the sky lies
in western Draco close to the position occupied by the fourth magnitude star
Kappa Draconis. The radiant is best placed near 0100 LST, when it lies highest
above the horizon. Maximum activity occurs on November 26th so current rates
would be less than one shower member per hour, no matter your location. Due to
the high northerly declination of the radiant these meteors are not visible from
most of the southern hemisphere. Only southern equatorial regions would have any
chance of seeing activity from this source Meteors from the November Iota
Draconids strike the atmosphere at 43km/sec., which would produce meteors of
medium velocity.

As seen from the mid-northern hemisphere (45N) one would expect to see
approximately twelve 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 six
per hour as seen from rural observing sites and two per hour during the evening
hours. Locations between these two extremes would see activity between the
listed figures. Evening rates are reduced due to moonlight.

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