(meteorobs) Meteor Activity Outlook for November 6-12, 2010

Robert Lunsford lunro.imo.usa at cox.net
Thu Nov 4 15:57:15 EDT 2010


As seen from the northern hemisphere, meteor rates continue to be strong in
November. While no major activity is expected this month, the two Taurid
radiants plus the Leonids keep the skies active. The addition of strong
sporadic rates make November one of the better months to view meteor
activity from north of the equator. Skies are fairly quiet as seen from the
southern hemisphere this month. Activity from the three showers mentioned
above may be seen from south of the equator, but the sporadic rates are much
lower than those seen in the northern hemisphere.

During this period the moon reaches its new phase on Saturday November 6th.
At this time the moon lies near the sun and cannot be seen at night. This
will be the best time to view meteor activity this month. The Taurids will
be producing many slow meteors all night long while the sporadic rates will
also remain high. The estimated total hourly rates for evening observers
this week is near six from the northern hemisphere and four for observers
south of the equator. For morning observers the estimated total hourly rates
should be near twenty four from the northern hemisphere and fourteen 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
November 6/7. 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:

Sirko Molau and Juergen Rendtel's studies of video radiants has revealed
that activity from the famous Andromedid shower, noted for intense storms
during the 19th century, may still be seen throughout November. The current
position of the large radiant is 01:27 (022) +27. This position lies in a
sparse area of northeastern Pisces. The nearest bright star is third
magnitude Alpha Trianguli, which lies five degrees to the northeast. Visual
activity is expected to be low, but detectable. An inconspicuous maximum
occurs on November 12. The Andromedid meteors are best seen near 2200 (10pm)
LST (Local Standard Time) when the radiant lies on the meridian. At
19km/sec., the average Andromedid will appear as a very slow moving meteor.
Sirko mentions that these meteors are "conspicuously slow and of almost
constant activity" during this period.

The center of the large Northern Taurid (NTA) radiant lies at 03:38 (055)
+22. This area of the sky is located in western Taurus, two degrees
southwest of the famous naked eye open cluster known as the Pleiades. These
meteors are best seen near 0100 LST, when the radiant lies highest above the
horizon. This shower peaks on November 13, so rates are slowly increasing.
Current rates would be near three per hour, no matter your location. Meteors
from the Northern Taurids strike the atmosphere at 29km/sec., which would
produce meteors of slow velocity. This shower is also responsible for many
of the fireball reports seen in November.

The center of the large Southern Taurid (STA) radiant lies at 03:42 (056)
+14. This area of the sky is located in western Taurus, ten degrees south of
the Pleiades. The meteors are also best seen near the meridian near 0100
LST. We are now well past the October 10 maximum for this shower but rates
will still remain near two per hour, no matter your location. Striking the
atmosphere at 29 km/sec., the average Southern Taurid meteor travels slowly
through the skies. This shower is also responsible for many of the fireball
reports seen in October.

The Orionids (ORI) reached maximum activity on October 22nd. Some activity
may still be seen during the morning hours from a radiant located at 07:14
(109) +16. This position lies in southern Gemini, close to the faint star
Lambda Geminorum. The radiant is best placed on the meridian near 0400 LST.
Current rates should be near two per hour no matter your location. At
67km/sec., the average Orionid is swift.

The Leonids (LEO) are just now coming to life from a radiant located at
09:50 (148) +25. This position lies in western Leo only one degree north of
the third magnitude star Epsilon Leonis. Maximum activity is still more than
a week away so current rates would most likely be less than one per hour. At
71km/sec., the average Leonid is swift with a high percentage of trains.
These meteors are best seen during the last hour before the onset of morning
twilight, when the radiant lies highest above the horizon in a dark sky.

As seen from the mid-northern hemisphere (45N) one would expect to see
approximately sixteen sporadic meteors per hour during the last hour before
dawn as seen from rural observing sites. Evening rates would be near four
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.

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

Andromedids (AND) - 01:27 (022) +27   Velocity - 19km/sec.
Northern Hemisphere - <1 per hr. Southern Hemisphere - <1 per hr

Northern Taurids (NTA) - 03:38 (055) +22   Velocity - 29km/sec.
Northern Hemisphere - 3 per hr. Southern Hemisphere - 3 per hr.

Southern Taurids (STA) - 03:42 (056) +14   Velocity - 29km/sec.
Northern Hemisphere - 2 per hr. Southern Hemisphere - 2 per hr.

Orionids (ORI)  - 07:14 (109) +16   Velocity - 67km/sec.
Northern Hemisphere - 2 per hr. Southern Hemisphere - 2 per hr

Leonids (LEO)  - 09:50 (148) +25   Velocity - 71km/sec.
Northern Hemisphere - <1 per hr. Southern Hemisphere - <1 per hr

*For a detailed explanation on the different classes of meteor showers and
other astronomical terms, please visit:
http://www.amsmeteors.org/showers.html#X2010

Clear Skies!
Robert Lunsford
American Meteor Society





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