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.
SHOWER | DATE OF MAXIMUM ACTIVITY | CELESTIAL POSITION | ENTRY VELOCITY | CULMINATION | HOURLY RATE | CLASS* |
RA (RA in Deg.) DEC | Km/Sec | Local Standard Time | North-South | |||
Andromedids (AND) | Nov 12 | 01:27 (022) +27 | 19 | 22:00 | <1 - <1 | IV |
Northern Taurids (NTA) | Nov 13 | 03:38 (055) +22 | 29 | 01:00 | 3 – 3 | II |
Southern Taurids (STA) | Oct 10 | 03:42 (056) +14 | 29 | 01:00 | 2 – 2 | II |
Orionids (ORI) | Oct 22 | 07:14 (109) +16 | 67 | 04:00 | 2 – 2 | I |
Leonids (LEO) | Nov 18 | 09:50 (148) +25 | 71 | 07:00 | <1 - <1 | III |