This week will see the moon start to enter the morning sky late in the
period. This weekend will still be an excellent time to view meteor
activity as the moon will have set by midnight local daylight time. The moon
reaches its first quarter phase on Monday August 23. At this time the moon
lies ninety degrees east of the sun and will set near 0100 local daylight
time. The estimated total hourly rates for evening observers this week
should be near three for those in the Northern Hemisphere and one for those
observers south of the equator. For morning observers the estimated total
hourly rates should be near eighteen for those located in the Northern
Hemisphere and twelve for those in the Southern Hemisphere. Evening rates
are reduced due to moonlight. These rates assume that you are watching from
rural areas away from all sources of light pollution. 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 positions listed below are exact for Saturday night/Sunday
morning August 21/22. 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 libraries) 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 location. 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 last rise later in the night. This list also
provides the order of ascending velocity for each radiant with those listed
first usually being much slower than those last on the list. Velocity should
not be the prime factor for shower association as all showers can produce
slow meteors. Slow meteors can be produced from normally swift showers, such
as the Leonids, when meteors appear near the radiant or close to the
horizon. The true velocity is only revealed in shower members seen far from
the radiant and high in the sky.

These are the showers that may be observed this week:

The Kappa Cygnids (KCG) are active from a wide radiant located at 19:04
(286) +59. This position is located in southern Draco, six degrees northwest
of the fourth magnitude star Kappa Cygni. Current rates would be near one
shower member per hour. A large percentage of these meteors are bright,
often fireball class meteors with brilliant colors. With an entry velocity
of 25 km/sec. most of these meteors will appear to travel slower than
average. The radiant is best placed near 2300 Local Daylight Time (11pm LDT)
when it lies nearly overhead for much of the Northern Hemisphere. Due to its
high northern declination this activity is not well seen from the Southern
Hemisphere.

The North Iota Aquarids (NIA) are active from a radiant currently located at
21:56 (329) -06. This area of the sky is located in central Aquarius, five
degrees east of the third magnitude star Sadalsuud (Beta Aquarii). Maximum
activity occurs on August 19 with an expected ZHR of three. Current rates
would be near two shower member per hour, depending on your latitude. At 31
km/sec. the NIA´s are of average velocity. This radiant is most active near
0100 LDT when it lies highest in the southern sky.

The Anthelion radiant is now centered at 22:52 (343) -06. This area of the
sky is located in central Aquarius, five degrees west of the fourth
magnitude star Phi Aquarii Since this radiant is large and diffuse, any slow
to medium speed meteor from eastern Capricornus, southwestern Pegasus,
western Pisces or central Aquarius could be a candidate for this shower. The
center of this area is best placed near 0100 local standard time when it
lies on the meridian and is highest in the sky. At this time expect to see
two shower members per hour  no matter your location.  At this time of year
the Anthelion radiant overlaps both the North Delta Aquarid radiant and the
Nouth Iota Aquarids so distinguishing between these showers will be
difficult but not impossible if you face toward this general area of the
sky.

Unlike most of the annual showers the antihelion source is produced by
debris from unknown objects orbiting in a direct motion like the earth.
These objects are most likely asteroids, which produce stony and metallic
debris whose density is much greater than material produced by comets. There
is also the possibility that some of this activity may be caused by the
"Jupiter family of comets", comets which have been altered by Jupiter´s
gravity into much shorter orbits. This material collides with the earth on
the inbound portion of its orbit, before its closest approach to the sun.
Therefore we best see them just after midnight when we are facing the
direction from which this activity appears. The antihelion source is active
all year from an area of the sky nearly opposite that of the sun. The center
of this source will move approximately one degree eastward per day and
travels through many different constellations over the course of a year. It
may make sense to list these meteors as anthelions or "ANT" but a majority
of meteor organizations prefer that you list them from the constellation in
which the radiant is currently located or the constellation where the shower
reaches maximum activity. At this time of year the IMO has no designation
for the anthelion radiant as it overlaps several other radiants as it moves
through Capricornus and Aquarius during July and August.

The North Delta Aquarids (NDA) are currently active from a radiant located
at 23:00 (345) -03. This area of the sky is located in western Pisces, five
degrees south of the faint star Beta Piscium. This position is also close to
the anthelion radiant and care must be taken to distinguish meteors from
these sources. At 42 km/sec. the NDA´s are a bit faster than the antihelion
meteors. This radiant is most active between 0200 and 0300 LDT when it lies
highest in the sky. Like many of the radiants active this time of year the
NDA´s are better seen from areas south of the northern tropics or 30 degrees
north latitude. With maximum activity occurring back on August 8, current
hourly rates, seen from the southern tropics, would be near one per hour.

The Pi Eridanids (ERI) are minor shower listed among the radiants of the
Dutch Meteor Society. The peak activity is listed as August 27 with a ZHR of
four. The current radiant position lies at 03:08 (047) -13, which places it
in western Eridanus, four degrees southeast of the fourth magnitude star Eta
Eridani. The radiant is best placed just before the start of morning
twilight, when it lies highest above the horizon in a dark sky. At
59km/sec., a majority of these meteors will move swiftly. Brighter shower
members should produce trains.  The Gamma Doradids (GDO) are another obscure
minor shower listed among the radiants of the Dutch Meteor Society. The peak
activity is listed as August 30 with a ZHR of five. The current radiant
position lies at 03:48 (057) -52, which places it in eastern Horologium some
four degrees west of the 3rd magnitude star Gamma Dorado. Due to the extreme
southern declination, this shower is only visible from the northern tropics
southward. The radiant is best placed just before the start of morning
twilight. At 41km/sec., these meteors are of average velocity.

The Northern Apex radiant is now centered at 03:52 (058) +35. This position
lies in southern Peresus, one degree southwest of the fourth magnitude star
Xi Persei. This area of the sky is best placed for viewing during the last
dark hour before dawn when it lies highest in the sky. Since this radiant is
large and diffuse, any meteor from southern Perseus, northwestern Taurus,
northern Aries or western Auriga could be a candidate from this source.
Rates would be now close to three per hour for observers north of the
equator and less than one per hour for those observers south of the equator.
Observers who view far from this radiant must be careful not to list these
meteors as late Perseids or early Alpha Aurigids.

Like the anthelion area, both apex areas are active all year long and travel
approximately one degree eastward per day. Unlike the anthelion debris,
these particles orbit the sun in a retrograde motion opposite that of the
earth and are most likely produced by unknown comets. They strike the earth
after their closest approach to the sun. Since they are moving in opposite
directions these particles strike the earth at tremendous velocities often
creating bright meteors with persistent trains. These particles strike the
earth on the morning side of earth and are best seen just before morning
twilight while the sky is still perfectly dark. This is not really a
"shower" per se, but an artificial radiant created by the Earth´s motion
through space. Meteors from both branches are normally included in the
sporadic count. I feel it is a worthy project to see if it is possible to
distinguish these meteors from the normal sporadic background. On rare
occasions there are meteors with a zero inclination that radiate precisely
from the apex point on the ecliptic, exactly 90 degrees west of the sun. In
simplistic terms, these meteors are seldom seen since the Earth "sweeps
clean" much of the material that shares the same orbit as our planet. Much
more material is located just north and south of the earth´s orbit with
slightly higher or lower inclinations. This creates the northern and
southern branches of the apex activity.

The Southern Apex source lies exactly 30 degrees south of its northern
counterpart at 03:52 (058) +05. This position lies in southwestern Taurus,
fifteen degrees southwest of the first magnitude star Aldebaran (Alpha
Tauri). Like the northern apex, these meteors are best seen toward dawn when
the radiant lies highest above the horizon in a dark sky. Since this radiant
is also large and diffuse, any meteor from eastern Cetus, southeastern
Aries, western Orion, northwestern Eridanus or southern Taurus could be a
candidate from this source. Rates would now be two per hour regardless of
your location.

The Perseids (PER) reached an impressive maximum on the morning of August
12. Rates this weekend are continuing to fall as the Earth is moving away
from the core of the Perseid material. Current rates would be near two per
hour falling to less than one per hour later in this period. The current
radiant position lies at 04:00 (060) +59, which is located in southern
Camelopardalis, ten degrees northeast of the second magnitude star Mirfak
(Alpha Persei). The radiant is well placed for those in the Northern
Hemisphere during the last few hours before dawn. Due to the high northern
declination (celestial latitude) of the radiant, rates seen from the
Southern Hemisphere are very low or non-existent. At 59km/sec., Perseid
meteors are usually swift, often exhibiting persistent trains.

The Sporadic rates for the Northern Hemisphere are now increasing. One would
expect to see perhaps eight random meteors per hour during the last hours
before dawn from rural observing sites. This estimate and the morning
estimate for the Southern Hemisphere do not include the apex meteors listed
above. During the evening hours perhaps two random meteors can be seen per
hour from the Northern Hemisphere. Rates seen from the Southern Hemisphere
are now lower than those seen in the north with perhaps six random meteors
being seen during the late morning hours and one per hour during the
evening. Evening rates are reduced due to moonlight.

Clear Skies!
Robert Lunsford
AMS Operations Manager

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