Meteor Activity Outlook for April 3-9, 2010

Meteor activity picks up a bit during April as two major showers
are active during the month. The first of these, the Lyrids, are active from the 16th through the
25th, with a pronounced maximum on the 22nd. The Eta Aquariids start appearing near the 28th and
reach maximum activity during the first week in May. Sporadic rates are low but steady as seen
from the mid-northern hemisphere (45 N). Sporadic rates seen from the mid-southern hemisphere
(45 S) rise this month toward a maximum in July.

During this period the moon reaches its last quarter phase on
Tuesday April 6th. At this time the moon lies ninety degrees west of the sun and rises near 0100
local daylight time (LDT) for the mid-northern latitude observer. The estimated total hourly rates
for evening observers this week is near three for northern observers and four for those viewing
from south of the equator. For morning observers the estimated total hourly rates should be near
nine from the northern hemisphere and eleven 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. Morning rates are reduced due to moonlight.

The radiant positions and rates listed below are exact
for Saturday night/Sunday morning April 3/4. 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:

The wide Antihelion (ANT) radiant is now centered at 13:48 (207) -11. This area of the sky
lies in eastern Virgo, four degrees east of the bright first magnitude star Spica (Gamma Virginis).
This radiant is best placed near 0200 local daylight time (LDT) when it lies on the meridian and
is located highest in the sky. Due to the large size of this radiant, any meteor radiating from
Corvus, eastern Hydra, Libra, or Virgo could be a candidate for this shower. Rates at this time
should be near two per hour no matter your location. With an entry velocity of 30 km/sec., the
average Antihelion meteor would be of medium-slow speed.

The team of Sirko Molau and Juergen Rendtel have discovered a weak radiant active at this time in
the constellation of Cygnus. Video data shows that the Zeta Cygnids (ZCY) are active from
March 27th through April 18th. Maximum activity occurs on the morning of April 6th. The radiant is
currently located at 19:56 (299) +40. This position lies in central Cygnus, six degrees west of
the second magnitude star Sadr (Gamma Cygni). The radiant is best placed during the last dark hour
before dawn, when it lies highest above the horizon in a dark sky. At 44km/sec. the Zeta Cygnids
would produce meteors of medium velocity. Expected rates are near one per hour during the last
dark hour before dawn. Due to the northerly declination, these meteors are not well seen from
south of the equator.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately six
sporadic meteors per hour during the last hour before dawn as seen from rural observing sites.
Evening rates would be near two per hour. As seen from the mid-southern hemisphere (45S), morning
rates would be near nine per hour as seen from rural observing sites and three per hour during
the evening hours. Locations between these two extremes would see activity between the listed figures.
Morning rates are reduced due to lunar glare.

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