(meteorobs) Meteor Activity Outlook for April 7-13, 2006

[Robert Lunsford]

With the arrival of April, observers in the northern hemisphere still suffer
with low sporadic rates, especially during the evening hours. Observers
south of the equator will witness increasing sporadic rates with the maximum
activity occurring in July. The overall meteor activity is better than March
due to the activity of the two major showers; the Lyrids and the Eta
Aquarids. The Eclipticid radiant begins the month in the constellation of
Virgo. By the 15th, the Virginid portion of the eclipticid activity becomes
quite low and few meteors are seen. During the last week of the month a
strong center of eclipticid activity becomes active in the constellation of
Libra. Many of these meteors can be noticed while viewing early Eta Aquarid
activity. Due to the southerly position of the Eclipticids this time of
year, they are slightly better seen south of the equator. The most favorable
time to view meteor activity this month would be near the new moon, which
occurs on April 27. April is also prime time for viewing fireballs. No exact
radiant has been determined for these fireballs but a good number of them
are associated with the Eclipticid radiant. Therefore the hours near 0200
(local daylight saving time) are the most favorable time to view these
events. Still, many have been witnessed during the early evening hours, when
the radiant area lies low in the southeastern sky.

The moon reaches its full phase on Thursday April 13. At that time the moon
will be rise as the sun sets and set as the sun rises. This weekend the
waxing gibbous moon sets during the early morning hours allowing a window of
opportunity to view under dark conditions. This window will shrink as the
week progresses. The estimated total hourly rates for evening observers this
week is near one for observers in the northern hemisphere and two for those
south of the equator. For morning observers the estimated total hourly rates
should be near seven for those located in the Northern Hemisphere and ten
for those in the Southern Hemisphere. 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. Evening rates are reduced due to moonlight.

The radiant positions listed below are exact for Saturday night/Sunday
morning April 8/9. 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. 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 active this week:

The Eclipticid (ECL) radiant is now centered at 13:28 (202) -07. This area
of the sky is located in central Virgo, four degrees north of the first
magnitude star Spica (Alpha Virginis). This radiant is best placed near 0200
local daylight time when it lies on the meridian and is highest in the sky.
Rates should be near one per hour for those north of the equator and two per
hour south of the equator. With an entry velocity of 30 km/sec., the average
Eclipticid meteor would be of medium-slow speed. This radiant is a good
source of fireballs now through the end of April. Those who send reports to
the I.M.O. should label these meteors as Virginids (VIR).

The Delta Pavonids (DPA) are an obscure shower listed among the radiants of
the Dutch Meteor Society. They list the ZHR's as five but recent
observations fail to show much activity at all. The predicted date of
maximum activity was March 28. Current rates would most certainly be less
than one per hour. The radiant currently lies at 22:28 (337) -67. This area
of the sky is located near the fourth magnitude star Delta Tucanae. This
area of the sky is too far south to be seen north of the northern equatorial
areas. Only observers living in far southern locations such as Australia,
South Africa, and southern South America have any chance of seeing activity
from this radiant. The best time to view possible activity is just before
the start of morning twilight, when the radiant lies highest in a dark sky.
With an entry velocity of 60 kilometers per second, a majority of these
meteors will appear to move swiftly.

The Sporadic rates for the Northern Hemisphere are now nearing their annual
minimum activity. One would expect to see perhaps six random meteors per
hour during the last hours before dawn from rural observing sites. During
the evening hours perhaps one random meteor can be seen per hour. Sporadic
rates seen from the southern hemisphere are now increasing toward a
secondary maximum in July. One would see approximately eight random meteors
per hour during the late morning hours and two per hour during the evening.
Evening rates from all areas are reduced due to moonlight.

Eclipticids (ECL) 13:28 (202) -07
Northern Hemisphere 1  Southern Hemisphere  2

Delta Pavonids (DPA) 22:28 (337) -67
Northern Hemisphere 0 - Southern Hemisphere >1

*For a detailed explanation on the different classes of meteor showers and
other astronomical terms, please visit:
http://www.amsmeteors.org/showers.html#X2006

Clear Skies!
Robert Lunsford
American Meteor Society