(meteorobs) Meteor Activity Outlook for July 2-8, 2004

[Robert Lunsford]

The moon reaches its full phase on Friday July 2. At this time it is located
180 degrees from the sun and rises as the sun sets and sets as the sun
rises. This weekend and for the remainder of this period, the moon will be
present in the early morning sky, limiting the meteor activity to be seen.
The sources of meteors listed below are active during this period but will
be difficult to observe. If your sky is transparent and the limiting
magnitude exceeds +5.0, then you may be able to achieve some success at
observing during this period. The estimated total hourly rates for evening
observers this week is near one for those in the Northern Hemisphere and two
for those located in the Southern Hemisphere. For morning observers the
estimated total hourly rates should be near six for those located in the
Northern Hemisphere and eight 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. Rates are reduced this week due
to intense moonlight.

The positions listed below are exact for Saturday night/Sunday morning July
3/4. The positions do not change greatly day to day so these positions 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 radiants below are listed in a west to east manner in order
of right ascension (celestial longitude). The radiants 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.

The detailed descriptions of each shower will return next week when
moonlight becomes less of a factor.

Alpha Capricornids       18:56  (284)   -16   Hourly Rate =
                                     0 Northern Hemisphere, 1 Southern

Antihelion (Sagittarids)  19:44  (296)   -21   Hourly Rate =
                                    1 Northern Hemisphere, 2 Southern

Northern Apex             00:44  (011)   +20   Hourly Rate =
                                    1 Northern Hemisphere, 0 Southern

Southern Apex             00:44  (011)    -10   Hourly Rate =
                                    1 Northern Hemisphere, 1 Southern

Clear Skies!
Robert Lunsford
AMS Operations Manager