(meteorobs) Meteor Activity Outlook for April 27-May 3, 2013

[Robert Lunsford]

During this period the moon reaches its last quarter phase on Thursday May 2nd. At this time the moon is located ninety degrees west of the sun and rise near 0200 local daylight time (LDT) as seen from mid-northern latitudes. This weekend the waning gibbous moon will rise during the late evening hours and will severely hamper attempts at meteor observing the remainder of the night. The estimated total hourly meteor rates for evening observers this week is near three as seen from the northern hemisphere and four as seen from south of the equator. For morning observers the estimated total hourly rates should be near five as seen from the northern hemisphere and eight 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. Rates are reduced during this period due to the bright moon.

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 April 27/28. 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 list below presents a list of radiants that are expected to be active this week. Rates and positions are exact for Saturday night/Sunday morning. Details of each radiant will continue next week when there is less interference from the moon.

Anthelions (ANT) - 15:20 (230) -19   Velocity - 30km/sec.
Northern Hemisphere - 1 per hr.  Southern Hemisphere - 1 per hr

Nu Cygnids (NCY) - 21:20 (320) +44   Velocity - 42km/sec.
Northern Hemisphere - <1 per hr.   Southern Hemisphere - <1 per hr

Eta Aquariids (ETA) - 22:12 (333) -04   Velocity - 68km/sec.
Northern Hemisphere -  1 per hr.   Southern Hemisphere - 2 per hr

Clear Skies!
Robert Lunsford
American Meteor Society