(meteorobs) Meteor Activity Outlook for March 7-13, 2015

Robert Lunsford lunro.imo.usa at cox.net
Thu Mar 5 15:52:10 EST 2015


During this period the moon will reach its last quarter phase on Friday March 13th. At that time the moon is located 90 degrees west of the sun and rises near 0100 local daylight saving time. This weekend the waning gibbous moon will rise during the late evening hours effectively ruining the remainder of the night for meteor observing. This entire period will be a poor time to try and view meteor activity due to the bright moon present during the morning hours. The evening hours are less effective but rates are low even with the absence of moonlight. The estimated total hourly meteor rates for evening observers this week is near 1 for observers situated at mid-northern latitudes and 3 for observers viewing from the southern tropics (latitude 25 S.). For morning observers the estimated total hourly rates should be near 3 for observers situated at mid-northern latitudes and 6 for observers viewing from the southern tropics. Morning rates are reduced during this period due to lunar interference. 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. Note that the hourly rates listed below are estimates as viewed from dark sky sites away from urban light sources. Observers viewing from urban areas will see less activity as only the brightest meteors will be visible from such locations.

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 March 7/8. 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.

These sources of meteoric activity are expected to be active this week. Details on each source will continue next week when interference from moonlight will be much less.

Anthelion (ANT) - 12:00 (180) -01  Velocity - 30km/sec. 
Northern Hemisphere - 2 per hr.   Southern Hemisphere - 2 per hr

Xi Herculids (XHE) - 16:56 (254) +49  Velocity - 35km/sec. 
Northern Hemisphere - <1 per hr.   Southern Hemisphere - <1 per hr
 
Clear Skies! 
Robert Lunsford 	 
American Meteor Society  	 	 	 	 	 	 



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