Meteor Activity Outlook for March 14-20, 2009

March is the slowest month for meteor activity. No major annual showers are active and only two very weak minor showers produce activity this month. The sporadic rates continue a slow decline as seen from the mid-northern latitudes and mid-southern rates reach a first half minimum. There is not much to look forward to this month expect for the evening fireballs that seem to peak this time of year from the northern hemisphere. This could be due to the fact the antapex lies highest this time of year during the evening hours.

During this period the moon reaches its last quarter phase on Wednesday March 18th. At this time the moon lies 90 degrees west of the sun and rises near 0100 local daylight time. This weekend the waning gibbous moon will rise during the evening hours and will remain in the sky the remainder of the night. The meteor activity is weak under dark skies this time of year. The moonlight makes the situation even worse this week. The estimated total hourly rates for evening observers this week is near one as seen from the northern hemisphere and two for those situated south of the equator. For morning observers the estimated total hourly rates should be near four for those located in the mid-northern hemisphere (45 N) and five for those viewing from the mid-southern hemisphere (45 S). Locations between these two extremes would see activity between the listed figures. 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. Meteor rates are reduced during this period due to lunar interference.

The radiant positions and rates listed below are exact for Saturday night/Sunday morning March 15. 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 full descriptions of each active meteor shower will continue next week when the moon becomes less of a nuisance to observers.

The table below presents a summary of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning but may be used all week.