Meteor Activity Outlook for June 26-July 2, 2010

After several months of low activity the meteor rates for both hemispheres see a marked increase in July. In the northern hemisphere the change is not noticeable until mid-month when several southern radiants, the Perseids, and sporadic rates all increase in activity. Southern rates are good all month long. It should be noted that enhanced activity from the June Bootids is possible during this period. The maximum is expected near 0200 Universal Time on June 28th. This corresponds to 2200 or 10pm EDT on Sunday evening June 27th. The full moon will hinder observations but the June Bootids can be bright so it is suggested that you scan the skies as soon as it becomes dark on Saturday evening. The last outburst from this shower in 1998 lasted nearly 24 hours. These meteors are very slow and come from a radiant that lies nearly overhead for mid-northern observers at dusk.

During this period the moon reaches its full phase on Saturday June 26th. At this time the moon will be located opposite the sun and will remain in the sky all night long. Later next week a small window of opportunity exists for viewing in dark skies just after the end of evening twilight as the moon rises later in the evening. The estimated total hourly rates for evening observers this week is near one for northern observers and two for those viewing from south of the equator. For morning observers the estimated total hourly rates should be near three 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 intense moonlight.

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 June 26/27. 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 list 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.