During July observers in the northern hemisphere witness a surge in meteor activity, especially during the second half of the month. The source of this increase is increased sporadic rates along with several showers located opposite the sun. The Perseids also become active in mid-July with increasing rates as the Earth nears the August 12 maximum. During the first week of the month, observers south of the equator are enjoying some of their best rates of the year. This activity is produced by the strongest sporadic rates of the year and the fact that the Antihelion radiant is positioned well south of the celestial equator this time of year. During the second half of the month the sporadic rates begin to plummet and are the equal of rates seen in the northern hemisphere by the end of the month.
During this period the moon reaches its full phase on Tuesday July 11. This weekend and for the remainder of this period, the moon will be present in the sky most of the night, 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 two for those in the Northern Hemisphere and three 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 ten 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 full descriptions will continue in two weeks when the moon is not such a nuisance to observers.
Alpha Capricornids (CAP) 19:16 (289) -15
Northern Hemisphere 1 – Southern Hemisphere 1
Antihelion (ANT) – 19:56 (299) -20
Northern Hemisphere 1 – Southern Hemisphere 2
South Delta Aquarids (SDA) 21:36 (324) -19
Northern Hemisphere >1 – Southern Hemisphere >1
Clear Skies!