Martin Timpe captured this fireball with his AllSky7 Camera System at 21:27 UT (23:27 CEST) on April 15, 2022, from Hofheim am Taunus, Germany. For more information on this fireball visit: https://fireball.amsmeteors.org/members/imo_view/event/2022/2329 ©Martin Timpe

Meteor season finally gets going in July for the Northern Hemisphere. The first half of the month will be much like June with predominately slow rates. After the 15th though, both sporadic and shower rates increase significantly. For observers in the Southern Hemisphere, sporadic rates will be falling but the overall activity will increase with the arrival of the Southern delta Aquariids during the last week of the month.

During this period, the moon reaches its first quarter phase on Thursday July 7th. At that time the moon is located 90 degrees east of the sun and will set near 01:00 local summer time (LST). This weekend the waxing crescent moon will set during the evening hours and will not interfere with meteor observing during the more active morning hours. The estimated total hourly rates for evening observers this week should be near 3 as seen from mid-northern latitudes (45N) and 4 as seen from tropical southern locations (25S) For morning observers, the estimated total hourly rates should be near 9 as seen from mid-northern latitudes (45N) and 11 as seen from tropical southern locations (25S). 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 brighter 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 July 2/3. 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. I have also included charts of the sky that display the radiant positions for evening, midnight, and morning. The center of each chart is the sky directly overhead at the appropriate hour. These charts are oriented for facing south but can be used for any direction by rotating the charts to the desired direction. 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 sporadic. Meteor activity is not seen from radiants that are located far 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.

 

Radiant Positions at 23:00 LST

Radiant Positions at 23:00 Local Summer Time

Radiant Positions at 01:00 LST

Radiant Positions at 01:00 Local Summer Time

Radiant Positions at 03:00 LST

Radiant Positions at 03:00 Local Summer Time

These sources of meteoric activity are expected to be active this week.

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The alpha Capricornids (CAP) are active from July 3 through August 15, peaking on July 30th. The radiant is currently located at 18:56 (284) -17. This position lies in northern Sagittarius, 4 degrees north of the 4th magnitude star known as xi2 Sagittarii. Current rates are expected to be less than 1 per hour no matter your location. These meteors are best seen near 0100 local summer time (LST), when the radiant lies highest in the sky. With an entry velocity of 23 km/sec., the average meteor from this source would be of slow velocity.

The large Anthelion (ANT) is currently centered at 19:36 (294) -20. This position lies in eastern Sagittarius, 4 degrees northeast of the 3rd magnitude star known as Albaldah (pi Sagittarii). This radiant is best placed near 02:00 LST when it lies on the meridian and is highest in the sky. Rates at this time should be near 2 per hour as seen from the Northern Hemisphere and 3 as seen from south of the equator. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.

The July Pegasids (JPE) are active from July 4-14 with maximum activity occurring on July 10th. The radiant is currently located at 22:12 (333) +13. This area of the sky is located in southwestern Pegasus, 6 degrees northwest of the 3rd magnitude star known as Homam (zeta Pegasi). This radiant is best placed near 0500 LST, when it lies on the meridian and is located highest in the sky. Rates are expected to be less than 1 per hour this week no matter your location. With an entry velocity of 61 km/sec., the average meteor from this source would be of swift velocity.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately 7 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 2 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 8 per hour as seen from rural observing sites and 2 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.

 

SHOWER DATE OF MAXIMUM ACTIVITY CELESTIAL POSITION ENTRY VELOCITY CULMINATION HOURLY RATE CLASS
RA (RA in Deg.) DEC Km/Sec Local Summer Time North-South
alpha Capricornids (CAP) Jul 30 18:56 (284) -17 23 01:00 <1 – <1 II
Anthelion (ANT) 19:36 (294) -20 30 02:00 2 – 3 II
July Pegasids (JPE) Jul 10 22:12 (333) +13 61 05:00 <1 – <1 IV

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