Daniel Bush captured this fireball low in the northeastern sky at 04:33 UT (23:33 CDT) on June 3, 2022 (June 2nd local date), from Albany, Missouri USA. For more information on this fireball visit: https://fireball.amsmeteors.org/members/imo_view/event/2022/3253  ©Daniel Bush

Meteor activity kicks into high gear in August as seen from the northern hemisphere. The main reason for all this activity is the Perseid shower that peaks on August 13th. This shower is active most of the month and remains above the level of the sporadic background for a week centered on August 13th. The sporadic activity is also near maximum as seen from the northern hemisphere and is now more than double the rates from just three months ago. As seen from southern hemisphere, meteor rates are still decent but falling rapidly. The sporadic rates continue their downward slide plus the Perseid radiant does not rise high into the sky as seen in the southern hemisphere. Therefore, rates for the Perseids are greatly reduced when compared to those seen from the northern hemisphere.

During this period, the moon reaches its first quarter phase on Friday August 5th. At that time the moon is located 90 degrees east of the sun and sets near 23:30 Local Summer Time (LST) on August 4th. This weekend the waxing crescent moon will set during the early evening hours and will be long gone below the horizon, by the time the more active morning hours arrive. The estimated total hourly rates for evening observers this week should be near 4 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 25 as seen from mid-northern latitudes (45N) and 40 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. Evening rates are slightly reduced due to moonlight. 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 30/31. 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 kappa Cygnids (KCG) are active from August 3-28, with maximum occurring on the 17th. The radiant is currently located at 18:29 (277) +41. This area of the sky is located in northern Lyra, 3 degrees northwest of the zero magnitude star known as Vega (alpha Lyrae). To best see these meteors face low toward the north near 2300 LST when it lies on the meridian and is located highest in the sky. With a high northern declination, these meteors are difficult to view from the southern hemisphere. Expected hourly rates this week are less than 1 no matter your location. With an entry velocity of 23 km/sec., the average meteor from this source would be of slow velocity.

The last of the July gamma Draconids (GDR) are expected this weekend from a radiant located at 18:52 (283) +51. This area of the sky is located in southeastern Draco, 8 degrees east of the 2nd magnitude star known as Eltanin (gamma Draconis). The radiant also lies 12 degrees due north of the brilliant zero magnitude star Vega (alpha Lyrae). These meteors are not well seen from the Southern Hemisphere as the radiant does not rise very high in their northern sky. Observers concentrating on this activity should face low in the northern sky near 22:00 Local Standard Time (LST) to best view these meteors. With an entry velocity of 26 km/sec., the average gamma Draconid meteor would be of medium-slow velocity. In 2016, this stream produced a strong outburst that lasted approximately 1 hour. Nothing unusual has occurred since 2016. Some researchers feel these meteors are related to the kappa Cygnids, which are active in August. Normal rates for this shower is less than 1 shower member per hour no matter your location.

The alpha Capricornids (CAP) are active from July 7 through August 15, peaking on July 31st. The radiant is currently located at 20:32 (308) -10. This position lies in northwestern Capricornus, 3 degrees northeast of the naked eye double star known as (alpha Capricornii). Current rates are expected to be near 3 per hour as seen from the Northern Hemisphere and 4 per hour as seen from south of the equator. Observers concentrating on this activity should face high in the northern sky near midnight (LST) to best view these meteors. With an entry velocity of 22 km/sec., the average meteor from this source would be of slow velocity.

The large Anthelion (ANT) radiant is currently centered at 21:20 (320) -14. This position lies in north-central Capricornus, 3 degrees north of the 4th magnitude star known as iota Capricorni. This position is also just a few degrees northwest of the bright planet Saturn. 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. Observers concentrating on this activity should face high in the northern sky near 01:00 LST to best view these meteors. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.

The Southern delta Aquariids (SDA) are active from a radiant located at 22:42 (341) -16. This area of the sky is located in southwestern Aquarius, 2 degrees west of the 3rd magnitude star known as Skat (delta Aquarii). Hourly rates at this time should be near 10 as seen from the Northern Hemisphere and near 20 as seen from south of the equator. Observers concentrating on this activity should face high in the western sky near 02:00 LST to best view these meteors. With an entry velocity of 40 km/sec., the average meteor from this source would be of medium velocity.

The Piscids Austrinids (PAU) are an obscure shower, not well seen from the northern hemisphere. Recent studies by the IMO Video Network shows little activity. Other studies have indicated that this shower is active later than previously thought. The IMO Handbook states that this radiant is active from July 15th through August 10th, with maximum activity occurring on the July 28th. Using these parameters, the current position of the radiant would be 23:11 (341) -30. This area of the sky is located in near the border of Pisces Austrinus and Sculptor, just 2 degrees east of the 1st magnitude star known as Fomalhaut (alpha Piscis Austrini). To best see these meteors look high in the southern sky near 03:00 LST, when it lies highest in the sky. Current hourly rates should be less than 1 no matter your location. With an entry velocity of 43km/sec., most activity from this radiant would be of medium velocities.

The Perseids (PER) are active from a radiant located at 02:00 (030) +54. This position lies in northeastern Perseus, 8 degrees soutwest of the 4th magnitude star known as Miram (eta Persei A). Maximum is not until August 13th so current rates are expected to be near 5 per hour as seen from the Northern Hemisphere and 2 as seen from southern tropical locations. Observers concentrating on this activity should face half-way up in the northern sky during the last dark hour prior to dawn to best view these meteors. Observers in the northern hemisphere are better situated to view this activity as the radiant rises much higher in the sky before dawn compared to southern latitudes. With an entry velocity of 59 km/sec., the average meteor from this source would be of swift velocity.

The eta Eridanids (ERI) were discovered by the Tokyo Meteor Network back in 2001. The radiant is currently located near 02:23 (036) -15. This position lies in eastern Cetus, 4 degrees west of the 4th magnitude star known as pi Ceti. This source is active until September 10th, with maximum activity occurring on August 6th. Current rates would be near 1 per hour no matter your location. Observers concentrating on this activity should face high up in the eastern sky during the last dark hour prior to dawn to best view these meteors. With an entry velocity of 64 km/sec., the average meteor from this source would be of swift speed.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately 12 sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near 3 per hour. As seen from the tropical southern latitudes (25S), morning rates would be near 9 per hour as seen from rural observing sites and 3 per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are slightly reduced due to moonlight.

The list below offers the information from above in tabular form. Rates and positions are exact for Saturday night/Sunday morning except where noted in the shower descriptions.

 

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
kappa Cygnids (KCG) Aug 14 18:29 (277) +41 23 23:00 <1 – <1 II
July gamma Draconids (GDR) Jul 28 18:52 (283) +51 27 23:00 <1 – <1 II
alpha Capricornids (CAP) Jul 30 20:32 (308) -10 23 01:00 3 – 4 II
Anthelion (ANT) 21:20 (320) -14 30 02:00 2 – 3 II
Southern delta Aquariids (SDA) Jul 30 22:42 (341) -16 41 03:00  10 – 20 I
Piscids Austrinids (PAU) Jul 28 23:11 (341) -30 35 04:00 <1 – <1 II
Perseids (PER) Aug 13 02:00 (030) +54 59 06:00 5 – 2 I
eta Eridanids (ERI) Aug 06 02:23 (036) -15 64 07:00 <1 – <1 II

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