Meteor Activity Outlook for July 21-27, 2018

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Jeff Sullivan captured this short fireball while photographing the Milky Way on July 7 at 23:06 PDT from Bodie, CA USA. For more of Jeff’s excellent work visit: www.JeffSullivanPhotography.com

During this period the moon will reach it’s full phase on Friday July 27th. At that time the moon will be located opposite the sun and will lie above the horizon most of the night. This weekend the waxing gibbous moon will set during the early morning hours allowing a few hours of dark skies in which to watch meteor activity under good conditions. The estimated total hourly meteor rates for evening observers this week is near 3 as seen from mid-northern latitudes and also 3 for those viewing from subtropical southern latitudes (25S). For morning observers the estimated total hourly rates should be near 17 for those viewing from mid-northern latitudes and also 17 for those viewing from subtropical southern latitudes (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 reduced during this period 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 21/22. 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 near 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 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 22:00 LDT

Radiant Positions at 22:00
Local Daylight Saving Time

Radiant Positions at 01:00 LDT

Radiant Positions at 0100
Local Daylight Saving Time

Radiant Positions at 4:00 LDT

Radiant Positions at 04:00
Local Daylight Saving Time

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

The July gamma Draconids (GDR) were first noticed by Japanese observers using SonotoCo and the IMO’s network team of Sirko Molau and Juergen Rendtel in 2009. This stream is active from July 22-30 with maximum activity occurring on July 28. The radiant is currently located at 18:28 (277) +50, which places it in southeastern Draco, 4 degrees southeast 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). This radiant is best placed near midnight local daylight saving time (LDT), when it lies on the meridian and is located highest in the sky. With an entry velocity of 28 km/sec., the average gamma Draconid meteor would be of slow velocity. In 2016, this stream produced an strong outburst that lasted approximately 1 hour. If a repeat performance occurs this year it will most likely occur near 12:00 Universal Time on July 28, which is equivalent to 5:00am PDT. This timing favors the west coast of North America and the Pacific area. Nothing unusual occurred in 2017. Some researchers feel these meteors are related to the kappa Cygnids, which are active next month.

The alpha Capricornids (CAP) are active from July 3 through August 11 with maximum activity occurring during the last week of July. The broad maximum occurs anywhere from July 25 to the 30th with visual rates usually around 3 per hour. The radiant is currently located at 19:52 (298) -11, which places it in southern Aquila, 5 degrees northwest of the 4th magnitude star known as alpha 2 Capricornii. This radiant is best placed near 0100 LDT, when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 2 no matter your location. With an entry velocity of 22 km/sec., the average alpha Cap meteor would be of slow velocity.

The center of the large Anthelion (ANT) radiant is currently located at 20:48 (312) -18. This position lies in central Capricornus, 3 degrees west of the 4th magnitude Dorsum (theta Capricornii). This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 1 as seen from mid-northern latitudes and 2 as seen from tropical southern latitudes. With an entry velocity of 30 km/sec., the average Anthelion meteor would be of slow velocity.

The Northern delta Aquariids (NDA) are active from July 23 through August 27. The radiant is currently located at 21:44 (326) -07. This position is located in western Aquarius, 3 degrees east of the 3rd magnitude star known as Sadalsuud (beta Aquarii). Maximum activity is not expected until August 14, so hourly rates will low at this time. The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 38 km/sec., these meteors would be of medium velocities. This shower seems to be a continuation of the Northern June Aquilids, which has been active since early June.

The Southern Delta Aquariids (SDA) are now active from a radiant located at 22:12 (333) -19. This position is located in southwestern Aquarius, 10 degrees southwest of the 3rd magnitude star known as Skat (delta Aquarii). Maximum activity is expected on July 30th. Hourly rates will depend on your latitude. Those viewing from the southern tropics will see the best rates of near 2-3 per hour. Rates seen from mid-northern latitudes will range from 1-2 per hour, depending on the haziness of your skies. The radiant rises near 2200 (10pm) LDT for observers located in the mid northern latitudes, but is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 41 km/sec., most activity from this radiant would be of average velocities.

The last of the epsilon Pegasids (EPG) are expected this weekend. These meteors are active from July 03-23 with maximum activity occurring on July 11th. The radiant position currently lies at 22:40 (340) +17. This area of the sky lies in western Pegasus, 4 degrees northwest of the 2nd magnitude star known as Markab (alpha Pegasi). These meteors are best seen near 0400 LDT when the radiant lies highest in the sky. Hourly rates are expected to be less than 1 no matter your location. With an entry velocity of 28 kilometers per second, a majority of these meteors will appear to move slowly.

The July Pegasids (JPE) have been noticed for some time now but have had a checkered history. It has been added, dropped, and then re-added to several radiant lists. Video studies within the past 10 years has positively identified this source as an active radiant during the entire month of July. Maximum activity occurred on July 10th. The radiant is currently located at 23:51 (358) +14. This area of the sky is located in southern Pegasus, 4 degrees west of the 3rd magnitude star known as Algenib (gamma Pegasi). This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Rates are expected to be less than 1 per hour this week no matter your location. With an entry velocity of 68 km/sec., the average meteor from this source would be of swift velocity.

The Perseids (PER) are active from a radiant located at 01:06 (016) +52. This position is not is Perseus, rather it lies in southern Cassiopeia, 6 degrees southeast of the 2nd magnitude star known as Schedar (alpha Cassiopeiae). This area of the sky is best placed for viewing during the last dark hour before dawn when it lies highest in the sky. Maximum is not until August 13 so current rates are expected to be near 2 per hour as seen from the northern hemisphere and 1 as seen from south of the equator. Unfortunately these meteors are not well seen from the southern hemisphere. With an entry velocity of 59 km/sec., the average meteor from this source would be of swift velocity.

The 49 Andromedids (FAN) were discovered by Željko Andreić and the Croatian Meteor Network team based on studying SonotaCo and CMN observations (SonotaCo 2007-2011, CMN 2007-2010). These meteors are active from July 6 through August 14 with maximum activity occurring on July 21. The current position of the radiant is 01:44 (026) +49. This position lies in extreme northeastern Andromeda, very close to the 4th magnitude star known as Nembus (51 Andromedae). Rates are currently expected to be less than 1 per hour no matter your location. With an entry velocity of 60 km/sec., the average meteor from this source would be of swift speed.

The eta Eridanids (ERI) were discovered by Japanese observers back in 2001. Activity from this stream is seen from July 23 though September 17 with maximum activity occurring on August 11. The radiant currently lies at 01:48 (027) -18, which places it in southern Cetus, 2 degrees southeast of the 4th magnitude star known as tau Ceti. This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be less than 1 per hour during this period no matter your location. With an entry velocity of 65 km/sec., the average meteor from this source would be of swift velocity.

The psi Cassiopeiids (PCA) were discovered by Zdenek Sekanina in his study study of radio streams. These meteors are active from July 5 through August 7 with maximum activity occurring on July 22. The current position of the radiant is 02:20 (035) +73. This position lies in northeastern Cassiopeia, 2 degrees northeast of the 4th magnitude star known as 50 Cassiopeiae. Rates are  expected to be near 1 per hour as seen from the northern hemisphere and less than 1 as seen from south of the equator. With an entry velocity of 60 km/sec., the average psi Cassiopeiid meteor would be of swift speed.

The phi Piscids (PPS) are another discovery by Dr. Peter Brown and associates using data from the Canadian Meteor Orbit Radar (CMOR) installation. These meteors are active from June 8-August 02 with maximum activity occurring on July 5th. The radiant position currently lies at 02:16 (034) +32. This area of the sky lies in the small constellation of Triangulum, 2 degrees southwest of the 4th magnitude star known as gamma Trianguli. These meteors are best seen near during the last dark hour of the night when the radiant lies highest in a dark sky. Hourly rates are expected to be less than 1 no matter your location. With an entry velocity of 67 kilometers per second, a majority of these meteors will appear to move with swift velocities.

The last of the c-Andromedids (CAN) should be seen this week. Activity from this source is seen from June 26 though July 27 with maximum activity occurring on July 9. The radiant currently lies at 02:52 (043) +52, which places it in northwestern Perseus, just south of the 4th magnitude star known as tau Persei. This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. 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. Current rates less than 1 no matter your location. With an entry velocity of 58 km/sec., the average meteor from this source would be of swift velocity.

The July chi Arietids (JXA) were discovered by two investigating teams in Europe using video data from European video Meteor Network Database (EDMOND), SonotaCo, 2013; and CMN, 2013. Activity from this stream is seen from July 2 though August 1 with maximum activity occurring on July 13. The radiant currently lies at 02:56 (044) +12, which places it in southern Aries, 3 degrees northeast of the 4th magnitude star known as mu Ceti. This area of the sky is best seen during the last dark hour before dawn when the radiant lies highest in a dark sky. Current rates are expected to be less than 1 per hour no matter your location. With an entry velocity of 69 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 10 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 also be near 9 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 Daylight Saving Time North-South
July gamma Draconids (GDR) Jul 28 18:28 (277) +50 28 00:00 <1 – <1 IV
alpha Capricornids (CAP) Jul 27 19:52 (298) -11 22 01:00 2 – 2 II
Anthelions (ANT) 20:48 (312) -18 30 02:00 1 – 2 III
Northern delta Aquariids (NDA) Aug 14 21:44 (326) -07 38 03:00 <1 – <1 IV
Southern Delta Aquariids (SDA) Jul 30 22:12 (333) -19 41 04:00 2 – 3 I
epsilon Pegasids (EPG) Jul 11 22:40 (340) +17 28 05:00 <1 – <1 IV
July Pegasids (JPE) Jul 10 23:51 (358) +14 68 06:00 <1 – <1 IV
Perseids (PER) Aug 13 01:06 (016) +52 59 06:00 2 – 1 I
49 Andromedids (FAN) Jul 21 01:44 (026) +49 60 07:00 <1 – <1 IV
eta Eridanids (ERI) Aug 11 01:48 (027) -18 65 07:00 <1 – <1 IV
phi Piscids (PPS) Jul 05 02:16 (034) +32 66 08:00 <1 – <1 IV
psi Cassiopeiids (PCA) Jul 22 02:20 (035) +73 42 08:00 <1 – <1 IV
c-Andromedids (CAN) Jul 09 02:52 (043) +52 58 08:00 <1 – <1 IV
July chi Arietids (JXA) Jul 13 02:56 (044) +12 69 08:00 <1 – <1 IV

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3 comments

  • L 5 months ago

    I saw about 4 last night in Southern California from 10pm to 2 am PST. Absolutely beautiful!

    Reply to L
  • Russ 5 months ago

    Saw a Beautiful Green Burst last night driving back to Salem. It came in pretty low and was able to watch the whole thing fall apart to nothing, 3-5 seconds. so awesome!

    Reply to Russ

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