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During this period the moon reaches its new phase on Thursday August 1st. On that date the moon is located near the sun and is not visible at night. This weekend the waning crescent moon will rise during the early morning hours and will not interfere with viewing meteor activity as long as you keep it out of your field of view. The estimated total hourly meteor rates for evening observers this week is near 4 for those viewing from the southern hemisphere and 4 for those located north of the equator. For morning observers the estimated total hourly rates should be near 17 as seen from mid-northern latitudes (45N) and 14 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 brightest 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 27/28. 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.
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 18:40 (280) +50, which places it in southeastern Draco, 7 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 23:00 local standard time (LST), 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 medium-slow velocity. In 2016, this stream produced a strong outburst that lasted approximately 1 hour. If a repeat performance occurs this year it will most likely occur near 18:00 Universal Time on July 28. Nothing unusual occurred in 2017 and 2018. 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 20:10 (303) -10, which places it in northwestern Capricornus, 3 degrees northwest of the naked eye double star known Algedi (alpha Capricorni). This radiant is best placed near midnight (LST), when it lies on the meridian and is located highest in the sky. Hourly rates at this time should be near 2 for observers from mid-northern latitudes (45 N) and 3 as seen the southern tropics (S 25). 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 21:08 (317) -16. This position lies in central Capricornus, only 1 degree northeast of the 4th magnitude star known as Dorsum (theta Capricorni). Due to the large size of this radiant, anthelion activity may also appear from western Aquarius as well as Capricornus. This radiant is best placed near 0100 (LST), when it lies on the meridian and is located highest in the sky. Rates at this time should be near 2 per hour as seen from mid-northern latitudes (45 N) and 3 per hour as seen from southern tropics (S 25). 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 22:07 (332) -04. This position is located in northern Aquarius, 4 degrees south of the 3rd magnitude star known as Sadalmelik (alpha Aquarii). Maximum activity is not expected until August 14, so hourly rates will low at this time. The radiant is best placed near 0200 LST, 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 had been active since early June.

The Southern Delta Aquariids (SDA) are active from a radiant located at 22:34 (339) -17. This position is located in southwestern Aquarius, 4 degrees southwest of the 3rd magnitude star known as Skat (delta Aquarii). Maximum activity is expected on July 30th. Current (July 28th) hourly rates will depend on your latitude. Those viewing from the southern tropics will see the best rates of near 15 per hour. Rates seen from mid-northern latitudes will range from 5-10 per hour, depending on the haziness of your skies. The radiant rises near 21:00 LST for observers located in the southern tropics, but is best placed near 0200 LST, 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 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. We will go along with that idea until more information is available. It is now thought that this radiant is active from July 31 through August 19, with maximum activity occurring on the 9th. Using these parameters, the current position of the radiant would be 22:52 (343) -25. This area of the sky is located in northeastern Piscis Austrinus, 4 degrees north of the bright 1st magnitude star known as Fomalhaut (alpha Piscis Austrini). The radiant is best placed near 0300 LST, when it lies highest in the sky. Current rates would most likely be less than 1 per hour, no matter your location. With an entry velocity of 44km/sec., most activity from this radiant would be of average velocities.

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 have positively identified this source as an active radiant during the entire month of July. Maximum activity occurs on July 10th. The radiant is currently located at 00:11 (003) +15. This area of the sky is located in southern Pegasus, 2 degrees west of the 3rd magnitude star known as Algenib (gamma Pegasi). This radiant is best placed near 0400 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 68 km/sec., the average meteor from this source would be of swift velocity.

The Perseids (PER) are active from a radiant located at 01:40 (025) +54. This position lies in extreme western Perseus, 10 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 3 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 eta Eridanids (ERI) were discovered by Japanese observers back in 2001. Activity from this stream is seen from July 23 through September 17 with maximum activity occurring on August 11. The radiant currently lies at 02:04 (032) -17, which places it in southern Cetus, 4 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 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 02:11 (033) +51. This position lies in extreme northeastern Andromeda, 5 degrees northeast of the 4th magnitude star known as 51 Andromedae.. Rates are currently expected to be near 1 per hour as seen from the northern hemisphere and less than 1 as seen from the southern hemisphere. With an entry velocity of 60 km/sec., the average meteor from this source would be of swift speed.

The phi Piscids (PPS) were discovered 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 02:37 (039) +34. This area of the sky lies in eastern Triangulum, 3 degrees east of the 4th magnitude star known as gamma Trianguili. These meteors are best seen near during the last dark hour of the night when the radiant lies highest in a dark sky. Current hourly rates should 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 psi Cassiopeiids (PCA) were discovered by Zdenek Sekanina in his 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 03:00 (045) +75. This position lies in northeastern Cassiopeia, 5 degrees northeast of the faint star known as 50 Cassiopeiae. Hourly rates are currently 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 42 km/sec., the average psi Cassiopeiid meteor would be of medium speed.

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 through August 1 with maximum activity occurring on July 13. The radiant currently lies at 03:20 (050) +13, which places it in southeastern Aries, 2 degrees west of the 4th magnitude star known as 5 Tauri. 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 near 1 per hour during this period, 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 mid-northern hemisphere (45N), morning rates would be near 9 per hour as seen from rural observing sites and 4 per hour during the evening hours as seen from rural observing sites. As seen from the tropical southern latitudes (25S), one would expect to see approximately 8 sporadic meteors per hour during the last hour before dawn. Evening rates would be near 3 per hour. Locations between these two extremes would see activity between the listed figures.

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
gamma Draconids (GDR) Jul 28 18:40 (280) +50 28 00:00 <1 - <1 II
alpha Capricornids (CAP) Jul 27 20:10 (303) -10 22 01:00 2 - 3 II
Anthelion (ANT) - 21:08 (317) -16 30 02:00 2 - 3 II
Northern delta Aquariids (NDA) Aug 14 22:07 (332) -04 38 03:00 <1 - <1 IV
Southern Delta Aquariids (SDA) Jul 30 22:34 (339) -17 41 03:00 5 - 15 I
Piscids Austrinids (PAU) Aug 09 22:52 (343) -25 44 04:00 <1 - <1 II
July Pegasids (JPE) Jul 10 00:11 (003) +15 68 05:00 1 - 1 IV
Perseids (PER) Aug 13 01:40 (025) +54 59 06:00 3 - 1 I
eta Eridanids (ERI) Aug 11 02:04 (032) -17 67 07:00 <1 - <1 IV
49 Andromedids (FAN) Jul 21 02:11 (033) +51 60 07:00 1 - <1 IV
phi Piscids (PPS) Jul 05 02:37 (039) +34 67 07:00 <1 - <1 IV
psi Cassiopeiids (PCA) Jul 22 03:00 (045) +75 42 07:00 1 - <1 IV
July chi Arietids (JXA) Jul 13 03:20 (050) +13 69 08:00 1 - 1
Zgodnie z:
Robert Lunsford


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