July 26-30 Meteors

The past 2 nights has seen quite a bit of meteor activity. Last night, in particular, was the peak of the Southern Delta Aquariids (SDA). Though its peak rates are only a fraction of what major showers like the Perseids (PER ) and Geminids (GEM) produce, the SDA still accounted for nearly a third of all meteors detected by my camera last night. Also a larger percentage of last night’s meteors were bright with a few coming close to fireball status.

This time of year a number of other showers are very active in the Aquarius/Capricornus/Pegasus area. Though not as active as the SDA, consistent low levels of activity have been seen from the Alpha Capricornids (CAP) and the July Pegasids (JPE). Even the Piscis Austrinids (PAU) got in the act last night with 2 detections. The Southern Iota Aquariids (SIA) seem to be MIA so far.

Next month’s big shower, the Perseids (PER), are ramping up. Even 2 weeks out, they are producing 1-2 meteors per night for my camera. Their activity should continue to increase as we approach their August 12/13 peak.

Obs Date(UT)    Time   TOT SPO ANT PPS CAP JPE PAU PER SDA ERI MUL GDR
SAL 2014-07-30 05h 45m  25  11  1   0   1   1   2   1   7   1   -   0
SAL 2014-07-29 07h 30m  24  10  2   1   1   1   0   2   1   1   2   3
SAL 2014-07-28 00h 00m             Clouds/rain all night
SAL 2014-07-27 00h 00m             Clouds/rain all night
SAL 2014-07-26 05h 09m   8  5   0   0   0   0   0   1   2   0   0   0
                  also no ZED, SIA, ATR or BCA were seen over the 3 nights

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
PPS - Phi Piscids
CAP - Alpha Capricornids
JPE - July Pegasids
PAU - Piscis Austrinids
PER - Perseids
ZED - July Zeta Draconids
SDA - Southern Delta Aquariids
SIA - Southern Iota Aquariids
ERI - Eta Eridanids
MUL - Mu Lyrids
GDR - July Gamma Draconids
ATR - Alpha Triangulids
BCA - Beta Cassiopeiids

July 24-25 Meteors

The monsoon has been on hiatus here in Tucson and finally we had two relatively clear nights. There were still a few clouds and last night was very murky with lots of dust coming up from Sonora thanks to a strong Gulf of California surge. (If you’re interested, the Madweather blog is a great source for understanding the weather in southeastern Arizona.)

The Southern Delta Aquariids and Alpha Capricornids are the most active showers. A handful of meteors was also seen from the Perseids radiant though they might also be Psi Cassiopeiids as mention in the previous post.

The monsoon moisture has raced back into Tucson today so tonight will probably involve more battles with the weather.

 

Obs Date(UT)    Time   TOT SPO ANT PPS SCA CAP JPE PAU PER ZED SDA SIA ERI
SAL 2014-07-25 05h 45m  16  6   0   0   -   2   1   0   0   1   4   0   0
SAL 2014-07-24 07h 30m  19  9   0   0   2   3   0   0   3   1   0   0   1
                           also no MUL or GDR were seen over the 2 nights

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
PPS - Phi Piscids
SCA - Sigma Capricornids
CAP - Alpha Capricornids
JPE - July Pegasids
PAU - Piscis Austrinids
PER - Perseids
ZED - July Zeta Draconids
SDA - Southern Delta Aquariids
SIA - Southern Iota Aquariids
ERI - Eta Eridanids
MUL - Mu Lyrids
GDR - July Gamma Draconids

July 16-23 Meteors

Talk about a lot of active meteor showers. I had a hard time fitting all of the data in the table below.

Though the weather has still been poor in Tucson we did get a good clear night on July 22 (actually the night of July 21/22) with 24 meteors detected. That night also marked a change in my meteor camera system. I had to replace the outdoor housing because the old one was leaking badly. The change meant repointing the camera and reproducing an astrometric solution. I also took the opportunity to fiddle with the contrast and brightness of the video which should result in more meteors being detected.

The past week saw the start of two of the better showers of the summer, the Perseids (PER) and Southern Delta Aquariids (SDA). The Perseids should be known to most of you as one of the best annual showers. This year they peak on the night of August 12/13. Unfortunately the Moon will be very bright and will hinder any Perseid watching this year.

The other good shower are the Southern Delta Aquariids (SDA). This shower is one of the better showers for Southern Hemisphere observers but are still good for northerners too. The SDAs do not produce a lot of meteors, only ZHRs of 15-20 at their peak versus 60-120 for the Perseids. Still you may notice quite a few SDAs radiating from the area of Aquarius and Capricornus. The Alpha Capricornids (CAP), PAU (Piscis Austrinids) and SIA (Southern Iota Aquariids) are also active from the same region.

There has been some chatter on the meteorobs mailing list about a large number of Psi Cassiopeiids (PCA) detected by the Canadian Meteor Orbit Radar (CMOR). Surprisingly few of these meteors have been detected by visual and video observers. Over the past two nights perhaps 1 or 2 of my 34 detections have come from this shower. This suggests that these meteors are too faint for video (LM ~ +3) and visual (LM ~ +5) observers but not too faint for radar (LM ~ +8). The CMOR data also shows activity from the SDAs and CAPs.

equatorial

Plot of meteor radiants from the Canadian Meteor Orbit Radar (CMOR). The display is Earth-centric in RA/DEC space with opposition at 0 deg longitude and the Sun at 180 deg. Plot is from the ASGARD Web Log (http://fireballs.ndc.nasa.gov/).

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Obs Date(UT)    Time   TOT SPO ANT PPS SCA CAN CAP JPE PAU PER ODR ZED SDA SIA
SAL 2014-07-23 01h 10m  10  4   0   1   0   -   1   0   0   0   0   0   4   0
SAL 2014-07-22 08h 46m  24  16  1   1   0   -   2   0   0   1   0   1   1   1
SAL 2014-07-21 01h 17m  3   2   0   0   0   0   1   0   0   0   0   0   0   0
SAL 2014-07-20 06h 43m  4   3   0   0   1   0   0   0   0   0   0   0   -   -
SAL 2014-07-19 01h 10m  1   1   0   0   0   0   0   0   0   0   0   0   -   -
SAL 2014-07-18 05h 59m  9   5   0   0   1   0   1   0   0   2   0   -   -   -
SAL 2014-07-17 01h 12m  5   2   0   1   0   0   1   0   0   1   0   -   -   -
SAL 2014-07-16 01h 28m  10  4   1   1   1   1   1   1   0   -   -   -   -   -

SAL - SALSA3 camera in Tucson (Carl Hergenrother)
VIS - Visual observations from Tucson (Carl Hergenrother)
Time - Total amount of time each camera looked for meteors 
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelions
PPS - Phi Piscids
SCA - Sigma Capricornids
CAN - c Andromedids
CAP - Alpha Capricornids
JPE - July Pegasids
PAU - Piscis Austrinids
PER - Perseids
ODR - Omicron Draconids
ZED - July Zeta Draconids
SDA - Southern Delta Aquariids
SIA - Southern Iota Aquariids

Meteor Activity Outlook for August 4-10, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

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 12. This shower is active most of the month and remains above the level of the sporadic background for a week centered on August 12. 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 south of the equator, meteor rates are still decent but falling rapidly. The sporadic rates continue their downward slide and the Perseid radiant does not rise high into the sky as seen in the southern hemisphere so rates from this shower are greatly reduced when compared to the northern hemisphere.

During this period the moon reaches its last quarter phase on Thursday August 9th. This weekend the bright waning gibbous moon will rise during the late evening hours and will effectively ruin the sky for meteor watching the remainder of the night. The estimated total hourly rates for evening observers this week is near four for observers located in the northern hemisphere and two for observers south of the equator. For morning observers the estimated total hourly rates should be near fifteen for those located in the mid-northern hemisphere (45 N) and ten for those viewing from the mid-southern hemisphere (45 S). Locations between these two extremes would see activity between the listed figures. 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. Morning rates are reduced during this period due to the intense moonlight.

The list below presents a summary of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning August 4/5, but may be used all week. The full descriptions of each radiant will continue next week when the moon becomes less of a nuisance to observers.

Kappa Cygnids (KCG) – 18:06 (274) +46   Velocity 23km/sec
Northern Hemisphere – <1 per hr    Southern Hemisphere – <1 per hour

Alpha Capricornids (CAP) – 20:36 (309) -09   Velocity 25km/sec
Northern Hemisphere – 1 per hr    Southern Hemisphere – 1 per hour

Antihelions (ANT) – 21:40 (325) -12   Velocity 30km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – 1 per hour

Delta Aquariids (SDA) – 22:42 (346) -14   Velocity 42km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – 3 per hour

Piscids Austrinids (PAU) – 23:12 (348) -27   Velocity 35km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – 1 per hour

Perseids (PER) – 02:28 (037) +56   Velocity 61km/sec
Northern Hemisphere – 6 per hr   Southern Hemisphere – 3 per hour

Alpha Triangulids (ATR) – 02:40 (040) +37   Velocity 67km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Eta Eridanids (ERI) – 02:52 (043) -13   Velocity 64km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

Meteor Activity Outlook for July 28-August 3, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

Meteor season finally gets going in July for the northern hemisphere. The first half of the month will be much like June. 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 Delta Aquariids.

During this period the moon reaches its full phase on Wednesday August 1st. At this time the moon will be located opposite the sun and will be above the horizon all night long.This weekend the waxing gibbous moon will set during the late morning hours, allowing a short window of opportunity to view activity under dark skies. The estimated total hourly meteor rates for evening observers this week is near four no matter your location. For morning observers the estimated total hourly rates should be near twenty six from the mid-northern hemisphere and twenty eight from the mid-southern hemisphere. 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 due to moonlight.

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 28/29. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following radiants are expected to be active this week:

A new source found by the IMO video cameras to be active this time of year are the July Zeta Draconids (ZED). This radiant has been found to be active from July 19-29 with maximum activity activity occurring on the 19th. The last of these meteors may be seen this weekend from a radiant located at 18:06 (271) +62, which is situated in southern Draco, eight degrees southeast of the third magnitude star Al dhibain (Zeta Draconis). Due to a low amount of data the mean position of activity shifts quite a bit night to night so consider this a wide radiant until better parameters can be obtained. Current rates would most likely be less than one per hour no matter your location. The radiant is best placed near 2200 (10pm) LDT when it lie highest above the horizon. With an entry velocity of 23 km/sec., the average July Zeta Draconid meteor would be slow.

Another new source found by the IMO video cameras to be active this time of year is the July Gamma Draconids (GDR). This radiant has been found to be active from July 24-31, with maximum activity occurring on the 28th. Unfortunately the bright, waxing gibbous moon is above the horizon when this source is best placed in the sky. Therefore rates would most likely be less than one per hour no matter your location. The radiant is currently located at 18:42 (281) +51, which is locate six degrees east of the second magnitude star Eltanin (Gamma Draconis). The radiant is best placed near 2300 (11pm) LDT when it lie highest above the horizon. With an entry velocity of 27 km/sec., the average July Gamma Draconid meteor would be slow.

The Alpha Capricornids (CAP) are active from a wide radiant located at 20:18 (305) -11. This position lies in northwestern Capricornus, only one degree north of the third magnitude double star Alpha Capricornii. The radiant is best placed near 0100 local daylight time (LDT), when it lies on the meridian and is highest in the sky. Maximum activity is expected on the 29th so current rates should be near two per hour under dark skies. Don’t confuse these meteors with the antihelion meteors, which have a radiant just to the east. Both radiants need to be in your field of view to properly sort these meteors. With an entry velocity of 25 km/sec., most activity from this radiant would be slow, a bit slower than the antihelions. This radiant is well seen except for far northern latitudes where it remains twilight all night long and the radiant does not rise as high into their sky.

The large Antihelion (ANT) radiant is currently located at 21:12 (318) -14. This position lies on the Capricornus/Aquarius border, two degrees northwest of the fourth magnitude star Iota Capricorni. Due to the large size of this radiant, Antihelion activity may also appear from southern Aquila, Microscopium, eastern Sagittarius, Aquarius, and Piscis Austrinus as well as Capricornus. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Rates at this time are expected to be near one per hour as seen from the northern hemisphere and two per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

The Delta Aquariids (SDA) reach maximum activity on the 29th from a radiant located at 22:42 (340) -16. This position is located in southwestern Aquarius, three degrees west of the third magnitude Delta Aquarii. Hourly rates will depend on your latitude and time of night. Unfortunately the moon will be above the horizon when the radiant culminates near 0300 LDT. During the last hour of darkness rates should range from fifteen shower members as seen from the southern hemisphere to less than five as seen from high northern latitudes. With an entry velocity of 42 km/sec., most activity from this radiant would be of average velocities.

The Piscids Austrinids (PAU) are a minor shower not well seen from the northern hemisphere. This radiant is active from July 15 through August 10. Maximum activity occurs on July 28 when the zenith hourly rate (ZHR) may reach five. These rates are only seen from the southern hemisphere where the radiant passes overhead. From mid-northern latitudes, rates of one per hour at maximum are usually seen. The radiant is currently located at 22:48 (342) -29. This position lies in eastern Piscis Austrinus, three degrees southwest of the bright first magnitude star Fomalhaut (Alpha Piscis Austrinus). The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 35km/sec., most
activity from this radiant would be of average velocities.

The Perseids (PER) are active from a radiant located at 01:46 (027) +54. This position lies on the Cassiopeia/Perseus border, five degrees east of the fourth magnitude star Theta Cassiopeiae. The radiant is best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Since the maximum is not until August 12th, current rates would be only three to four per hour at best, as seen from the northern hemisphere. Activity from this source is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

Another new source found by the IMO video cameras to be active this time of year are the Alpha Triangulids (ATR). This radiant has recently been found to be active later than previously published, with the activity period ranging from July 25 through August 21 with maximum activity occurring on July 27. Current rates would be near one per hour as seen from the northern hemisphere and less than one from the southern hemisphere. The radiant is currently located at 02:02 (031) +40, which is actually situated in eastern Andromeda, three degrees south of the famous second magnitude star double star Almach (Gamma Andromedae). The radiant is best placed during the last hour before dawn, when it lies highest in a dark sky. With an entry velocity of 67 km/sec., the average Alpha Triangulid meteor would be swift.

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

The table below presents a condensed version of the expected activity this week.
Rates and positions are exact for Saturday night/Sunday morning .

July Zeta Draconids (ZED) – 18:06 (271) +62   Velocity 23km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

July Gamma Draconids (GDR) – 18:42 (281) +51   Velocity 27km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Alpha Capricornids (CAP) – 20:18 (305) -11   Velocity 25km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – 2 per hour

Antihelions (ANT) – 21:12 (318) -14   Velocity 30km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 2 per hour

Delta Aquariids (SDA) – 22:42 (340) -16   Velocity 42km/sec
Northern Hemisphere – 5 per hr   Southern Hemisphere – 12 per hour

Piscids Austrinids (PAU) – 22:48 (342) -29   Velocity 35km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 3 per hour

Perseids (PER) – 01:46 (027) +54   Velocity 61km/sec
Northern Hemisphere – 4 per hr   Southern Hemisphere – 2 per hour

Alpha Triangulids (ATR) – 02:02 (031) +40   Velocity 67km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

Meteor Activity Outlook for July 21-27, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

Meteor season finally gets going in July for the northern hemisphere. The first half of the month will be much like June. 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 Delta Aquariids.

During this period the moon reaches its first quarter phase on Wednesday the 25th. At this time the moon will be located ninety degrees east of the sun and set near midnight local daylight time (LDT). This weekend the waxing crescent moon will set during the late evening hours and will not hamper observing efforts during the more active morning hours. The estimated total hourly meteor rates for evening observers this week is near four no matter your location. For morning observers the estimated total hourly rates should be near sixteen from the mid-northern hemisphere and fourteen from the mid-southern hemisphere. 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.

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.

The following radiants are expected to be active this week:

A new source found by the IMO video cameras to be active this time of year are the July Zeta Draconids (ZED). This radiant has been found to be active from July 19-29. Maximum activity activity occurs on the 19th from a position of  17:23 (263) +61, which is situated in southern Draco, five degrees southeast of the third magnitude star Al dhibain (Zeta Draconis). Due to a low amount of data the mean position of activity shifts quite a bit night to night so consider this a wide radiant until better parameters can be obtained. Current rates would most likely be less than one per hour no matter your location. The radiant is best placed near 2200 (10pm) LDT when it lie highest above the horizon. With an entry velocity of 23 km/sec., the average July Zeta Draconid meteor would be slow.

The Alpha Capricornids (CAP) are active from a wide radiant located at 20:04 (301) -12. This position lies near the Sagittarius, Aquila, Capricornus border, three degrees west of the third magnitude double star Alpha Capricornii. The radiant is best placed near 0100 local daylight time (LDT), when it lies on the meridian and is highest in the sky. Current rates should be near one per hour no matter your location. Don’t confuse these meteors with the antihelion meteors, which have a radiant just to the east. Both radiants need to be in your field of view to properly sort these meteors. With an entry velocity of 25 km/sec., most activity from this radiant would be slow, a bit slower than the antihelions. This radiant is well seen except for far northern latitudes where it remains twilight all night long and the radiant does not rise as high into their sky.

The large Antihelion (ANT) radiant is currently located at 20:48 (312) -17. This position lies in central Capricornus, four degrees west of the fourth magnitude star Dorsum (Theta Capricorni). Due to the large size of this radiant, Antihelion activity may also appear from southern Aquila, Microscopium, eastern Sagittarius, northwestern Aquarius,  and western Piscis Austrinus as well as Capricornus. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Rates at this time are near their lowest of the year with one per hour no matter your location . With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

Activity from the Delta Aquariids (SDA) will begin this weekend from a radiant located at 22:18 (334) -18. This position is located in southwestern Aquarius, eight degrees southwest of the third magnitude Delta Aquarii. Maximum activity is expected on July 29th. Hourly rates will depend on your latitude. Those viewing from the southern tropics will see the best rates of near 1-2 per hour. Rates seen from mid-northern latitudes will range from 0-1 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 42 km/sec., most activity from this radiant would be of average velocities.

The Piscids Austrinids (PAU) are a minor shower not well seen from the northern hemisphere. This radiant is active from July 15 through August 10. Maximum activity occurs on July 28 when the zenith hourly rate (ZHR) may reach five. These rates are only seen from the southern hemisphere where the radiant passes overhead. From mid-northern latitudes, rates of one per hour at maximum are usually seen. The radiant is currently located at 22:23 (336) -32. This position lies in central Piscis Austrinus, eight degrees southwest of the bright first magnitude star Fomalhaut (Alpha Piscis Austrinus). The radiant is best placed near 0300 LDT, when it lies highest in the sky. With an entry velocity of 35km/sec., most activity from this radiant would be of average velocities.

The July Pegasids (JPE) are active with low rates during most of July with maximum activity occurring on the 10th. The radiant is currently located at 23:52 (358) +14. This area of the sky lies in southeastern Pegasus, four degrees west of the third magnitude star Algenib (Gamma Pegasi). This radiant is best placed during the last dark hour before dawn, when it lies highest above the horizon in a dark sky. Rates at this time should be less than one per hour no matter your location. With an entry velocity of 68 km/sec., the average July Pegasid meteor would be of swift speed.

The Perseids (PER) are active from a radiant located at 01:04 (016) +52. This position lies in southern Cassiopeia, six degrees southeast of the second magnitude star Shedar (Alpha Cassiopeiae). The radiant is best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Since the maximum is not until August 12th, current rates would be only two to three per hour at best, as seen from the northern hemisphere. Activity from this source is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

Another new source found by the IMO video cameras to be active this time of year is the Phi Piscids (PPS). This radiant has been found to be active from June 14 through July 30 with maximum activity occurring on July 1st. Current rates would most likely be less than one per hour no matter your location. The radiant is currently located at 01:56 (029) +36, which is situated on the Andromeda/Triangulum border, three degrees northwest of the third magnitude star Beta Triangulum. The radiant rises near midnight LDT but does not reach a sufficient altitude above the horizon until three hours later. Activity would best seen during the last dark hour of the morning when the radiant is located highest in a dark sky. With an entry velocity of 71 km/sec., the average Pi Piscid meteor would be swift.

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

The table below presents a condensed version of the expected activity this week.
Rates and positions are exact for Saturday night/Sunday morning .

July Zeta Draconids (ZED) – 17:23 (263) +61   Velocity 23km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Alpha Capricornids (CAP) – 20:04 (301) -12   Velocity 25km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Antihelions (ANT) – 20:48 (312) -17   Velocity 30km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Delta Aquariids (SDA) – 22:18 (334) -18   Velocity 42km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 2 per hour

July Pegasids (JPE) – 23:52 (358) +14   Velocity 68km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Perseids (PER) – 01:04 (016) +52   Velocity 61km/sec
Northern Hemisphere – 3 per hr   Southern Hemisphere – 1 per hour

Phi Piscids (PPS) – 01:56 (029) +36   Velocity 71km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

Meteor Activity Outlook for July 14-20, 2012

The following is a slightly edited version of Bob Lunsford’s excellent weekly summary of meteor activity. The original version can be found at the American Meteor Society’s site.

Meteor season finally gets going in July for the northern hemisphere. The first half of the month will be much like June. 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 Delta Aquariids.

During this period the moon reaches its new phase on Wednesday the 18th. At this time the moon will be located near the sun and will be invisible at night. This will be the best time of the month to try and view meteor activity as the bright moon will spoil the showers that peak near months end. This weekend the waning crescent moon will rise during the late morning hours and will not hamper observing efforts. The estimated total hourly meteor rates for evening observers this week is near four no matter your location. For morning observers the estimated total hourly rates should be near fourteen no matter your location. 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.

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 14/15. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following radiants are expected to be active this week:

The Alpha Capricornids (CAP) are active from a wide radiant located at 19:56 (297) -14. This position lies in northeastern Sagittarius, seven degrees west of the third magnitude double star Alpha Capricornii. The radiant is best placed near 0100 local daylight time (LDT), when it lies on the meridian and is highest in the sky. Current rates should be less than one per hour as seen from the northern hemisphere and near one per hour from the southern. Don’t confuse these meteors with the antihelion meteors, which have a radiant just to the east. Both radiants need to be in your field of view to properly sort these meteors. With an entry velocity of 25 km/sec., most activity from this radiant would be slow, a bit slower than the antihelions. This radiant is well seen except for far northern latitudes where it remains twilight all night long and the radiant does not rise as high into their sky.

The large Antihelion (ANT) radiant is currently located at 20:20 (305) -18. This position lies in western Capricornus, three degrees south of the third magnitude star Dabih (Beta Capricorni). Due to the large size of this radiant, Antihelion activity may also appear from southern Aquila, Microscopium, eastern Sagittarius, northwestern Aquarius, western Piscis Austrinus, and Scutum as well as Capricornus. This radiant is best placed near 0200 LDT, when it lies on the meridian and is located highest in the sky. Rates at this time are near their lowest of the year with less than one per hour as seen from the northern hemisphere and one per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

The Sigma Capricornids (SCA) are a new source of activity to look for this time of year. Actually this radiant has been listed before many years ago but had become lost in the many radiants active in this area of the sky this time of year. With over one million meteors available for analysis, the International Meteor Organization’s video section, led by Sirko Molau, has been able to isolate activity from this radiant. The radiant has been found to be active from June 19 through July 24 with maximum activity occurring on June 27. In early July it is still one of the most active radiants in the sky. Unfortunately that is not saying much as the strongest radiant only produces two meteors per hour this time of year. This radiant is now located at 21:12 (318) -03. This area of the sky is actually in western Aquarius, four degrees northwest of the third magnitude star Sadalsuud (Beta Aquarii). This radiant is best positioned for view on the meridian near 0300 LDT. With an entry velocity of 42 km/sec., the average Sigma Capricornid meteor would be of medium speed. Meteors from this source should be easy to distinguish from the slower Antihelion meteors as the two sources are separated by nearly twenty degrees. One must have both radiants within your field of view to properly distinguish between the two sources.

Another radiant returning to the list of active radiants are the July Pegasids (JPE). This source is active with low rates during most of July with maximum activity occurring on the 10th. The radiant is currently located at 23:28 (352) +12. This area of the sky lies in northern Pegasus, five degrees east of the third magnitude star Scheat (Beta Pegasi). This radiant is best placed during the last dark hour before dawn, when it lies highest above the horizon in a dark sky. Rates at this time should be near one per hour no matter your location. With an entry velocity of 68 km/sec., the average July Pegasid meteor would be of swift speed.

The Perseids (PER) are now active from a radiant located at 00:25 (006) +50. This position lies in southern Cassiopeia, seven degrees southwest of the second magnitude star Shedar (Alpha Cassiopeiae). The radiant is best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Since the maximum is not until August 12th, current rates would be only one to two per hour at best, as seen from the northern hemisphere. Activity from this source is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

Another new source found by the IMO video cameras to be active this time of year is the Phi Piscids (PPS). This radiant has been found to be active from June 14 through July 30 with maximum activity occurring on July 1st. During late June and early July this radiant is often the most active source of meteors in the sky with 1-2 shower members per hour during the early morning hours. The radiant is currently located at 01:30 (023) +31, which is situated on the Pisces/Triangulum border, four degrees northwest of the third magnitude star Ras al Muthallah (Alpha Triangulum). This position also happens to be very close to the large spiral galaxy M33. The radiant rises near midnight LDT but does not reach a sufficient altitude above the horizon until three hours later. Activity would best seen during the last dark hour of the morning when the radiant is located highest in a dark sky. With an entry velocity of 71 km/sec., the average Pi Piscid meteor would be swift.

Studies by Sirko Molau and Juergen Rendtel of the IMO’s video data has revealed an active radiant located in Andromeda this time of year. The c-Andromedids (CAN) are active from July 4-16, with maximum activity occurring on the 12th. The radiant position is currently located at 02:22 (035) +50. This area of the sky lies in extreme northeastern Andromeda, eight degrees north of the famous second magnitude double star Almach (Gamma Andromedae). This radiant is best placed during the last dark hour before dawn, when it lies highest above the horizon in a dark sky. Rates at this time should be less than one no matter your location. With an entry velocity of 59 km/sec., the average c-Andromedid meteor would be of swift speed.

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

The table below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning .

Alpha Capricornids (CAP) – 19:56 (297) -14   Velocity 25km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – 1 per hour

Antihelions (ANT) – 20:20 (305) -18   Velocity 30km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – 1 per hour

Sigma Capricornids (SCA) – 21:12 (318) -03   Velocity 42km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

July Pegasids (JPE) – 23:28 (352) +12   Velocity 68km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Perseids (PER) – 00:25 (006) +50   Velocity 61km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – <1 per hour

Phi Piscids (PPS) -01:30 (023) +31   Velocity 71km/sec
Northern Hemisphere – 2 per hr Southern Hemisphere – 1 per hour

c-Andromedids (CAN) – 02:22 (035) +50   Velocity 59km/sec
Northern Hemisphere – <1 per hr Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for August 7-13, 2010

The Meteor Activity Outlook is a weekly summary of expected meteor activity written by Robert Lunsford, Operations Manager of the American Meteor Society and contributor to this blog. The original unedited version of this week’s Meteor Activity Outlook can be found at the American Meteor Society’s site.

Meteor activity kicks into high gear in August as seen from the northern hemisphere. The main reason for this activity surge is the Perseid shower that peaks on August 13. This shower is active most of the month and remains above the level of the sporadic background for a week centered on August 13. The sporadic activity is also increasing as seen from the northern hemisphere and is now nearly double the rates from just three months ago. As seen from south of the equator, meteor rates are still decent but falling rapidly. The sporadic rates seen at the beginning of the month will be twice as high as those seen during the last days of the month. The Perseid radiant does not rise high into the sky as seen in the southern hemisphere so rates from this shower are greatly reduced when compared to the northern hemisphere.

During this period the moon reaches its new phase on Tuesday August 10th. At this time the moon will be located near the sun and is not visible at night. This weekend the waning crescent moon will not cause any trouble for morning observers. The estimated total hourly rates for evening observers this week is ~4 no matter your location. For morning observers the estimated total hourly rates should be ~24 from the northern hemisphere and ~21 as seen from the southern hemisphere. 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. During this period, moonlight reduces activity seen during the morning hours.

The radiant positions and rates listed below are exact for Saturday night/Sunday morning August 7/8. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following showers are expected to be active this week:

August Draconids (AUG)

Activity from the August Draconids (AUD) can be first detected near August 11th from a radiant located at 18:00 (270) +61. This position lies in southern Draco, close to the second magnitude star Eltanin (Gamma Draconis). Maximum activity is not predicted until August 21st so current rates would be low, <1 per night. With an entry velocity of 23 km/sec. most of these meteors will appear to move slowly. The radiant is best placed near 2200 Local Daylight Time (10pm LDT) when it lies highest in the sky. Due to its high northern declination this shower is not well seen from the southern hemisphere.

Kappa Cygnids (KCG)

The Kappa Cygnids (KCG) are active from a wide radiant located at 18:50 (282) +47. This position is further south than previous publications. It has been updated through the use of video observations by the International Meteor Organization. The new location lies on the Lyra/Draco border, eight degrees northwest of the brilliant star Vega (Alpha Lyrae). Maximum activity is now predicted to occur on August 14th. Current rates would be 1 per hour from the northern hemisphere and <1 shower member per hour from south of the equator. With an entry velocity of 23 km/sec. most of these meteors will appear to travel slower than average. The radiant is best placed near 2300 LDT (11pm LDT) when it lies nearly overhead for much of the Northern Hemisphere. Due to its high northern declination this activity is not well seen from the southern hemisphere.

Alpha Capricornids (CAP)

The Alpha Capricornids (CAP) are active from a wide radiant located at 20:45 (311) -07. This position lies in western Aquarius near the faint star 3 Aquarii. The radiant is best placed near 0100 local daylight time (LDT), when it lies on the meridian and is highest in the sky. Current rates should be ~1 per hour no matter your location. Don’t confuse these meteors with the antihelion meteors, which have a radiant just to the east. Both radiants need to be in your field of view to properly sort these meteors. With an entry velocity of 25 km/sec., most activity from this radiant would be slow, a bit slower than the antihelions. This radiant is well seen except for far northern latitudes where it remains twilight all night long and the radiant does not rise as high into their sky.

Antihelions (ANT)

The wide Antihelion (ANT) radiant is now centered at 21:52 (328) -11. This area of the sky lies in northeastern Capricornus, 4 degrees northeast of Deneb Algedi (Delta Capricornii). This radiant is best placed near 0200 local daylight time (LDT) when it lies on the meridian and is located highest in the sky. Due to the large size of this radiant, any meteor radiating from northwestern Piscis Austrinus, Microscopium, Capricornus, western Aquarius, or southeastern Aquila could be a candidate for this shower. Rates at this time should be ~2 per hour as seen from the northern hemisphere and ~3 per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of medium-slow speed.

Delta Aquariids (SDA)

The Delta Aquariids (SDA) reach maximum activity on Friday July 30th. The shower is still active from a radiant located at 23:12 (348) -14. This position lies in central Aquarius, 4 degrees northeast of the 3rd magnitude star Delta Aquarii. The radiant is best placed near 0300 LDT, when it lies highest in the sky. The optimal latitudes for viewing this shower lie in the southern tropics where the radiant passes overhead. With an entry velocity of 42 km/sec., most activity from this radiant would be of average velocities. Expect rates of 1 per hour north of the equator and 2 per hour from the southern hemisphere.

August Piscids (AUP)

A new shower discovered by Sirko Molau and Juergen Rendtel from the IMO’s video database are the August Piscids (AUP). This shower is only active on eight nights from August 2-9 with maximum activity occurring on the 4th. At maximum, the radiant is located at 00:44 (011) +19. This area of the sky is located in northern Pisces, 10 degrees north of the 4th magnitude star Delta Piscium. This radiant is best placed during the last hour before dawn when it lies highest in a dark sky. Hourly rates are expected to be <1. With an entry velocity of 66 km/sec., the average August Piscid meteor would be swift.

Perseids (PER)

The Perseids (PER) are active from a radiant located at 02:44 (041) +56. This position lies in northwestern Perseus very close to the 4th magnitude star Eta Persei. The radiant is best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Current rates would be ~5 per hour but this will swell to ~60 per hour at maximum activity on the mornings of the 12th and 13th. The latest predictions have the Earth encountering a trail of debris produced by comet 109P/Swift-Tuttle in the year 441 AD. This very old trail is not expected to produce an outburst but should enhance rates by 10-15 meteors per hour near 1200 Universal Time (05:00am PDT) on the 13th. Activity from the Perseids is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

Eridanids (ERI)

A second new shower discovered by Sirko Molau and Juergen Rendtel from the IMO’s video database are the Eridanids (ERI). This shower is active from August 4th through the 18th with maximum activity occurring on the 9th. Hourly rates could reach near two per hour at maximum. The radiant is currently located at 02:50 (042) -11. This area of the sky is located in extreme eastern Cetus about a dozen degrees south of Phycochroma (Delta Ceti). This radiant could account for the activity many observers have reported (including myself) this time of year from this portion of the sky. This radiant is best placed during the last hour before dawn when it lies highest in a dark sky. Hourly rates are expected to be <1. With an entry velocity of 64 km/sec., the average Eridanid meteor would be swift.

Beta Perseids (BPE)

Still another new shower discovered by Sirko Molau and Juergen Rendtel from the IMO’s video database are the Beta Perseids (BPE). This shower is active from August 4th through the 15th with maximum activity occurring on the 7th. Hourly rates are expected to remain low throughout this duration. The radiant is currently located at 03:02 (046) +40. This position lies only one degree southwest of the famous eclipsing variable star known as Algol (Beta Persei). This radiant has been suspected for many years and may have also been known as the Alpha-Beta Perseids. This radiant is best placed during the last hour before dawn when it lies highest in a dark sky. Hourly rates are expected to be <1. With an entry velocity of 67 km/sec., the average Beta Perseid meteor would be swift.

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

The list below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning.

Shower Name                RA     DEC   Vel     Rates
                                        km/s   NH    SH
AUG August Draconids     18h 00m  +61    23    <1    <1
KCG Kappa Cygnids        18h 50m  +47    23     1    <1
CAP Alpha Capricornids   20h 45m  -07    25     1     1
ANT Antihelions          21h 52m  -11    30     2     3
SDA Delta Aquariids      23h 12m  -14    42     1     2
AUP August Piscids       00h 44m  +19    66    <1    <1
PER Perseids             00h 44m  +51    61     3     2
ERI Eridanids            02h 50m  -11    64     2     2
BPE Beta Perseids        03h 02m  +40    67    <1    <1

RA - Right Ascension
DEC - Declination
Vel - Velocity relative to Earth (in km per sec)
Rates - Rate of visible meteors per hour from a
        dark site
NH - Northern Hemisphere
SH - Southern Hemisphere

July’s Meteors (plus the 1st 2 days of August)

July is usually one of the best month for meteor observing. This is especially true of the 2nd half of the month as many showers are active including 2 major ones, the Southern Delta Aquariids (SDA) and Perseids (PER). Unfortunately for me July is also the cloudiest month of the year due to our annual monsoon. This month was frustrating for 2 reasons. 1… except for a few days around the 4th, it was mostly cloudy every night resulting in very short clear windows for meteor watching. 2… even though it was cloudy almost every night and the rain was quite close by, it just never seemed to rain at my house until the very end of the month.

With the above in mind, the actually nightly numbers below are not a good measure of the amount of activity that is currently visible. One thing that is apparent from the table is the explosion in the number of active meteor showers as the month of July progressed. Many of these showers are minor and produce only a meteor or 2 per hour. Showers such as the aforementioned SDA and PER as well as the Alpha Capricornids (CAP) and Piscis Austrinids can produce up to 5-10 meteors per hour nightly.

August 1/2 was the last bad weather night. Starting on August 2/3 the monsoon takes a break and the nights are once again clear. This break in the monsoon action will be short lived (by Friday the rain/clouds should be back). The clear weather did give me a chance to test my new camera system which should result in even larger nightly meteor catches. More on that in the next post.

Obs  Date(UT)      Time    TOT SPO ANT CAN JPE CAP PAU PER SDA MUL ATR GDR ZDR
TUS  2010-08-02   01h19m    7   4   0   -   -   1   0   1   1   -   -   -   -
TUS  2010-08-01   00h18m    1   0   0   -   -   0   0   0   1   -   -   -   -
TUS  2010-07-28   00h19m    2   1   1   -   -   0   0   0   0   -   0   0   0
TUS  2010-07-25   00h39m    3   1   0   -   -   0   0   0   2   -   0   0   0
TUS  2010-07-24   02h58m    7   3   0   -   -   0   0   1   0   -   0   0   -
TUS  2010-07-21   02h59m    3   3   0   -   0   0   0   0   0   0   -   -   -
TUS  2010-07-18   00h30m    1   1   0   -   0   0   0   0   0   0   -   -   -
TUS  2010-07-17   02h12m    4   3   0   0   0   0   0   0   -   -   -   -   -
TUS  2010-07-13   02h29m    10  9   0   0   1   0   -   -   -   -   -   -   -
TUS  2010-07-12   01h59m    7   7   0   0   0   0   -   -   -   -   -   -   -
TUS  2010-07-10   00h19m    1   0   1   0   0   -   -   -   -   -   -   -   -
TUS  2010-07-09   01h17m    2   2   0   0   0   -   -   -   -   -   -   -   -
TUS  2010-07-08   00h16m    1   0   0   1   0   -   -   -   -   -   -   -   -
TUS  2010-07-07   05h53m    14  12  1   1   -   -   -   -   -   -   -   -   -
TUS  2010-07-06   07h55m    10  9   1   -   -   -   -   -   -   -   -   -   -
TUS  2010-07-05   07h54m    17  16  1   -   -   -   -   -   -   -   -   -   -
TUS  2010-07-04   07h53m    19  18  1   -   -   -   -   -   -   -   -   -   -
TUS  2010-07-03   01h34m    7   7   0   -   -   -   -   -   -   -   -   -   -
TUS  2010-07-02   05h44m    2   1   1   -   -   -   -   -   -   -   -   -   -
TUS  2010-07-01   07h31m    7   5   2   -   -   -   -   -   -   -   -   -   -

TUS - Camera in Tucson operated by Carl Hergenrother
SDG - Camera in San Diego operated by Bob Lunsford
TotTime - Total amount of time each camera looked for meteors
TOT - Total number of meteors detected
SPO - Sporadics (meteors not affiliated with any particular meteor shower)
ANT - Antihelion
CAN - c Andromedids
JPE - July Pegasids
CAP - Alpha Capricornids
PAU - Piscis Austrinids
PER - Perseids
SDA - Southern Delta Aquariids
MUL - Mu Lyrids
ATR - Alpha Triangulids
GDR - Gamma Draconids
ZDR - Zeta Draconids
AUP - August Piscids

Meteor Activity Outlook for July 31-August 6, 2010

[I have been very lax lately in my posting of Bob's weekly Meteor Activity Outlooks. I'm sorry for that. Here's this weeks installment and I'll try to keep up in future weeks.]

The Meteor Activity Outlook is a weekly summary of expected meteor activity written by Robert Lunsford, Operations Manager of the American Meteor Society and contributor to this blog. The original unedited version of this week’s Meteor Activity Outlook can be found at the American Meteor Society’s site.

After several months of low activity the meteor rates for both hemispheres see a marked increase in July. In the northern hemisphere the change is not noticeable until mid-month when several southern radiants, the Perseids, and sporadic rates all increase in activity. Southern rates are good all month long.

During this period the moon reaches its last quarter phase on Tuesday August 3rd. At this time the moon will be located 90 degrees west of the sun and will rise near 0100 local daylight time (LDT) for those located in the mid-northern latitudes. This weekend the waning gibbous moon will be in the sky most of the night making it difficult to view any meteor activity. As the moon passes its last quarter phase the situation improves as long as one observes with the the moon far from their field of view. The estimated total hourly rates for evening observers this week is ~4 no matter your location. For morning observers the estimated total hourly rates should be ~17 from the northern hemisphere and ~21 as seen from the southern hemisphere. 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. During this period, moonlight reduces activity seen during the morning hours.

The radiant positions and rates listed below are exact for Saturday night/Sunday morning July 31/August 1. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following showers are expected to be active this week:

Alpha Capricornids (CAP)

The Alpha Capricornids (CAP) are active from a wide radiant located at 20:30 (307) -09. This position lies in northwestern Capricornus, two degrees northeast of the third magnitude double star Alpha Capricornii. The radiant is best placed near 0100 local daylight time (LDT), when it lies on the meridian and is highest in the sky. Current rates should be ~2 per hour as seen from the northern hemisphere and ~3 per hour from the southern. Don’t confuse these meteors with the antihelion meteors, which have a radiant just to the east. Both radiants need to be in your field of view to properly sort these meteors. With an entry velocity of 25 km/sec., most activity from this radiant would be slow, a bit slower than the antihelions. This radiant is well seen except for far northern latitudes where it remains twilight all night long and the radiant does not rise as high into their sky.

Antihelions (ANT)

The wide Antihelion (ANT) radiant is now centered at 21:24 (321) -13. This area of the sky lies in northern Capricornus. The nearest bright star is fourth magnitude Iota Capricornii, which lies three degrees to the southwest. This radiant is best placed near 0200 local daylight time (LDT) when it lies on the meridian and is located highest in the sky. Due to the large size of this radiant, any meteor radiating from northwestern Piscis Austrinus, Microscopium, Capricornus, western Aquarius, or southeastern Aquila could be a candidate for this shower. Rates at this time should be ~2 per hour as seen from the northern hemisphere and ~3 per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of medium-slow speed.

Delta Aquariids (SDA)

The Delta Aquariids (SDA) reach maximum activity on Friday July 30th. Unfortunately the bright moon will obscure most of the activity from this shower. The radiant is located at 22:48 (342) -16. This position lies in southwestern Aquarius, just west of the third magnitude star Delta Aquarii. The radiant is best placed near 0300 LDT, when it lies highest in the sky. The optimal latitudes for viewing this shower lie in the southern tropics where the radiant passes overhead. With an entry velocity of 42 km/sec., most activity from this radiant would be of average velocities.

August Piscids (AUP)

A new shower discovered by Sirko Molau and Juergen Rendtel from the IMO’s video database are the August Piscids (AUP). This shower is only active on eight nights from August 2-9 with maximum activity occurring on the
4th. At maximum, the radiant is located at 00:30 (008) +18. This area of the sky is located in western Pisces, four degrees northwest of the third magnitude star Algenib (Gamma Pegasi). This position is also suspiciously close (15 degrees east) to the radiant of the 1970’s radiant known as the Upsilon Pegasids. Little has been reported of this radiant recently. This radiant is best placed during the last hour before dawn when it lies highest in a dark sky. Hourly rates are expected to be less than 1. With an entry velocity of 66 km/sec., the average August Piscid meteor would be swift.

Perseids (PER)

The Perseids (PER) are active from a radiant located at 02:03 (031) +55. This position lies in western Perseus, twelve degrees north of the famous second magnitude double star Almach (Gamma Andromedae). The radiant is
best placed during the last hour before the start of morning twilight when it lies highest in a dark sky. Current rates would be 2-3 per hour at best, as seen from the northern hemisphere. Activity from this source is not visible south of 40 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

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

The list below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning.

Shower Name                RA     DEC   Vel     Rates
                                        km/s   NH    SH
CAP Alpha Capricornids   20h 30m  -09    25     2     3
ANT Antihelions          21h 00m  -15    30     2     3
SDA Delta Aquariids      22h 48m  -16    42     3     5
AUP August Piscids       00h 30m  +18    66    <1    <1
PER Perseids             00h 44m  +51    61     3     2

RA - Right Ascension
DEC - Declination
Vel - Velocity relative to Earth (in km per sec)
Rates - Rate of visible meteors per hour from a
        dark site
NH - Northern Hemisphere
SH - Southern Hemisphere
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