Meteor Activity Outlook for August 25-31, 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 full phase on Friday August 31st. 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 early morning hours, allowing a few hours of dark skies between moon set and the start of morning twilight in which good activity can be observed. The estimated total hourly meteor rates for evening observers this week is near four for observers located at mid-northern latitudes and three for observers in mid-southern latitudes. For morning observers the estimated total hourly rates should be near twenty from the mid-northern hemisphere and 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 during this period 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 August 25/26. 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 Kappa Cygnids (KCG) are winding down but still active from a wide radiant located at 18:28 (268) +63. This position lies in a remote area of southern Draco. The nearest bright star is third magnitude Aldib (Delta Draconis), which lies seven degrees to the northeast. Some readers will notice that this position is west of that given last week. The reason for this seemingly retrograde motion is the different sub-centers of activity that appear within the large radiant area during this month. Observers need not be strict with shower association for this shower due to the wide radiant and these sub-centers of activity. Maximum activity occurred on August 18th so current rates would be less than one per hour no matter your location. 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 Local Daylight Time (LDT) 11pm Local Daylight Time (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.

The large Antihelion (ANT) radiant is currently located at 23:00 (345) -05. This position lies in northeastern Aquarius, four degrees northwest of the fourth magnitude star Phi Aquarii. Due to the large size of this radiant, Antihelion activity may also appear from eastern Capricornus, southern Pisces, southern Pegasus, and western Cetus as well as Aquarius. 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 no matter your location. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

There is an active yet unnamed radiant located just east of the “circlet” of Pisces this week. The exact location for Sunday morning is 23:48 (357) +06. This lies in western Pisces between the fourth magnitude stars Omega and Iota Piscium. Radiant drift per day averages 0.8 degree in right ascension and +0.4 in declination. This radiant is stronger than all but the Perseids so naked eye verification should be fairly easy. This activity is present from August 6th through September 6th with a maximum occurring on August 17th. With an entry velocity of 41 km/sec., most activity from this radiant would be of average velocities.

There is another active yet unnamed radiant located in southern Perseus active only this weekend The exact location for Sunday morning is 03:52 (058) +36. This position lies two degrees west of the fourth magnitude star Xi Persei. This is the fourth most active radiant in the sky so rates would be near one per hour as seen during the morning hours from the mid-northern hemisphere. This radiant is not well placed for viewing south of the equator. With an entry velocity of 69 km/sec., most activity from this radiant would appear as swift meteors.

The Perseids (PER) peaked on Sunday August 12th, producing visible hourly rates near 50 as seen from dark skies. They are still the most active radiant in the sky but rates are now down to only 2-3 shower members per hour as seen from the mid-northern hemisphere during the early morning hours. The current radiant is located at 04:28 (067) +59. This position lies in a blank portion of southern Camelopardlis, five degrees southeast of fourth magnitude star Beta Camelopardalis. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

The Aurigids (AUR) become active on August 25th but are very weak until the morning of August 30th. Maximum occurs on August 31st when it becomes the most active radiant in the sky. Unfortunately the full moon will spoil the display at this time so only 1-2 shower members will be visible per hour as seen during the morning hours from mid-northern latitudes. Very little activity would be visible from the southern hemisphere. At maximum the radiant is located at 06:02 (091) +39, which places it in eastern Auriga just two degrees north of third magnitude Theta Aurigae. With an entry velocity of 67 km/sec., most activity from this radiant would be swift.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately fourteen 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 five per hour as seen from rural observing sites and two per hour during the evening hours. Locations between these two extremes would see activity between the listed figures. Evening rates are reduced due to to moonlight during this period.

The list below presents a summary of the expected activity this week. Rates and
positions are exact for Saturday night/Sunday morning August 25/26, but may be
used all week.

Kappa Cygnids (KCG) – 18:28 (268) +63   Velocity 23km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Antihelions (ANT) – 23:00 (345) -05   Velocity 30km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Unnamed (UNK) – 23:48 (357) +06   Velocity 41km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Unnamed (UNK) – 03:52 (058) +36   Velocity 69km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – <1 per hour

Perseids (PER) – 04:28 (067) +59   Velocity 61km/sec
Northern Hemisphere – 3 per hr    Southern Hemisphere – 1 per hour

Aurigids (AUR) – 06:02 (091) +39   Velocity 67km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for August 18-24, 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 first quarter phase on Friday August 24th. At this time the moon will be located ninety degrees east of the sun and will set near midnight local daylight time (LDT). This weekend the waxing crescent moon will set during the early evening hours and will not interfere with meteor observing during the more productive morning hours. The estimated total hourly meteor rates for evening observers this week is near four for observers located at mid-northern latitudes and three for observers in mid-southern latitudes. For morning observers the estimated total hourly rates should be near twenty two from the mid-northern hemisphere and twelve 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 August 18/19. 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 Kappa Cygnids (KCG) are active from a wide radiant located at 18:28 (277) +59. This position lies in Draco, ten degrees northeast of the second magnitude star Eltanin (Gamma Draconis). Some readers will notice that this position is west of that given last week. The reason for this seemingly retrograde motion is the different sub-centers of activity that appear within the large radiant area during this month. Observers need not be strict with shower association for this shower due to the wide radiant and these sub-centers of activity. Maximum activity occurs on August 18th so current rates would be near two per hour from the northern hemisphere and less than one 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 Local Daylight Time (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.

The large Antihelion (ANT) radiant is currently located at 22:36 (339) -07. This position lies in central Aquarius, four degrees northeast of the fourth magnitude star Sadalsuud Sadalsuud (Beta Aquarii). Due to the large size of this radiant, Antihelion activity may also appear from eastern Capricornus, western Pisces, and southern Pegasus, western Cetus as well as Aquarius. 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 two per hour no matter your location. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

There is an active yet unnamed radiant located within the “circlet” of Pisces this week. The exact location for Sunday morning is 23:27 (352) +04. Radiant drift per day averages 0.8 degree in right ascension and +0.4 in declination. This radiant is stronger than all but the Perseids and the Antihelons so naked eye verification should be fairly easy. This activity is present from August 6th through September 6th with a maximum occurring on August 17th. With an entry velocity of 41 km/sec., most activity from this radiant would be of average velocities.

The Delta Aquariids (SDA) are near the end of their activity for 2012. They are still weakly active from a radiant located at 23:54 (359) -11. This position is located on the Aquarius/Cetus border, four degrees northeast of the Omega 2 Aquarii. Current hourly rates would be less than one no matter your location. The radiant 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.

There is another active yet unnamed radiant located close to Almach (Gamma Andromedae) this week. The exact location for Sunday morning is 02:04 (031) +41. Radiant drift averages 0.7 degree in right ascension and -0.3 in declination per day. This radiant is probably the weakest of all listed this week, yet with careful monitoring, several of these meteors should be visible each night . This activity is present from August 18th through the 25th with the maximum occurring on the 25th. With an entry velocity of 69 km/sec., most activity from this radiant would appear as swift meteors.

The Perseids (PER) peaked on Sunday August 12th, producing visible hourly rates near 50 as seen from dark skies. They are still weakly active from a radiant located at 03:47 (057) +59. This position lies in southwestern Camelopardlis, ten degrees northeast of the second magnitude star Mirfak (Alpha Persei). Current rates would be near five per hour from the  northern hemisphere and two per hour as seen from south of the equator. With an entry velocity of 61 km/sec., most activity from this radiant would be swift.

A 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 less than one per hour, no matter your location. The radiant is currently located at 03:44 (056) +38, which is actually situated in southern Perseus, four degrees southwest of Epsilon Persei. 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 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 five per hour as seen from rural observing sites and two per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.

The list below presents a summary of the expected activity this week. Rates and
positions are exact for Saturday night/Sunday morning August 11/12, but may be
used all week.

Kappa Cygnids (KCG) – 18:28 (277) +59   Velocity 23km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – <1 per hour

Antihelions (ANT) – 22:36 (339) -07   Velocity 30km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – 2 per hour

23:27 (352) +04   Velocity 41km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – 2 per hour

Delta Aquariids (SDA) – 23:54 (359) -11   Velocity 42km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

02:04 (031) +41   Velocity 67km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Perseids (PER) – 03:47 (057) +59   Velocity 61km/sec
Northern Hemisphere – 5 per hr   Southern Hemisphere – 2 per hour

Alpha Triangulids (ATR) – 03:16 (049) +37   Velocity 67km/sec
Northern Hemisphere – <1 per hr   Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

 

Meteor Activity Outlook for August 11-17, 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 new phase on Friday August 17th. At this time the moon will be located near the sun and will not be visible at night. This weekend the waning crescent moon will rise during the early morning hours, giving off some glare in the eastern sky. You can compensate for this by facing away from the moon in another direction where the sky should be largely unspoiled by moonlight. The estimated total hourly meteor rates for evening observers this week is near six for observers located at mid-northern latitudes and three for observers in mid-southern latitudes. For morning observers the estimated total hourly rates should be near sixty from the mid-northern hemisphere and twenty 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. Morning rates are slightly 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 August 11/12. 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 Kappa Cygnids (KCG) are active from a wide radiant located at 19:00 (285) +51. This position lies on the Cygnus/Draco border, eight degrees northwest of the third magnitude star Rukh (Delta Cygni). Maximum activity occurs on August 17th so current rates would be one per hour from the northern hemisphere and less than one 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 Local Daylight Time (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.

The large Antihelion (ANT) radiant is currently located at 22:08 (332) -09. This position lies in central Aquarius, two degrees southwest of the fourth magnitude star Theta Aquarii. Due to the large size of this radiant, Antihelion activity may also appear from eastern Capricornus, western Pisces, and southwestern Pegasus as well as Aquarius. 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 two per hour as seen from the northern hemisphere and three per hour as seen from south of the equator. With an entry velocity of 30 km/sec., the averag meteor would be of slow velocity.

The Delta Aquariids (SDA) are still active from a radiant located at 23:28 (352) -13. This position is located in east-central Aquarius, four degrees southeast of the naked eye triple star known as Psi Aquarii. Current hourly rates would be one from the northern hemisphere and two from south of the equator. The radiant 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 Eta Eridanids (ERI) are active from July 24 through August 18 with maximum activity occurring on August 8. The current radiant position is 03:00 (045) -10, which places it in western Eridanus, just one degree southeast of the fourth magnitude star Eta Eridani. Current rates would be near one per hour no matter your location. The radiant is best placed during the last hour before dawn, when it lies highest in a dark sky. With an entry velocity of 66 km/sec., the average Eta Eridanid meteor would be swift.

The Perseids (PER) peak on Sunday morning from a radiant located at 03:12 (048) +58. This position lies near the intersection of Cassiopeia, Perseus, and Camelopardalis. Gamma Persei lies four degrees to the southwest of the radiant. The radiant is circumpolar north of 32 degrees north latitude but best placed during the last hour before the start of morning twilight, when it lies highest in a dark sky. Expected maximum rates, when the radiant is located highest in a dark sky, are near forty per hour as seen from the northern hemisphere and ten per hour as seen from tropical southern latitudes. Rates are slightly reduced due to moonlight, as the 25 percent illuminated moon lies fairly close to the radiant. Activity from this source is not visible south of 35 degrees south latitude. With an entry velocity of 61 km/sec., most activity from this radiant would be swift. For more information on how to watch for Perseid meteors, see the article at: Viewing the 2012 Perseid Meteor Shower.

A 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 less than one per hour, no matter your location. The radiant is currently located at 03:16 (049) +37, which is actually situated in southern Perseus, five degrees southeast of the famous variable star known as Algol (Beta Persei). 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 four per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near six per hour as seen from rural observing sites and two 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 summary of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning August 11/12, but may be used all week.

Kappa Cygnids (KCG) – 19:00 (285) +51   Velocity 23km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – <1 per hour

Antihelions (ANT) – 22:08 (332) -09   Velocity 30km/sec
Northern Hemisphere – 2 per hr   Southern Hemisphere – 3 per hour

Delta Aquariids (SDA) – 23:28 (352) -13   Velocity 42km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 2 per hour

Eta Eridanids (ERI) – 03:00 (045) -10   Velocity 66km/sec
Northern Hemisphere – 1 per hr   Southern Hemisphere – 1 per hour

Perseids (PER) – 03:12 (048) +58   Velocity 61km/sec
Northern Hemisphere – 40 per hr  Southern Hemisphere – 10 per hour

Alpha Triangulids (ATR) – 03:16 (049) +37   Velocity 67km/sec
Northern Hemisphere – <1 per hr Southern Hemisphere – <1 per hour

Clear Skies!
Robert Lunsford
American Meteor Society

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

 

August 18/19 Meteors

Another clear night… The Moon is starting to be a problem in the evening hours. For the rest of the week the Moon will set before the prime meteor watching hours in the early morning.

We are near the peak time of the Kappa Cygnids. This shower produces some of the most notable meteors, often ending with a bright flash. Last night didn’t produce any. Maybe we’ll see more tonight.

Obs  Date(UT)      Time    TOT SPO ANT PER SDA ERI KCG AUD
SAL3 2010-08-19   08h 11m   32  20  4   4   0   2   0   2
ALLS 2010-08-19   07h 35m   10  4   0   5   0   1   0   0

SAL3 - SALSA3 camera in Tucson (Carl Hergenrother)
ALLS - Near all-sky camera in Tucson (Carl Hergenrother)
VIST - Visual observations from Tucson (Carl Hergenrother)
SDG - Camera in San Diego operated by Bob Lunsford
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
PER - Perseids
SDA - Southern Delta Aquariids
ERI - Eta Eridanids
KCG - Kappa Cygnids
AUD - August Draconids

Meteor Activity Outlook for August 14-20, 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 first quarter phase on Monday August 16th. At this time the moon will be located ninety degrees east of the sun and will set near 0100 local daylight time (LDT) for locations in the mid-northern latitudes of the northern hemisphere. This weekend the waxing crescent moon will set just prior to midnight for the locations mentioned above, and will be gone from the sky during the active morning hours. The estimated total hourly rates for evening observers this week is ~3 no matter your location. For morning observers the estimated total hourly rates should be ~35 from the northern hemisphere and ~20 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 14/15. 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 18:14 (273) +62. This position lies in southern Draco, ten degrees north of 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 19:06 (287) +52. 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 Cygnus/Draco border, three degrees southwest of the faint star Kappa Cygni. Maximum activity is now predicted to occur on August 14th. Current rates would be ~2 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.

Antihelions (ANT)

The wide Antihelion (ANT) radiant is now centered at 22:20 (335) -08. This area of the sky lies in central Aquarius, 3 degrees southeast of the 4th magnitude Theta Aquarii. 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 northern Piscis Austrinus, Capricornus, Aquarius, or southern Pegasus could be a candidate for this shower. Rates at this time should be ~2 per hour no matter your location. 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 23:36 (354) -12. This position lies in eastern Aquarius, 3 degrees northwest of the 4th magnitude star Omega2 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 1 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.

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 ~2 per hour at maximum. The radiant is currently located at 03:12 (048) -09. This shower was observed by me during the Perseid maximum last week. The radiant is currently located at 03:12 (048) -09. This area of the sky is located in western Eridanus, 3 degrees east of the faint star Eta Eridani. 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.

Perseids (PER)

The Perseids (PER) reached maximum activity on Friday August 13th with zenith hourly rates (ZHR’s) near 90. They are still active from a radiant located at 03:24 (051) +58. This position actually lies in southern Camelopardalis, eight degrees north of the second magnitude star Mirfak (Alpha 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 ~20 per hour, falling to <10 by the end of the week. Activity from the Perseids is not well seen south south of the equator and completely invisible 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
AUG August Draconids     18h 14m  +61    23    <1    <1
KCG Kappa Cygnids        19h 06m  +52    23     1    <1
ANT Antihelions          22h 20m  -08    30     2     3
SDA Delta Aquariids      23h 36m  -12    42     1     2
ERI Eridanids            03h 12m  -09    64     2     2
PER Perseids             03h 24m  +58    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

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
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