Feb 17-24 Meteors

The non-winter of 2014 (at least for Tucson) continues. And even though most nights see some amount of cirrus, it is clear enough that meteors are detected almost every night. In fact 60 of the past 62 nights have seen at least one meteor detected by my video system.

Most of the recent February activity are Sporadic meteors not affiliated with any known meteor shower.

Obs  Date(UT)      Time    TOT SPO ANT NDL DSE BHE DLE
SAL  2014-02-24   07h 26m   7   6   1   0   -   -   0
SAL  2014-02-23   09h 35m   17  17  0   0   -   -   0
SAL  2014-02-22   08h 17m   18  16  1   0   -   -   1
SAL  2014-02-21   11h 37m   12  10  1   0   1   -   0
SAL  2014-02-20   11h 38m   19  17  1   0   1   -   0
SAL  2014-02-19   10h 21m   13  9   2   1   0   0   1
SAL  2014-02-18   11h 42m   18  14  2   1   1   0   0
SAL  2014-02-17   09h 00m   11  11  0   0   0   0   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
NDL - North Delta Leonids
DSE - Delta Serpentids
BHE - Beta Herculids
DLE - Delta Leonids

Feb 11-16 Meteors

February is usually a slow month for meteor watchers. Even though a surprisingly large number of meteor showers have been discovered in February over the past few years, all are minor and produce few meteors. With no major showers active and even the background rate of sporadic meteors (those showers not affiliated with any shower) near annual lows, February’s meteor rates are low. My observed numbers are even lower on most nights since this month has seen a large number of nights affected by high clouds.

My camera is set up to watch for four minor showers this week.

The North Delta Leonids (NDL) appear to be from a short-period comet with a perihelion of ~0.6 AU and inclination of ~5° resulting in a relatively slow velocity of ~20 km/s. It is possible that near-Earth asteroid 1999 RD32 is the parent of this family. RD32 is a large, dark object ~5 km in diameter and may be cometary in origin.

The Delta Serpentids (DSE) are from a longer period comet with a perihelion of ~1 au and inclination of ~130°. Comet C/1947 F2 (Becvar) is a possible source of these rapid (65 km/s) meteors.

The Beta Herculids (BHE) is a newly discovered shower discovered with data from the network that my camera is a part of. Orbits for the BHEs have not been determined yet though their velocity of ~57 km/s suggest a long-period comet origin. Even less is known about the Delta Leonids (DLE). With a velocity of 20 km/s these meteors are from a short-period comet or even a near-Earth asteroid.

Obs  Date(UT)      Time    TOT SPO ANT NDL DSE BHE DLE
SAL  2014-02-16   09h 53m   11  11  0   0   0   0   0
SAL  2014-02-15   11h 23m   22  18  0   1   1   1   1
SAL  2014-02-14   11h 43m   15  10  3   0   0   2   -
SAL  2014-02-13   11h 11m   11  5   1   1   4   0   -
SAL  2014-02-12   11h 52m   17  12  2   0   2   1   -
SAL  2014-02-11   11h 54m   10  9   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
NDL - North Delta Leonids
DSE - Delta Serpentids
BHE - Beta Herculids
DLE - Delta Leonids

Meteor Activity Outlook for February 15-21, 2014

The Meteor Activity Outlook for the period 2014 February 15-21 has been posted by Bob Lunsford on the American Meteor Society website.

The Outlook has details on meteors from the Antihelion region and the following showers: Alpha Centaurids (ACE), Beta Herculids (BHE) and the Delta Serpentids (DSE).

Meteor Activity for February 8-14, 2014

The Meteor Activity Outlook for the period 2014 January 18-24 has been posted by Bob Lunsford on the American Meteor Society website.

The Outlook has details on meteors from the Antihelion region and the following showers: daytime meteors from comet 45P/Honda-Mrkos-Pajdusakova (unnamed shower), Alpha Centaurids (ACE), and the Beta Herculids (BHE).

Meteor Activity Outlook for February 16-22, 2013

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.

February offers the meteor observer in the northern hemisphere a couple of weak showers plus falling sporadic rates. This may not seem too exiting but you never know when surprises are in store. An errant earth-grazer from the Centaurid complex may shoot northward. Better yet, a bright fireball may light up the sky. February is the start of the fireball season, when an abundance of fireballs seem to occur. This lasts well into April and seems to occur mostly during the early evening hours.

Observers in the southern hemisphere are treated to the Alpha Centaurid peak on the 8th plus the entire Centaurid complex of radiants is active all month long. Sporadic rates also peak this month south of the equator this month adding to the celestial show.

During this period the moon reaches its first quarter phase on Sunday February 17th. At this time the moon is located ninety degrees east of the sun and sets near midnight local standard time (LST) as seen from mid-northern latitudes. As the week progresses the waxing gibbous moon will set during the early morning hours, allowing a few hours of dark skies between the time of moon set and the beginning of morning twilight. The estimated total hourly meteor rates for evening observers this week is near two as seen from the northern hemisphere and four as seen from south of the equator. For morning observers the estimated total hourly rates should be near eight from the mid-northern hemisphere and seventeen 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 February 16/17. 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:

The large Anthelion (ANT) radiant is currently centered at 10:44 (161) +07. This position lies in southern Leo, ten degrees southeast of the first magnitude star Regulus (Alpha Leonis). These meteors may be seen all night long but the radiant is best placed near 0100 LST when it lies on the meridian and is highest in the sky. Rates at this time should 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.

The Alpha Centaurids (ACE) are active from a radiant located at 14:43 (221) -62. This position lies in southeastern Centaurus, very close to the position occupied by the zero magnitude star Rigel Kentaurus (Alpha Centauri). These meteors cannot be seen north of the northern tropical regions. They are best seen from mid-southern latitudes where the radiant lies high in the sky near 0500 local summer time. This shower peaked on February 8th so current rates would be near one per hour as seen from the southern hemisphere. At 56km/sec. the Alpha Centaurids would produce mostly swift meteors.

The Beta Herculids are active through Tuesday from a radiant located at 15:52 (238) +28. This position is actually located in Corona Borealis, four degrees northeast of the second magnitude star Alphecca (Alpha Coronae Borealis). It is suggested that the observer be liberal with shower association as the actual radiant position is not well defined. These meteors are best seen near during the last dark hour before dawn when the radiant lies highest above the horizon in a dark sky. Rates would mostly likely be less than one shower member per hour, no matter your location. Observers in the northern hemisphere have an advantage in that the radiant lies higher in the sky during the morning hours. At 56 km/sec. the Beta Herculids would produce mostly swift meteors.

The IMO video list of radiants has several entries for the Delta Serpentids (DSE). On most nights of possible activity this shower is extremely weak, far less than the weak sporadic rate seen this time of year from the northern hemisphere. On the morning of the February 16th though, it becomes the second most active radiant in the sky. At that time the radiant is located at 16:37 (249) +09, which actually places it in among the stars of Ophiuchus. The nearest bright stars are fourth magnitude Kappa and Iota Ophiuchi, which lie six degrees to the east. This position is well seen from either side of the equator. These meteors are best seen near during the last dark hour before dawn when the radiant lies highest above the horizon in a dark sky. On other mornings rates for this shower are so weak that the chance of sporadic alignment is extremely high. At 57 km/sec. the Delta Serpentids would produce mostly swift meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately six sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near one 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. Rates are reduced during the evening hours 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 .

Anthelions (ANT) – 10:44 (161) +07   Velocity – 30km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – 1 per hr

Alpha Centaurids (ACE) – 14:43 (221) -62   Velocity – 56km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – 1 per hr

Beta Herculids (BHE) – 15:52 (238) +28   Velocity – 56km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Delta Serpentids (DSE) – 16:37 (249) +09   Velocity – 57km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – 1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for February 9-15, 2013

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.

February offers the meteor observer in the northern hemisphere a couple of weak showers plus falling sporadic rates. This may not seem too exiting but you never know when surprises are in store. An errant earth-grazer from the Centaurid complex may shoot northward. Better yet, a bright fireball may light up the sky. February is the start of the fireball season, when an abundance of fireballs seem to occur. This lasts well into April and seems to occur mostly during the early evening hours.

Observers in the southern hemisphere are treated to the Alpha Centaurid peak on the 8th plus the entire Centaurid complex of radiants is active all month long. Sporadic rates also peak this month south of the equator this month adding to the celestial show.

During this period the moon reaches its new phase on Sunday February 10th. At this time the moon is located near the sun and is invisible at night. As the week progresses the waxing crescent moon will enter the evening sky but will not interfere with meteor observing. The estimated total hourly meteor rates for evening observers this week is near three as seen from the northern hemisphere and five as seen from south of the equator. For morning observers the estimated total hourly rates should be near nine from the mid-northern hemisphere and eighteen 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 February 9/10. 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:

The large Anthelion (ANT) radiant is currently centered at 10:16 (154) +09. This position lies in southwestern Leo, three degrees southeast of the first magnitude star Regulus (Alpha Leonis). These meteors may be seen all night long but the radiant is best placed near 0100 LST when it lies on the meridian and is highest in the sky. Rates at this time should be near two per hour as seen from the northern hemisphere and one per hour from south of the equator. With an entry velocity of 30 km/sec., the average Antihelion meteor would be of slow velocity.

The Alpha Centaurids (ACE) are active from a radiant located at 14:10 (212) -60. This position lies in southeastern Centaurus, very close to the position occupied by the first magnitude star Hadar (Beta Centauri). These meteors cannot be seen north of the northern tropical regions. They are best seen from mid-southern latitudes where the radiant lies high in the sky near 0500 local summer time. This shower peaked on February 8th so current rates would be near three per hour as seen from the southern hemisphere. At 56km/sec. the Alpha Centaurids would produce mostly swift meteors.

Activity from the Beta Herculids begins on Wednesday morning February 13th. This also happens to be the morning of maximum activity. This shower was discovered by Juergen Rendtel and Sirko Molau using data from the IMO video database. This shower is active from the 13th through the 19th. On the 13th the radiant is located at 16:27 (247) +24. This position is located in western Hercules, three degrees north of the third magnitude star Kornephoros (Beta Herculis). These meteors are best seen near during the last dark hour before dawn when the radiant lies highest above the horizon in a dark sky. Rates would mostly likely be less than one shower member per hour, no matter your location. At 56 km/sec. the Beta Herculids would produce mostly swift meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately seven 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 four per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.

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

Anthelions (ANT) – 10:16 (154) +09   Velocity – 30km/sec.
Northern Hemisphere – 2 per hr.   Southern Hemisphere – 1 per hr

Alpha Centaurids (ACE) – 14:10 (212) -60   Velocity – 56km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – 3 per hr

Beta Herculids (BHE) – 16:27 (247) +24  Velocity – 56km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Feb 10/11 to 13/14 Meteors

The Moon is approaching Full so nightly rates should drop. This may all be moot as a series of storms are forecast to affect the area starting Wednesday and continuing into next week. Now the question is will we actually get a good soaking or will these storms just bring clouds.

Obs  Date(UT)      Time    TOT SPO ANT BHE
SAL3 2011-02-14   04h 56m   10  10  0   0
ALLS 2011-02-14   11h 32m   9   7   0   2

SAL3 2011-02-13   11h 22m   19  16  3   0
ALLS 2011-02-13   11h 50m   9   8   1   0
HERM 2011-02-13   09h 19m   12  11  1   0

SAL3 2011-02-12   11h 23m   15  13  1   1
ALLS 2011-02-12   11h 38m   5   4   0   1

SAL3 2011-02-11   11h 25m   10  9   0   1   
ALLS 2011-02-11   11h 54m   4   4   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)
VISH - Visual observations from Hermosillo (Salvador Aguirre)
HERM - PARENI camera in Hermosillo (Salvador Aguirre)
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   
BHE - Beta Herculids