Meteor Activity Outlook for January 12-18, 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.

During this period the moon reaches its new phase on Friday January 11th. At this time the moon is located near the sun and will remain invisible at night. Next week the waxing crescent moon will enter the evening sky but will set long before the more active morning hours arrive. The estimated total hourly meteor rates for evening observers this week is near three no matter your location. For morning observers the estimated total hourly rates should be near fifteen from the mid-northern hemisphere and eleven 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 January 12/13. 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 Antihelion (ANT) radiant is currently centered at 08:20 (125) +18. This position lies in central Cancer, four degrees west of the fourth magnitude star Asellus Australis (Delta Cancri). These meteors may be seen all night long but the radiant is best placed near 0100 local standard time (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 December Leonis Minorids (DLM) are currently the most active shower in the sky. The radiant is located at 12:16 (184) +19. This position lies in southwestern Coma Berenices, seven degrees northeast of the second magnitude star Denebola (Beta Leonis). These meteors are best seen near 0400 LST when the radiant lies highest above the horizon. This shower peaked on December 17th so current rates would be near two per hour as seen from the northern hemisphere and one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

IMO Shower #14 is an unnamed shower active in mid-January. Peak activity occurs on January 18th from a radiant located at 13:16 (199) -20. This position is located in southwestern Virgo, nine degrees south of the first magnitude star Spica (Alpha Virginis). This radiant does not rise until after midnight so activity is strictly limited to the morning hours. Rates would mostly likely be less than one shower member per hour, no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 70 km/sec. IMO Shower #14 would produce mostly swift meteors.

The Canum Venaticids (CVN) are a new shower discovered by Peter Brown and his associates at the University of Western Ontario, using meteor orbits obtained by radar. This activity was verified by the IMO video network which has 271 possible candidates in its database. This shower is best seen from January 11-17, with maximum activity occurring on the 11th. Rates never exceed one shower member per hour yet it is the 3rd strongest radiant in the sky on the mornings of January 13 and 14. The radiant is located near 14:08 (212) +36, which places it in southeastern Canes Venatici. This position also lies 5 degrees southwest of the famous third magnitude double star known as Cor Caroli (Alpha Canum Venaticorum). Do not be too strict with this position as the radiant is not well defined at this point. Any meteors from this area this time of year should be suspected as possible Canum Venaticids. I would suggest using radiant distance and velocity to further determine possible shower association. These meteors encounter the atmosphere at 59 km/sec., which would produce mostly swift meteors. These meteors are best seen during the last few hours before dawn, when the radiant lies highest in a dark sky. This activity would be difficult to view from the southern hemisphere as the radiant lies low in the north at dawn.

The Theta Coronae Borealids (TCB) are another new shower discovered by Peter Brown and his associates at the University of Western Ontario, using meteor orbits obtained by radar. This activity was also verified by the IMO video network which has 189 possible candidates in its database. This shower is only active on six nights centered on January 16th. Rates again never exceed one shower member per hour yet it is the 3rd strongest radiant in the sky on January 16th. On that morning the radiant is located at 15:40 (235) +51, which places it twenty degrees north of Theta Coronae Borealis. Earlier visual observations must have placed the radiant much too far south. Either that or this shower is completely different from the early TCB radiant. The closest bright star to the radiant is third magnitude Edasich (Iota Draconis), which lies eight degrees to the north. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 39 km/sec. the Theta Coronae Borealids would produce meteors of medium velocity.

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 two 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 two 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 .

Antihelions (ANT) – 08:20 (125) +18   Velocity – 30km/sec.
Northern Hemisphere – 2 per hr.   Southern Hemisphere – 1 per hr

December Leonis Minorids (DLM) – 12:16 (184) +19   Velocity – 64km/sec.
Northern Hemisphere – 2 per hr.   Southern Hemisphere – 1 per hr

IMO #14 – 13:16 (199) -20   Velocity – 70km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Caneum Venaticids(CVN) – 14:08 (212) +36   Velocity – 59km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Theta Coronae Borealids (TCB)  – 15:40 (235) +51   Velocity – 39km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for December 29-January 4, 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.

During this period the moon wanes from its current full phase to a little more than one-half illuminated on January 4, 2013.  This weekend the waning gibbous moon will rise during the early evening hours and will effectively ruin the sky with intense moonlight the remainder of the night. As the week progresses the moon will rise a little later each evening but the more active morning hours will still be compromised by moonlight. The strong Quadrantid meteor shower will peak on Thursday morning January 3rd, with a bright gibbous moon located near the Leo-Virgo border. Activity can be still seen from the Quadrantids if your skies are clear and transparent. It would also be wise to keep the moon out of your field of view by facing the north to east quadrant of the sky. The estimated total hourly meteor rates for evening observers this week is near two for observers located at mid-northern latitudes and one for observers in mid-southern latitudes. For morning observers the estimated total hourly rates should be near five from the mid-northern hemisphere and three 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. Rates are reduced during this entire period due to intense 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 December 29/30. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The table below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning . Details of each shower will again be provided next week when the situation with moonlight improves.

Antihelions (ANT) – 07:24 (111) +21   Velocity – 30km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – <1 per hr

Alpha Hydrids (AHY) – 08:12 (123) -07   Velocity – 45km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

January Leonids (JLE) – 09:48 (147) +25   Velocity – 45km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

December Leonis Minorids (DLM) – 11:20 (170) +26   Velocity – 64km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Coma Berenicids (COM) – 12:20 (185) +13   Velocity – 69km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Dec. Sigma Virginids (DSV) – 14:16 (214) +02    Velocity – 44km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Quadrantids (QUA) – 15:24 (231) +49   Velocity – 42km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for December 22-28, 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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. This activity will be tempered by a bright moon during the first week of the month. The next two weeks are moon-free and offer the meteor observer ample opportunities to view some celestial fireworks. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 13. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon reaches its full  phase on Friday December 28th. At this time the moon is located opposite the sun and will remain in the sky all night long. This weekend the waxing gibbous moon will set during the early morning hours and will allow several hours of dark sky viewing before dawn arrives. As the week progresses this window of dark skies shrinks until late in the week when the moon will remain above the horizon all night long. The estimated total hourly meteor rates for evening observers this week is near three for observers located at mid-northern latitudes and two for observers in mid-southern latitudes. For morning observers the estimated total hourly rates should be near twenty four from the mid-northern hemisphere and ten 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. Rates are reduced during the evening hours 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 December 22/23. 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:

Now that the activity from particles produced by comet 2P/Encke has ceased encountering the Earth, the Taurid showers for 2012 are over and we resume reporting activity from the Antihelion (ANT) radiant. This is not a true radiant but rather activity caused by the Earth’s motion through space. As the Earth revolves around the sun it encounters particles orbiting in a pro-grade motion that are approaching their perihelion point. They all appear to be radiating from an area near the opposition point of the sun, hence the name Antihelion. These were once recorded as separate showers throughout the year but it is now suggested to bin them into their category separate from true showers and sporadics. This radiant is a very large oval some thirty degrees wide by fifteen degrees high. Activity from this radiant can appear from more than one constellation. The position listed here is for the center of the radiant which is currently located at 06:56 (104) +22. This position lies in central Gemini, four degrees southeast of the third magnitude star Mebsuta (Epsilon Geminorum). Antihelion activity may also appear from eastern Taurus, northeastern Orion, Cancer, Canis Minor, Monoceros, or southern Auriga. This radiant is best placed near midnight local standard time (LST) when it lies on the meridian and is highest in the sky. Rates at this time should be near three per hour as seen from the northern hemisphere and two 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 December Leonis Minorids (DLM) are active from a radiant located at 10:52 (163) +30. This position lies in central Leo Minor, approximately four degrees southwest of the third magnitude star Alula Borealis (Nu Ursae Majoris). These meteors are best seen near 0400 LST when the radiant lies highest above the horizon. This shower peaked on December 17th so current rates would be near two per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

The Coma Berenicids (COM) are best seen from December 23 through January 2. Maximum activity occurs on January 1st when this shower is the fourth strongest in the sky. The current radiant position lies at 11:46 (176) +18. This position actually lies eastern Leo, four degrees northwest of the second magnitude star Denebola (Beta Leonis). Current hourly rates would most likely be less than one shower member per hour no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 69 km/sec. The Coma Berenicids would produce mostly swift meteors.

IMO Shower #247 seems to be a northern counterpart of the Coma Berenicids. It shares the same right ascension (celestial longitude) as the Coma Berenicids but is located nearly twenty degrees further north. The activity period is shorter than the Coma Berenicids as it is best seen from December 24-27, with maximum activity occurring on the 24th. Maximum rates would be near one per hour as seen from the northern hemisphere and less than one as seen from south of the equator. At maximum activity the radiant is located at 12:00 (180) +37, which is located in a remote area of southeastern Ursa Major. The nearest bright star would be third magnitude star Alula Borealis (Nu Ursae Majoris), which is located ten degrees to the southwest. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 66 km/sec. IMO Shower #247  would produce mostly swift meteors.

Studies by Sirko Molau and Juergen Rendtel of the IMO discovered an active radiant in Virgo this time of year. The December Sigma Virginids (DSV) are active through most of December and the first week of January. Visual observers have their best chance at catching these meteors from December 17 through January 1st. Maximum activity occurs on December 31st. Current rates would most likely be less than one shower member no matter you location. The current radiant location is at 13:52 (208) +04 which place it in northern Virgo some four degrees northwest of the fourth magnitude star Tau Virginis. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 69 km/sec. the December Sigma Virginids would produce mostly swift meteors.

The Ursids (URS) peak on the morning of December 22 from a radiant located at 14:32 (218) +75. This position lies in eastern Ursa Minor, just northeast of the second magnitude star Kochab (Beta Ursa Minoris). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. Due to the extreme northerly location meteors from this shower are not visible from the southern hemisphere. On the morning of maximum, hourly rates of between 5-10 Ursids may be seen during the late morning hours. At 33 km/sec. the Ursids produce mostly medium-slow meteors.

The Quadrantids (QUA) begin to appear in weak numbers on the morning of December 26th. The radiant is then located near 15:04 (226) +53, which places it in northern Bootes, eight degrees southwest of the third magnitude star Edasich (Iota Draconis). Rates at this time would be less than one shower member per hour no matter your location. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 42 km/sec. the Quadrantids would produce mostly meteors of medium velocity.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately eleven 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 list below presents a condensed version of the expected activity this week.
Rates and positions are exact for Saturday night/Sunday morning.

Antihelions (ANT) – 06:56 (104) +22   Velocity – 30km/sec.
Northern Hemisphere – 3 per hr.   Southern Hemisphere – 2 per hr

December Leonis Minorids (DLM) – 10:52 (163) +30   Velocity – 64km/sec.
Northern Hemisphere – 2 per hr.   Southern Hemisphere – <1 per hr

Coma Berenicids (COM) – 11:46 (176) +18   Velocity – 69km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

IMO #247  – 12:00 (180) +37   Velocity – 66km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – <1 per hr

Dec. Sigma Virginids (DSV) – 13:52 (208) +04  Velocity – 44km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Ursids (URS) – 13:58 (210) +76   Velocity – 33km/sec.
Northern Hemisphere – 7 per hr. Southern Hemisphere – 0 per hr

Quadrantids (QUA) – 15:04 (226) +53    Velocity – 42km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for December 15-21, 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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. This activity will be tempered by a bright moon during the first week of the month. The next two weeks are moon-free and offer the meteor observer ample opportunities to view some celestial fireworks. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 13. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon reaches its first quarter phase on Wednesday December 19th. At this time the moon is located ninety degrees east of the sun and will set near midnight local standard time (LST). This weekend the waxing crescent moon will set during the early evening hours and will not cause any problems to meteor observers. As the week progresses the moon will set later and later, but will still allow unhampered views of the more active morning sky. 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 thirty from the mid-northern hemisphere and sixteen 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. Rates are slightly reduced during the evening hours 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 December 15/16. 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:

Now that the activity from particles produced by comet 2P/Encke has ceased encountering the Earth, the Taurid showers for 2012 are over and we resume reporting activity from the Antihelion (ANT) radiant. This is not a true radiant but rather activity caused by the Earth’s motion through space. As the Earth revolves around the sun it encounters particles orbiting in a prograde motion that are approaching their perihelion point. They all appear to be radiating from an area near the opposition point of the sun, hence the name Antihelion. These were once recorded as separate showers throughout the year but it is now suggested to bin them into their category separate from true showers and sporadics. This radiant is a very large oval some thirty degrees wide by fifteen degrees high. Activity from this radiant can appear from more than one constellation. The position listed here is for the center of the radiant which is currently located at 06:28 (097) +23. This position lies in western Gemini near the third magnitude star Mebsuta (Epsilon Geminorum). Antihelion activity may also appear from eastern Taurus, northeastern Orion, or southern Auriga. This radiant is best placed near midnight LST when it lies on the meridian and is highest in the sky. Rates at this time should be near three per hour as seen from the northern hemisphere and two 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 December Monocerotids (MON) are active from December 7th through the 18th. Peak activity occurred on December 8th so current rates should be less than one per hour no matter your location. The radiant is located at 07:00 (105) +07. This position lies in eastern Monoceros, ten degrees east of the zero magnitude star Procyon (Alpha Canis Minoris).  The Monocerotids are best seen near 0100 LST when the radiant lies highest above the horizon. At 41 km/sec. the Monocerotids produce mostly meteors of medium velocity.

The Geminids (GEM) reached maximum activity on Thursday evening/Friday morning December 13/14. This weekend will be your last good opportunity to see any Geminids in 2012 as activity ceases next week. The radiant is currently located at 07:40 (115) +32, which places it in northeastern Gemini, just east of the second magnitude star Castor (Alpha Geminorum). Rates this weekend, when the radiant lies high in the sky, would be 20-40 per hour (depending on your viewing conditions) on the night of 14/15 and 10-20 per hour on the night of 15/16. Geminid meteors strike the atmosphere at 35km/sec, which will produce meteors of medium-slow velocity.

The Sigma Hydrids (HYD) are active from November 26 through December 20. Maximum activity occurred on December 6, so current rates would be near one per hour no matter your location. The radiant is located at 08:47 (132) +01. This position lies in western Hydra, just south of the group of fourth magnitude stars that make up the “head” of the water serpent. These meteors are best seen near 0300 LST when the radiant lies highest above the horizon. At 61 km/sec. the Sigma Hydrids produce mostly swift meteors.

The December Leonis Minorids (DLM) are active from a radiant located at 10:32 (158) +32. This position lies in central Leo Minor, approximately ten degrees northeast of the third magnitude star Zeta Leonis. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. This shower peaks on December 17th so current rates would be near two per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

On the nights of December 19-21, weak activity from the Rho Leonids  (RLE) may be noticed. Sirko Molau and Juergen Rendtel of the IMO have found the actual activity range is December 17-23, but away from the nights mentioned above, the display is very weak. Previous radiants for this shower were further north. Video results give a position at maximum near 10:34 (159) -05. This actually places it in central Sextans, some fifteen degrees southeast of the first magnitude star Regulus (Alpha Leonis). Rates could approach one shower member per hour during the last few hours before dawn on the nights previously mentioned. At 69 km/sec. the Rho Leonids would produce mostly swift meteors.

On the nights of December 15/16 and 16/17, weak activity from the Virgo/Corvus border may be noticed. This currently unnamed source is active from December 5-27, but incredibly weak except for the two nights mentioned above. The exact radiant position for IMO Shower #239 is 12:52 (193) -11. This places it some ten degrees west of the first magnitude star Spica (Alpha Virginis). At 70 km/sec. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. IMO Shower #239 would produce mostly swift meteors.

Another shower found by Sirko Molau and Juergen Rendtel of the IMO are the December Sigma Virginids (DSV). This radiant is active through most of December and the first week of January. Visual observers have their best chance at catching these meteors from December 17 through January 1st. Maximum activity occurs on December 31st. The current radiant location is 13:32 (203) +05, which places it in northern Virgo some five degrees north of the third magnitude star Heze (Zeta Virginis). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. At 69 km/sec. the December Sigma Virginids would produce mostly swift meteors.

Activity from the Ursids (URS) should begin to appear during the mid-week period from a radiant located at 13:58 (210) +76. This position lies in eastern Ursa Minor, fifteen degrees east of the second magnitude star Kochab (Beta Ursa Minoris). It must be remembered that the length of degrees are smaller in high declinations so the radiant is actually closer to this star than these figures imply. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Maximum activity is not expected until Saturday December 22th, so current hourly rates this week would probably be less than one. On the morning of maximum, hourly rates of between 5-10 Ursids may be seen. At 33 km/sec. the Ursids produce mostly medium-slow meteors.

Lastly, the December Alpha Draconids (DAD) are active from December 4-16. Maximum activity occurred on December 5. The radiant is currently located at 14:08 (212) +57. This position actually lies in northeastern Ursa Major, ten degrees northeast of the second magnitude double star Mizar (Zeta Ursae Majoris). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Expected hourly rates would be less than one no matter your location. At 44 km/sec. the Alpha Draconids produce mostly medium speed meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately eleven 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 seven 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 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.

Antihelions (ANT) – 06:28 (097) +23   Velocity – 30km/sec.
Northern Hemisphere – 3 per hr.   Southern Hemisphere – 2 per hr

Dec. Monocerotids (MON) – 07:00 (105) +07   Velocity – 41km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr

Geminids (GEM) -07:40 (115) +32   Velocity – 35km/sec.
Northern Hemisphere – 10 per hr.   Southern Hemisphere – 5 per hr

Sigma Hydrids (HYD) -08:47 (132) +01   Velocity – 61km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – 1 per hr

December Leonis Minorids (DLM) – 10:32 (158) +32   Velocity – 64km/sec.
Northern Hemisphere – 2 per hr.  Southern Hemisphere – <1 per hr

Rho Leonids (RLE) – 10:34 (159) -05   Velocity – 69km/sec.
Northern Hemisphere – 1 per hr.  Southern Hemisphere – 1 per hr

IMO #239  – 12:52  (193) -11   Velocity – 69km/sec.
Northern Hemisphere – 2 per hr. Southern Hemisphere – <1 per hr

Dec. Sigma Virginids (DSV) – 13:32 (203) +05   Velocity – 44km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Ursids (URS)  – 13:58 (210) +76    Velocity – 33km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

December Alpha Draconids (DAD) – 14:08 (212) +57   Velocity – 44km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for December 8-14, 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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. This activity will be tempered by a bright moon during the first week of the month. The next two weeks are moon-free and offer the meteor observer ample opportunities to view some celestial fireworks. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 13. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon reaches its new phase on Thursday December 13th. At this time the moon is located near the sun and will be invisible at night. This weekend the waning crescent moon will rise during the early morning hours. It will be a minor inconvenience that can be overcome by simply viewing with the moon at your back.  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 sixteen 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. Rates are slightly reduced during the morning hours 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 December 8/9. 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:

Meteors from comet 46P\Wirtanen? There is the possibility that we may be able to see meteor activity from comet 46P\Wirtanen as the Earth passes through several filaments of material produced when the comet passed through perihelion during the first half of the 20th century. This is strictly an evening display as any meteors from this source would have a radiant of 23:48 (357) +04. This position lies in western Pisces, just east of the circle of faint stars known as the “Circlet”. This area of the sky is best seen as it becomes dark as it culminates between 1800 and 1900 (6pm and 7pm) local standard time. The first of these encounters is with the material shed in 1947. The expected peak is at 06:21 Universal Time (UT) on December 11th. This corresponds to 22:21 (10:21pm) PST and 23:21 (11:21pm) MST on Monday evening December 10th. The radiant is too low for any activity to be seen in the eastern half of North America. The second encounter is material from 1941. This peak is expected to occur at 10:20 UT on December 12th. This is too late for North America but observers in Hawaii may be able to see some of this activity. The third encounter is produced from the 1934 return. This peak is expected to occur at 12:30 UT on December 13th. This timing favors the western Pacific area. The last possible encounter is produced by the 1927 return. This peak is expected to occur at 00:02 UT on December 14th. This corresponds to 19:02 (7:02pm) EST and 18:02 (6:02pm) CST on the evening of December 13th. This timing favors the eastern half of North America. If any meteors are produced from this source, they would be extremely slow.

The last of the Northern Taurids (NTA) can be seen this weekend from a radiant centered at 05:26 (082) +27. This area of the sky lies in northeastern Taurus, two degrees south of the second magnitude star El Nath (Beta Tauri). The radiant is best placed near 0100 LST, when it lies highest above the horizon. Maximum activity occurred on November 13th so current hourly rates would be near one from the northern hemisphere and less than one from south of the equator. Meteors from the Northern Taurids strike the atmosphere at 29km/sec., which would produce meteors of slow velocity.

The Monocerotids (MON) are active from December 7th through the 18th. Peak activity occurs on December 8th with the radiant is located at 06:36 (099) +08. This position lies in northern Monoceros, eight degrees east of the first magnitude orange star Betelgeuse (Alpha Orionis). Current rates should be near one per hour no matter your location. The Monocerotids are best seen near 0100 LST when the radiant lies highest above the horizon. At 41 km/sec. the Monocerotids produce mostly meteors of medium velocity.

The Geminids (GEM) reach maximum activity on Thursday evening/Friday morning December 13/14, when approximately 75 shower members can be seen each hour from rural observing sites. While the Geminids are currently the most active radiant in the sky, rates this weekend will only be near five shower members per hour. Rates will increase dramatically as we approach the maximum date and the moon wanes. The radiant is currently located at 07:14 (109) +33. This position lies in northern Gemini, four degrees west of the second magnitude star Castor (Alpha Geminorum).  Although Geminid meteors can be seen all night long, they are best seen near 0200 LST when the radiant lies highest above the horizon. Geminid activity can be seen from the southern hemisphere but at much reduced rate. As seen from south of the equator, Geminid activity could only be seen for a few hours before and after 0200 LST. At 35 km/sec. the Geminids produce mostly meteors of medium velocity. This is one of the few displays that can be well seen prior to midnight. Geminid meteors seen just after dusk will be very long with a long duration. This is due to the fact that the radiant will lie near the horizon and any Geminid meteor seen be just be skimming the upper regions of the atmosphere. Therefore they will take longer to disintegrate in the much less dense portion of the atmosphere. Geminid meteors strike the atmosphere at 35km/sec, which will produce meteors of medium-slow velocity.

The Puppid-Velids (PUP) are a vast complex of weak radiants located in the constellations of Puppis and Vela. Visual plots and photographic studies have revealed many radiants in this area during November and December. The combined strength of these radiants can produce a zenith hourly rate (ZHR) of ten at maximum, which occurs near December 7. Actual hourly rates will be much less unless you happen to be observing from the deep Southern Hemisphere. The center of this activity is currently located at 08:08 (124) -45. This position lies in western Vela, three degrees northeast of the second magnitude star Gamma Velorum. These meteors are best seen near 0300 LST when the radiant lies highest above the horizon in a dark sky. Observers located in the Southern Hemisphere have an advantage viewing this shower as the radiant will rise higher into their sky allowing more activity to be seen. At 40 km/sec. the Puppid-Velids produce meteors of average velocity.

The Sigma Hydrids (HYD) are active from November 26 through December 20. Maximum activity occurred on December 6 and this radiant is currently the third most active in the sky. The radiant is located at 08:24 (126) +02. This position lies in western Hydra, just west of the group of fourth magnitude stars that make up the “head” of the water serpent. These meteors are best seen near 0300 LST when the radiant lies highest above the horizon. Current rates would be near three per hour no matter your location. At 61 km/sec. the Sigma Hydrids produce mostly swift meteors.

The December Leonis Minorids (DLM) are active from a radiant located at 10:08 (152) +36. This position lies in central Leo Minor, approximately twelve degrees north of the third magnitude star Zeta Leonis. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. This shower peaks on December 17th so current rates would be near one per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

Lastly, the December Alpha Draconids (DAD) are active from December 4-16. Maximum activity occurred on December 5. The radiant is currently located at 13:40 (205) +60. This position actually lies in northeastern Ursa Major, direct between the fourth magnitude star Thuban (Alpha Draconis) and the second magnitude double star Mizar (Zeta Ursae Majoris). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Expected hourly rates would be less than one no matter your location. At 44 km/sec. the Alpha Draconids produce mostly medium speed 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 three per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near four 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 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.

Northern Taurids (NTA) -  05:26 (082) +27   Velocity – 29km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – <1 per hr

Dec. Monocerotids (MON) – 06:36 (099) +08   Velocity – 41km/sec.
Northern Hemisphere – 1 per hr. Southern Hemisphere – 1 per hr

Geminids (GEM) – 07:14 (109) +33   Velocity – 35km/sec.
Northern Hemisphere – 5 per hr.   Southern Hemisphere – 3 per hr

Puppid-Velids (PUP) – 08:08 (124) -45   Velocity – 40km/sec.
Northern Hemisphere – 1 per hr. Southern Hemisphere – 5 per hr

Sigma Hydrids (HYD) – 08:24 (126) +02   Velocity – 61km/sec.
Northern Hemisphere – 3 per hr.   Southern Hemisphere – 3 per hr

December Leonis Minorids (DLM) – 10:08 (152) +36   Velocity – 64km/sec.
Northern Hemisphere – 1 per hr. Southern Hemisphere – <1 per hr

December Alpha Draconids (DAD) – 13:40 (205) +60   Velocity – 44km/sec.
Northern Hemisphere – 1 per hr. Southern Hemisphere – <1 per hr

Clear Skies!
Robert Lunsford
American Meteor Society

Meteor Activity Outlook for January 7-13, 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.

During this period the moon reaches it full phase on Monday January 9th. At this time the moon will be located opposite the sun and will be above the horizon the entire night. This is the worst time to try and view meteor activity as the glare from the bright moon will obscure all but the brightest meteors. As the week progresses a small window of dark skies is available between the end of evening twilight and moonrise. Unfortunately this is the worst time of night to try and view meteor activity as rates will only be a couple of meteors per hour. Conditions improve next week as the moon passes its last quarter phase. The estimated total hourly rates for evening observers this week is near one no
matter your location. For morning observers the estimated total hourly rates should be near five as seen from mid-northern latitudes and three from mid-southern latitudes. 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. Rates this week 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 January 7/8. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

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
ANT Antihelions           08h 00m  +19    30     1    <1
AHY Alpha Hydrids         08h 40m  -09    45    <1    <1
DLM Dec Leonis Minorids   11h 52m  +22    64    <1    <1
QUA Quadrantids           15h 28m  +49    42    <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

Meteor Activity Outlook for December 31, 2011 to January 6, 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.

January is best known for the Quadrantids, which have the potential of being the best shower of the year. Unfortunately this shower is short lived and occurs during some of the worst weather in the northern hemisphere. Due to the high northern declination (celestial latitude) and short summer nights, little of this activity can be seen south of the equator. Sporadic rates are generally similar in both hemispheres this month. Sporadic rates are falling though for observers in the northern hemisphere and rising as seen from the southern hemisphere.

During this period the moon reaches it first quarter phase on Sunday January 1st. At this time the moon will be located ninety degrees east of the sun and will set near midnight local standard time (LST). As the week progresses the waxing gibbous moon will set later in the morning hours, shrinking the window of opportunity to view under a dark sky. The estimated total hourly rates for evening observers this week is near three as seen from the northern hemisphere and two as seen from the southern hemisphere. For morning observers the estimated total hourly rates should be near fifteen as seen from mid-northern latitudes and ten from mid-southern latitudes. 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 December 31st/January 1st. 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 Antihelion (ANT) radiant is currently located at 07:32 (113) +21. This position lies in eastern Gemini, two degrees east of the fourth magnitude star Wasat (Delta Geminorum). Due to the large size of this radiant, Antihelion activity may also appear from Monoceros, Canis Minor, or Cancer. This radiant is best placed near 0100 LST, when it lies on the meridian and is located highest in the sky. Rates at this time should be near 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 Hydrids (AHY) are active from December 31st through January 9th. Peak activity occurs on January 1st from a radiant located at 08:24 (126) -08. This position lies in extreme western Hydra, fifteen degrees west of the second magnitude star Alphard (Alpha Hydrae). Rates would most likely be near one per hour, no matter your location. The Alpha Hydrids are best seen near 0200 LST when the radiant lies highest above the horizon. At 45 km/sec. the Alpha Hydrids produce mostly meteors of medium velocity.

Studies of the IMO’s video database by Sirko Molau and Juergen Rendtel has shown another active radiant in Leo this time of year. The January Leonids (JLE) are active from January 1st to 6th with maximum activity occurring on January 2nd. On the 2nd the radiant is located at 09:46 (147) +24. This position lies in western Leo just west of the third magnitude star Algenubi (Epsilon Leonis). This is a very minor display with hourly rates of less than one expected, even at maximum activity. They are best seen near 0300 LST when the radiant lies highest above the horizon. At 54 km/sec. the January Leonids (JLE) produce mostly meteors of medium-swift velocity.

The December Leonis Minorids (DLM) are active from a radiant located at 11:27 (172) +25. This position lies in a blank area of northeastern Leo. The nearest bright star is third magnitude Zosma (Delta Leonis), which lies six degrees to the southwest. These meteors are best seen near 0500 local standard time (LST) when the radiant lies highest above the horizon. This shower peaked on December 20th so current rates would be near one per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

The Quadrantids (QUA) or January Bootids are active from January 1st through the 10th. A sharp maximum is predicted to occur near 0730 Universal Time on the 4th. This corresponds to 02:30 EST and 23:30 PST (January 3rd). This is good timing for viewers located in eastern North America as the radiant will rising above the northeastern horizon. It would even be better if the maximum were a it later as the radiant would be located higher in the sky, producing more activity. Rates will depend on the exact time of maximum and whether the moon is still above the horizon. Assuming the 0730 UT timing is correct, the further one is located in North America, the better. Eastern observers may be able to see 60-75 Quadrantids per hour. If your skies are very clear and dark, allowing you to see faint meteors, your rates could top 100 per hour. Observers located in the western portions of North American will have lower rates but will also have the opportunity to see Quadrantid “earthgrazers”. Earthgrazers are meteors that skim the upper portion of the atmosphere therefore lasting much longer than normal and producing long trails in the sky. These meteors can only be seen when the radiant lies close to the horizon. As the radiant rises, the meteor paths will become shorter with shorter durations. Observers in the northern hemisphere outside of North America can expect to see a maximum of 25 Quadrantids per hour between moon set and dawn. Observers south of the equator will see little of this display as the radiant will have little chance to clear the horizon before morning twilight interferes.

At maximum the radiant is located at 15:21 (230) +49. This position lies in a barren  region of extreme northern Bootes, ten degrees northeast of the fourth magnitude star Beta Bootis. At 42 km/sec. the Quadrantids produce meteors of medium velocity. During exceptional activity some Quadrantid fireballs may be witnessed.

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 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 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
ANT Antihelions           07h 32m  +21    30     2     1
AHY Alpha Hydrids         08h 24m  -08    45     1     1
JLE January Leonids       11h 04m  +28    54    <1    <1
DLM Dec Leonis Minorids   11h 27m  +25    64     1    <1
QUA Quadrantids           15h 21m  +49    42    <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

Meteor Activity Outlook for December 24-30, 2011

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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. Unfortunately in 2011, the moon will spoil much of this activity as I reaches its full phase on the 10th. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 14. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon reaches it new phase on Saturday December 24th. At this time the moon will be located near the sun and will be invisible at night. As the week progresses the waxing crescent moon will enter the evening sky but will not interfere with meteor observing as it is thin and will set long before the active morning hours arrive. The estimated total hourly rates for evening observers this week is near four as seen from the northern hemisphere and three as seen from the southern hemisphere. For morning observers the estimated total hourly rates should be near fifteen as seen from mid-northern latitudes and eight from mid-southern latitudes. 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 December 24/25. 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:

Now that particles produced by comet 2P/Encke are no longer encountering the Earth, the Taurid showers for 2011 are over and we resume reporting activity from the Antihelion (ANT) radiant. This is not a true radiant but rather activity caused by the Earth’s motion through space. As the Earth revolves around the sun it encounters particles orbiting in a prograde motion that are approaching their perihelion point. They all appear to be radiating from an area near the opposition point of the sun, hence the name Antihelion. These were once recorded as separate showers throughout the year but it is now suggested to bin them into a category separate from true showers and sporadics. This radiant is a very large oval some thirty degrees wide by fifteen degrees high. Activity from this radiant can appear from more than one constellation. The position listed here is for the center of the radiant which is currently located at 07:04 (106) +22. This position lies in central Gemini, four degrees west of the fourth magnitude star Wasat (Delta Geminorum). Antihelion activity may also appear from Monoceros, northeastern Orion, Canis Minor, or Cancer. This radiant is best placed near midnight local standard time (LST), when it lies on the meridian and is located 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 December Leonis Minorids (DLM) are active from a radiant located at 11:04 (166) +28. This position lies in eastern Leo Minor, six degrees northwest of the third magnitude star Zosma (Delta Leonis). These meteors are best seen near 0500 local standard time (LST) when the radiant lies highest above the horizon. This shower peaked on December 20th so current rates would be near two per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

The last of the Ursids (URS) may be seen this weekend from a radiant located at 14:40 (220) +75. This position lies in eastern Ursa Minor, two degrees north of the second magnitude star Kochab (Beta Ursa Minoris). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Maximum activity is on Friday December 23th, so hourly rates this weekend would probably be less than one. On the morning of maximum, hourly rates of between 5-10 Ursids may be seen. At 33 km/sec. the Ursids produce mostly medium-slow meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately eleven 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 seven 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 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
ANT Antihelions           07h 04m  +22    30     2     1
DLM Dec Leonis Minorids   11h 04m  +28    64     2     1
URS Ursids                14h 40m  +75    33    <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

Meteor Activity Outlook for December 17-23, 2011

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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. Unfortunately in 2011, the moon will spoil much of this activity as I reaches its full phase on the 10th. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 14. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon reaches it last quarter phase on Sunday December 18th. The half illuminated moon is still very bright and must be kept out of your field of view for successful meteor observations. During this period, the evening hours, which are unfortunately much less active with meteors, will be completely free of any interfering moonlight.  As the week progresses the moon will wane in phase and will rise approximately forty-five minutes later with each passing night. With this scenario, viewing conditions during the more active morning hours will improve with each passing night. The estimated total hourly rates for evening observers this week is near five as seen from the northern hemisphere and three as seen from the southern hemisphere. For morning observers the estimated total hourly rates should be near twelve two as seen from mid-northern latitudes and eight from mid-southern latitudes. 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 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 December 17/18. 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 weekNow that particles produced by comet 2P/Encke are no longer encountering the Earth, the Taurid showers for 2011 are over and we resume reporting activity from the Antihelion (ANT) radiant. This is not a true radiant but rather activity caused by the Earth’s motion through space. As the Earth revolves around the sun it encounters particles orbiting in a prograde motion that are approaching their perihelion point. They all appear to be radiating from an area near the opposition point of the sun, hence the name Antihelion. These were once recorded as separate showers throughout the year but it is now suggested to bin them into a category separate from true showers and sporadics. This radiant is a very large oval some thirty degrees wide by fifteen degrees high. Activity from this radiant can appear from more than one constellation. The position listed here is for the center of the radiant which is currently located at 06:36 (099) +23. This position lies in western Gemini, three degrees southwest of the third magnitude star Epsilon Geminorum. Antihelion activity may also appear from eastern Taurus, northeastern Orion, or southern Auriga. This radiant is best placed near midnight local standard time (LST), when it lies on the meridian and is located 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 last of the Monocerotids (MON) may be seen this weekend from a radiant located at 07:03 (106) +07. This position lies on the Monoceros/Canis Minor border, ten degrees west of the brilliant zero magnitude star Procyon (Alpha Canis Minoris). Rates would be less than one per hour no matter your location. The Monocerotids are best seen near 0100 LST when the radiant lies highest above the horizon. At 41 km/sec. the Monocerotids produce mostly meteors of medium velocity.

The last of the Sigma Hydrids (HYD) may be seen this weekend from a radiant located at 08:54 (134) +00. This position lies in western Hydra, five degrees south of the third magnitude star Zeta Hydrae. Rates would be less than one per hour no matter your location. The Sigma Hydrids are best seen near 0300 LST when the radiant lies highest above the horizon. At 61 km/sec. the Sigma Hydrids produce mostly swift meteors.

The December Leonis Minorids (DLM) are active from a radiant located at 10:39 (160) +31. This position lies in eastern Leo Minor, ten degrees northeast of the third magnitude star Zeta Leonis. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. This shower peaks on December 20th so current rates would be near one per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

The Coma Berenicids (COM) are active from a radiant located at 11:51 (178) +18. This position actually lies in eastern Leo, two degrees north of the second magnitude star Denebola (Beta Leonis). These meteors are best seen near 0600 LST when the radiant lies highest above the horizon. This shower peaked on December 16th so current rates would be near one per hour no matter your location. This week will be your only opportunity to see these meteors as the shower will be over by the 23rd. At 65 km/sec. the Coma Berenicids produce mostly swift meteors.

Activity from the  Ursids (URS) may begin to appear this weekend from a radiant located at 13:58 (210) +76. This position lies in eastern Ursa Minor, fifteen degrees east of the second magnitude star Kochab (Beta Ursa Minoris). It must be remembered that the length of degrees are smaller in high declinations so the radiant is actually closer to this star than these figures inply. These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Maximum activity is not expected until Friday December 23th, so current hourly rates would probably be less than one. On the morning of maximum, hourly rates of between 5-10 Ursids may be seen. At 33 km/sec. the Ursids produce mostly medium-slow meteors.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately eight 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. Morning rates are 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
ANT Antihelions           06h 36m  +23    30     2     1
MON Monocerotids          07h 03m  +07    41    <1    <1
HYD Sigma Hydrids         08h 54m  +00    61    <1    <1
DLM Dec Leonis Minorids   10h 39m  +31    64     1     1
COM Coma Berenicids       11h 51m  +18    65     1     1
URS Ursida                13h 58m  +76    33    <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

Meteor Activity Outlook for December 3-9, 2011

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.

No matter where you live, the first half of December provides some of the best meteor activity of the year. Unfortunately in 2011, the moon will spoil much of this activity as I reaches its full phase on the 10th. In the northern hemisphere the sporadic rates are still strong plus you can also count on strong activity from the Geminids, which peak on December 14. There are also several minor radiants that add a few meteors each hour. All of these centers of activity are located high in the sky during the early morning hours this time of year. Much of the activity mentioned above can also be seen from the southern hemisphere. While the sporadic rates are not as strong as those seen from the north, they are stronger than the previous months and heading for a maximum in February. The warm, but short summer nights south of the equator make for some great viewing as long as the moon does not interfere.

During this period the moon waxes from half illuminated to nearly full by the end of the period. This weekend the waxing gibbous moon will set during the early morning hours, allowing a few hours of observing under dark skies between moon set and the start of morning twilight. The estimated total hourly rates for evening observers this week is near three as seen from the northern hemisphere and two as seen from the southern hemisphere. For morning observers the estimated total hourly rates should be near twenty two as seen from mid-northern latitudes and eighteen from mid-southern latitudes. 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 December 3/4. 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 December Phoenicids (PHO) are a periodic shower that rarely produces noticeable activity. The only impressive display produced by this shower occurred in 1956 when ZHR’s were near 100. Peak activity occurs on December 6. Little activity is expected away from the peak night. The radiant is currently located at 00:46 (016) -53. This position lies in eastern Phoenix, five degrees northwest of the first magnitude star Archernar (Alpha Eridani). These meteors are best seen near 2000 (8pm) local standard time (LST), when the radiant lies highest above the horizon in a dark sky. Due to the southerly declination of the radiant, this shower is not visible north of the northern tropical areas. The deep southern hemisphere has the best chance of seeing any activity. At 22 km/sec. the Phoenicids produce very slow meteors.

The last of the Northern Taurids (NTA) for 2011 will be seen this week from a large radiant centered at 05:09 (077) +26. This position lies in eastern Taurus, five degrees southwest of the second magnitude star El Nath (Beta Tauri). The radiant is best placed near midnight LST, when it lies highest above the horizon. Since the radiant is large, Northern Taurid meteors may also appear to come from southern Auriga, southeastern Perseus, northern Orion, and western Gemini as well as Taurus. Meteors from the Northern Taurids strike the atmosphere at 29km/sec., which would produce meteors of slow velocity. Expected rates would be near two per hour, no matter your location.

The November Orionids (NOO) were recently discovered by Sirko Molau and Jueregen Rendtel by analyzing video data from the IMO network. For years this radiant was lost in the maze of radiants active this time of year. Due to the low activity, visual observers were unable to detect this shower. This shower is active from November 18 through December 9. Maximum activity occurred on November 30. Once you know the radiant in advance, this shower is actually quite noticeable, producing an average of two shower members per hour near maximum. The radiant is currently located at 06:16 (094) +15. This position lies in northeastern Orion, seven degrees northeast of the orange first magnitude star Betelgeuse (Alpha Orionis). These meteors are best seen near 0100 LST when the radiant lies on the meridian and highest above the horizon. At 44 km/sec. the November Orionids produce mostly medium velocity meteors.

The Monocerotids (MON) are active from December 7th through the 18th. Peak activity occurs on December 8th. On the night of maximum activity the radiant is located at 06:37 (099) +08. This position lies in northern Monoceros, eight degrees south of the second magnitude star Alhena (Gamma Geminorum). Rates at maximum should be near one per hour no matter your location. The Monocerotids are best seen near 0100 LST when the radiant lies highest above the horizon. At 41 km/sec. the Monocerotids produce mostly meteors of medium velocity.

Geminid (GEM) activity begins this weekend from a radiant located at 06:55 (104) +34. This position lies in northern Gemini, near the fourth magnitude star Theta Geminorum. Expected rates this weekend would only be near one per hour as maximum is still ten days away. Although Geminid meteors can be seen all night long, they are best seen near 0200 LST when the radiant lies highest above the horizon. This shower peaks on the night of December 14, when rates can surpass 60 shower members per hour in moonless skies. Unfortunately this year there will be a bright moon and observers will be limited to seeing no more than 20-30 meteors per hour. Geminid activity can be seen from the southern hemisphere but at much reduced rate. As seen from south of the equator, Geminid activity could only be seen for a few hours before and after 0200 LST. At 35 km/sec. the Geminids produce mostly meteors of medium velocity.

The Puppid-Velids (PUP) are a vast complex of weak radiants located in the constellations of Puppis and Vela. Visual plots and photographic studies have revealed many radiants in this area during November and December. The combined strength of these radiants can produce a ZHR of ten. Actual hourly rates will be much less unless you happen to be observing from the deep Southern Hemisphere. Activity from this source begins around December 1st. The center of this activity is currently located at 08:05 (121) -45. This position lies in western Vela, two degrees north of the second magnitude star Gamma Velorum. Peak rates occur near December 7. These meteors are best seen near 0300 LST when the radiant lies highest above the horizon in a dark sky. Observers located in the Southern Hemisphere have an advantage viewing this shower as the radiant will rise higher into their sky allowing more activity to be seen. Since the radiant lies low in the south for most northern hemisphere observers, meteors seen from north of the equator tend to be long in length and long-lasting. At 40 km/sec. the Puppid-Velids produce meteors of average velocity.

The Sigma Hydrids (HYD) are active from November 26 through December 20. Maximum activity occurs on December 6 from a radiant located at 08:11 (122) +03. This position lies on the Hydra/Canis Minor border, seven degrees southeast of the brilliant zero magnitude star Procyon (Alpha Canis Minoris). These meteors are best seen near 0300 LST when the radiant lies highest above the horizon. Current rates would be near two per hour no matter your location. At 61 km/sec. the Sigma Hydrids produce mostly swift meteors.

Activity from the December Leonis Minorids (DLM) begin next week from a radiant located at 09:56 (149) +37. This position lies in central Leo Minor, seven degrees northeast of the fourth magnitude star Alpha Lyncis. These meteors are best seen near 0500 LST when the radiant lies highest above the horizon. This shower peaks on December 20th so current rates would be near one per hour as seen from the northern hemisphere and less than one per hour as seen from south of the equator. At 64 km/sec. the December Leonis Minorids produce mostly swift meteors.

Another shower verified by video means are the Psi Ursa Majorids (PSU). This shower is active from November 29-December 13 with maximum activity occurring on December 5. On Tuesday the radiant is located at 11:07 (167) +43. This position lies in southern Ursa Major, one degree south of the third magnitude star Psi Ursae Majoris. This area of the sky is best placed during the last hour before dawn, when it lies highest above the horizon in a dark sky. Current rates would most likely be less than one per hour. At 61km/sec., the average Psi Ursa Majorid meteor would be swift.

Another shower verified by video means are the December Kappa Draconids (KDR). This shower is active from November 30-December 6 with maximum activity occurring on December 3rd. On the night of maximum the radiant will be located at 12:24 (186) +70. This position lies in extreme western Draco, close to the faint star Kappa Draconis. While the radiant lies above the horizon all night for most of the northern hemisphere, it is best placed during the last hour before dawn, when it lies highest above the horizon in a dark sky. Current rates would most likely be less than one per hour. At 43km/sec., the average December Kappa Draconid meteor would be of medium velocity.

Lastly, the December Alpha Draconids (DAD) are active beginning Sunday from a radiant located at 13:31 (203) +60. This position actually lies in northeastern Ursa Major, five degrees north of the second magnitude double star Mizar (Zeta Ursae Majoris). These meteors are best seen during the last dark hour before dawn, when the radiant lies highest above the horizon in a dark sky. This shower is not well seen from the southern hemisphere. Maximum activity is expected on Monday December 5th, but hourly rates would probably be less than one no matter your location. At 44 km/sec. the Alpha Draconids produce mostly medium speed meteors.

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 six 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 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
PHO Dec Phoenicids        00h 46m  -52    18    <1    <1
NTA Northern Taurids      05h 09m  +26    29     2     2
NOO November Orionids     06h 16m  +15    44     2     2
MON Monocerotids          06h 37m  +08    41     1     1
GEM Geminids              06h 55m  +34    35     1     1
PUP Puppids-Velids        08h 05m  -45    40    <1     2
HYD Sigma Hydrids         08h 11m  +03    61     2     2
DLM Dec Leonis Minorids   09h 56m  +37    64     1    <1
PSU Psi Ursa Majorids     11h 07m  +43    61    <1    <1
KDR Dec Kappa Draconids   12h 24m  +70    43    <1    <1
DAD Dec Alpha Draconids   13h 31m  +60    44    <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