In the Transient Sky – December 2012

December 2012 Highlights
* Geminid meteor shower peaks on the night of December 14/15
* Jupiter bright in the eastern evening sky
* Jupiter and the Moon make a spectacular Christmas pair
* Comet C/2012 K5 (LINEAR) brightens to 8th magnitude

Note: If anyone has pictures or observations of these objects/events and want to share them with my readers, send them to the Transient Sky at <transientsky1@yahoo.com>.

Planets

Evening Planets

Mars - One needs a very clear southeast horizon to catch Mars in the early evening. Glowing at magnitude +1.2 Mars is currently not as bright as other planets. But it is traveling through a patch of sky with few bright stars so it is rather apparent as the brightest, reddest, “star” in that part of the sky. It spends most of the month against the stars of eastern Sagittarius before approaching Capricornus at the end of the month. The Moon passes near Mars on the evening of the 14th.

Jupiter – Jupiter reaches opposition on December 2nd. At that time it is at its brightest (magnitude -2.7) and closest to Earth (4.07 AU). It spends the month slowly retrograding just north of the stars of the Hyades cluster in Taurus. At the start of the month it rises in the northeast at sundown. By the end of the month, it is well up in the eastern sky by nightfall. On Christmas night, the Moon and Jupiter will make a beautiful pair.

Morning Planets

Saturn – Saturn is an early morning object rising around 4:30-5:00 am at the start of the month. By the end of the month, Saturn rises 2 hours earlier.  All month Saturn glows at magnitude +1.3. The Moon passes close to Saturn on the mornings of the 10th.

Venus – Venus rises around 5:00 am on the 1st and 6:00 am on the 31st. In a telescope the planet will appear more than half-illuminated (about 90%). At magnitude -3.8, Venus is by far the brightest ‘star’ in the morning sky.  The Moon passes to the south of Venus on the morning of the 11th. Venus will become more and more difficult to observe over the coming months as it approaches conjunction with the Sun.

Mercury – Mercury is the last of the morning planets to rise. On the 1st it is magnitude -0.2 and rises around 5:30 – 6:00 am. It is still observable peaking above the southeast horizon just before day break through the middle of the month.

Meteors

The year is usually split in 2 with January through June having low rates with few major showers while July through December have high rates with many major showers. Meteor activity is still near an annual maximum this month.

Sporadic Meteors

Sporadic meteors are not part of any known meteor shower. They represent the background flux of meteors. Except for the few days per year when a major shower is active, most meteors that are observed are Sporadics. This is especially true for meteors observed during the evening. During December mornings, 10 or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Geminids (GEM) [Max Date = Dec. 13, Max ZHR = ~120 per hour]

The night of December 13/14 will bring the peak the Geminids, one of the year’s better meteor showers. It’s usually a toss up as to which is better, the Perseids of August or the Geminids, though lately the Geminids have been routinely out-producing the Perseids. If the sky is clear it will provide one of the few nights of the year when it’s almost guaranteed that you will be able to observe a meteor after about 10-20 minutes of observing.

From a dark, moon-less sky, the Geminids have been known to consistently produce rates of over 100 meteors per hour at their peak. Unlike most showers that can only be observed in the early hours of the morning, the Geminids can be seen in good numbers as early as 10 pm and are great anytime after midnight. The Geminids will appear to radiate from the constellation of Gemini near the bright star Castor.

According to analysis of meteor video data by Sirko Molau, the Geminids are active for almost an entire month between the dates of November 23 and December 21. Though high rates are only possible within a few days of the peak.

The International Meteor Organization (IMO) has a “live” graph showing the rate of the Geminids as reported by visual observers around the world.

Most meteor showers are produced by comets with orbits that extend out to the orbit of Jupiter or beyond. The Geminids are different. They are on a very short uncomet-like orbit that extends from a very close 0.14 AU from the Sun to a not so far 2.40 AU.

1) Phaethon could be a comet whose original orbit evolved into its current one after many millennia of close approaches with the inner planets. Some models of the formation of the Geminids require the shower particles to be released over many centuries to millennia. This is consistent with the behavior of a comet.

2) Phaethon may be a Main-Belt comet. Main-Belt comets are objects that originate in the outer Asteroid, or Main, Belt. Since they contain a sizable fraction of volatile material (water, carbon monoxide, etc.), they can occasionally exhibit cometary activity. Four of these objects have been observed to display cometary activity in the Main Belt. Since they start on asteroid orbits, it is not too difficult for one of them to find itself on an orbit similar to Phaethon.

3) Phaethon is an asteroid that broke up in the past. There is evidence to suggest that Phaethon is just the largest piece of a past break-up. In fact, two additional asteroids that may once have been a part of Phaethon have been found, (155140) 2005 UD and 1999 YC. According to Peter Jennisken’s book “Meteor Showers and Their Parent Comets”, the Geminids can be explained by the break-up of Phaethon just after perihelion many orbits ago. Since Phaethon gets to within 0.14 AU (14% of the Earth-Sun distance), perhaps it split under the intense solar heat. BTW, this scenario does not rule out Phaethon as a ice-rich Main-Belt comet.

The recent discovery of additional asteroids related to Phaethon points to scenario 3 as the most likely origin of the Geminids. If true, the Geminids were not the result of long-term cometary activity like most meteor showers but were created in a single event when Phaethon split or shed a smaller piece. The Daytime Sextentids and perhaps the very minor Canis Minorids were created by even older break-up events.

The video below contains 159 meteors detected by my SALSA3 camera during the 2010 Geminids peak over Tucson. It starts in the evening where you can catch a short glimpse of the Moon as it quickly moves out of the frame. Note the top of one of my trees illuminated by Christmas lights for the first few meteors. Though not all of the meteors are Geminids most are and it is fun to watch them radiate from the twin stars of Castor and Pollux.

GEMS

Minor Meteor Showers

Minor showers produce so few meteors that they are hard to notice above the background of regular meteors. Info on many minor showers are provided on a weekly basis by Robert Lunsford’s Meteor Activity Outlook.

Additional information on these showers and other minor showers not included here can be found at the International Meteor Organization’s 2012 Meteor Shower Calendar.

Comets

Naked Eye Comets (V < 6.0)

None this month.

Binocular Comets (V = 6.0 – 8.0)

None this month

Small Telescope Comets (V = 8.0 – 10.0)

C/2012 K5 (LINEAR)

This is a long-period comet discovered by the LINEAR near-Earth asteroid survey program on May 25, 2012. At the time the comet was around magnitude 17-18. Though it passed through perihelion on Nov. 28 at a distance of 1.14 AU, the comet will become brighter this month as it rapidly approaches the Earth. Close approach will occur at the very end of December at a distance of 0.29 AU (27 million miles or 44 million km).

Recent visual observations place the comet around magnitude 10.0 at the end of November. The comet should brighten by another 2 magnitudes by the end of December. This month it is primarily a northern hemisphere object and spends much of the month running the length of the Big Dipper from the handle to the bowl before rocketing southward through the rest of Ursa Major into Lynx. The fact that it spends the first 3 weeks of the month among the familiar stars of the Big Dipper should aid many people in seeing the comet.

The comet starts the month as a small telescope object but by the middle of the month it should be visible in binoculars for observers under a dark sky. For bright sky observers a small telescope may still be needed.

I did observe the comet back on Oct. 21 with the University of Arizona’s Kuiper 1.5-m telescope. Though still over a month from perihelion and located low in the sky, the comet displayed an impressive tail and even some near-nucleus jet activity.

C2012K5_2012Nov21

Ephemeris for C/2012 K5 (LINEAR)
Date            RA        DEC    Delta   r   Elong    V
2012 Dec 01   14h 03m  +45d 41'  0.881 1.142   75    9.9
2012 Dec 11   13h 33m  +50d 48'  0.643 1.158   88    9.3
2012 Dec 21   11h 53m  +60d 05'  0.418 1.196  110    8.7
2012 Dec 31   06h 48m  +49d 48'  0.294 1.253  153    8.0

RA = Right Ascension, DEC = Declination, Delta = distance from Earth in AU
r = distance from the Sun in AU, Elong = elongation from Sun in degrees
V = Visual magnitude

Meteor Activity Outlook for December 1-7, 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 last quarter phase on Thursday December 6th. At this time the moon is located ninety degrees west of the sun and rises near 2300 (11pm) local standard time (LST). This weekend the waning gibbous moon will rise during the early evening hours and will effectively spoil the sky the remainder of the night with its intense lunar glare. 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 twelve from the mid-northern hemisphere and seven 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 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 1/2. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

Details of each active shower will return next week when the observing conditions improve.

The following radiants are expected to be active this week.  Rates and positions are exact for Saturday night/Sunday morning .

Dec. Phoenicids (PHO) – 01:00 (015) -53    Velocity – 18km/sec.
Northern Hemisphere – <1 per hr.    Southern Hemisphere – <1 per hr.

Andromedids (AND) – 01:28 (022) +55   Velocity – 19km/sec.
Northern Hemisphere – <1 per hr.   Southern Hemisphere – <1 per hr.

Northern Taurids (NTA) – 05:03 (076) +26   Velocity – 29km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – <1 per hr.

November Orionids (NOO) – 06:10 (093) +15   Velocity – 44km/sec.
Northern Hemisphere – 2 per hr.   Southern Hemisphere – 1 per hr.

Geminids (GEM) – 06:47 (102) +34   Velocity – 35km/sec.
Northern Hemisphere – 1 per hr.   Southern Hemisphere – <1 per hr.

Puppid-Velids (PUP) – 08:00 (120) -45   Velocity – 40km/sec.
Northern Hemisphere – <1 per hr. Southern Hemisphere – 1 per hr.

Sigma Hydrids (HYD)  – 08:04 (121) +04   Velocity – 61km/sec.
Northern Hemisphere – 1 per hr. Southern Hemisphere – 1 per hr.

Dec. Kappa Draconids (DKD) – 12:17 (184) +71   Velocity – 43km/sec.
Northern Hemisphere -<1 per hr. Southern Hemisphere – <1 per hr.

Clear Skies!
Robert Lunsford
American Meteor Society

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

Meteor Activity Outlook for December 18-24, 2010

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

No matter where you live, the first half of December provides some of the best meteor activity of the year. 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 January. 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 Tuesday December 21st. At this time the moon lies opposite the sun and is above the horizon all night long from most locations. This is the worst time to attempt to view meteor activity as the bright moonlight will obscure all but the brightest meteors. The estimated total hourly rates for evening observers this week is ~3 from the northern hemisphere and ~2 for observers south of the equator. For morning observers the estimated total hourly rates should be ~10 from the northern hemisphere and ~9 as seen from the southern hemisphere. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity. 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 December 18/19. 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 detailed descriptions will be continued next week when the moonlight is not as intense.

Shower Name                 RA     DEC   Vel     Rates
                                         km/s   NH    SH
ANT Antihelions           06h 40m  +23    30     2     2
MON Monocerotids          07h 08m  +07    41    <1    <1
GEM Geminids              07h 56m  +31    35     1     1
HYD Sigma Hydrids         08h 56m  +00    61    <1    <1
DLM Dec Leonis Minorids   10h 44m  +31    71     1    <1
COM Coma Berenicids       11h 48m  +18    65     2    <1
URS Ursids                14h 12m  +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

Dec 15/16 Meteors

Two nights ago my cameras detected a total of 206 Geminids (some were probably duplicates). One night ago the total number dropped to 32 Geminids. Last night the number of Geminids was a whopping 2. It’s amazing how quickly the Geminids can fall off after their peak. It is safe to say that the 2010 Geminids are pretty much over for visual observers.

Last night marked SALSA3’s 82nd straight night with a meteor detection. With it currently raining and more forecast for tonight the streak may very well end at 82.

Obs  Date(UT)      Time    TOT SPO ANT GEM HYD DAD DLM MON COM
SAL3 2010-12-16   05h 54m   19  10  1   0   2   1   3   1   1
ALLS 2010-12-16   04h 58m   19  12  1   2   1   1   2   0   0
HERM 2010-12-16   11h 31m   9   7   0   1   1   -   -   0   0

SAL3 - SALSA3 camera in Tucson (Carl Hergenrother)
ALLS - Near all-sky camera in Tucson (Carl Hergenrother)
VIST - Visual observations from Tucson (Carl Hergenrother)
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   
GEM - Geminids
HYD - Sigma Hydrids
DAD - December Alpha Draconids
DLM - December Leonis Minorids
MON - Monocerotids

Dec 14/15 Meteors (night after the Geminids peak)

What a difference 24 hours makes! Only a day removed from the Geminids peak and rates have crashed to a fraction of their peak. During the past 5 nights SALSA3 detected 12, 22, 69, 124 and now 20 Geminids. This is a characteristic of the Geminids in that the post-peak rates fall off much more rapidly than the pre-peak increase.

The night of Dec 14/15 marked the 81st consecutive nights that SALSA3 detected a meteor. As of right now, there is a good chance that it is clear enough for night 82 to produce a few meteors. Tomorrow night will be iffy as a storm, our first in 2 months, is forecast to bring rain and clouds to the area. Will the streak survive? We’ll have to wait and see.

Obs  Date(UT)      Time    TOT SPO ANT GEM HYD PUP DAD DLM MON COM
SAL3 2010-12-15   12h 10m   53  20  5   20  1   1   1   1   2   2
ALLS 2010-12-15   12h 38m   40  15  4   11  3   0   1   3   1   2
HERM 2010-12-15   11h 50m   28  15  2   10  0   1   -   -   -   0
VISM 2010-12-15   02h 00m   37  0   1   28  3   1   -   -   1   3 (LM = +5.7 to +6.0)

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   
GEM - Geminids
HYD - Sigma Hydrids
PUP - Puppids-Vellids
DAD - December Alpha Draconids
DLM - December Leonis Minorids
MON - Monocerotids

Dec 13/14 Meteors and the Geminids Peak

The Geminids did not dissapoint! Though the IMO ZHR Live page doesn’t seem to be updating observations made by myself and Salvador show ZHRs that equaled or even exceeded the expected value of 120. Over the course of about 3.33 hours I averaged about 1 meteor per minute under skies that range from a limiting magnitude of +5.0 (when the Moon was still up) to +5.7 (before the break of dawn).

For my SALSA3 and Sentinel cameras it was a record-setting night. The previous single night record for SALSA3 (and its 2 predecessors) was 124 meteors during this year’s Perseids peak. Last night SALSA3 detected 124 Geminids! Add in another 35 non-Geminids and the total for he night was 159 meteors. The near-allsky Sentinel also broke its previous record set during this year’s Perseids by catching 123 meteors of which 84 were Geminids.

The video below contains all 159 meteors detected by SALSA3. It starts in the evening where you can catch a short glimpse of the Moon as it quickly moves out of the frame. Note the top of one of my trees illuminated by Christmas lights for the first few meteors. Though not all of the meteors are Geminids most are and it is fun to watch them radiate from the twin stars of Castor and Pollux.

The next plot is a radiant plot. For every meteor detected my SALSA3, the MetRec software runs the path of the meteor back. Where the back tracks of related meteors cross is the radiant. It is obvious from the plot that most of last night’s meteors are related and radiated from an area near the bright star Castor.

Down in Hermosillo, Salvador spent almost 5 hours watching the Geminids and racked up a total of 308 meteors of which 272 were Geminids. This is in addition to his PARENI camera which also caught 75 meteors.

Obs  Date(UT)      Time    TOT SPO ANT GEM HYD PUP DAD DLM MON COM
SAL3 2010-12-14   12h 10m  159  22  7  124  2   0   2   1   0   1
ALLS 2010-12-14   12h 38m  123  24  9   84  1   1   0   1   2   1
HERM 2010-12-14   11h 42m   75  17  6   49  1   -   -   -   1   1
VIST 2010-12-13   03h 20m  199  31  -  168  -   -   -   -   -   - (LM=+5.0 to +5.7)
VISH 2010-12-13   04h 40m  308  12  3  272  8   4   -   -   5   4 (LM=+5.5 to +6.2)

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   
GEM - Geminids
HYD - Sigma Hydrids
PUP - Puppids-Vellids
DAD - December Alpha Draconids
DLM - December Leonis Minorids
MON - Monocerotids
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