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

Quadrantid Meteors to Peak Tonight

Tonight the first major meteor shower of 2012 is scheduled to peak in intensity. The Quadrantids (QUA) are often missed shower due to their short duration of high activity and the fact that they peak in the middle of NH winter. Hence it is easy to miss the peak especially if it is bitterly cold outside.

This year the QUA are scheduled to peak around ~7:20 UT on the night of January 4. This works out to be 2:20 EST, 1:20 CST, 12:20 MST and 11:20 PST. Still recent years suggest rates should be near maximum for 4-6 hours on either side of the peak so observers from Europe to North America have a good chance of seeing a nice show. The waxing gibbous Moon sets after 3 am which is nearly perfect since the radiant of the QUA is only then getting high enough to easily observe. It is best to dress warm and catch the Quadrantids during the last 3 hours or so of the night. Meteors will appear to radiate from the northeast. Live reports and activity rates can be found at the IMO’s Live ZHR page.

The Quadrantids are named after the constellation that meteors appear to radiate from. But unlike the rest of the meteor showers, the Quadrantids are named after a constellation that is no longer recognized as official, Quadrans Muralis. Nowadays this patch of the sky is located in northern Boötes.

Most meteor showers are the result of dust released from comets. The Quadrantids are probably no different even though the only object that matches their orbit is an asteroid named 2003 EH1. It is likely that EH1 was an active comet in the past and their is evidence that is was observed as a comet back in 1490.

For the past 2-3 years I have operated a meteor camera system (the SALSA system). Due to a recent move to a new home, the system is still boxed up till I figure out where to place it. Hopefully the SALSA camera will be back online in the next few weeks. In the meantime I plan to watch the QUA the old fashion way from my new and darker :) backyard.

In the Transient Sky – January 2012

This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of January 2012.

January 2012 Highlights
* Venus and Jupiter share the evening sky
* Comet C/2011 W3 (Lovejoy) remains a nice, though fading, naked eye object for southern observers
* Comet C/2009 P1 (Garradd) is a nice binocular object during the morning
* Quadrantid meteor shower peaks on the 4th

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

Venus – Venus is the brilliant beacon in the southwest after sunset. As bright as Venus is it will only get brighter and higher in the sky for the remainder of the winter and into the spring. This year’s evening apparition is as good as it gets with peak visibility in March/April. The real showstopper occurs at the end of the apparition in June when Venus will transit the disk of the Sun. 2012 marks the last Venus transit till 2117. The Moon pairs up with Venus on the evenings of 25th and 26th.

Jupiter -  The King of Planets shares the evening sky with Venus. It is high in the southeast sky at the end of evening twilight. Past its late October opposition occurred it will slowly fade from magnitude -2.6 to -2.3. This month it resumes moving prograde through the constellation of Aries. Not that you’ll need the Moon to find Jupiter but the two will make a nice pair on the nights of the 1st-3rd and 29th-30th.

Morning Planets

Mars - With opposition in March 2012, Mars double in brightness (magnitude +0.2 to -0.5) as it begins to retrograde near the Leo-Virgo border. Mars rises around 11 pm on the 1st and 9 pm on the 31st. The Moon pairs up with Mars on the mornings of the 12th and 13th.

Saturn - Saturn rises 3 hours after Mars. At magnitude +0.7 Saturn will be located ~6-7° to the lower right of the slightly fainter star Spica in Virgo (magnitude +1.0). The Moon visits on the morning of the 16th.

Mercury – Mercury starts off the new year at  the tail end of a rather good morning apparition. By mid-month it has sunk back into the glow of dawn.

Meteors

Meteor activity starts off high at the beginning of the month but then drops quickly as the month prgresses. 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.

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 January mornings, 10 or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Quadrantids (QUA)[Max Date = Jan 4, Max ZHR = ~60-200 per hour]

The Quadrantids are the best shower that you’ve probably never heard of. It’s bad enough that this shower peaks in the middle of winter in the northern hemisphere, but it is also named after a long defunct constellation. When first identified in the early 1800s, the meteors were observed to radiate from the small faint constellation of Quadrans Muralis (the Mural Quadrant). Unfortunately, the constellation didn’t make the cut when the official list of 80 constellations was set in 1930. Today, Quadrans Muralis and the radiant of the Quadrantids can be found on the northern reaches of the constellation Bootes.

Another strike against observing the Quadrantids is their short duration. Most showers, like the Perseids and Orionids, produce high rates of meteors for a few days near their maximum. The Quadrantids are only highly active for 12-24 hours. As a result, the shower can be missed if the peak does not coincide with your early morning observing.

The peak time for this shower is always uncertain on the order of half a day or so and the IMO prediction calls for a peak at 7:20 UT on Jan 4 though this time could be off be 12 hours or more. Observers in Europe and the Americas will be well placed for seeing this year’s peak. Unfortunately observers south of the Equator will not see much from the Quadrantids.

Back in 2009 this shower put on a great show with the peak well observed from the US. Peak rates that year reached a ZHR of ~150-160. But in 2008 and 2011, rates “only” reached into the 80s. The Moon will be a problem until it sets around 3 am. Then again the radiant only gets high enough for easy observing after 3 am so the Moon is not much of a problem.

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)

C/2011 W3 (Lovejoy)

The Surprise Comet of 2011 proved the experts wrong and became the most spectacular comet since Comet C/2006 P1 (McNaught) in 2007. Terry Lovejoy is no stranger to new comets and C/2011 W3 marks his 3rd comet discovery. The Australian amateur used an 8″ telescope and CCD camera to first spot the comet on November 27. Though a diffuse relatively faint 11-12th magnitude object at discovery it was rapidly approaching the Sun. In fact, Comet Lovejoy is a member of the Kreutz sungrazing family of comets which can pass extremely close to the Sun. A small number of Kreutz sungrazers have been seen from the ground over the past 1000 years and a few have ranked as some of the best comets of all time (1106, 1843, 1880, 1882, 1887, 1965). The last Kreutz to be seen from the ground was Comet White-Ortiz-Bolelli in 1970. Since then over 2000 faint “pygmy” sungrazers have been observed close to the Sun by Sun-watching spacecraft.

Based on the apparent faintness of C/Lovejoy as it approached perihelion on December 16 at a distance of only 87,000 miles (140,000 km), it was not expected to survive long past perihelion. Surprisingly the comet did survive after showing some odd behavior near the Sun (comet appeared to fade at perihelion only to rebrighten hours later also it appeared to loss its tail until a new one formed). Due to the orientation of its orbit relative to Earth, the comet is currently only observable from the Southern Hemisphere. A number of southern observers were able to see the comet as a brilliant long tailed object of negative magnitude. Even now the tail is being reported between 20 and 40° in length. The head has rapidly faded suggesting the nucleus has either decreased greatly in activity or even broken up.

Racing away from the Sun the comet will travel across a large swatch of the southern sky this month. For northern observers we may have a chance to see what’s left of Lovejoy towards the end of the month as the comet moves north through the dim constellations of Pictor and Caelum.

Here’s Comet Lovejoy in all its glory as seen from the International Space Station and imaged by astronaut Dan Burbank.

Comet Lovejoy is visible near Earth's horizon in this nighttime image photographed by NASA astronaut Dan Burbank, Expedition 30 commander, onboard the International Space Station on Dec. 22, 2011. Credit: NASA/Dan Burbank.

Additional photos of Comet Lovejoy can be found at the sites of Seiichi Yoshida, Astronomical Society of Victoria, and Cometography (Gary Kronk).

Binocular Comets (V = 6.0 – 8.0)

C/2009 P1 (Garradd)

Until the arrival of Comet Lovejoy, Comet C/2009 P1 (Garradd) held the title of brightest comet of 2011.  First seen way back on August 13, 2009 by Gordon Garradd who was observing for the Siding Spring Survey, a NASA-funded survey observing from Australia. At the time of discovery it was located at a distance 8.7 AU from the Sun, nearly the distance of Saturn. Perihelion occured 2 days before Christmas 2011 at 1.55 AU from the Sun. Though the comet does not get very close to the Sun, it is an intrinsically bright comet and is already a borderline naked eye object for observers at very dark sites. I was able to observe the comet on the morning of January 2, 2012 with 10×50 binoculars and estimated its brightness at magnitude 6.7.

The comet starts the month at a distance of 1.56 AU from the Sun and 1.94 AU from Earth. At mid-month it is 1.58 AU from the Sun and 1.76 AU from Earth and by month’s end it will be 1.64 and 1.56 AU from the Sun and Earth, respectively.  Though the comet is post-perihelion and moving away from the Sun, it is also moving closer to Earth. As a result, the comet should brighten a little more this month.

Traveling north to the left of the ‘keyhole’ of Hercules, Comet Garradd is an early morning object this month.

Date       RA       DEC     Delta    r    Elong   Mag
Jan 1    17h 30m  +26°50'   1.936  1.555    53    6.6
Jan 16   17h 27m  +32°23'   1.762  1.584    63    6.5
Jan 30   17h 18m  +40°37'   1.561  1.638    76    6.4

Small Telescope Comets (V = 8.0 – 10.0)

None

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
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