In the Transient Sky – January 2012
January 3, 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 <email@example.com>.
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.
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.
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 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.
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.
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)