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In the Sky This Month – January 2009 January 1, 2009

Posted by Carl Hergenrother in Asteroids, Comets, Meteors, planets.
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This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of January 2009. The month starts off with Mercury and Jupiter close together in the evening sky. January also has one major meteor shower, the Quadrantids on Jan 3/4.

Note: If anyone has pictures or observations of these objects/events and want to share them, send me a comment. I’ll post them here.

Planets

Venus rules the month of January. Located about 30-40 degrees above the southwest horizon, Venus is the brightest “star” in the sky for the first few hours of the night. Through a telescope, Venus appears like a brilliant half moon. The Moon will pass within 2.5 degrees of Venus on the night of the 30th.

Jupiter is located well below Venus in the west-southwest during the first week of January. After that Jupiter will be too close to the Sun to be seen.

Mercury is also visible a few degrees above Jupiter during the 1st week or so of January. It will be furthest from the Sun on the 4th and highest above the horizon on the 6th. By mid-month, Mercury will be too close to the Sun to be seen.

This month Saturn rises in the east around 11pm on the 1st and 9pm on the 31st. The best time to observe it, though, is when it is located directly overhead (5am on the 1st and 3am on the 31st). The Moon will pass close to Saturn on the night of the 15th.

Mars is still too close to the Sun to be seen.

Meteors

The month of January experiences 1 major shower, the Quadrantids, and only a few minor ones.

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 November, six (6) or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Quadrantids (QUA)

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 north of the constellation of Bootes.

Another strike against observing the Quadrantids is their short duration. 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.

This year there are 2 predictions for the peak. Based on past Quadrantid peaks, the International Meteor Organization predicts a peak on January 3 at 12h 50m UT. That’s 5:50 am MST or 4:50 am PST. If this prediction is correct, the Quadrantids will be best over western North America and probably pretty good for all of North America.

A second prediction is based on work by Jeremie Veubaillon and published in a chart in Peter Jenniskens’s book “Meteor Showers and Their Parent Comets”.It predicts an earlier peak on January 3 at ~1:00 UT. That’s in the early evening for North America at a time when the shower will not be easily visible. The Veubaillon prediction is based on all of the Quadrantids having been released during the break-up of a comet in 1490.

Last year rates reached as high as ~80 meteors per hour under a dark sky. Like most meteor showers, the Quadrantids are only observable early in the morning a few hours before dawn. The International Meteor Organization will post up-to-date observations of the activity level at their ZHR Live site.

Where do the Quadrantids come from? According to Peter Jenniskens, the Quadrantids are the result of an outburst of material or even the break-up of a comet in 1490. This comet was observed by Chinese, Korean and Japanese astronomers. In 2003, a new asteroid was discovered named 2003 EH1. It now appears that 2003 EH1 is either the same as the comet seen in 1490 or the largest surviving piece of that comet.

Minor Meteor Showers

Minor showers produce so few meteors that they are hard to notice above the background of regular meteors.

Coma Berenicids (COM)

The Coma Berenicids are a minor shower with rates of ~5 meteors per hour at their peak. The shower is active from mid-December to late January as its radiant moves from southern Ursa Major through Coma Berenices and into Virgo. The shower may have been created by Comet C/1913 I (Lowe) a retrograde Halley-type comet. That is assuming Comet Lowe ever existed. There are some doubts that the comet was real since other observers were not able to observe the comet.

According to Peter Jennisken’s book “Meteor Showers and Their Parent Comets” a number of meteor outbursts seen between the years of 609 AD and 764 AD may have caused by this shower.

Additional information on these showers and other minor showers not included here can be found at the following sites: Robert Lunsford’s Meteor Activity Outlook, Wayne Hally’s and Mark Davis’s NAMN Notes, and the International Meteor Organization’s 2008 Meteor Shower Calendar.

Comets

Naked Eye Comets (V < 6.0)

There are no comets bright enough to be seen without binoculars or a telescope.

Binocular Comets (V < 8.0)

Comet C/2007 N3 (Lulin)

The brightest comet of the month can be seen low in the southeast right before dawn. Starting the month near the “head” of Scorpius, the comet will move into and cross the constellation of Libra during the month. Comet Lulin was discovered by the Lulin Sky Survey in Taiwan on 2007 July 11. At the time the comet was located beyond the orbit of Jupiter.

The comet will be closest to the Sun on 2009 January 10 at 1.21 AU from the Sun. It will be closest to Earth in late-February when it will be only 0.41 AU from us. At that time the comet may be as bright as 4th magnitude making it an easy object for binoculars and small telescopes. In fact, the comet will be visible to the naked eye as a small faint fuzzball from dark sites.

The comet is currently around magnitude 7.5 which makes it an easy object for binoculars and small telescopes from a dark sky. By the end of the month, it should be around magnitude 6 and perhaps visible to naked eye observers in very dark skies.

A finder chart for Comet Lulin can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Small Telescope Comets (V < 10.0)

Comet C/2006 W3 (Christensen)

This comet was discovered over 2 years ago on 2006 November 18 by Eric Christensen of the Catalina Sky Survey north of Tucson. At the time the comet was located at 8.7 AU from the Sun which is nearly the distance of Saturn. The comet continues to move closer to the Sun and Earth and is currently 3.8 AU from the Sun and 3.4 AU from the Earth.

The comet is currently around magnitude 10.2 and will slowly brighten during the month.  It will be traveling south through the constellation of Lacerta and is nicely positioned for evening observing. I was able to observe the comet visually with my backyard 12″ reflecting telescope in November. Being small and condensed, the comet was fairly easy to see.

The comet will continue to brighten as it approaches perihelion at a still rather distant 3.12 AU from the Sun on 2009 July 6. At the time, the comet will be 8th magnitude and visible in many smaller backyard telescopes and even binoculars from dark sites. Christensen should remain bright enough to see in modest sized backyard telescopes for all of 2009.

A finder chart for Comet Christensen can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Comet C/2006 OF2 (Broughton)

Similar to Comet C/2006 W3 (Christensen), C/2006 OF2 (Broughton) is another intrinsically bright comet with a large perihelion distance. It was the 2nd comet discovered by amateur astronomer John Broughton of Queensland, Australia. He first saw it on 2006 July 17 with a CCD-equipped 0.25-m telescope. At first, no cometary activity was detected and the object was classified as an asteroid. In late September of 2006, I was able to find evidence of cometary activity on images taken with the University of Arizona 1.54-m and the object was reclassified as a comet.

Comet Broughton passed perihelion on 2008 September 15 at a distance of 2.43 AU from the Sun. Based on its prior brightness behavior, it was not expected to be brighter than 10th magnitude. In the past few weeks, the comet has experienced a minor outburst in brightness. At its current magnitude of 9.8, the comet can be seen in large backyard telescopes. Moving south through the constellation of Auriga, the comet should fade as it moves away from both the Sun and Earth.

A finder chart for Comet Broughten can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Comet 144P/Kushida

Comet Kushida was discovered by Japanese amateur astronomer Yoshio Kushida back on 1994 January 8. With an orbital period of 7.6 years, this year marks its 3rd appearance since discovery.

The comet was not expected to get brighter than magnitude 10 or 11 but recently observers have estimated it is as bright as magnitude 8.8. With perihelion this January 26 at 1.44 AU from the Sun, the comet may brighten a little more over the next few weeks. It is currently retrograding through western Taurus.

A finder chart for Comet Kushida can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Comet 210P/Christensen

Yet another comet discovered by Eric Christensen may be visible in backyard scopes in January. This comet is a short-period comet with a period of 5.7 years. It is very faint except when close to the Sun. Perihelion occurred on December 19 at a distance of 0.53 AU from the Sun.

Alan Watson found Comet 210P/Christensen on images taken by the STEREO-B spacecraft on 2008 December 8 and 9. At the time, he thought the comet might be new until Maik Meyer suggested the STEREO comet was actually Comet 210P/Christensen. STEREO (which stands for Solar TErrestrial RElations Observatory) is a NASA mission to study the Sun and its immediate environment. Though not designed specifically to observe comets, its cameras have the ability to pick up bright comets close to the Sun. Quite often, these comets are too close to the Sun to be seen from Earth due to the scattering of sunlight by Earth’s atmosphere.

Though too close to the Sun to be seen from Earth, another spacecraft was able to see the comet as it sped past the Sun. Observations by the SOHO spacecraft estimated that the comet reached a brightness of 6th magnitude. The comet may still be bright enough for large backyard telescopes during the 1st half of January. The comet should be 9th-10th magnitude as it speeds through the constellation of Ophiuchus in the pre-dawn sky.

Asteroids

Binocular and Small Telescope Asteroids (V < 10.0)

(1) Ceres

Ceres is the biggest asteroid in the Main Belt with a diameter of 585 miles or 975 km. It is so big that it is now considered a Dwarf Planet. Classified as a carbonaceous (carbon-rich) Cg-type asteroid, there are suggestions that it may be rich in volatile material such as water. Some even propose that an ocean exists below the surface. Ceres is one of two targets for NASA’s Dawn spacecraft which is scheduled to visit it in 2015. This month Ceres is located in Leo brightening from magnitude 7.9to 7.2.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand. Finder chart for Ceres from Heavens Above.

(2) Pallas

Pallas is also a carbonaceous asteroid though with a slightly bluish B-type spectrum. Due to its high inclination (tilt of its orbit with respect to Earth’s orbit) of 34 degrees it is a difficult target for future spacecraft missions. Pallas is large with dimensions of 350×334x301 miles or 582×556x501 km. This month it moves through the far southern constellations of Caelum and Eridanus. It fades from  magnitude 8.0 to 8.2 over the course of the month.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand. Finder chart for Pallas from Heavens Above.

(4) Vesta

Though not as large as Ceres, Vesta is more reflective making it the brightest asteroid in the Main Belt. Vesta is peculiar in that it appears to have evidence of volcanism on its surface. Similar to the Moon, Vesta may be covered with large expanses of frozen lava flows. It is classified as a V-type asteroid and is the only large asteroid with this classification. Many of the smaller V-type asteroids are chips of Vesta blasted off it by past asteroid and comet impacts. Vesta is similar in size to Pallas with dimensions of 347×336x275 miles or 578×560×458 km. Vesta will also be visited by NASA’s Dawn spacecraft which will arrive in 2010. On October 30, Vesta was at opposition (directly opposite from the Sun in the sky) and at its brightest. This month Vesta will fade from magnitude 7.6 to 8.1 as it moves from Pisces into Cetus.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand. Finder chart for Vesta from Heavens Above.

(27) Euterpe

Euterpe was the 27th asteroid discovered when it was first seen in 1853. It is an S-type asteroid with a stoney or silicate composition. With a diameter of 75 miles (125 km) it much smaller than Ceres, Pallas or Vesta. The reason it can get as bright as them is due to its orbit which brings it closer to the Sun and Earth. This month Euterpe will be roughly 1 AU from Earth and 2 AU from the Sun.

This month Euterpe will brighten from magnitude 9.7 to 8.9 as it moves from Leo into Cancer. The asteroid will be at its brightest in early February at magnitude 8.8.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand. Finder chart for Euterpe from Heavens Above.

(40) Harmonia

[Thanks to Sam Millar for calling attention to this asteroid.]

Harmonia just barely makes the cut this month. Starting the month at magnitude 9.9, it peaks in brightness on January 12 at 9.5. By the end of the month, Harmonia is back below 10th magnitude.

Similar to Euterpe, Harmonia is a stoney silicate-rich S-type in the inner Main Belt. At opposition on the 12th, it will be 2.30 AU from the Sun and 1.31 AU from Earth.

Finder chart for Harmonia from Heavens Above.

Comets in the News – Dec 17 December 17, 2008

Posted by Carl Hergenrother in Comets.
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The poor weather in AZ and CA have made meteor observing difficult the past few nights. The forecast is for more of the same until at least Friday. In the meantime, this gives me the opportunity to catch up on some comet news.

The past few weeks saw the discovery of 2 new comets and the recovery of a 2 comets on their first return. If you are wondering, Comet Boethin still remains lost (that is if it still exists). For the background story on Boethin, check out the “Where, O Where Has Comet Boethin Gone? : The Case of the Missing Comet” post.

New Discovery – Comet P/2008 X1 (Hill)

Rik Hill of the Catalina Sky Survey used the Catalina 0.68-m Schmidt telescope to discover a comet on 2008 December 4 UT. Comet P/2008 X1 (Hill) is a Jupiter family short-period comet which takes ~6.8 years to orbit the Sun. This is Rik’s 6th comet discovery this year and his 13th overall.

The comet is currently located at opposition in the constellation of Orion. Even though perihelion is not till next May 11, the comet will fade from its current 17th magnitude as it moves away from the Earth. Due to its faintness, the comet can only be observed with astronomical CCD cameras.

p2008x1_hill_orbit

Orbit and location of Comet P/2008 X1 (Hill) and the planets on 2008 December 9. Orbit diagram created by 'C2A for Windows' (http://www.astrosurf.com/c2a)

New Discovery – Comet C/2008 X3 (LINEAR)

The LINEAR (Lincoln Laboratory Near Earth Asteroid Research) survey discovered its 186th comet on 2008 December 4 UT. The faint 17th magnitude comet was found in the constellation Virgo. The comet, designated C/2008 X3 (LINEAR), is a long-period comet having passed perihelion back on October 11. With an inclination of 66 degrees, the comet’s orbit is almost perpendicular to the orbits of the planets. As can be seen in the orbit diagram below, the comet is currently heading south through the plane of the ecliptic. Similar to the Comet Hill, Comet LINEAR is currently at its brightest and will only be observable with a CCD camera.

c2008x3_linear_orbit

Orbit and location of Comet P/2008 X3 (LINEAR) and the planets on 2008 December 9. Orbit diagram created by 'C2A for Windows' (http://www.astrosurf.com/c2a)

Recovery – Comet 209P/LINEAR = P/2004 CB = P/2008 X2

Gary Hug of Scranton, Kansas recovered comet P/2004 CB (LINEAR) on the nights of 2008 December 4 and 5 UT. Gary used a 0.56-m reflector to find the very faint 19th magnitude comet. This Comet LINEAR is a Jupiter family short-period comet on a ~5 year orbit.

P/2004 CB (LINEAR) was discovered by the LINEAR survey back on 2004 February 3 UT. After recovery, the comet is given a new designation, in this case, P/2008 X2 (LINEAR). Since the comet has been observed at two separate returns, it will be numbered and become officially known as Comet 209P/LINEAR. At this point the designation/name changing stops and the comet will go by 209P/LINEAR from now on.

On this return, the comet should brighten to magnitude 15 as it approaches perihelion on 2009 April 15 at 0.91 AU from the Sun. Since 1 AU is the average distance between the Earth and the Sun, Comet LINEAR will be closer to the Sun than the Earth ever gets.

Things will get real interesting when the comet makes its next perihelion passage in 2014. The comet will approach within 0.055 AU (5.1 million miles or 8.2 million km) of the Earth on 2014 May 29 UT. Unfortunately, this is an intrinsically faint comet and may not even get bright enough to be seen in large backyard telescopes without CCD imagers.

Luckily, you may not need a telescope at all to see pieces of this comet. According to predictions by Esko Lyytinen published in Peter Jennisken’s book “Meteor Showers and Their Parent Comets”, a new meteor shower may be visible on the night of 2014 May 24. On that night, the Earth will encounter dust released by 209P/LINEAR during the 1800s and 1900s. How many meteors will be seen is unknown, though the calculations by Lyytinen suggest a dozen or more meteors per hour.

slog//www.astrosurf.com/c2a)

Orbit and location of Comet P/2008 X2 (LINEAR) and the planets on 2008 December 9. Orbit diagram created by 'C2A for Windows' (http://www.astrosurf.com/c2a)

Recovery of Comet 210P/Christensen = P/2003 K2 = P/2008 X4

The return of this comet was mentioned in the “In The Sky This Month – December 2008″ posting. From that posting…

Yet another comet discovered by Eric Christensen may be visible in backyard scopes in December. This comet is a short-period comet with a period of 5.7 years. It is very faint except when close to the Sun. With perihelion predicted for 2009 January 8 at a distance of 0.53 AU from the Sun, the comet may be bright enough for backyard observers by the end of the month.

There are a lot of question marks about this comet. It was only observed for 1 month in 2003 and those observations were made after perihelion. The comet has yet to be observed during this return and its exact location is unknown. Plus since the comet has never been observed before perihelion we don’t know how bright it should be. Hopefully the comet will be picked up in the next few weeks. When/if that happens, we’ll have a better idea of how observable it will be.

Alan Watson found Comet 210P/Christensen on images taken by the STEREO-B spacecraft on 2008 December 8 and 9. At the time, he thought the comet might be new until Maik Meyer suggested the STEREO comet was actually Comet 210P/Christensen. STEREO (which stands for Solar TErrestrial RElations Observatory) is a NASA mission to study the Sun and its immediate environment. Though not designed specifically to observe comets, its cameras have the ability to pick up bright comets close to the Sun. Quite often, these comets are too close to the Sun to be seen from Earth due to the scattering of sunlight by Earth’s atmosphere.

Based on these new observations of Comet 210P/Christensen, perihelion (or closest approach to the Sun) will happen on 2008 December 19 which is 22 days earlier than predicted. For the next few weeks the comet will be too close to the Sun to be seen by anyone but STEREO and another solar spacecraft named SOHO (SOlar and Heliospheric Observatory). Luckily, these missions make their images available in near-real time allowing us to watch from our computers. From December 21-26, the comet will be visible passing very close to the Sun in images taken by the LASCO instrument on SOHO. I’ll post some pictures when the comet become visible.

In the meantime, you can look at the current SOHO LASCO C3 images here and the LASCO C2 images here. To help you get your bearings, the images are pointed at the Sun. In order to keep the Sun from blinding the camera, it is blocked by a disk (the small circle in the middle, you can also see the arm which holds the blocking disk extending from the middle of the image to the upper right edge).

p2008x4_christensen_orbit

Orbit and location of Comet P/2008 X2 (LINEAR) and the planets on 2008 December 16. Orbit diagram created by 'C2A for Windows' (http://www.astrosurf.com/c2a)


In The Sky This Month – December 2008 December 1, 2008

Posted by Carl Hergenrother in Asteroids, Comets, Meteors, planets.
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This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of December 2008. The biggest event of the month will be the Venus-Jupiter-Moon conjunction on the 1st. On the 13th, the Geminid meteor shower will peak. Though usually one of the best showers of the year, the Full Moon will ruin the show.

Planets

Venus and Jupiter start off the month in grand fashion. On the 1st, the two are located in the south-southwest just after sunset within 2 degrees of each other. Venus is by far the brighter of the pair. Not that Jupiter is a slouch only being the brightest “star” in the sky after Venus. To add to the sight, a thin crescent Moon will be located just to the upper left of the pair.

As the month progresses, Venus will rapidly move away from Jupiter. Venus will appear to start each evening higher and higher in the sky. Jupiter, on the other hand, will quickly drop towards the horizon and by the end of the month, will be located close to the southwest horizon. But Jupiter will not be alone and ends the month within 1.3 degrees of the innermost planet Mercury. The Moon can also be used at the end of the month to find the evening planets as it passes close to Jupiter and Mercury on the 29th and Venus on the 31st.

This month, Saturn starts to rise before midnight. The best time to observe it, though, is just before the start of dawn when it will be located high in the sky in the constellation of Leo. The Moon will pass close to Saturn on the nights of the 18th and 19th.

Mars is too close to the Sun to be seen.

Meteors

The month of December experiences 2 major showers, the Geminids and the Ursids, and a slew of minor ones.

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 November, twelve (12) or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Geminids (GEM)

Along with the Perseids of August, the Geminids are one of the best meteor showers delivering great displays year after year. Unfortunately, this year sees the worst circumstances possible for Geminid watching as the nearly Full Moon is located right next to the radiant. Similar circumstances occurred in October for the Orionids but observers were still able to see quite a few meteors.

According to Sirko Molau’s analysis of video data, the Geminids are already observable at the beginning of the month though their rates are very low. The peak is predicted for the nights of December 13-16. With a radiant near the star Castor in the constellation of Gemini, the Geminids are one of the rare major showers that are observable before midnight and can be observed as early as 8:00 pm though rates are usually best after 10:00 pm. Under a dark rural moon-less sky, the Geminids can produce as many as 100+ meteors per hour. With the bright Moon, rates of a few tens of meteors per hour may still be observed.

The Geminids are the result of the break-up and subsequent activity of the “asteroid” Phaethon. Why asteroid in quotes? Most meteor showers come from comets yet Phaethon is on a very non-cometary orbit and has never shown any cometary activity. There is still much scientific discussion about what exactly Phaethon is.

More details on the Geminids and their parent “asteroid” Phaethon will be posted as we get closer to its peak.

Ursids (URS)

The Ursids will produce up to 10 meteors per hour at their peak on December 22-23. That rate makes it a borderline major/minor shower though the Ursids have experienced a number of outbursts in the past. With a radiant near the “bowl” of Ursa Minor (the “Little Dipper”), this shower is also observable all night long though the best time to observe it is during the last hours of the night. More details on the Ursids and their parent comet, Comet Tuttle, will be posted later.

Minor Meteor Showers

Minor showers produce so few meteors that they are hard to notice above the background of regular meteors.

December Phoenicids (PHO)

The December Phoenicids (also just called the Phoenicids) radiate from the far southern constellation of Phoenix. Due to its southern radiant, this shower is very difficult to observe from the Northern Hemisphere. The shower results from the break-up or splitting of Comet P/1819 W1 (Blanpain) in 1819. Most years the shower only produces a few meteors per hour but on occasion up to 100 meteors per hour have been seen (1887, 1938 and 1956). No further outbursts are predicted until 2050 though that doesn’t mean we can’t be surprised. The shower is predicted to peak on December 6. In 2003, the barely active nucleus of Comet Blanpain was re-discovered by the Catalina Sky Survey.

Puppid/Velids (PUP)

These showers are another two for the southern hemisphere. There is evidence that the Puppids and the Velids are part of a much larger complex of showers that span from November through February. Their orbits suggest they are the result of the break-up of a yet-to-be-discovered comet or asteroid on a high inclination orbit (50-70 degrees). At their best, Puppid/Velids produce 5-10 meteors per hour for those south of the equator. Not too many are visible for northern hemisphere observers.

Monocerotids (MON)

The December Monocerotids (sometimes just called the Monocerotids) are produced by Comet C/1917 F1 (Mellish). Discovered in 1917 this bright comet is on a ~145 year orbit and isn’t due back till around 2062. There is evidence that this shower may have produced a number of bright fireballs during the 11th through 16th century. The shower is predicted to peak on December 7th-9th with a paltry 2 meteors per hour radiating from the faint constellation of Monoceros (located just east of Orion).

σ-Hydrids (HYD)

With a peak on December 9th of only 3 meteors per hour, these meteor from the “head” of the constellation of Hydra will be difficult to observe by all but the most advanced observers. Not much is known about this shower other than it was created by an unknown long-period or Halley-type comet with a perihelion of ~0.25 AU and an inclination of ~125 to 130 degrees.

Coma Berenicids (COM)

The Coma Berenicids are another minor shower with rates of ~5 meteors per hour at their peak. The shower is active from mid-December to late January as its radiant moves from southern Ursa Major through Coma Berenices and into Virgo. The shower may have been created by Comet C/1913 I (Lowe) a retrograde Halley-type comet. That is assuming Comet Lowe ever existed. There are some doubts that the comet was real since other observers were not able to observe the comet.

According to Peter Jennisken’s book “Meteor Showers and Their Parent Comets” a number of meteor outbursts seen between the years of 609 AD and 764 AD may have caused by this shower.

Additional information on these showers and other minor showers not included here can be found at the following sites: Robert Lunsford’s Meteor Activity Outlook, Wayne Hally’s and Mark Davis’s NAMN Notes, and the International Meteor Organization’s 2008 Meteor Shower Calendar.

Comets

Naked Eye Comets

There are no comets bright enough to be seen without binoculars or a telescope.

Binocular Comets

Comet C/2007 N3 (Lulin)

The brightest comet of the month is not visible for the 1st half of the month. Comet Lulin will be too close to the Sun until after mid-month when it will be visible low in the southeast (near the “head” of Scorpius) at the start of dawn. Comet Lulin was discovered by the Lulin Sky Survey in Taiwan on 2007 July 11. At the time the comet was located beyond the orbit of Jupiter.

The comet will be closest to the Sun on 2009 January 10 at 1.21 AU from the Sun. It will be closest to Earth in late-February when it will be only 0.41 AU from us. At that time the comet may be as bright as 4th magnitude making it an easy object for binoculars and small telescopes. In fact, the comet will be visible to the naked eye as a small faint fuzzball from dark sites.

In December the comet should brighten from 7th magnitude to 6th. I say “should” because the comet has not been seen since late October because it has been too close to the Sun. As a result, we don’t know how bright Lulin is right now. Baring a new discovery or unforeseen outburst, Comet Lulin may be the best comet of 2009.

A finder chart for Comet Lulin can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Small Telescope Comets

Comet C/2008 A1 (McNaught)

Comet McNaught is a long-period comet that passed closest to the Sun on Sept 29 at a distance of 1.07 AU (100 million miles or 160 million km). It was the first comet discovered in 2008 having been found by  Robert McNaught of the Siding Spring Survey back on January 10. It was McNaught’s 43rd comet discovery.

The comet is only visible from the Northern Hemisphere and during December it travels through northern Ophiuchus into southern Hercules. After getting as bright as 6th magnitude at perihelion, the comet will slowly fade from magnitude 8.8 to 10.0 during the month. This will probably be the last month to see this comet in regular sized backyard telescopes.

A finder chart for Comet McNaught can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Comet C/2006 W3 (Christensen)

This comet was discovered over 2 years ago on 2006 November 18 by Eric Christensen of the Catalina Sky Survey north of Tucson. At the time the comet was located at 8.7 AU from the Sun which is nearly the distance of Saturn. The comet continues to move closer to the Sun and Earth and is currently 3.8 AU from the Sun and 3.4 AU from the Earth.

The comet is currently around magnitude 10.2 and will slowly brighten during the month.  It will be traveling south through the constellations of Cepheus and Lacerta and is nicely positioned for evening observing. I was able to observe the comet visually with my backyard 12″ reflecting telescope a few weeks ago. Being small and condensed, the comet was fairly easy to see.

The comet will continue to brighten as it approaches perihelion at a still rather distant 3.12 AU from the Sun on 2009 July 6. At the time, the comet will be 8th magnitude and visible in many smaller backyard telescopes and even binoculars from dark sites. Christensen should remain bright enough to see in modest sized backyard telescopes for all of 2009.

A finder chart for Comet Christensen can be found at Comet Chasing.

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany) and Seiichi Yoshida’s Comet Homepage.

Comet P/2003 K2 (Christensen)

Yet another comet discovered by Eric Christensen may be visible in backyard scopes in December. This comet is a short-period comet with a period of 5.7 years. It is very faint except when close to the Sun. With perihelion predicted for 2009 January 8 at a distance of 0.53 AU from the Sun, the comet may be bright enough for backyard observers by the end of the month.

There are a lot of question marks about this comet. It was only observed for 1 month in 2003 and those observations were made after perihelion. The comet has yet to be observed during this return and its exact location is unknown. Plus since the comet has never been observed before perihelion we don’t know how bright it should be. Hopefully the comet will be picked up in the next few weeks. When/if that happens, we’ll have a better idea of how observable it will be.

Asteroids

Binocular and Small Telescope Asteroids

(1) Ceres

Ceres is the biggest asteroid in the Main Belt with a diameter of 585 miles or 975 km. It is so big that it is now considered a Dwarf Planet. Classified as a carbonaceous (carbon-rich) Cg-type asteroid, there are suggestions that it may be rich in volatile material such as water. Some even propose that an ocean exists below the surface. Ceres is one of two targets for NASA’s Dawn spacecraft which is scheduled to visit it in 2015. This month Ceres is located high in the sky right before sunrise in Leo brightening from magnitude 8.3 to 7.9.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand.

(2) Pallas

Pallas is also a carbonaceous asteroid though with a slightly bluish B-type spectrum. Due to its high inclination (tilt of its orbit with respect to Earth’s orbit) of 34 degrees it is a difficult target for future spacecraft missions. Pallas is large with dimensions of 350×334x301 miles or 582×556x501 km. This month it moves through the far southern constellations of Columba and Caelum. It peaks at magnitude 8.0 over the course of the month.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand.

(4) Vesta

Though not as large as Ceres, Vesta is more reflective making it the brightest asteroid in the Main Belt. Vesta is peculiar in that it appears to have evidence of volcanism on its surface. Similar to the Moon, Vesta may be covered with large expanses of frozen lava flows. It is classified as a V-type asteroid and is the only large asteroid with this classification. Many of the smaller V-type asteroids are chips of Vesta blasted off it by past asteroid and comet impacts. Vesta is similar in size to Pallas with dimensions of 347×336x275 miles or 578×560×458 km. Vesta will also be visited by NASA’s Dawn spacecraft which will arrive in 2010. On October 30, Vesta was at opposition (directly opposite from the Sun in the sky) and at its brightest. This month Vesta will fade from magnitude 7.0 to 7.6 as it moves through Pisces.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand.

(9) Metis

Metis was discovered in 1848 by Andrew Graham of Ireland. It is a S-type asteroid with a composition similar to stony meteorites (ordinary chondrites). With a diameter of 140×120x85 miles or 235×195×140 km, it is much smaller than Ceres, Pallas or Vesta. During the month, it will quickly fade from magnitude 9.1 to 9.8 as it travels through Aries just a few degrees northeast of Vesta.

A finder chart (needs to be flipped upside down for Northern Hemisphere observers) can be found at the Royal Astronomical Society of New Zealand.