In The Sky This Month – November 2008

This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of November 2008.

Planets

Venus is the very bright “star” close to the southwestern horizon for an hour or so after sunset. When it is above the horizon, it is the brightest “star” in the sky. Every night Venus will appear to be a little bit higher in the sky. As the month progresses Venus will also appear a little further to the south. Venus starts the month in the constellation of Ophiuchus. It crosses into Sagittarius by the 2nd week of the month. By the end of the month, Venus will be located very close to Jupiter (within 2 degrees).

Jupiter is located in the constellation of Sagittarius. At the beginning of the month, Jupiter starts the night low in the southwestern sky and sets around 9 pm. As the month progresses, it will appear lower in the sky and further to the west. Jupiter is fainter than Venus but brighter than any star. As mentioned in the Venus section above, Jupiter will close in on Venus all month. By the end of the month, Jupiter and Venus will be located within 2 degrees of each other.

Saturn is located high in the east just before sunrise in the constellation Leo. It is as bright as many of the brightest stars.

Mercury is located low in the east-south-east right before sunrise. By the 2nd week of the month it is too close to the Sun to be seen. Mercury won’t be observable again until mid-December.

Mars is too close to the Sun to be seen.

Meteors

November sees a number of meteor showers including the Leonids which have produced spectacular storms in the past.

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, sixteen (16) or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Leonids (LEO)

The Leonids have produced some of the most spectacular meteor displays in history. Rates as high as ~70,000 meteors per hour (that’s ~20 meteors per second) were seen in 1833 and 1966. Every ~33 years, the parent comet of the Leonids, Comet Tempel-Tuttle, returns to the vicinity of the Earth. For a few years after Tempel-Tuttle’s last perihelion in 1998, the Leonids produced enhanced rates of meteors as high as 100s to 1000s of meteors per hour.

What will 2008 bring? Well first off, this is a bad year with regards to the Moon. Similar to October’s Orionids, the Moon will be bright and close to the Leonid radiant during their peak limiting the number of fainter meteors that can be seen. In a normal year, the Leonids produce maximum rates of ~10-15 meteors per hour. The Moon will cut those rates in half or more.

There are 2 predictions for enhanced activity this year. The International Meteor Organization summarizes this year’s prediction with the following taken from their 2008 Meteor Calendar:

The Leonids may produce just a normal maximum close to their ‘traditional’ nodal time in 2008, on November 17, around 09h UT, though the bright waning Moon will be a severe problem if so. However, Mikhail Maslov proposed that the shower may show a peak with ZHRs ~ 130 at 00h22m UT on November 17 in WGN 35:1 (2006, p. 7), with meteors brighter than average. Many of his other model calculations for the Leonids in the period 2001 — 2006 showed some differences to what was actually observed, so while this this is an interesting possibility for 2008, its accuracy is unknown and unproven. Jérémie Vaubaillon finds instead two potential stream encounters, centred on November 17 at 01h32m UT (1466 trail; ZHR most uncertain — perhaps ~ 50, but maybe ~ 25 — 100) and November 18 at 21h38m UT (1932 trail; ZHR possibly ~ 20 at best?). Checking on all these times (or any others that may be suggested subsequently) will be difficult due to the Moon, but valuable.

What does this mean? Most of us, especially in the United States, will only see the “normal” maximum on the morning of November 17 with low rates due to the bright Moon. For those located throughout Eurasia, one, two or three of the possible outbursts may be observable. The Leonids are best observed in the hours before sunrise. They will appear to radiate from the western part of the constellation of Leo.

Minor Meteor Showers

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

Orionids (ORI)

When you see an Orionid meteor, you are seeing small pieces of Halley’s Comet which were released thousands of years ago. The Orionids were the best shower during the month of October. At their peak, Orionids appear to radiate from a point in the constellation of Orion, hence the name Orionids. Meteor shower radiants are not stationary and on average move about a degree per day towards the east. As a result, in November the Orionids actually appear to radiate from the southwestern Gemini. Though they peaked around Oct 21, a few Orionids will be observable after midnight till the middle of November.

Northern and Southern Taurids (NTA/STA)

The Taurids never produce more than ~5 meteors per hour. They make up for their low rates by being active for over two months and by producing many bright fireballs. Their fireballs are more apparent to the average observer because, unlike most meteor showers, the Taurids are observable all night long rather than just in the morning. There is a chance that the Taurids will produce a higher number of fireballs this year than usual. There is a good chance that most fireballs being reported this month will be Taurids. They are active for the entire month of November with the northern branch (NTA) peaking around November 14. Though named after the constellation of Taurus, theTaurids radiate from a point between the constellations of Taurus and Aries this month.

The Taurids are produced by Comet 2P/Encke. Encke is an enigmatic object with the shortest period for any known comet at 3.3 years. First observed in 1786, it has been observed over ~60 orbits and has been seen every year since 1993.

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/2008 A1 (McNaught)

Comet McNaught is a long-period comet that will 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 Jan 10. It was McNaught’s 43rd comet discovery.

The comet is only visible from the Northern Hmisphere and during November it crosses the constellation of Ophiuchus. The comet will slowly fade from magnitude 7.5 to 8.5 during the month. I was able to observe this comet with my 12″ Dobsonian from my backyard in Tucson. The comet was not an easy object to see even in a large telescope from a site with moderate light pollution. Dark skies will definitely help with this one. From dark skies, it can be seen in binoculars or a small telescope. From brighter skies, a telescope is required.

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

Small Telescope Comets

Comet 6P/d’Arrest

Comet 6P/d’Arrest was one of the first short-period comets to be observed. First seen by the Frenchman Philippe de la Hire in 1678, the comet was definitively discovered by Heinrich Louis d’Arrest of Germany on 1851 June 28.

Comet d’Arrest is in a short-period orbit with a period of 6.5 years. It passed closest to the Sun back on Aug 14 at a distance of 1.35 AU (125 million miles or 200 million km). The comet is a very difficult object for observers in the Northern Hemisphere because it is located in the southern constellation of Sculptor. Even though it will slowly move north this month, observing conditions will not improve because the comet will also fade from magnitude ~9.5 to ~11.0 by month’s end. This comet will definitely require a telescope and dark skies to be seen.

A finder chart for Comet d’Arrest 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.

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 low in the eastern sky right before sunrise in Leo brightening from magnitude 8.6 to 8.4.

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 350x334x301 miles or 582x556x501 km. This month it moves from the southern constellation of Lepus into the even further southern constellation of Columba. It brightens from magnitude 8.2 to 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 347x336x275 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 6.5 to 7.0 as it moves through 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.

(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 140x120x85 miles or 235×195×140 km, it is much smaller than Ceres, Pallas or Vesta. Metis will be at opposition and also at its brightest (magnitude 8.5) on November 4. Opposition is also the moment when Metis will be closest to Earth this year at a distance of 1.14 AU. During the rest of the month, it will slowly fade to magnitude 9.1 as it travels through Aries just a few degrees south 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.

About Carl Hergenrother
I am a professional astronomer specializing in the study of comets, asteroids and meteors. This blog will focus on my professional and amateur work in this field

4 Responses to In The Sky This Month – November 2008

  1. Heather Cole-Kelleher says:

    Can anyone help? I need some information on the Taubin Comet. I think that is the name. It was seen on November 4, 2008.

  2. Carl Hergenrother says:

    Hi Heather,

    There isn’t any comet by the name of Taubin. Do you have any other info on it? Perhaps the name is wrong and it is one of the other comets that are currently visible.

    You mentioned it was seen on Nov 4. If it was only seen on one night then perhaps you are referring to a meteor or fireball.

    – Carl

  3. Heather Cole-Kelleher says:

    Thanks

  4. mikia wright says:

    i love this website

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