In The Sky This Month – February 2009
January 31, 2009 82 Comments
This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of February 2009. This month finds Venus at its best in 8 years. Also Comet Lulin should continue to brighten and perhaps approach naked eye brightness.
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.
Venus the highlight of the month of February. 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. Venus is at maximum height at the beginning of the month. As the month progresses, it will appear slightly lower in the sky. On February 20, it will be at its brightest (mag -4.6). Through a telescope, Venus appears like a brilliant less than half moon. The Moon will pass within 1.2 degrees of Venus on the night of the 29th.
Saturn continues to rise earlier and brighten as it approaches its March 8 opposition. Opposition is when a planet (or comet or asteroid) is located opposite the direction of the Sun. On this date, Saturn will be closest to Earth and at its brightest. It rises between 8 and 9pm at the start of the month. By the end of the month, Saturn will rise just after the end of evening twilight. All month long, it is highest in the sky around midnight.
Jupiter, Mars and Mercury are all located near each other low in the early morning sky. From the Northern Hemisphere, everything happens very close to the horizon so any obstructions (trees, buildings, etc.) could hid the action. The view is much better from the Southern Hemisphere.
Mercury is the only one of the three that is visible at the start of the month. It is highest on Feb 6-7. As it starts to sink back towards the horizon, Mars and Jupiter rise to meet it. On Feb 24 all three planets are located within 4 degrees of each other. The trio may be easier to find a few days earlier (Feb 22/23) when the crescent moon will be nearby.
The month of January experiences no major showers and only a few minor ones.
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
Minor Meteor Showers
Minor showers produce so few meteors that they are hard to notice above the background of regular meteors.
Alpha Centaurids (ACE)
This minor shower is best seen from the Southern Hemisphere and in fact is not above the southern horizon for most of North America and Europe. The Alpha Centaurids appear to radiate from a point near the star Alpha Centauri, hence the name Alpha Centaurids. If that star sounds familiar, it is the nearest stellar (star) system to the Sun. The meteors don’t actually come from Alpha Centauri, they come from an unknown comet. The shower is part of a complex of southern showers that are active from November through March. The Puppid/Velids of December are also part of this complex.
The shower is visible from January 28 to February 21 with a peak on February 7. For Southern Hemisphere observers, rates usually reach 5-7 per hour. Short hour-long outbursts have been reported in the past.
Delta Leonids (DLE)
The Delta Leonids are another minor shower with a period of activity from February 15 to March 10. Near its February 25 peak, rates may reach a paltry 2 per hour.
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.
Naked Eye Comets (V < 6.0)
Comet Lulin may become brighter than magnitude 6 this month. More on this comet can be found in the next section.
Binocular Comets (V < 8.0)
Comet C/2007 N3 (Lulin)
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.
The comet is currently around magnitude 6.8 which makes it an easy object for binoculars and small telescopes from a dark sky. Unfortunately this comet is not brightening as rapidly as expected. Rather than reaching 4th magnitude at the end of the month, 5th magnitude may be more likely. Still this makes the comet a very nice object in binoculars and small telescopes. It may even be seen with the naked eye from very dark locations.
The comet starts the month low in the southeast before dawn in the middle of Libra. Due to its retrograde orbit, the comet is moving in almost the exact opposite direction as the Earth. As a result, it is rapidly moving to the west every night. Over the course of the month, Lulin will cross half of Libra, all of Virgo and most of Leo. On the 16th, it will be located a few degrees north of Spica, the brightest star in Virgo. On the 23rd, it will be a few degrees south of Saturn and on the 28th it will be within a few degrees of Regulus, the brightest star in Leo.
A finder chart for Comet Lulin can be found at Comet Chasing.
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 9.7 and will slowly brighten during the month. It will be traveling south through the constellation of Lacerta and is nicely positioned for early 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.
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.
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. The comet starts the month within the large Hyades open star cluster in Taurus. It will slowly move to the east during the month.
A finder chart for Comet Kushida can be found at Comet Chasing.
Binocular and Small Telescope Asteroids (V < 10.0)
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 7.2 to 6.9. It reaches its brightest at opposition on February 25.
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 through the far southern constellations of Eridanus and Lepus. It fades from magnitude 8.2 to 8.4 over the course of the month.
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 is an evening object moving just north of the “head” of Cetus. It will fade from magnitude 8.1 to 8.3.
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 58 miles (96 km) it is 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 is located in Cancer. It starts the month at magnitude 8.9 and is at its brightest at opposition on February 4 at magnitude 8.8. By the end of the month, it will have faded to 9.6.
Discovered in 1854, Amphitrite was the 29th asteroid to be discovered. Similar to Euterpe, Amphitrite is also a stoney S-type asteroid. With an average diameter of 127 miles (212 km) it is bigger than Euterpe though its further distance from the Earth and Sun keeps it from getting as bright.
Ampitrite is located in Leo all month and will brighten from magnitude 10.2 to 9.7. It will reach its brightest at opposition on March 22 at magnitude 9.1.