In The Sky This Month – February 2009

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.

Planets

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.

Meteors

The month of January experiences no major showers 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

None.

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.

Comets

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.

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 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.

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. 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.

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 (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 7.2 to 6.9. It reaches its brightest at opposition on February 25.

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 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.

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 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.

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 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.

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.

(29) Amphitrite

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.

Jan 27/28/29/30/31 Meteors and the Alpha Centaurids

Rates have been fairly constant over the past week. For the SALSA camera in Tucson, about 15 meteors, give or take a few, are being detected each night. Bob’s camera in Tucson is more sensitive and can detect fainter meteors. His camera is picking up ~30 meteors per night.

The Alpha Centaurids (ACE) are now active. This minor shower is best seen from the Southern Hemisphere and in fact is barely above the southern horizon from Tucson and San Diego. For observers north of ~+32N, the radiant never rises above the horizon. It is interesting that both cameras have been detecting 1-2 ACEs nearly every night. This suggests that the shower is more active than usual. So far there have been no reports of elevated activity from observers down south. It is also possible that the meteors being reported as ACEs are just Sporadics that happen to line up with the ACE radiant. The rather large number of ACEs detected in such a short period of time (the ACE radiant is only above the horizon for an hour or so per night) makes me wonder if the Alpha Centaurids are more active than usual.

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.

Obs  Date (UT)   TotTime TOT SPO ANT ACE
TUS  2009-01-31  11h 41m  14  12  1   1
SDG  2009-01-31  10h 40m  42  35  5   2
TUS  2009-01-30  11h 36m  18  15  3   0
SDG  2009-01-30  11h 18m  33  27  4   2
TUS  2009-01-29  09h 17m  15  13  2   0
SDG  2009-01-29  11h 37m  33  28  4   1
TUS  2009-01-28  11h 32m  15  14  0   1
SDG  2009-01-28  09h 53m  26  25  1   0

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions
ACE – Alpha Centaurids

Jan 25/26/27 Meteors

The mutli-day rain storm that was forecast to hit CA and AZ didn’t happen. Though the rain stayed away the past 2 nights were plagued by clouds. The Tucson camera only caught 9 meteors over the past two nights between the clouds. In San Diego, Bob was able to get one clear night in and recorded 33 meteors.

Obs  Date (UT)   TotTime TOT SPO ANT
SDG  2009-01-27  11h 38m  33  27  6

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions

Jan 24/25 Meteors

Last night was the first clear night in Tucson since the middle of last week. Even with the clear conditions, the number of meteors continues to be low. This will likely be the case for the next few months. A big reason for this is the lack of active showers. Not only are no major showers active but none of the well determined minor ones are either. There may be a few very minor ones active that are poorly characterized but even they won’t produce a noticeable amount of activity. Barring a surprise shower (which is always a possibility), rates will remain low until the Lyrids return in mid-April (peak on Apr 22).

Obs  Date (UT)   TotTime TOT SPO ANT
TUS  2009-01-25  11h 49m  12  12  0

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions

Jan 17/18/19/20/21 Meteors

It has been awhile since I posted the nightly video meteor results. Most of these results are from last weekend and earlier this week. Intermittent clouds have made it difficult to detect many meteors. Also the past 3 nights have been completely clouded out. Though it is once again clear, the clouds will soon return as the forecast for next week calls for another multi-day rain event.

This time of the year is rather boring for meteor observing. There are no major showers until April and the rate of Sporadic meteors are at their yearly low

This January seems to be making up for its low number of meteors but providing many bright fireballs. One of the meteors detected by my camera on Jan 17/18 was a nice -5 magnitude fragmenting fireball.

Obs  Date (UT)   TotTime TOT SPO ANT COM
TUS  2009-01-21  07h 25m  2   2   0   0
TUS  2009-01-20  11h 20m  13  10  2   1
SDG  2009-01-20  11h 47m  27  24  1   2
TUS  2009-01-19  06h 55m  12  12  0   0
TUS  2009-01-18  02h 00m  2   2   0   0
SDG  2009-01-18  11h 50m  27  23  2   2

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions
COM - Coma Berenicids

More on the California Fireball – Jan 18

More reports of Sunday evening’s fireball have been posted on this blog and the American Meteor Society Fireball page. Thanks to everyone who has been posting! If you would like to make an official report please visit the American Meteor Society’s Fireball Report page. The form is very simple and you don’t need to know any astronomy to make a valuable contribution.

The fireball occurred on Sunday evening, January 18, at ~5:30 pm (give or take 20 minutes). Amazingly this was only ~15 minutes after sunset for people on the coast so the sky was still very bright. The fireball must have been quite a spectacle to be seen against such a bright sky.

Based on the reports submitted so far, it was seen from 4 states (California, Nevada, Utah and Arizona). Here’s a map of the sightings reported so far.

california_fireball_jan182

Location of reports for the January 18 early evening fireball. Reports from the American Meteor Society and this blog. Map produced on Google Earth.

Most people said it was a white/blue though a few observers noted it changed into many colors. This is consistent with a meteor. The fireball ended its passage through the atmosphere with a bang, something astronomers call a “terminal burst”. This marks the final break-up, or explosion, of the small asteroid that created the fireball. Many reports also mentioned that a smoky trail was visible for several minutes after.

So what was it? Most likely it was a small asteroid or “space rock”. Probably no bigger than a basketball, it burnt up in the Earth’s atmosphere as it traveled at a speed of a few tens of miles per second. Though it may have looked like it was only a few hundred feet above the ground, it was in fact 40-60 miles up.  It is definitely possible that some small pieces survived to hit the ground.

Turns out a second very bright fireball was seen over northern California later the same night. At least 3-4 people reported a fireball in the San Francisco area at 11:26 pm. The two fireballs are probably unrelated.

So far no videos of the twilight fireball have surfaced. Because the sky was so bright, most of the all-sky meteor cameras were still off. The second fireball was captured by an all-sky meteor camera in Yuba City operated by Richard Spalding. His video can be seen here.

Another California Fireball

I have received a few reports about a bright fireball seen across California. Sightings have been sent in from San Francisco to San Diego.  There is some disagreement on the time with some people saying it occurred on January 18 around 5:40 pm PST and others saying it happened on January 19 around 4 am PST. So perhaps we are talking about 2 unrelated but spectacular fireballs, the evening one was seen over southern California while the morning one was a northern CA object.

Neither of these fireballs are related to the one seen over northern Europe a few days ago.

Based on the number of hits I’ve been getting the last 2 days and the number of people of people who found this blog by searching for info about a California fireball, this must have been seen by many folks. Please post what you saw in the comments section. Thanks.

Fireball over Nothern Europe – Jan 17

A bright fireball was reported over the northern European countries of Sweden and the Netherlands. Undoubtedly the fireball was seen from other nations as well. Images and movies posted on-line suggest this fireball was as spectacular as the ones seen over Alberta/Saskatchewan in Canada on November 20. (Past posts on the Canadian fireball can be found here, here, and here.)

The fireball occurred on the night of January 17 at 20:10 (8:10 pm) CET or 19:10 UT. A video of the fireball taken from Sweden was posted on YouTube.

Still frames from the video can be found here.

A distant image of the fireball from an all-sky fireball monitoring camera in the Netherlands can be found here. The fireball is just visible above the northeast horizon.

Jan 16/17 Meteors

A bout of clouds kept the meteor count low in Tucson last night. In San Diego, Bob reports that “Meteor rates were similar to last night. Only a few birds and planes were seen tonight in addition to the meteors, which is normal.”

Obs  Date (UT)   TotTime TOT SPO ANT COM
TUS  2009-01-17  11h 54m  10  9   0   1
SDG  2009-01-17  10h 32m  39  32  4   3

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions
COM - Coma Berenicids

Jan 14/15/16 Meteors

From Bob’s notes for Jan 14/15: “Rates were a bit stronger tonight. A slow increase should be expected as the moon wanes. This was the first near all night session in which there were no false detections, meaning that no bugs, birds, or planes passed through the field of view and triggered the detection system.”

Here in Tucson, I detected the usual 4-5 planes flying over the house. Meteor rates have been fairly strong the past 2 nights and are not much below the average levels in November and December.

Obs  Date (UT)   TotTime TOT SPO ANT COM
TUS  2009-01-16  11h 59m  19  17  2   0
SDG  2009-01-16  11h 41m  38  31  3   4
TUS  2009-01-15  10h 59m  19  16  0   3
SDG  2009-01-15  10h 31m  35  31  2   2

TUS – Camera in Tucson operated by Carl Hergenrother
SDG – Camera in San Diego operated by Bob Lunsford
TotTime – Total amount of time each camera looked for meteors
TOT – Total number of meteors detected
SPO – Sporadics (meteors not affiliated with any particular meteor shower)
ANT – Antihelions
COM - Coma Berenicids

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