Meteor Activity Outlook for November 14-20, 2009

The Meteor Activity Outlook is a weekly summary of expected meteor activity written by Robert Lunsford, Operations Manager of the American Meteor Society and contributor to this blog. The original unedited version of this week’s Meteor Activity Outlook can be found at the American Meteor Society’s site.

As seen from the northern hemisphere, meteor rates continue to be strong in November. While no major showers are active this month, the two Taurid radiants plus the Leonids keep the skies active. The addition of strong sporadic rates make November one of the better months to view meteor activity from north of the equator. Skies are fairly quiet as seen from the southern hemisphere this month. Activity from the three showers mentioned above may be seen from south of the equator, but the sporadic rates are much lower than those seen in the northern hemisphere.

During this period the moon reaches its new phase on Monday November 16th. On that date the moon lies close to the sun and is not visible at night. The same circumstances exist for this weekend. As the week progresses the waxing crescent moon will enter the evening sky but still set well before the active morning hours arrive. The estimated total hourly rates for evening observers this week is near five as seen from the northern hemisphere and three from the southern hemisphere. For morning observers the estimated total hourly rates should be near twenty-two from the northern hemisphere and ten as seen from the southern hemisphere. The actual rates will also depend on factors such as personal light and motion perception, local weather conditions, alertness and experience in watching meteor activity.

The radiant positions and rates listed below are exact for Saturday night/Sunday morning November 14/15. These positions do not change greatly day to day so the listed coordinates may be used during this entire period.

The following showers are expected to be active this week.

Andromedids (AND)

Sirko Molau’s studies of video radiants has revealed that activity from the famous Andromedid shower, noted for intense storms during the 19th century, may still be seen throughout November. The current position of the large radiant is 01:33 (023) +33. This position lies near the intersection of the constellations of Pisces, Triangulum, and Andromeda. The nearest bright star is second magnitude Mirach (Beta Andromedae), which lies four degrees to the northwest. Visual activity is expected to be low, but detectable. The Andromedid radiant is best placed near 2200 (10pm) local standard time (LST) when it lies on the meridian. At 19km/sec., the average Andromedid will appear as a very slow moving meteor. Sirko mentions that these meteors are “conspicuously slow and of almost constant activity” during this period.

Omicron Eridanids (OER)

Another shower verified by video means are the Omicron Eridanids (OER). This shower is active from November 13-20 with maximum activity occurring on the 14th. The radiant is currently located at 04:02 (060) -02. This position lies in eastern Eridanus, fifteen degrees northwest of zero magnitude Rigel (Beta Orionis) and eight degrees south of fourth magnitude star Nu Tauri. The radiant is best placed near 0100 LST, when it lies highest above the horizon. Current rates would be < 1 per hour. At 27km/sec., the average Omicron Eridanid is slow.

Northern Taurids (NTA)

The Northern Taurids (NTA) are active from a large radiant centered at 04:06 (061) +23, which lies in western Taurus, four degrees southeast of the famous naked eye star cluster known as the Pleiades. The radiant is best placed near 0100 LST, when it lies highest above the horizon, but activity may be seen all night long. Meteors from the Northern Taurids strike the atmosphere at 29km/sec., which would produce meteors of slow velocity. Expected rates would be ~3 per hour as seen from the northern hemisphere and ~2 per hour as seen south of the equator.

Southern Taurids (STA)

The center of the large Southern Taurid (STA) radiant lies at 04:09 (062) +15. This position lies in western Taurus, five degrees southwest of the 1st magnitude orange star Aldebaran (Alpha Tauri). The radiant is best placed near the meridian at 0200 LDT, but activity may be seen all night long. Striking the atmosphere at 29 km/sec., the average Southern Taurid meteor travels slowly through the skies. Rates should be near one per hour no matter your location.

November Orionids (NOO)

The November Orionids (NOO) were recently discovered by analyzing video data. This shower is active from November 18 through December 9. Maximum activity occurs on November 30. The radiant is currently (11/18) located at 05:32 (083) +16. This position lies on the Orion/Taurus border, six degrees north of the third magnitude star Lambda Orionis. These meteors are also best seen near 0300 LST when the radiant lies on the meridian and highest above the horizon. At 44 km/sec. the November Orionids produce mostly medium velocity meteors.

Alpha Monocerotids (AMO)

The Alpha Monocerotids (AMO) are active from November 15-25, with maximum occurring on the 21st. This shower has produced outbursts in the past but none are expected for many years to come. Rates are expected to be < 1 shower member per hour, even on the night of maximum activity. The radiant is currently located at 07:28 (112) +02. This position lies in central Canis Minor, only three degrees southwest of the zero magnitude star Procyon (Alpha Canis Minoris). These meteors are also best seen near 0500 LST when the radiant lies highest above the horizon in a dark sky. At 65 km/sec. the Alpha Monocerotids produce mostly swift meteors.

Leonids (LEO)

The Leonids (LEO) reach maximum activity on the morning of November 17th. The Leonids possess a sharp peak of short duration. These peaks in activity are caused by the Earth passing close to one of the filaments of material produced by comet 55P/Temple-Tuttle. This year the Earth passes close to the several filaments. Between 2100 and 2200 Universal Time (UT) on November 17th, the Earth is expected to pass through three filaments that were produced by 55P/Temple-Tuttle in 1466 and 1533. This timing is best for those watching from central Asia. A fairly strong traditional maximum is also expected near 0900 UT, which is well timed for North America. This corresponds to 0400 EST, 0300 CST, 0200 MST, and 0100 PST on the morning of the 17th. The radiant is currently located at 10:09 (152) +23. This position lies in western Leo, just west of the third magnitude star Zeta Leonis. Rates this weekend are expected to be ~1 per hour. At 70km/sec., the average Leonid is swift with a high percentage of trains. The radiant does not rise until the late evening hours so it is advised to wait until after midnight before beginning serious observations. The radiant is most favorably located during the last dark hour before the onset of morning twilight when it lies highest in a dark sky.

As seen from the mid-northern hemisphere (45N) one would expect to see approximately sixteen Sporadic meteors per hour during the last hour before dawn as seen from rural observing sites. Evening rates would be near four per hour. As seen from the mid-southern hemisphere (45S), morning rates would be near six per hour as seen from rural observing sites and two per hour during the evening hours. Locations between these two extremes would see activity between the listed figures.

The table below presents a condensed version of the expected activity this week. Rates and positions are exact for Saturday night/Sunday morning but may be used all week long.

Shower Name               RA   DEC Vel    Rates
                                   km/s  NH   SH
AND Andromedids         01h33m +33  19   <1   <1
OER Omicron Eridanids   04h02m -02  27   <1   <1
NTA Northern Taurids    04h06m +23  29    3    2
STA Southern Taurids    04h09m +15  29    1    1
NOO November Orionids   05h32m +16  44   <1   <1
AMO Alpha Monocerotids  07h28m +02  65   <1   <1
LEO Leonids             10h09m +23  70    1    1

RA - Right Ascension
DEC - Declination
Vel - Velocity relative to Earth (in km per sec)
Rates - Rate of visible meteors per hour from a
        dark site
NH - Northern Hemisphere
SH - Southern Hemisphere

November 7 – California Fireball

A brilliant fireball was seen over California during the early evening of November 7 at around 5:10 pm. Quite a few reports have been posted in the comments sections on this blog.

A comment posting by Rich gives a rather detailed observation of the event:

“11/07/2009 at approximately 1700hrs we were driving south form Santa Rosa on Hwy 12 and were passing through Sonoma when we noticed a large brilliant white fireball in a SSW direction. It first caught our attention at about 20 to 25deg off the horizon. Our visual on it only lasted only about 3-4 seconds then just before passing the hills in the distance it seemed to go out. There was no associated noise or sign of impact. It was just gone. There was a smoke or debris trail that we could see after the object was gone that was visible for perhaps a minute or so then it was dispersed by the wind.”

Pictures of the residual smoke trail can be seen on the Spaceweather.com site.

Additional news stories were published by the Daily Democrat, San Francisco Chronicle, Contra Costa Times, and others.

The fireball was most likely caused by a small asteroid, probably no larger than a basketball. Though it is possible it may have been related to the Taurid meteor shower which is near its maximum in activity, it could easily be unrelated to any shower. The very bright slow fireballs are usually asteroidal in origin while meteor showers are usually produced by comets.

Oct 28/29 to Nov 2/3 Meteors

This is a big catch-up post. The fall months usually see the highest meteor rates of the year and this year is no exception. Even though the Orionids are 2 weeks past their peak they are still producing more meteors per hour than any other currently active shower. This should change this week as the Orionids move towards inactivity. The 2 branches of the Taurid stream are nearing their maximum and will produce a consistent, though minor, contribution to November’s meteor rates. Surprisingly, the Beta Cancrids are still doing well which isn’t bad for a minor shower that we know little about. The nearly Full Moon has become a problem and will suppress meteor rates for the rest of the week.

Bob’s notes for the night of Oct 28/29 : “There was a thin veil of cirrus throughout the night that reduced the number of meteors recorded. The waxing gibbous further brightened the sky while it was above the horizon. Nothing notable in the shower numbers seen last night.”

Oct 29/30 : “The thin high clouds continued all night long again. Rates were similar to the previous night.”

Oct 30/31 : “The thin high clouds finally moved out of the area leaving pristine skies. A bright gibbous moon had less effect under the transparent conditions.”

Oct 31/Nov 1 and Nov 1/2 : “Clear skies and a bright moon were present both nights. Nothing notable was observed except for a few bright meteors.”

Nov 2/3 : “There were occasional high clouds last night which seemed to have affected the meteor rates more than the full moon.”

Obs Date (UT)  TotTime TOT SPO NTA STA ORI BCN ETT
TUS 2009-11-03 09h 10m  21  10  2   0   3   4   2
SDG 2009-11-03 11h 13m  27  17  1   4   3   2   0
TUS 2009-11-02 11h 28m  19  13  2   0   3   1   0
SDG 2009-11-02 08h 03m  52  38  2   3   8   1   0
TUS 2009-11-01 11h 26m  46  23  4   4   8   6   1
SDG 2009-11-01 11h 12m  60  35  3   6   12  2   2
TUS 2009-10-31 11h 24m  46  20  5   4   14  3   0
SDG 2009-10-31 11h 12m  61  35  5   4   14  2   1
TUS 2009-10-30 11h 23m  37  14  4   1   11  6   0
SDG 2009-10-30 10h 41m  44  21  4   4   13  1   1
TUS 2009-10-29 11h 20m  37  17  2   1   23  0   0
SDG 2009-10-29 11h 15m  48  27  4   3   11  2   1

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)
NTA/STA – Northern and Southern Taurids (includes Antihelions)
ORI – Orionids
OUI – October Ursae Minorids
BCN – Beta Cancrids
ETT – Eta Taurids

Sept 20th Fireball Over the NE

The Northeast US was treated to a doubleheader of rare sky phenomenon this past weekend. On Saturday evening, a NASA rocket launched from Virginia created a spectacular but short-lived “comet”. Later on that night around 12:30 to 1:00 am, a brilliant fireball was observed along the eastern seaboard from New Jersey to Maine. There were even sightings as far inland as the Buffalo area and far eastern Ontario.

The above map plots sightings of the fireball reported to the American Meteor Society’s Fireball page and this blog. The reports are consistent with an object that was at least as bright as the Full Moon and lasted for 3-10 seconds. There were 2 reports of delayed sonic booms, possibly caused by falling meteorites. These reports were relatively close to each in Derry, NH and Westford, MA. The fireball was most likely caused by a small asteroid (maybe a foot or so across) burning up in the Earth’s atmosphere.

Please send any additional reports to the American Meteor Society’s Fireball page.

Update on the Vancouver/Seattle Fireball

There have been more reports of Saturday night’s brilliant fireball seen over British Columbia, Washington and Oregon. The reports were submitted to the American Meteor Society’s Fireball page and to this blog. The fireball was seen as far south as SW Oregon and as far north as southern BC. All observers reported that the fireball moved in roughly an East to West direction and everyone last sighted the fireball to their West.

The map below shows where the fireball was seen. I have labeled those reports that gave a sighting to the north (N) or south (S) of their position.

Zooming in on the Vancouver/Seattle area shows that the boundary between sightings to the North and to the South is near the US/Canada border. This is a good indication that the fireball flew over the border. Interestingly, there is a report of a delayed sonic boom in the Sproat Lake area on Vancouver Island (denoted with a yellow star in the zoomed map).

Sept 15/16 Meteors

Last was another great night of meteors. It was the darkest night I’ve yet measured at my home (over the past 2+ years) so that might be helping increase the number of meteors. Then again Bob also saw increased activity with his cameras (see his notes below).

From Bobs’s notes:  “Skies finally cleared over the San Diego area. The moon is now only a thin crescent so that helped too. Rates were impressive this morning although only 6 of the 49 seen were associated with any known meteor shower.”

Obs Date (UT)   TotTime  TOT SPO ANT SPE
TUS 2009-09-16  10h 01m   39  32  4   3
SDG 2009-09-16  09h 54m   49  43  1   5

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
SPE – September Perseids

Fireball Over British Columbia and the American Northwest

Reports have been coming in of a slow bright fireball seen over the Canadian province of British Columbia and the states of Washington and Oregon. Most reports put the time of the fireball at ~8 pm local time on the evening of September 12. The fireball traveled from east to west.

Thanks to everyone who has submitted reports to this blog. Please also submit reports to the American Meteor Society’s Fireball page.They are the official archive of fireball sightings and all reports will be made available to the scientific community.

The east to west motion can rule out the re-entry of man-made space junk since 99.9+% of man-made stuff orbits the Earth from west to east. The slow motion (described as much slower than a typical meteor) and the long duration of the fireball suggest that this was due to a very small asteroid (probably no bigger than a basketball) rather than a small piece of cometary dust like most meteors.

It is possible the fireball dropped some meteorites though the lack of any reports of sonic booms suggests that material didn’t survive to reach the lower atmosphere. As close as the fireball may have seen it was much higher than an airplane. If it was similar to most slow bright fireballs, it first became visible at an altitude of 70-100 km and faded out between 20-40 km up.

The some local news stories on the fireball can be found at The Province, CBCNews, Time Colonist, and the Vancouver Sun.

The map below shows the location of sightings reported to this blog. [Map was last updated on Sept 15 at 9:30 am PST]

In the Sky This Month – August 2009

This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of August 2009. The big attraction this month is brilliant Jupiter, visible in the southeast sky during the evening, and the Perseid meteor shower.

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

Mercury - Mercury is in the midst of a poor evening apparition for northern hemisphere observers. In contrast, southern hemisphere observers will see a great display. Mercury will appear as bright as some of the brightest stars low in the western sky during evening twilight. Only folks with clear views of the horizon have a chance at seeing it. Don’t worry if you can’t, this is Mercury’s worst apparition for northerners and there will be better opportunities.

Aug 2 – Mercury and 1st magnitude star Regulus are within 0.6° of each other
Aug 17 - Mercury and Saturn within 3° of each other
Aug 22 – Moon passes 3° from Mercury

Saturn – This is the last month to see Saturn in the evening sky this year and the last chance to see it at all until November when it will be a morning object. Saturn is located low in the Western sky during twilight. At magnitude +1.1, it is not much brighter than some of the brightest stars in that part of the sky.

For those of you with access to telescopes, you will see that its rings are barely open and almost edge-on. This is the narrowest the rings will appear from Earth for the next 15 years. Though the rings are over 70,000 kilometers (43,500 miles) wide, they are only 10 meters (33 feet) thick. Since the rings are seen edge, or width, on during ring plane crossings, they can actually appear to disappear in most telescopes. The last time this happened was in 1995. This year the crossing happens on Sept 4 when Saturn is too close to the Sun to be observed. Still, the rings will appear very narrow and line-like this month.

Aug 17 – Saturn and Mercury within 3° of each other
Aug 22 – Thin crescent Moon within 6° of Saturn

Jupiter and Neptune -Jupiter is the planet highlight of the month. Based on the comments left on this blog, many people have been noticing Jupiter in the southeast sky during the evening. At magnitude -2.8, Jupiter is ~13 times brighter than the brightest stars in the sky this month. Of all the planets, only Venus, and on very rare occasions Mars, are brighter.

Jupiter rises during evening twilight and is highest in the sky aaround midnight. Due to Jupiter’s location in the southern constellation of Capricornus , it never gets very high this year.

For those with a telescope or binoculars and a dark sky, Neptune is located within 1/2 to 3/4 degrees of Jupiter. Jupiter will be a bright magnitude -2.8 while Neptune will be a faint +7.8. That makes Jupiter over ~17,000 times brighter than Neptune. Even Jupiter’s 4 large Galilean moons are about a dozen times brighter than Neptune even though they are much smaller. The big reason for the faintness of Neptune is its distance from both the Earth and Sun. It is roughly 6 times further away from us and the Sun as Jupiter. The distance also explains its apparent small size of 2.3″. A good sized telescope will be required to see Neptune as anything other than a faint star.

Image of Jupiter by Bob Lunsford from early May 2009. Note one of its moons near the left edge.

Though Neptune wasn’t discovered until 1846, it was actually observed by Galileo on two occasions in 1612 and 1613. Similar to this month’s circumstances, Jupiter was passing very close to Neptune. Galileo observed and recorded Neptune as a star in the vicinity of Jupiter. There is also evidence that he noticed that Neptune had moved but didn’t follow up on it. So when you observe these 2 planets imagine what Galileo must have been thinking nearly 400 years ago.

Aug 6 – Full Moon passes within 3° of Jupiter and Neptune
Aug 14 – Jupiter at opposition (meaning Jupiter is closest to Earth, at its brightest for the year and visible all night long)
Aug 17 – Neptune at opposition

Uranus – Uranus is located in western Pisces. It is bright enough to be seen in small binoculars at magnitude +5.8 but will still require a telescope in order to see it as anything other than a star (it’s disk is only 3.5″ across).

Aug 9 – Moon within 5° of Uranus

Mars – Many of you may have received an email or read stories about how Mars is going to be big and bright this month. Some stories suggest that it will rival the Full Moon in size. Well, it’s all bull. This story has been circulating around the internet every year since August of 2003 when Mars did have a closer than usual (but not unusual) approach to Earth. For some reason the email story gets re-circulated every year with only the year changed. Also note that the email was never factual. Even in August of 2003, Mars never got as bright as the Moon. It did get as bright as it ever gets which is a little brighter than Jupiter appears this month.

Mars can be seen in the eastern sky a few hours before sunrise. It rises between 1 and 1:30 am all month long though it won’t get high enough to clear most trees and building till about 3 am. At magnitude +1.1, its brightness matches those of many of the bright stars in the 2 constellations it is moving through this month, Taurus and Gemini.

Aug 16 – Moon within 3° of Mars

Venus - Venus continues to slowly climb higher every night. It is currently a morning object and is best seen an hour before sunrise low in the eastern sky. For Southern Hemisphere observers, it has already peaked for this apparition and is slowly dropping back towards the horizon. For Northern observers, Venus will continue to climb higher until early August. It rises between 3am and 4am for most observers though it will be low in the eastern sky the while time. For binocular and telescope users, Venus is now in a gibbous phase (between half and full) and is slowly shrinking as it moves further away from Earth.

Aug 17 – Moon within 2° of Venus

Meteors

August is one of the best months for meteor activity. The year is usually split in 2 with January through June having low rates with few major showers while July through December (really through the 1st week of January) have high rates with many major showers.

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 August, 12 or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Perseids (PER) [Date range = July 17 - Aug 24, Max = Aug 12]

The Perseids are one of the best meteor showers of the year and rarely disappoint. This year’s display will bring a mixed bag. On one hand, the Moon will be nearly full and poorly placed. The Moon’s bright light will drown out many of the fainter Perseids bringing the number of visible meteors down significantly. On the other hand, there are predictions that this years’s display will be richer than usual. Meteor stream models predict increased rates around 0800 and 0900 UT on the morning of August 12 (4:00-5:00 EDT, 1:00-2:00 am PDT). The reason is a ribbon, or filament, of dust produced by the Perseid parent Comet Swift-Tuttle in 1610. Some predictions are calling for a ZHR rates of 200 which is twice as good as the usual rates of 60-120. Of course, those rates are only valid for a very dark sky with no Moon. Still rates of 30 per hour may be possible for many non-urban locations.

Minor Meteor Showers

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

Southern δ-Aquarids (SDA) [Date range = July 12 - Aug 19, Max = July 28]

The Southern δ-Aquarid shower peaked in late July. There should still be significant activity from this shower in early August. By the middle of the month, all activity should be over. They are part of the Machholz complex of asteroids, comets and meteor showers that are the result of the breakup of a single comet into hundreds of smaller objects over the past thousands of years. The complex includes comet 96P/Machholz, the suspected extinct comet 2003 EH1, hundreds of Marsden and Kracht group comets, and the Quadrantid and Arietid meteor showers.

It is the comets of the Marsden group that are directly resposible for the SDA shower. These small comets have never been observed from Earth. There are only seen by spacecraft that can observe very close to the Sun. Due to the very small perihelion distance of these comets (~0.05 AU) they only get bright enough to be discovered when close to the Sun. Currently there are ~33 comets that are known to be members of the Marsden group.

The shower radiates from RA = 22h 36m, Dec = -16 deg.

Piscis Austrinids (PAU) [Date range = July 15 - Aug 10, Max = July 27]

This shower of unknown parentage is a difficult one for northern observers due to the southern location of its radiant (RA = 22h 44m, Dec = -30deg). Similar to the SDAs and the CAPs below, it is active from mid-July to mid-August with a maximum around July 27. At maximum one can expect 2-4 meteors per hour from a dark site. Rates will be even lower for northern observers.

α-Capricornids (CAP) [Date range = July 3 - Aug 15, Max = July 29]

The CAP is yet another southern shower (RA = 20h 28m, Dec = -10 deg) that is difficult to observe from northern latitudes. With a peak on July 29, it can be expected to produce 3-6 meteors per hour. Unlike the PAUs, the CAPs appear to be associated with a known comet, 169P/NEAT.

Comets

Naked Eye Comets (V < 6.0)

None

Binocular Comets (V = 6.0 – 8.0)

None

Small Telescope Comets (V = 8.0 – 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 8.2 and should be at its brightest this month.  It is moving southeast while paralleling the summer Milky Way. This month the comet will travel through the constellations of Vulpecula, Sagitta and Aquilia. The comet is best seen after 10 pm.

The comet reached perihelion at a rather distant 3.12 AU from the Sun on 2009 July 6. Becuase of its large perihelion distance, the comet will only slowly move away from the Sun and though it will slowly fade from here on out it should remain bright enough to be seen in modest sized backyard telescopes for all of 2009.

A finder chart for Comet Christensen can be found at Comet Chasing and Aktuelle Kometen (in German).

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/2008 Q3 (Garradd)

This is the surprise comet of the summer. From time to time what appears to be a faint run-of-the-mill comet will undergo an outburst and brighten substantially. This is the case with Comet Garradd which was discovered by Gordon Garradd of the Siding Spring Survey (Australia). He used the 0.5-m Uppsala schmidt telescope to discover this comet back on 2008 August 27.

The comet was a faint 19th magnitude at discovery. With perihelion expected on 2009 June 23 at 1.80 AU from the Sun, it was expected to brighten but only to about 12th-14th magnitude. Two weeks ago the comet was sitting at 15th magnitude. Bright enough for CCD imaging but too faint for nearly all visual observers. On April 20th Micheal Jager imaged the comet and found it too be much brighter. Over the next few days, visual observers were able to confirm the outburst and estimated the comet to be as bright as magnitude 8.9.

With perihelion in June, the comet is in full retreat from the Earth and Sun and has faded to 9th magnitude. The comet is slowly moving through western Virgo low in the western sky after evening twilight. This will be the last month to see the comet as it sinks into the twilight sky.

A finder chart for Comet Garradd 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/2008 T2 (Cardinal)

Rob Cardinal, an astronomer at the University of Calgary in Canada, discovered this comet last October. The comet was discovered as part of a survey at  the Rothney Astrophysical Observatory for new Near-Earth asteroids at high declinations. In fact the comet was found within 10 degrees of the North celestial pole. At the time of discovery, the comet was ~14th magnitude.

At perihelion on June 13th, the comet passed within 1.20 AU of the Sun. The comet can only be seen from the Southern Hemisphere as it is located south of the Sun. The comet is currently magnitude 9.0 to 10.0 as it moves southeast from Antilia to Vela and Centaurus in the evening sky. It is too bad the comet is located so far from Earth. At a distance of 1.8 AU from Earth, it is located on the other side of the Sun. If this comet has approached as close as Comet Lulin (0.4 AU) did, Comet Cardinal would be shining at 5th magnitude and be visible to the naked eye from dark locations.

A finder chart for Comet Cardinal 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.

22P/Kopff

All of the above comets are long-period comets which will not return to the inner Solar System for thousands to millions of years. Comet Kopff is a frequent visitor with an orbital period of 6.4 years. Discovered on 1906 August 20 by August Kopff of Germany, the comet has been observed during every subsequent return except one.

The comet reached perihelion at 1.58 AU from the Sun on May 25. Though now moving away from the Sun, the comet still moving closer to Earth and will be located 0.78 AU from us at the end of the month. Recent observations place the comet at magnitude 9.5 which is about as bright as it will get this apparition. The comet spends August in Aquarius.

A finder chart for Comet Kopff 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)

(3) Juno

Juno was the 3rd asteroid to be discovered after (1) Ceres and (2) Pallas. It was found by German astronomer Karl Harding on September 1, 1804. With dimensions of 320×267×200 km (192 x 160 x 120 miles) Juno ranks as the 10th largest asteroid in the Main Belt though it is the 2nd largest stony S-type asteroid.

This month it will be moving slowly eastward through Pisces while brightening from magnitude 9.0 to 8.2. Peak brightness will come at opposition on Sept. 22 when Juno will be as bright as magnitude 7.6. A few degrees to the eats of Juno is another bright asteroid, (18) Melpomene which is described in its own section.

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 Juno from Heavens Above.

(7) Iris

Iris is an inner Main-Belt asteroid that can occasionally get as bright as any asteroid. This year, Iris did not get as bright but still become a binocular object (albeit a difficult one) at opposition on July 4 at magnitude 8.7. During August, it is located in the constellation of Sagittarius at magnitude 9.3 at the start of the month and magnitude 9.8 at the end.

With a size of 240 x 200 x 200 km, Iris is the 5th largest stoney S-type asteroid. It was discovered in 1847 by John Russel Hind, the 1st of 10 asteroids he discovered.

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 Iris from Heavens Above.

(18) Melpomene

Just a few degrees to the east of (3) Juno lies another nice asteroid target for small telescopes. (18) Melpomene is also located in the constellation of Pisces and is only a little bit fainter than Juno, brightening from magnitude  9.4 to 8.7 in August.

Melpomene is another stoney S-type asteroid and similar to Iris was also discovered by John Russel Hind. Found in 1852, it is his 5th of 10 asteroid discoveries.

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 Iris from Heavens Above.

July 22/23 Meteor

Both the Tucson and San Diego cameras had to deal with clouds last night. According to Bob: “Fog rolled in near 2am prematurely ending this session. There was also some altocumulus clouds earlier in the evening that may have also affected the rates.” Here in Tucson I was very surprised to even get a single meteor. Now if the sky would just clear for a night or two next week, we should have some nice results as the Southern Delta Aquariids, as well as the Alpha Capricornids and Piscids Australids, peak.

Obs  Date (UT)   TotTime TOT SPO ANT CAP SDA PAU PER
TUS  2009-07-23  00h 30m  1   1   0   0   0   0   0
SDG  2009-07-23  05h 00m  12  6   0   3   2   0   1

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
CAP – Alpha Capricornids
SDA – Southern Delta Aquariids
PAU – Piscids Australids
PER – Perseids

Mason-Dixon Fireball – July 6

There have been reports of a fireball accompanied by sonic booms over PA and MD. The fireball was observed shortly after 1 am on the morning of Monday, July 6. Based on reports sent to this blog, the American Meteor Society and local news outlets, the fireball was seen from OH to CT including reports from PA, MD, NY and NJ.

The map below shows the location of sightings (yellow stars) and sonic booms (red circles). It is obvious that the sonic boom reports are clustered in the area of York and Lancaster, Pennsylvania.

What was it? Most likely the fireball was the result of a small asteroid (no bigger than a basketball) hitting Earth’s atmosphere at ~10 miles per second. The reports all confirm the telltale signs of a small asteroid ablating and breaking up in the atmosphere (blue green glow, long tail, multiple fragments, delayed sonic booms). There is a good chance that this fireball dropped a number of meteorites and I’m sure meteorite hunters are already in the area.

Additional information can be found at WGAL 8 and The Baltimore Sun.

Also remember to submit reports of this fireball to the American Meteor Society. These reports are a great help for understanding these objects and in the recovery of meteorites.