Oct 7/8/9 Meteors and Watching for LCROSS

After a few days of clouds, the sky was once again clear over southern AZ. Still, rates are probably lower than they should be due to a bright Moon shining directly overhead during the prime meteor watching hours.

This week should see steadily increasing meteor rates due to the rise of the Orionids (towards an Oct 21/22 peak) and a less obtrusive Moon.

I was up this morning watching the Moon for evidence of NASA’s LCROSS impact experiment. Though the seeing was rather poor, I was able to get some good quality video. Nevertheless, I didn’t see anything from the impact. Then again this was the case with professional telescopes many times larger than mine.

Bob’s notes for 10/8:

“Much like last night, a bright moon and periodic clouds limited the number of meteors recorded tonight. It was interesting to note the Southern Taurids equaled the sporadic rate last night.”

.. for 10/9:

“More or the same with clouds and the moon…”

Obs Date (UT)  TotTime TOT SPO NTA STA ORI DAU DRA EPC
TUS 2009-10-09 10h 36m  35  19  3   1   4   2   2   0
SDG 2009-10-09 09h 56m  24  17  -   7   0   -   0   0
TUS 2009-10-08 00h 00m  Clouds all night
SDG 2009-10-08 08h 56m  18  8   -   8   2   -   0   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)
NTA – Northern Taurids (includes Antihelions)
STA – Southern Taurids (includes Antihelions)
ORI – Orionids
DAU – Delta Aurigids
DRA – October Draconids (Giacobinids)
EPC – September Epsilon Piscids

Tonight: Moon-Pleiades-Mercury Conjunction

This evening is your best chance to see the innermost planet Mercury. Since Mercury is located ~2/3rds of the way closer to the Sun than the Earth, it never travels very far from the Sun in our sky.

The Moon will also located just above Mercury this evening, April 26. Observers will need a clear view of the western horizon to see the event. This is because they will be located low in the sky. The image below shows what the scene will look like from North America. Note that the Pleiades open star cluster will be located between Mercury and the Moon. It will be a great sight via your eye or binoculars. In a telescope, Mercury will appear as a fat crescent with ~36% of its disk illuminated.

Map of the Moon-Mercury-Pleiades conjunction on the evening of April 26. Map made with Stellarium.

Two Reasons to Wake Up Early Wednesday Morning

Reason #1 …

On the morning of April 22, the Moon will occult (or pass in front) of Venus for observers in most of North America. This event happens in daylight for most people. Only observers roughly west of the Rockies will see it in a dark sky. The below map from the International Occultation Timing Association (IOTA) shows where the occultation will be visible. Times for the beginning and end of the occultation can be found at IOTA’s site. A map showing time of disappearance and reappearance can be found at Science@NASA.

Venus and the Moon will rise around ~4 am local time in the east. It will help if you have a clear eastern horizon since all of the action will occur close to the horizon. [Added Apr 21: This morning I was up at ~5 am similar to the time when the occultation will start this morning. In Tucson at 5 am, twilight has already started. Still the sky is dark enough that the Moon and Venus are obvious. I didn't appreciate how low Venus is though. It was just barely visible between the trees. You may have to find a clear view of the eastern horizon to see the show.]

The following diagram gives a good representation of what the occultation will look like right before the Moon passes in front of Venus on the morning of April 22. Note that Mars will be located nearby as well. For those with binoculars or a telescope, Venus will appear as a thin crescent similar to, but much smaller than, the Moon.

The Moon, Venus and Mars just before the start of the occultation of Venus on the morning of April 22. Sky map produced with Stellarium.

Even if you can’t see the occultation, the close proximity of the Moon and Venus will appear awe inspiring. For those who want a nice challenge, try spotting Venus in broad daylight near the Moon. Venus is more than bright enough to be seen in a clear daylight sky assuming you know exactly where to look. Luckily the nearby Moon can help guide you.

Reason #2 …

The first few months of the year usually bring few meteors. After the excitement of early January’s Quadrantids there are no major showers for the next 3 months. This month the drought ends as the Lyrids, and in 2 weeks the Eta Aquarids, bring some much welcomed meteor “rain”.

The Lyrids are usually classified as a major shower though they are just barely so. They can be considered the weakest of the major showers or the strongest of the minor ones. They are produced by Comet Thatcher, a comet on a ~400 years orbit that has only been observed in 1861. The Lyrids, on the other hand, can be seen every year.

Comet Thatcher was discovered by American Professor A. E. Thatcher on April 5, 1861, only a week before start of hostilities in the US Civil War. Thatcher discovered the comet from New York City. Back in those days, light pollution was not a problem and the sky was dark even in the middle of major cities. One wonders if NYC will ever be the host any more comet discoveries. A short piece in the New York Times published on Feb. 28, 1870 contains a private letter sent from Sir John Herschel to Professor A. E. Thatcher. The letter was published nearly a decade after the discovery but shows the excitement in having a local scientist being personally congratulated by one of the world’s eminent astronomers of the time.

Thatcher first detected the comet as a 7thmagnitude object with no tail in the constellation of Draco. The comet brightened to magnitude 2 or 3 a month later as it passed closest to Earth at 0.34 AU on May 5. At the time the comet was an easy naked eye object with a 1 degree long tail. Perihelion occurred on June 3rd at a distance of 0.92 AU from the Sun. The parent of the Lyrids was last seen on Sept. 7, 1861. [Ref: Cometography, Volume II and Comets - A Descriptive Catalog, both by Gary Kronk]

The Lyrid meteors have been known for thousands of years. The earliest definite observation of the Lyrids goes back to 687 BC China. Many additional metoer displays in 11th and 12th centuries have been linked to the Lyrids. One of the best displays occured in 1803 when an observer noted 167 Lyrids in only 15 minutes. The last great Lyrid outburst happened in 1982 when 3-5 Lyrids per minute were seen. The next Lyrid outbursts are predicted for 2040 and 2041. Regardless, our understanding of meteor stream dynamics is still poor and a major outburst could happen in any year making yearly observations important.

This year the Lyrids are predicted to peak at 11 hour UT on the morning of April 22. The timing is great for the Americas which should see rates of ~15-25 meteors per hour. (These rates are only valid for observers under dark rural skies and when the radiant is nearly overhead.) Rates should be above ~10 per hour for a 24 hour period centered on the peak. A live plot of visual Lyrid rates from the International Meteor Organization can be found here.

Like most meteor showers, the Lyrids are best observed early in the morning a few hours before dawn. If you don’t want to get up that early, meteors can be seen, in diminished numbers, anytime after ~11 pm. The radiant is located between the constellations of Lyra and Hercules just to the west of the bright star Vega.

The sky at ~4:00 am on the morning of April 22 (valid for North America). The radiant of the Lyrids is overhead and denoted by the yellow starburst pattern. Star chart created with Stellarium.

When you see a Lyrid, what are you actually seeing? You regular run-of-the-mill Lyrid is a small piece of dust that was ejected from the nucleus of Comet Thatcher many hundreds to thousands of years ago. The reason why the meteor “burns” up in the atmosphere is due to the friction caused by its rapid velocity. The Lyrids strike the Earth’s atmosphere at 49 km/s or 30 miles/second.

In The Sky This Month – 2009 April

This feature highlights a number of meteor showers, comets and asteroids which are visible during the month of April 2009. The month sees the return of the borderline major meteor shower, the Lyrids. The highlight of the month is the lunar occultation of Venus right before dawn on April 22.

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 - This month brings us the best opportunity of the year to observe Mercury in the evening sky (for Northern Hemisphere observers). Mercury will be at its highest on April 26, though even then it will be low in the western sky 30-60 minutes after sunset.

The Moon will also located just above Mercury on the evening of April 26. The image below shows what the scene will look like from North America. Note that the Pleiades open star cluster will be located between Mercury and the Moon. It will be a great sight via your eye or binoculars. In a telescope, Mercury will appear as a fat crescent with ~36% of its disk illuminated.

Map of the Moon-Mercury-Pleiades conjunction on the evening of April 26. Map made with Stellarium.

Saturn – Saturn is the only planet visible in the evening sky. By the end of twilight, Saturn is high in the southeast under the eastern part of the constellation of Leo.

This year Saturn is dimmer than usual. At magnitude +0.6 to +0.7, there are at least 11 stars that are brighter than it. The reason is that the rings of Saturn contribute a lot  to the brightness of Saturn. But this year, is a ring plane crossing year meaning that the rings are nearly edge-on. As a result, the rings are reflecting much less light in the Earth’s direction this year. Saturn’s appearance through a telescope will match the below image taken by Bob Lunsford on March 28. Note the small dark spot near the top edge of Saturn’s disk, this is a shadow cast by Saturn’s largest moon, Titan.

Image of Saturn by Bob Lunsford from 2009 March 28. Titan's shadow seen near top.

The Moon will pass a relatively distant 5.5 degrees to the south of Saturn on the evening of April 6.

Venus - After spending the past few months dominating the evening sky, Venus will now spend the rest of the year as a morning object. If you live south of the Equator, Venus will appear to rocket higher and higher every morning. In fact it should be an easy sight by the 2nd week of April if you have a clear eastern horizon. Venus will reach its highest in late May.

For those of us north of the Equator, Venus will take a little longer to gain altitude. Though it is already visible for observers with a clear eastern horizon, Venus will slowly climb higher every night. For  northern observers, Venus won’t reach its highest till August. Regardless of where you are observing, Venus will be at its brightest on April 29 though it is always a very bright object.

For binocular and telescope users, Venus will start the month as a large thin crescent, 59″ across and only ~2% illuminated. By mid-month, it will have shrunk to ~50″ across but it will also become a fatter crescent with ~12% of the disk illuminated. By the end of the month, it is 39″ across and 25% illuminated

Venus is also involved in the coolest event of the month. On the morning of April 22, the Moon will occult (or pass in front) of Venus for observers in most of North America. The below map from the International Occultation Timing Association (IOTA) shows where the occultation will be visible. Times for the beginning and end of the occultation can be found at IOTA’s site. I’ll write more about this as the date draws closer.

The following diagram gives a good representation of what the occultation will look like right before the Moon passes in front of Venus on the morning of April 22. Note that Mars will be located nearby as well. For those with binoculars or a telescope, Venus will appear as a thin crescent similar to, but much smaller than, the Moon.

The Moon, Venus and Mars just before the start of the occulatation of Venus on the morning of April 22. Sky map produced with Stellarium.

Jupiter - Jupiter rises a few hours before sunrise. Other than Venus, it is the brightest “star” in the morning sky at magnitude -2.2. Due to Jupiter’s location in the southern constellation of Capricornus , it never gets very high this year.

Mars – Mars can be seen very low in the eastern sky all month long. At magnitude +1.2, it is only as bright as some of the brighter stars. Venus will pass a distant 5.5 degrees to the north of Mars on April 24. As a result, Mars will be located just below the spectacular Moon-Venus occultation.

Meteors

The month of March experiences no major showers and only a few minor ones. It continues the annual lull in meteor activity from mid-January to mid-April.

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 April, 8 or so Sporadic meteors can be observed per hour from a dark moonless sky.

Major Meteor Showers

Lyrids (LYR)

April brings the first major meteor shower since the Quadrantids in early January. The Lyrids are produced by Comet Thatcher, a comet on a ~400 years orbit that has only been observed in 1861. The Lyrids, on the other hand, can be seen every year.

The radiant is located between the constellations of Lyra and Hercules. Though the radiant rises during the evening, the best time to see Lyrids is after 11 pm when the radiant is high in the sky.

The shower is active from April 16 to 25 with a peak on the morning of April 22. The shower only shows good levels of activity on the night of the peak. Even then, this is the most minor of the major showers with a peak rate of ~15-25 meteors per hour.

Though there are no predictions on enhanced activity, the Lyrids have been known to put on grand displays. The 1st great display goes back almost 25oo years while the last happened in 1982. So you never know, this year could be the next good display.

Minor Meteor Showers

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

Pi Puppids (PPI)

The Pi Puppids are usually a very low activity shower. In 1977 and 1982, the shower put on a good display with up to 60 meteors per hour being observed. This shower radiates from the far southern constellation of Puppis and can not be seen from most of North America and Europe.

We now know that the Pi Puppids are created by Comet 26P/Grigg-Skjellerup. P/G-S is a small Jupiter family comet that orbits the Sun once every 5.3 years.

There are no predictions for enhanced material this year. The shower is active from April 15-28 with a peak on April 23. At its best we should expect 1-2 meteors per hour with even that number being optimistic for northern observers.

Eta Aquarids (ETA)

The Eta Aquarids are a major shower, especially for southern hemisphere observers, when they peak on May 5. During the month of April, the shower can be considered a minor shower.

The ETA were produced by Comet Halley which also gives us the Orionids in October. Models suggest that the ETA were released by Comet Halley no later than 837 AD. The Orionids are easy to see because the particles are hitting the Earth from the anti-solar direction. This means the meteor shower can be seen in the middle of the night. The ETA are produced by meteoroids moving outbound from the Sun, as a result the radiant is located relatively close to the Sun. This means that the ETA radiant is only visible for an hour or so before twilight.

The shower spans from April 19 to May 28 with a peak around May 5 with a maximum ZHR of ~60. The last week of April will see some low activity (ZHR < 10) from the ETAs.

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)

None

Binocular Comets (V < 8.0)

None

Small Telescope Comets (V < 10.0)

Comet C/2009 E1 (Itagaki)

This recently discovered comet was found by amateur astronomer Koichi Itagaki of Yamagata, Japan. Comet C/2009 E1 (Itagaki) is a long-period comet which will come within 0.60 AU of the Sun at perihelion on April 7. It is also periodic in that it returns once every ~250 years according to the latest orbit.

This is the 1st comet to bear Koichi Itagaki’s name but it is not his 1st discovery. Back in 1968, he was a co-discoverer of Comet Tago-Honda-Yamamoto. Due to the rule that only the 1st 3 discoverers can have their name attached to a comet, his name was left off. Only a few months ago, he also re-discovered long-lost comet Giacobini.

The comet is located in the evening sky north of the constellation of Aries. As the month progresses the comet will move north of the Sun as it travels through Triangulum, northern Pisces and Andromeda. Only observers with a clear view of the northwestern horizon in the evening and northeastern horizon in the morning will be able to see the comet. By May the comet will only be visible in the morning sky and will be much easier to see.

At magnitude ~8.0 to 8.5, the comet is bright enough to be seen in a reasonably sized backyard telescope. Having said that, I was just barely able to see it from my backyard in Tucson with my 12″ telescope due to the city lights and the bright twilight.

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

A nice collection of images can be found at the VdS-Fachgruppe Kometen (Comet Section of Germany).

Comet C/2009 F6 (Yi-SWAN)

A new comet has been discovered that should be the brightest comet in the sky this month. Comet C/2009 F6 (Yi-SWAN) is a long-period comet which will pass within 1.27 AU of the Sun on May 8. The comet is currently around magnitude 8.5 making it bright enough to be seen in small telescopes. Right now the nearly Full Moon will make observing the comet difficult but in a few days the Moon will not be a problem for evening observers. The comet is located north of the Sun. For southern hemisphere observers, you are out of luck. For northern observers, the comet can be observed in both the evening and morning sky.

Currently the comet is located in Cassiopeia. It is moving to the east and will enter Perseus by mid-month. The comet should continue to brighten as it approaches perihelion and may be as bright as magnitude 8.0.

On the morning of April 21, I was able to observe Yi-SWAN with 30×125 binoculars. My observing location isn’t too dark with a limiting magnitude of ~+5.5. Even then, the summer Milky Way was faintly visible. The comet was barely visible as it was large and diffuse. Interestingly, the comet was not visible during multiple attempts to observe it during the evening hours. The darker morning sky most definitely helped.

The comet was found by Dae-am Yi of Yeongwol-kun, Gangwon-do, South Korea on March 26. He noticed the obvious blue-green glow of a comet on 2 images he took with a Canon 5D digital camera and a 90-mm f/2.8 lens. The other discoverer was Robert Matson of Irvine, CA. Mr. Matson found the comet on a series of images taken with the SWAN instrument on the SOHO (Solar Heliospheric Observatory) spacecraft starting on March 29. The SWAN insturment images the entire sky for solar Lyman-alpha particles that are backscattered off of neutral hydrogen atoms. In this way, SWAN can monitor the activity of the far-side of the Sun. This instrument is also excellent at detecting the glow of hydrogan in the extended coma of comets.

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 fading after its closest approach to Earth in late February. It is a evening object and spends all of April moving westward through western Gemini. The comet starts the month around magnitude 8.5 and should fade to magnitude 10.0 or fainter by the end of the month.

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.

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 9.5 and will slowly brighten during the month.  It is moving near the border of Lacerta and Pegasus.  The comet is best seen in the early morning. I was able to observe the comet visually with my backyard 12″ reflecting telescope back 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 that 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.

On the morning of April 21, I was able to observe this comet with both 30×125 binoculars and a 12″ dobsonian. The comet was much easier to see in the 12″. Observation was made under a moderately light polluted sky with a limiting mag of ~+5.5.

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.

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 its surface. Ceres is one of two targets for NASA’s Dawn spacecraft which is scheduled to visit it in 2015. Last month Ceres was at opposition (at its closest to the Earth and at its brightest). This month Ceres will fade from from magnitude 7.4 to 8.0 as it ends is retrograde motion just north of Leo. If you are observing Saturn with a telescope or pair of binoculars, try your hand at finding Ceres with one of the finder charts linked below.

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 continues moving north, leaving the constellation of Orion and entering Monoceros. It fades from  magnitude 8.7 to 8.9 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.

(8) Flora

Flora is a large asteroid roughly 136×136x113 km in dimension. It is innermost large asteroid in the Main Belt. As a result, it can get bright enough for backyard observers with modest sized telescopes and binoculars. Flora is a stoney S-type asteroid and also the largest member of the Flora family. This family was created when a large impact occured on Flora. The other family members are pieces of Flora that were thrown off by the impact.

Flora starts the month at magnitude 10.0. It reaches its maximum brightness on April 22 at magnitude 9.8. By the end of the month, it has slightly faded to 9.9. Flora and Irene provide us with a 2-for since both objects are located within 5 degrees of each other.

Since there I have not been able to find a nice star chart showing the position of Flora, here is one I made with the C2A program. It also shows the position of Irene.

(14) Irene

Irene was discovered by John Russel Hind in 1851, being only the 14th asteroid known at the time (if you are wondering ~400,000 asteroids have been discovered to date, we’ve come a long way). It is an S-type asteroid with a stoney or silicate composition. Its takes 6.3 years to orbit the Sun.

This month Irene will brighten from magnitude 9.2 to a maximum of 8.9 on April 24 as it retrogrades through western Virgo. Remember Flora is located within 5 degrees of Irene.

(15) Eunomia

Discovered in 1851, Eunomia is one of the largest stoney S-type asteroids. Its dimensions are roughly 357×255×212 km. Similar to Flora, Eunomia is also the parent body of its own family.

Eunomia spends all of April in the constellation of Corvus, just to the south of Virgo. With opposition on April 2, the asteroid is as bright as it’s going to get this year at magnitude 9.8. As the month progresses it will fade to 10.0. This year Eunomia is at aphelion, its furthest from the Sun making this one of its faintest oppositions. When at perihelion, it can get as bright as magnitude ~8.

Since there I have not been able to find a nice star chart showing the position of Eunomia, here is one I made with the C2A program.

(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.

Amphitrite fades from magnitude 9.5 to 10.1 this month. It spends the entire month in eastern Virgo not far from Saturn. If you are observing Saturn, take a short star-hopping trip to Amphitrite

Since there I have not been able to find a nice star chart showing the position of Amphitrie, here is one I made with the C2A program.

Check Out the Moon and Venus Tonight (… and Comet Lulin) – Feb 27

Based on the number of comments I’ve been receiving, many people have been enjoying (or at least startled) by the grand display Venus has been putting on for the past few months. Tonight may be the best display yet as a very thin crescent Moon will join Venus.

This evening the Moon and Venus will be within 1.2 degrees of each other (for comparison the Moon is about 0.5 degrees across).

Moon and Venus in conjunction on the evening of Feb 27. Image created with Stellarium (www.stellarium.org).

While you are observing the two, there are a few fun things to watch out for. One, even though the Moon is a thin crescent, can you see a faint glow from the rest of the Moon? Your eyes aren’t deceiving you, what you are actually seeing is called Earthshine. If you were standing on the nightside of the Moon right now you would be seeing a Full Earth. Just like the Full Moon on Earth, the Full Earth is very bright. In fact, it is much brighter than the Full Moon since the Earth is bigger and more reflective. So just like on Earth where the landscape is illuminated by the Full Moon, we are seeing the same phenomenon on the Moon.

Second thing to look for, if you have a pair of binoculars or a telescope (any size will do) check out the shape of Venus. Venus is also a thin crescent and is shaped  very similar to the Moon. Below is a picture of Venus that I took through my 12″ telescope on the evening of Feb25. Venus will still look pretty much the same tonight.

The image below was taken by myself with a 12″ reflector and DMK 41AF02 camera on the evening of Feb 25.

Again if anybody gets some cool pictures of the pair and would like to share them with other blog readers, post a link in the comments section and I will include them in a future posting.

As for Comet Lulin, the comet still remains bright enough to be seen without optical aid if you live at a very dark site. For the rest of us, a nice pair of binolculars will suffice. Tonight the comet is easy to see as it is located just to the west (or right) of Regulus, the brightest star in Leo. It is best to wait until after 8:30 pm when the comet has risen high enough above the eastern horizon to be seen.

Sky chart showing the position of Comet Lulin and Saturn for 9:30 pm on the night of Feb 27. Chart produced with the Stellarium software (www.stellarium.org).

Jan 7/8/9/10 Meteors and a Big Full Moon

This weekend’s Full Moon will be the biggest and one of the brightest of 2009. This is caused by the Moon’s orbit which is not a perfect circle. This month, the Moon will be closest to the Earth (what we call perigee) today at a distance of 214,500 miles  (357,500 km). At its furthest (called apogee) on Jan 23 UT, the Moon will be 243,669 miles (406,115 km) away. That’s a difference of 29,169 miles (48,615 km) or ~14%. Due to the way the Moon’s orbit is lined up, Full Moons in December and January are the largest while the ones in June and July are the smallest. Also the Full Moons in December and January travel the highest in the sky for observers in the Northern Hemisphere. For more on this month’s large Full Moon, see this Science@NASA article.

The Full Moon means that it is real hard to observe meteors right now. Still the Tucson based SALSA camera system is still picking up 12-20 meteors per night. Most are Sporadics not affiliated with any particular shower, though a few Antihelions and Coma Berenicids can also be seen.

From Bob’s notes on Jan 7/8: “The weather here cannot make up its mind whether to be good or bad. Every other night seems clear recently. As for the meteor rates, they were downright pitiful on the morning of the 8th. Although the moon was bright, a total of 27 is far below expectations for my system, even in January.”

Obs  Date (UT)   TotTime TOT SPO ANT COM
TUS  2009-01-10  11h 00m  17  15  0   2
SDG  2009-01-10  10h 57m  28  24  2   2
TUS  2009-01-09  11h 38m  13  12  1   0
TUS  2009-01-08  12h 05m  18  17  0   1
SDG  2009-01-08  11h 55m  27  24  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)
ANT – Antihelions
COM - Coma Berenicids

Oct 13/14 Meteors

Last night was nice in clear in Tucson. Even with the almost Full Moon, 21 meteors were picked up including a nice bright Tau Ursa Majorid. Though only one object was recognized as a TAU, there were 3-5 meteors that appeared to originate near the TAU radiant. Unfortunately, Bob was experiencing camera problems and was not able to get any data to confirm whether the TAU radiant was more active than usual last night.

Tonight is Full Moon. In fact, tonight’s Full Moon is called the Hunter’s Moon. More on the significance of the Hunter’s Moon can be found at Wikipedia and Spaceweather.com.

Obs  Date (UT)   TotTime TOT SPO NTA STA ORI TUM EGE
Carl 2008-10-14  10h 56m  21  14  2   0   4   1   0

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 – Northern Taurids
STA – Southern Taurids
ORI – Orionids
TUM – Tau Ursa Majorids
EGE – Epsilon Gemininds