K. Itagaki of Yamagata, Japan was photographing the night sky in Eridanus two days ago when Hitoshi Yamaoka of Kyushu University noticed an anomaly – a possible classic nova event. Just how big a jump in amplitude did this star make? Try at least seven magnitudes within hours… and Joe Brimacombe was on it.
According to AAVSO Special Notice #181 released on November 25, 2009, there could be a possible nova in Eridanus. "Central Bureau Electronic Telegram No. 2050 (Daniel W. E. Green, Ed.) announces the discovery of a possible nova in Eridanus, as reported by Hitoshi Yamaoka, Kyushu University, by K. Itagaki, Yamagata, Japan, at magnitude 8.1 on images taken Nov. 25.536 UT. The object was confirmed by Itagaki on an image taken on Nov. 25.545.
Coordinates: R.A. = 04:47:54.21 Decl. = -10:10:43.1 (equinox 2000.0)
According to CBET No. 2050, "Itagaki notes that there is a faint (mag about 15) object near this position on his archival patrol images. Yamaoka suggests that it might be the brightening of a 15th-mag blue star that is contained in many catalogs (USNO-B1.0 position end figures 54s.19, 42".9), noting that the amplitude of seven magnitudes is rather large for a dwarf nova, but somewhat small for a rapid classical nova. Yamaoka adds that the ASAS-3 system (Pojmanski 2002, Acta. Astron. 52, 397) also detected this object at the following V magnitudes: Nov. 10.236 UT, [14.0:; 19.241, 7.34; 22.179, 7.98; 24.269, 8.12." Finder charts for this object may be plotted using VSP by entering the coordinates into the form at the this URL.
This object has been assigned the VSX identifier VSX J044754.2-101043. An AUID will be assigned by the VSX moderators and will be added to the on-line version of this notice when it becomes available. Please report observations to the AAVSO International Database as N ERI 2009 or VSX J044754.2-101043."
Within 24 hours even more news came in via AAVSO Special Notice #182:
"This new variable object in Eridanus, originally called a possible nova in CBET 2050, is most likely a WZ Sge variable. It matches closely the coordinates of GSC1.2 05325-01837, listed in that catalog at 14.76 mag. At the peak outburst magnitude of 7.3, this is about 7.5 magnitudes amplitude, within the range of a galactic variable and lower than a typical nova. It appears to be fading and is about V=8.5 right now. However, WZ Sge cataclysmic variables have a complex light curve and the star may re-brighten. We are awaiting spectral
confirmation and possible GCVS naming, and will pass on that information as soon as possible.
As mentioned in Special Notice 181, the star has been entered as VSX J044754.2-101043 and now has an AUID of 000-BJR-847. You can submit observations to the AAVSO with either identifier. We have a preliminary sequence from Mati Morel, and have obtained BVRI imagery using the Bright Star Monitor at Astrokolkhoz Observatory
which we will use to construct a multiwavelength sequence tomorrow (November 27).
This is a good target for time series photometry, and at its current brightness, we highly recommend using filters. Larger telescopes should consider B or even U filters."
Congratulations to K. Itagaki on his latest discovery, to AAVSO for pinning it down and to Joe Brimacombe for his quick imaging of the phenomena!
Most meteor showers vary from year to year, but the Leonids are particularly capricious. Many years they chug along producing just 5 or 10 meteors visible per hour. But at the Leonids' historical greatest, in 1833, meteors were seen to fall "like snowflakes in a blizzard," with estimated rates of several dozen per second!
This year is expected to be better than average. The "traditional," most reliable part of the shower should peak around 4 a.m. EST (1 a.m. PST) on the morning of Tuesday, November 17th. You might see 20 or 30 meteors per hour under ideal dark-sky conditions. (Remember, if you want to stay up late instead of getting up early, you'll be staying up Monday night. It's easy to get the date wrong for events that happen after midnight!)
A second, briefer, but very intense outburst is expected about 12 hours later — during the early-morning hours of November 18th in Asia. (See "Will the Leonids Roar Again?".) There's only an off-chance that some activity from that burst will still be going on by the time the Earth turns halfway around and the Leonids become visible in the Americas on the morning of the 18th.
But if the sky is clear, why not go out again that morning — and also before the predicted peak, on the morning of the 16th? The Leonids have surprised the theorists before, and they surely will again.
Wherever you are, no Leonids will be visible before the shower's radiant point (in Leo) rises around local midnight. And peaks and bursts aside, the number of visible meteors increases steadily from radiant-rise until Leo is highest, just as the sky is starting to get light.
Be sure to bundle up warmly; meteor-watching is always colder than you expect. Ideal meteor-watching equipment is a comfortable lounge chair, a warm sleeping bag, and a pillow. If you live in a city or suburb, consider traveling to a dark location far from city skyglow. In any case, find a spot where no lights glare directly into your eyes.
The direction to watch is wherever your sky is darkest. Notice the meteors' flight paths; only those streaking away from the direction to the constellation Leo are Leonids.
Another, less-known meteor shower is going on simultaneously — the Taurids. They're sparse but tend to be very bright. If you see a slow, bright meteor heading away from the direction to Taurus, that's a Taurid.
And you're bound to see a few sporadics that aren't associated with any major shower.
The longest solar eclipse was watched by hundreds of people including school students at ASTRO observatory Payyanur. Even though clouds cast shadows over crowd gathered here till 6.45 am. Then the sun came out of clouds to show the cosmic drama of eclipse. ASTRO coordinator K Gangadharan Master gave class and instructions for the people gathered
For the second time in a year, a total eclipse of the Sun is about to cross China. But unlike the Moon's hard-to-reach shadow path last August, the celestial spectacle on July 22, 2009, will darken major cities, densely populated countryside, and a vast expanse of tropical ocean. And the eclipse itself will be a monster, with totality lasting more than 6.6 minutes at maximum. That makes this the longest totality until 2132.
A total solar eclipse occurs once every year or two on average, but each is visible only from a narrow track covering less than 1% of Earth’s surface. The eclipse of August 1, 2008, was visible only from parts of the Arctic, Siberia, and central Asia. Nevertheless, thousands of enthusiasts traveled by land, air, and polar icebreaker for the chance to bask briefly in the silvery twilight glow of the Sun’s corona.
The main reason why this year's totality lasts so long is because the eclipse starts just a few hours after the Moon reaches perigee. At such a close distance, the Moon appears fully 8% larger than the Sun and casts a broader than usual shadow. At the point of greatest eclipse in the western Pacific, the path of totality is 258 km (161 miles) wide.
The umbra (dark central portion) of the lunar shadow first touches Earth at sunrise at 00:53 Universal Time in the Gulf of Khambhat off western India. The shadow takes just 8 minutes to cross India before spilling into northern Bangladesh and easternmost Nepal. A minute later the umbra engulfs most of Bhutan, while the eclipse duration on the central line crosses the 4-minute mark. The Sun’s altitude is 21°.
The shadow then crosses northern Burma, a corner of Tibet, and China’s Yunnan province. Passing through the middle of Sichuan province, the eclipse track darkens the capital city of Chengdu (2 million inhabitants, 3.3 minutes of totality), Chongqing (4.1 million, 4 minutes), and Wuhan (9.7 million, 5.5 minutes). Traveling nearly due east, the shadow track encompasses the meandering course of the Yangtze River.
Near the Pacific coast, Hangzhou's 4 million citizens experience a total eclipse lasting 5.3 minutes. The Sun’s altitude is now 55°. A minute later Shanghai, China’s largest city with 20 million people, plunges into totality for 5 minutes, though it is well north of the central line. This may be the most people that have ever been in the Moon’s shadow at once.
As it moves out over the East China Sea, the umbra sweeps over Japan’s Ryukyu Islands, then Iwo Jima and Kitaio Jima, before curving southeast across the Pacific. The instant of greatest eclipse occurs at 2:35:19 UT, when totality lasts longest: 6 minutes 39 seconds. This happens over open ocean with no land in sight.
The second half of the eclipse path crosses nothing but ocean and a few tiny islands and coral atolls among the Marshall Islands and Kiribati. The total eclipse finally ends at 4:18 UT, at sunset about 1,000 km northwest of Tahiti. The Moon’s shadow lifts off Earth and returns to space, after covering 0.7% of Earth’s surface in 3.4 hours.
Future Total Eclipses
On July 11, 2010, this part of the world will be favored with its third total solar eclipse in as many years. The track is almost entirely over the South Pacific. Easter Island and southern Chile (at sunset) offer the only landfalls. And the South Pacific also hosts the next one, on November 13, 2012.
A total solar eclipse won’t cross the Americas until August 21, 2017, when the Moon’s umbra will sweep from Oregon to South Carolina.
Novae explode without warning, and even recurrent novae are pretty unpredictable. (For instance, we've been waiting way too long for T Pyxidis to erupt again
But here's a prediction about a recurrent nova that should go off in a specific year: 2009. I've calculated that the recurrent nova U Scorpii, north of Antares and east of the head of Scorpius, should explode any month now. My "crystal ball" is based on old archival photographs and data from amateur astronomers. This brings a golden opportunity for amateurs and professionals to catch the early hours of a nova eruption and to prepare in advance for an intensive observing campaign.
"Recurrent novae" are those that have had more than one eruption observed within a century or so. Classical novae too are believed to repeat, but on timescales of perhaps 1,000 to 100,000 years; we just haven't been watching long enough to see them do it yet.
U Sco is one of the most famous recurrent novae. In quiescence it usually hovers around magnitude 17.6, but in outburst it briefly shoots up by about 8 or 9 magnitudes. In fact, U Sco is the all-time fastest nova known. Its brightening from minimum to maximum takes only about 5 hours, and its decline to two magnitudes below maximum takes about 38 hours. U Sco's last three eruptions, in 1979, 1987, and 1999, were all discovered by amateur astronomers.
A Daring Pairing of Moon and Venus
Early risers in North America are in for a treat on the morning of Wednesday, April 22nd, when the waning crescent Moon passes in front of the brilliant crescent Venus.
Tracks for Venus occultation
The apparent path of Venus behind the Moon on April 22, 2009, depends on where you are. The local horizon is approximately downward; celestial north is to the upper left.
Sky & Telescope
For much of the continent the occultation happens after sunrise in broad daylight. If the air is clear you can find the thin, dim Moon about 33° to the upper right of the early-morning Sun, with Venus near its edge. Sadly, this event will be a near miss along the Eastern Seaboard.
I'm tempted to hop a westbound plane, because in the Far West the occultation happens during morning twilight — with the Moon and Venus shining beautifully before sunrise but very low above the eastern horizon. When the Moon covers Venus they'll be only 6° up as seen from Los Angeles, 4° from San Francisco, and 6° from Seattle. When Venus reappears at these locations the Moon will be about 10° higher, with the Sun already risen or nearly so.
Because the Moon is waning, its bright edge will be the one that covers Venus and its dark limb will uncover it, as shown in the diagram above. The thin crescent Moon will be only 9% sunlit, while Venus (40 times smaller) will be a 17% crescent.
At locations where the sky is still fairly dark, all you'll need are your eyes to watch this celestial spectacle. You'll probably need binoculars or a telescope where the sky is bright. Because of Venus's significant angular size, its disappearance and reappearance will each be gradual, taking 30 seconds or more.
You can gauge the approximate times of Venus's disappearance and reappearance at your site using the maps below. Interpolate between the red time lines to get the Universal Time of the event. Along the graze line, you'll see the Moon's southern limb skim Venus but never quite cover it. The maps also indicate whether your location will be in twilight or daylight at this time. (You can get customized predictions for several hundred cities and towns here.)
Maps of Venus's occultation
Use these maps to estimate the Universal Times of Venus's disappearance and reappearance during its occultation by the Moon on April 22, 2009.
Sky & Telescope diagram
And if you're willing to get up a few hours earlier, you might be treated to a nice smattering of "shooting stars" from the annual Lyrid meteor shower. In most years you'll see fewer than 20 Lyrids per hour before the first light of dawn even under perfectly dark skies. But some years have brought outbursts of up to 90 per hour. Will 2009 be one of those?
A small 8th-magnitude comet is now making its way slowly across Cassiopeia toward Perseus. The surprise visitor, called Comet Yi-SWAN, should be within reach of small telescopes for most of April and May 2009. However, bright moonlight will make it a challenge to spot until the second half of April.
So far, observers describe the comet as a diffuse glow just a few arcminutes across. No one has yet reported a tail, but that could change in the coming days as the Moon's glare wanes.
Because of its high declination, Comet Yi-SWAN is theoretically visible all night from mid-northern latitudes. But early rising skywatchers have the best chance, because Cassiopeia is highest during the predawn hours.
On Saturday evening, April 11th, the comet passes just 0.4° south of Schedar (α Cassiopeiae), so they'll be in the same low-power telescopic field. On Thursday night, April 23-24, the comet will glide only 1.2° south of the Double Cluster in Perseus.
The Discovery
Korean amateur Dae-am Yi was the first person to notice the comet. On March 26th, he obtained two images of it with a Canon 5D camera and 90-mm lens. But word was slow to reach the Central Bureau for Astronomical Telegrams (CBAT) at the Smithsonian Astrophysical Observatory in Cambridge, Massachusetts, the world's clearinghouse for comet discoveries.
Independently, Rob Matson reported to CBAT on April 4th that he'd found a possible comet in SWAN images posted on the SOHO website.
Recognizing that the objects were one and the same, CBAT astronomers announced the find on IAU Circulars 9034 and 9035 and gave it the name Comet Yi-SWAN (C/2009 F6). Preliminary calculations by Brian G. Marsden indicate the comet is traveling in a highly inclined parabolic orbit, tipped 85.7° to the plane of the ecliptic. At perihelion on May 8th, the comet will be 1.27 astronomical units (190 million km) from the Sun and half again farther from Earth.
The ephemeris below, from Marsden's orbital elements, gives the comet's right ascension and declination (equinox 2000.0) at 0 hours Universal Time on selected dates, along with its elongation angle from the Sun, predicted visual magnitude, and the constellation in which it lies.
This week's sky
Early April is the best time for viewing another favorite saturnian moon, Iapetus. This two-faced moon has one hemisphere as bright as snow and one as dark as charcoal. The bright side faces Earth when Iapetus lies far west of Saturn, and the dark side points toward Earth when the moon appears far east of the planet. The upshot: Iapetus' brightness changes by a factor of five as it orbits Saturn. The moon shines at its brightest when it reaches greatest western elongation April 2. It then glows at magnitude 10.1.
No other planet rises until well past midnight. The first to appear is Jupiter, which leads the pack of three other planets -- Neptune, Venus, and Mars -- congregating in the morning sky. At magnitude -2.1, Jupiter shines far brighter than any other object in the dim region of sky inhabited by Capricornus. It rises by 5 a.m. local daylight time April 1.
This week's sky
Meteor activity remains low during March. The only shower is a minor one deep in the southern sky. Still, you might see fine meteor dust in the form of the zodiacal light. This faint glow shows up best from dark observing sites during the moonless evenings after mid-March. Well after the Sun sets, twilight's last gleaming will give way to a lingering cone-shaped glow - the zodiacal light. The glow extends up through Aries and into Taurus.
The zodiacal light represents sunlight reflecting off dust particles concentrated along the ecliptic, the plane of our solar system. Because the dust lies in the ecliptic plane, the glow follows the constellations of the zodiac (hence the name). The glow shows up best when the ecliptic makes a steep angle to the horizon. In the Northern Hemisphere, this happens on evenings in early spring.
If you have a telescope, mark April 2–5, 2009, on your calendar. The world is coming your way.
An unprecedented string of public skywatching events will be packed into this brief period, all designed to engage people and bring them out for a worldwide star party that will cap the program on Saturday evening, April 4th.
Collectively, the period is called “100 Hours of Astronomy.” It’s a Cornerstone Project of the International Year of Astronomy 2009, tailor-made for amateurs who’d like to try some outreach. During the final 24 hours a global star party will sweep around the world, with local gatherings beginning as darkness descends. Even city street corners will come alive, with the third annual International Sidewalk Astronomy Night happening the first weekend in April. Thus many sidewalk astronomy regulars will already be at their stations.
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Saturn lies opposite the Sun in our sky March 8, which keeps it visible all night. Opposition also brings Saturn closest to Earth, so it shines brightest and appears biggest through a telescope. Saturn peaks at magnitude 0.5, making it the brightest object in its host constellation, Leo the Lion. The planet lies in southern Leo, beneath the Lion's hindquarters.
Comet Lulin this week is at its brightest and closest to Earth — right when the sky is conveniently moonless. Use binoculars or a telescope to look for it once it's well up in late evening. The comet is glowing at about magnitude 5.6 as it moves rapidly westward across Virgo.
In recent days the comet's dust-spike antitail has grown longer and stronger, completely outclassing its "true" tail, which points properly away from the Sun like a comet's tail should.
On Monday night, February 23rd, the comet passes 2° south-southwest of Saturn.
Lulin’s closest approach to Earth, 0.41 a.u. (61 million km), occurs on February 24th.
On the night of February 25th the comet goes through opposition, nearly 180° from the Sun in our sky. Will there be an "opposition effect" brightening of its dusty coma and dust tail? 
TAKE BACK THE NIGHT!
JOIN THE GLOBE AT NIGHT CAMPAIGN, 16-28 MARCH!
At least 2 out of 5 Americans, 1 out of 6 Europeans and 1 out of 10
people worldwide have never seen 90% of the stars in our night sky.
With half the world's population now living in cities, this problem is
only getting worse. Yet you can easily be part of a local solution to
a global problem.
Take back the night! Take a few minutes to monitor your local night
sky brightness, place your measurement on-line noting your location,
date and time and within a few weeks see a map of light pollution
levels worldwide.
Be part of the "GLOBE at Night" citizen-science campaign and make a
world of difference! The GLOBE at Night campaign runs March 16-28,
2009. Help preserve our natural heritage for generations to come. Find
out more information at www.globe.gov/globeatnight . GLOBE at Night is
an official International Year of Astronomy Dark Skies Awareness
cornerstone project.
100 hours of Astronomy is a 100-hour (from the 2nd to the 5th of April 2009), round-the-clock, round-the-globe event inside the International Year of Astronomy.
It consists of a wide range of public outreach activities, live science center, research observatory webcasts and sidewalk astronomy events. Events are mainly focused on the wonders of the starry night, but there are also events all around the world to observe the crescent Moon for early observer, and of course daytime observations of the Sun.
This Solar TG collaborates with 100 Hours, supporting any activity related to the Sun, and providing instructions, ideas and recommendations for safe solar observations.
And Sunday might perfectly be the best day for a solar event. Star parties on Sunday are difficult since everyone has to get up early for school or work. Let´s enjoy the Sunday, when everyone has free time and kids and adults can all enjoy the near but forgotten Sun and its wonders. Either get up early to start with a nice sunrise, go for a walk on the afternoon or enjoy a wonderful sunset. On the meantime you can participate on a 100 hours solar event. Ask your local astronomy center for more information. If you are an astronomy center, let´s organize one event!. There is no need to restrict it to the Sun, you can event start at sunset and continue with some star gazing…
Let the last day of 100 Hours be the Sun day, not just a Sunday.
For that reason, this page, and on the 100 hours website, we will be encouraging and helping everyone to organize their solar events this day. Here you can find, ideas, resources, experiments. Leave us our comments or ask us any question you might have.
Create your event! The perfect venue is outside, sunshine permitting.
* Always when observing the Sun, follow and educate everyone with safety instructions.
* Set up a telescope with a Solar filter, withe white light of H-Alpha.
* Create a pinhole camera to image the Sun, or better make a workshop to build your own pinhole camera.
* Talk, talk, talk. There are many many topics to talk about our Sun. Speaking about any of them, keeping the live shining reference above us, greatly helps to put closer the wonders and distant worlds of Astronomy. See below for a tentative lists of topics.
* There are many experiments to carry on, like
Measuring the Sun size, and others.
* Make a solar system play with kids (to talk about distances, speeds, sizes, space missions, …
* Construct an spectrometer with a CD.
* Show the photoelectric effect, use sun panels, talk about Solar energy.
* Make coordinated pairs of observations around the world to measure the Sun-Earth distance, or the Earth radius.
Take a look on our resources sections, there you can find links th more activities and experiments, as well as links with even more activities.
Indoors or outdoors, a thematic talk can be a very instructive idea. You can decide to do it just with your voice, or use media materials, like photos or videos (see below for references)
Thematics ( Brainstorming )
* Scales of the Sun, its dimensions, distances, inner parts, …
* Safety and the Sun. Observing the Sun, UV light, …
* Living on the Sun´s atmosphere, influences and safety and dangers due to the heliosphere.
* Space Weather: How the Sun can greatly influence the Earth. Magnetic storms, effects on technology, past solar maxima, dangers and protecting of the Earth´s magnetosphere.
* Current research efforts, satellites observing and serving live image of the Sun from many viewpoints.
* Current biggest misteries of the Sun, like the coronal heat.
* Use the Sun to talk about the life of a star.
* Talk about anecdotes related to the Sun, like the Carringtongs flare, the nuclear false positive, the little-ice age, Vancouver black out, telegraphy on the Sun batteries, proof of Einstein theories during an eclipse, the discovery of the Helium, …
* The Sun in history (from nature, life, to mythology, astrology, … )
* What if? cases: How would humans look like, or exists, if the Sun, were a bit bigger, closer, fainter, more active, calm, emitting more in X-rays or infrareds than on “Visible”, had a companion, Jupiter as a Sun…
* The brother Sun: The Sun and us, we all come from the same dust of a previous father Star.
* Ask an astronomer: Open tables to talk about the skies
Play some on the zillion on movies or documentals about the Sun, eclipses, …
Show the Live view from the Sun, like from Stereo, Hinode, Soho. Use videos of the Sun (Best of Soho, Hinode, Stereo, Trace), from the National Geographic, … (take a look to the resources pages for more links or send us your links!)
Ask your planetarium or science museum to prepare an astronomical event on that day.
Asteroid Ceres approaches Earth
February is a special occasion for the solar system's biggest asteroid. Not only is 1 Ceres making its closest approach to Earth since 1857, but it also will not get this close again for at least another millennium.
The long-term gravitational tugs of the planets conspire to modify Ceres' orbit just enough for this month's record-breaking event. Still, the difference between the asteroid's appearance now and at other favorable oppositions isn't huge. In 9 years, Ceres will be only 1.2 percent farther away.
You can follow Ceres through binoculars from your backyard. It sails through northern Leo during February, in a region without a lot of bright stars. Simply use the finder chart to pick out the pattern of nearby stars, then look for the interloper.
You may think this close approach will give you a chance to see Ceres without optical aid. You'd be right -- although not by much. At opposition, Ceres glows at magnitude 6.9 in a sparse starfield. Sharp-eyed observers under the darkest skies have seen objects this faint before. However, you'll have a better chance just 3 years from now. Ceres will then brighten to magnitude 6.7 thanks to the "opposition effect." The Sun-Earth-asteroid angle then will be closer to a straight line than during this month's slightly crooked arrangement. The better alignment in 2012 will increase Ceres' brightness more than the greater distance will decrease it.
On Friday Jan 30, 09 we are presented with a nice opportunity to catch Venus in broad day light.
On this day the Moon and Venus would be rising almost together. At about 10:00 a.m. if the sky is clear it should not be difficult to see the brightening lunar crescent well above the eastern horizon. Venus would be about two and quarter degrees south of the Moon. If one uses a small pair of binoculars one should be able to see these in the same field of view.
The best opportunity, however, comes when they will be crossing the meridian, an imaginary arc that passes through the north pole, the point right overhead and then the south pole. Close to the time is crosses the meridian (called transit time) time face due south and look strait up and then bend your neck down slightly southwards. You should be able to spot the Moon and then continue further down a bit and you can spot Venus.
Venus Rise, Transit and set times (in IST) for some cities in India are
rise transit set
Chennai 9h 01m 15h 12m 21h 26m
Bangalore 9h 25m 15h 27m 21h 28m
Jaipur 9h 32m 15h 34m 21h 36m
Kolkata 8h 42m 14h 44m 20h 46m
Mumbai 9h 44m 15h 46m 21h 47m
New Delhi 9h 26m 15h 28m 21h 30m
Pune 9h 39m 15h 41m 21h 43m
If you missed the event, never mind. Wait till it gets dark. It would be a magnificent view of the Moon and Venus next to each other above the western horizon.
Annular Solar Eclipse of January 26
The first solar eclipse of 2009 occurs at the Moon's ascending node in western Capricornus. An annular eclipse will be visible from a wide track that traverses the Indian Ocean and western Indonesia. A partial eclipse will be seen within the much larger path of the Moon's penumbral shadow, which includes the southern third of Africa, Madagascar, Australia except Tasmania, southeast India, Southeast Asia and Indonesia. (Figure 1).
The annular path begins in the South Atlantic at 06:06 UT when the Moon's antumbral shadow meets Earth and forms a 363 kilometre wide corridor. Traveling eastward, the shadow quickly sweeps south of the African continent, missing it by approximately 900 kilometres. Slowly curving to the northeast the path crosses the southern Indian Ocean. Greatest eclipse[1] takes place at 07:58:39 UT when the eclipse magnitude[2] will reach 0.9282. At this instant, the annular duration is 7 minutes 54 seconds, the path width is 280 kilometres and the Sun is 73° above the flat horizon formed by the open ocean. The central track continues northeast where it finally encounters land in the form of the Cocos Islands and onward to southern Sumatra and western Java (Figure 2). At 09:40 UT, the central line duration is 6 minutes 18 seconds and the Sun's altitude at 25°. In its final minutes, the antumbral shadow cuts across central Borneo and clips the northwestern edge of Celebes before ending just short of Mindanao, Philippines at 09:52 UT. During a 3 hour 46 minute trajectory across our planet, the Moon's antumbra travels approximately 14,500 kilometres and covers 0.9% of Earth's surface area. Path coordinates and central line circumstances are presented in Table 1.
Partial phases of the eclipse are visible primarily from southern Africa, Australia, Southeast Asia and Indonesia. Local circumstances for a number of cities are listed in Table 2. All times are given in Universal Time. The Sun's altitude and azimuth, the eclipse magnitude and obscuration[3] are all given at the instant of maximum eclipse.
This is the 50th eclipse of Saros 131. The family began with an unusually long series of 22 partial eclipses starting on 1125 Aug 01. The first central eclipse was total in the Northern Hemisphere on 1522 Mar 27. It was followed by 5 more total eclipses before the series produce 5 hybrid eclipses from 1630 to 1702. The first annular eclipse of Saros 131 occurred on 1720 Aug 04. The series will produce 29 more annular eclipses the last of which is 2243 Jun 18. Saros 131 terminates on 2369 Sep 02 after a string of 7 partial eclipses. Complete details for 70 eclipses in the series may be found at:
Launch Conference of the International Year of Astronomy
UNESCO, Paris, France, January 15-16 2009
2009 has been declared International Year of Astronomy by the General Assembly of the UN (United Nations Organization).
The Opening ceremony of the International Year of Astronomy will take place in Paris, January 15-16, 2009, under the aegis of the UN, the UNESCO (United Nations Educational, Scientific and Cultural Organisation), the IAU (International Astronomical Union). It is also supported by a number of sponsors including French and international organizations and institutions .
About 600 participants are expected, among them eminent scientists (including Nobel Prize winners), and also about 200 young students from over 100 countries, participating to the International Year IYA2009. Attendance is on invitation only.
Comets for both morning and evening
January lets us do an end run around the Moon's bright glare. When it washes out the sky near one interplanetary fuzzball, a second one comes into view on the sky's other side. Newcomer C/2007 N3 (Lulin) glides in the Moon-free morning skies during January's first 2 weeks, then the returning Comet 85P/Boethin becomes a prime evening target after midmonth.
Lulin tips the scales of Libra, between ruddy Antares and blue-white Spica. Glowing at 8th magnitude, this primordial snowball hails from the distant Oort Cloud. The comet makes its closest approach to the Sun January 10, but it will continue to brighten as it approaches Earth. It's destined never to return to the inner solar system. You'll need an 8-inch telescope to spy this comet from the suburbs, but a 4-inch will reveal it under a dark sky