CORONAL MASS EJECTION: During the late hours of July 30th, a magnificent coronal mass ejection (CME) billowed away from the eastern limb of the sun. Click on the image to set the cloud in motion:

If a CME like this hit Earth, polar sky watchers would likely see bright auroras. In this case, however, the cloud is not aimed in our direction. At most, it would deliver a glancing blow to Earth's magnetic field around August 2nd, producing only minor geomagnetic activity.

The source of the blast was apparently sunspot 1092. Future CMEs could be more geoeffective as the sunspot turns to face Earth in the days ahead. Stay tuned!

DEJA VU ERUPTIONS: On July 28th, magnetic fields on the sun's eastern limb became unstable and erupted, producing a towering prominence of surpassing beauty. On July 29th, it happened again. Click on the image to play a movie from NASA's Solar Dynamics Observatory (SDO):

movie formats: 7.5 MB gif, 1.4 MB iPad, 0.6 MB iPhone

Neither eruption produced a bright flash of X-radiation. For that reason, solar activity on July 28th and 29th was officially classified by NOAA's Space Weather Prediction Center as "low" to "very low." It might be time to change the classification scheme. X-rays have long been used as a key measure of solar activity, but SDO is revealing many forms of activity that do not emit strong X-rays. The spectacular eruptions of the past two days are good examples.

Déjà vu movies: July 28, July 28 slow-motion, July 29.

TOWERING BLAST: Yesterday, a magnetic filament curling over the southeastern limb of thee sun became unstable and erupted. The blast produced a towering curlicue prominence that "Dr Seuss would have loved," says Alan Friedman, who sends this picture from his backyard observatory in Buffalo, New York:

"It towered more than 200,000 miles above the stellar surface," says Friedman.

Astronomers around the world watched the structure twist, curl, and eventually fling itself into space over a six hour period. NASA's Solar Dynamics Observatory had the best view of all. Onboard cameras recorded an IMAX-quality movie of the event ... coming soon to a theatre near you? NASA is planning an IMAX movie about SDO, and this eruption will probably make the cut. Until then, enjoy these previews: 9 MB movie, 15 MB slow-motion movie.

more images: from Pete Lawrence of Selsey, West Sussex, UK; from David Evans of Coleshill, North Warwickshire, UK; from Steve Rismiller of Milford, Ohio; from A. Cote, S.Berube and J.Stetson of South Portland, Maine; from Patrick Bornet of Saint Martin sur Nohain, Nièvre, France;

SOLAR ACTIVITY: Readers with solar telescopes, train your optics on the sun's northeastern limb. A big sunspot with an active magnetic canopy is emerging there. And that's not all...  Today around 1200 UT, magnetic fields looping over the sun's southeastern limb became unstable and erupted. The blast produced a towering prominence dozens of times taller than Earth itself:

David Evans took the picture from his backyard observatory in Coleshill, North Warwickshire, UK. "This was a huge event," he says. "It just goes to show how the sun can surprise observers even at this 'low' phase of the solar cycle."  Stay tuned for movies of this event from the Solar Dynamics Observatory.

more images: from Alan Friedman of Buffalo, NY; from Pete Lawrence of Selsey, West Sussex, UK; from Steve Rismiller of Milford, Ohio; from A. Cote, S.Berube and J.Stetson of South Portland, Maine; from Stephen Ames of Hodgenville, Kentucky;

Current conditions Solar wind
speed: 579.4 km/sec
density: 1.8 protons/cm³
explanation | more data

Updated: Today at 2343 UT X-ray Solar Flares
6-hr max: C2 2040 UT Jul28
24-hr: C2 2040 UT Jul28
explanation | more data
Updated: Today at: 2340 UT

SUNSPOT 1089: The two dark cores of sunspot 1089 are each larger than Earth, and the whole region is criss-crossed by dark magnetic filaments. It's a photogenic ensemble:

"I like how the sunspots of new Solar Cycle 24 continue to get bigger and more complex as the cycle unfolds," says photographer Micheal Borman of Evansville, Indiana. "This picture was taken with my Televue 102iis refractor and a Coronado SM90 solar filter."

Although sunspot 1089 is big, it has not yet produced any flares of consequence. Perhaps it is gathering energy for a good eruption. Readers with solar telescopes are encouraged to monitor developments.

more images: from John Stetson of South Portland, Maine; from Peter Paice of Belfast,Northern Ireland; from Cai-Uso Wohler of Bispingen, Germany; from Peter Desypris of Island of Syros Greece;

ULTRAVIOLET SUNSPOT: Sunspot 1089 is churning out a lot of extreme ultraviolet (EUV) photons. Witness this EUV image taken just hours ago by the Solar Dynamics Observatory:

The bright glow comes from hot (80,000 K) plasma trapped by the sunspot's magnetic field. All by itself, this one 'hot spot' is lifting the EUV brightness of the entire sun toward a high point for the year. EUV photons from sunspot 1089 are absorbed in Earth's upper atmosphere where they heat the rarefied air and help reverse the recent collapse of the thermosphere.

Sunspot 1089 is still growing, both in brightness and area. Readers with solar telescopes are encouraged to monitor developments.

more images: from Etienne Lecoq of Normandy France; from Roman Vanur of Nitra, Slovakia; from Pavol Rapavy of Observatory Rimavska Sobota, Slovakia; from Steve Wainwright of Gower S.Wales UK

"Venus Point is where Capt. James Cook made his famous observations of the transit of Venus in 1769, so it is a historic spot for astronomy," explains Dyer. "This vertical shot shows all four evening planets, Mercury, Venus, Mars and Saturn; together they define the plane of the solar system, which in the tropics rises almost perpendicular from the horizon. It was a beautiful scene."

Apparently, missing an eclipse isn't so bad ... when you miss it in the South Pacific. Browse the gallery for views.

MAGNIFICENT ACTIVE REGION: Sunspot 1087 has a magnetic canopy that can only be described as magnificent. It's on full display in today's extreme ultraviolet image from the Solar Dynamics Observatory:

 The active region could swallow our planet ten times over and still have room to spare. Fortunately, we're 93 million miles away. We could still feel the effects of an eruption, however. The thicket of magnetic loops and filaments harbors energy for M-class solar flares. M-flares can heat and puff up Earth's upper atmosphere, causing satellites to experience extra drag as they orbit our planet; they can also cause waves of ionization to ripple around the planet, disrupting radio communications. There haven't been any big eruptions yet, but the magnificent magnetic field of sunspot 1087 has been restless, as shown in this time-lapse movie spanning four days.

NOAA forecasters estimate a 10% chance of M-flares during the next 24 hours. Readers with solar telescopes are encouraged to monitor developments.

ASTEROID FLYBY: Yesterday, July 10th, the ESA's Rosetta probe executed a close flyby of big asteroid Lutetia. Close-up photography reveals an alien terrain dented by a giant bowl-shaped depression with "asteroid-boulders" rolling down the sides. Must-see images here!

The images show that Lutetia is heavily cratered, having suffered many impacts during its 4.5 billion years of existence. As Rosetta drew close, a giant bowl-shaped depression stretching across much of the asteroid rotated into view. The images confirm that Lutetia is an elongated body, with its longest side around 130km.  
 

"I think this is a very old object. Tonight we have seen a remnant of the Solar System’s creation," says Holger Sierks, OSIRIS principal investigator, Max Planck Institute for Solar System Research, Lindau, Germany.
 
Racing past an asteroid
 
Rosetta raced past the asteroid at 15 km/s completing the flyby in just a minute. But the cameras and other instruments had been working for hours and in some cases days beforehand, and will continue afterwards. Shortly after closest approach, Rosetta began transmitting data to Earth for processing.
 

The new images and the data from Rosetta’s other instruments will help to decide but not tonight. Compositional information is needed for that.
 
Sensors investigate Lutetia
 
Rosetta operated a full suite of sensors at the encounter, including remote sensing and in-situ measurements. Some of the payload of its Philae lander were also switched on. Together they looked for evidence of a highly tenuous atmosphere, magnetic effects, and studied the surface composition as well as the asteroid’s density.
 
 

	Lutetia asteroid

The flyby marks the attainment of one of Rosetta’s main scientific objectives. The spacecraft will now continue to a 2014 rendezvous with its primary target, comet Churyumov-Gerasimenko. It will then accompany the comet for months, from near the orbit of Jupiter down to its closest approach to the Sun. In November 2014, Rosetta will release Philae to land on the comet nucleus.
 
 

July 9, 2010:  It's every vacationer's dream: You stretch out on a white sandy beach for a luxurious nap under the South Pacific sun. The caw of distant gulls wafts across the warm sea breeze while palm fronds rustle gently overhead. You take it all in through half-closed eyes.

Could Paradise get any better? This weekend it will.

On Sunday, July 11th, the new Moon will pass directly in front of the sun, producing a total eclipse over the South Pacific. The path of totality stretches across more than a thousand miles of ocean, making landfall in the Cook Islands, Easter Island, a number of French Polynesian atolls, and the southern tip of South America: map, timetables.

Shooting from the Cook Islands, astrophotographer Alan Dyer recorded this South Pacific eclipse on July 22, 2009. [larger image]

"It's going to be a beautiful sight," says Lika Guhathakurta of NASA's Heliophysics Division in Washington DC. She herself has witnessed more than eight solar eclipses in a variety of environments from busy cities to lonely deserts to remote mountain peaks. "The South Pacific eclipse could top them all."

As seen from space station Mir, the Moon's shadow sweeps across Earth during an eclipse in 1999. [more]

She imagines how the event will unfold: First, the Moon's cool shadow will sweep across the landscape, bringing a breeze of its own to compete with the sea's. Attentive observers might notice shadow bands (a well-known but mysterious corrugation of the Moon's outermost shadow) rippling across the beach as the temperature and direction of the wind shift. The ensuing darkness will have an alien quality, not as black as genuine night, but dark enough to convince seabirds to fly to their island roosts. As their cries subside, the sounds of night creatures come to the fore, a noontime symphony of crickets and frogs.

Next comes the moment that obsesses eclipse chasers: The corona pops into view. When the Moon is dead-center in front of the sun, mesmerizing tendrils of gas spread across the sky. It is the sun's outer atmosphere on full display to the human eye.

"You can only see this while you are standing inside the shadow of the Moon," says Guhathakurta. "It is a rare and special experience."

Because the sun's atmosphere is constantly shape-shifting, every total eclipse is unique. Predicting what any given one will look like can be tricky.

The sun's corona shows itself during the total solar eclipse of March 29, 2006. Credit: Koen van Gorp. [more]

Explanation: Most photographs don't adequately portray the magnificence of the Sun's corona. Seeing the corona first-hand during a total solar eclipse is best. The human eye can adapt to see features and extent that photographic film usually cannot. Welcome, however, to the digital age. The above picture is a combination of thirty-three photographs that were digitally processed to highlight faint features of a total eclipse that occurred in March of 2006. The images of the Sun's corona were digitally altered to enhance dim, outlying waves and filaments. Shadow seekers need not fret, though, since as yet there is no way that digital image processing can mimic the fun involved in experiencing a total solar eclipse. Last week, a spectacular total solar eclipse occurred over southern Asia, while the The next total solar eclipse will be visible from the South Pacific on 2010 July 11.

Nevertheless, Guhathakurta is making a prediction. It's based on a new development in solar physics. For the first time, NASA has two spacecraft stationed on opposite sides of the sun. "STEREO-A and STEREO-B are giving us a realtime 3D view of the solar corona, something we've never had before," she explains. "This helps forecast the appearance of the corona during an eclipse."

Inspecting images from STEREO and also from the Solar and Heliospheric Observatory (SOHO), she predicts observers could see four ghostly-white streamers, two on either side of the sun. They will stretch out two to three degrees, forming a gossamer "X" in the sky with a black hole at the crossing point.

"I'm prepared to be wrong," she confesses. "This is the first time anyone has tried to make such a forecast using STEREO data. It will be interesting to see if it works."

Check NASA's eclipse home page for more information about the July 11th eclipse, and stay tuned to Science@NASA, post-eclipse, for images from the path of totality.

SOLAR BLAST: Magnetic fields overlying sunspot 1087 became unstable and erupted yesterday. The explosion emitted a bright flash of UV light (a C3-class solar flare) and hurled a massive plume of hot plasma away from the sun. Click on the image to watch the action unfold:

movie formats: 2 MB mpeg; 1 MB iPad; 0.7 MB iPhone

NASA's Solar Dynamics Observatory (SDO) recorded the 1.5-hour time-lapse movie beginning at 1950 UT on July 9th. SDO has been busy since sunspot 1087 materialized, recording B- and C-class flares every few hours. So far none of the eruptions has been Earth-directed, but this could change in the days ahead as the active region turns to face our planet. Stay tuned for space weather.

more images: from Cai-Uso Wohler of Bispingen, Germany; from Jan Timmermans of Valkenswaard, The Netherlands; from Didier Favre of Brétigny-sur-Orge, France; from Peter Desypris of Syros, Greece; from Andreas Murner of Rosenheim, Bavaria, Germany

A solar wind stream flowing
 from the indicated coronal
hole should hit Earth's
magnetic field on or about
July 13th. Credit: SDO/AIA

SOUTH PACIFIC ECLIPSE: Yearning to visit the South Pacific? Now is the time to set sail. On July 11th, the Moon will pass directly in front off the sun, producing a total solar eclipse. The path of totality stretches across the south Pacific Ocean, making landfall in only a few places: Mangaia in the Cook Islands, Easter Island, and the southern tip of South America. Get the details from NASA.

Total Solar Eclipse of July 11

The second solar eclipse of 2010 occurs at the Moon's descending node in central Gemini just 45 arc-minutes east of the 3rd magnitude star Delta Geminorum. The path of the Moon's umbral shadow crosses the South Pacific Ocean where it makes no landfall except for Mangaia (Cook Islands), Easter Island (Isla de Pascua) and several isolated atolls. The path of totality ends just after reaching southern Chile and Argentina (Espenak and Anderson, 2008). The Moon's penumbral shadow produces a partial eclipse visible from a much larger region covering the South Pacific and southern South America (Figure 3).

The central eclipse path begins in the South Pacific about 700 km southeast of Tonga at 18:15 UT. Traveling northeast, the track misses Rarotonga - the largest and most populous of the Cook Islands - by just 25 km. The first landfall occurs at Mangaia where the total eclipse lasts 3 minutes 18 seconds with the Sun 14° above the horizon.

The southern coast line of French Polynesia's Tahiti lies a tantalizing 20 km north of the eclipse path and experiences a deep 0.996 magnitude partial eclipse at 18:28 UT. Several cruises are already scheduled to intercept the umbral shadow from Papeete.

Greatest eclipse occurs in the South Pacific at 19:33:31 UT. At this instant, the axis of the Moon's shadow passes closest to Earth's center. The maximum duration of totality is 5 minutes 20 seconds, the Sun's altitude is 47°, and the path width is 259 km. Continuing across the vast Pacific, the umbral shadow's path encounters Easter Island, one of the most remote locations on Earth. From the capital, Hanga Roa, totality lasts 4 minutes 41 seconds with the Sun 40° above the horizon (20:11 UT). The 3,800 inhabitants of the isle are accustomed to tourism, but the eclipse is expected to bring record numbers to this unique destination.

The Moon's shadow sweeps across another 3700 km of open ocean before beginning its final landfall along the rocky shores of southern Chile at 20:49 UT. The shadow is now an elongated ellipse and its increasing ground velocity brings with it a corresponding decrease in the duration of totality. It is mid-winter in the Andes so clouds and high mountain peaks threaten to block views of the total eclipse. Nevertheless some hearty eclipse observers will find Argentina's tourist village of El Calafate a prime destination for the eclipse. The Sun's altitude is only 1° during the 2 minute 47 second total phase, but the lake may offer an adequate line-of-site to the eclipse hanging just above the rugged Andes skyline.

The path ends in southern Argentina when the umbra slips off Earth's surface as it returns to space (20:52 UT). Over the course of 2 2/3 hours, the umbra travels along a track approximately 11,100 km long that covers 0.48% of Earth's surface area. It will be 29 months before the next total solar eclipse occurs on 2012 Nov 13.

Path coordinates and central line circumstances are presented in Table 4. Local circumstances for a number of cities are listed in Table 5. All times are given in Universal Time. The Sun's altitude and azimuth, the eclipse magnitude and obscuration are all given at the instant of maximum eclipse.

This is the 27th eclipse of Saros 146 (Espenak and Meeus, 2006). The series began on 1541 Sep 19 with the first of an unusually long series of 22 partial eclipses. The first central eclipse was total with a maximum duration of 4.1 minutes on 1938 May 29. Subsequent total eclipses in the series have seen an increase in the duration of totality. The 2010 eclipse marks the longest totality of Saros 146 because future durations will decrease. The series produces the first of 4 hybrid eclipses on 2172 Oct 17. The remaining 24 central eclipses of Saros 141 are all annular and span the period from 2244 Dec 01 to 2659 Aug 10. The series ends with a set of 13 partial eclipses the last of which occurs on 2893 Dec 29.

In all, Saros 146 produces 35 partial, 13 total, 4 hybrid and 24 annular eclipses. Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/SEsaros/SEsaros146.html

Complete details including many tables, maps and weather prospects can be found in the NASA 2010 eclipse bulletin (Espenak and Anderson, 2008) and online at:

eclipse.gsfc.nasa.gov/SEmono/TSE2010/TSE2010.html

Finally, a web-based zoomable map of the 2010 total eclipse path is available plotted on Google maps at:

eclipse.gsfc.nasa.gov/SEgoogle/SEgoogle2001/SE2010Jul11Tgoogle.html

Total Lunar Eclipse of December 21

The last lunar eclipse of 2010 is especially well placed for observers throughout North America. The eclipse occurs at the Moon's descending node in eastern Taurus, four days before perigee.

The Moon's orbital trajectory takes it through the northern half of Earth's umbral shadow. Although the eclipse is not central, the total phase still lasts 72 minutes. The Moon's path through Earth's shadows as well as a map illustrating worldwide visibility of the event are shown in Figure 4. The timings of the major eclipse phases are listed below.

Penumbral Eclipse Begins:   05:29:17 UT
Partial Eclipse Begins:     06:32:37 UT
Total Eclipse Begins:       07:40:47 UT
Greatest Eclipse:           08:16:57 UT
Total Eclipse Ends:         08:53:08 UT
Partial Eclipse Ends:       10:01:20 UT
Penumbral Eclipse Ends:     11:04:31 UT

At the instant of greatest eclipse (08:17 UT) the Moon lies near the zenith for observers in southern California and Baja Mexico. At this time, the umbral magnitude peaks at 1.2561 as the Moon's southern limb passes 2.8 arc-minutes north of the shadow's central axis. In contrast, the Moon's northern limb lies 8.1 arc-minutes from the northern edge of the umbra and 34.6 arc-minutes from the shadow center. Thus, the southern half of the Moon will appear much darker than the northern half because it lies deeper in the umbra. Since the Moon samples a large range of umbral depths during totality, its appearance will change dramatically with time. It is not possible to predict the exact brightness distribution in the umbra, so observers are encouraged to estimate the Danjon value at different times during totality (see Danjon Scale of Lunar Eclipse Brightness). Note that it may also be necessary to assign different Danjon values to different portions of the Moon (i.e., north vs. south).

During totality, the winter constellations are well placed for viewing so a number of bright stars can be used for magnitude comparisons. Pollux (mv = +1.16) is 25° east of the eclipsed Moon, while Betelgeuse (mv = +0.45) is 16° to the south, Aldebaran (mv = +0.87) is 20° to the west, and Capella (mv = +0.08) is 24° to the north.

The entire event is visible from North America and western South America. Observers along South America's east coast miss the late stages of the eclipse because they occur after moonset. Likewise much of Europe and Africa experience moonset while the eclipse is in progress. Only northern Scandinavians can catch the entire event from Europe. For observers in eastern Asia the Moon rises in eclipse. None of the eclipse is visible from south and east Africa, the Middle East or South Asia.

Table 6 lists predicted umbral immersion and emersion times for 20 well-defined lunar craters. The timing of craters is useful in determining the atmospheric enlargement of Earth's shadow (see Crater Timings During Lunar Eclipses).

The December 21 total lunar eclipse belongs to Saros 125 a series of 72 eclipses in the following sequence: 17 penumbral, 13 partial, 26 total, 9 partial, and 7 penumbral lunar eclipses (Espenak and Meeus, 2009). Complete details for the series can be found at:

eclipse.gsfc.nasa.gov/LEsaros/LEsaros125.html

Solar Eclipse Figures

Lunar Eclipse Figures

Shadow Diameters and Lunar Eclipses

Danjon Scale of Lunar Eclipse Brightness

Crater Timings During Lunar Eclipses

Eclipse Altitudes and Azimuths

The altitude a and azimuth A of the Sun or Moon during an eclipse depend on the time and the observer's geographic coordinates. They are calculated as follows:

h = 15 (GST + UT - α ) + λ
a = arcsin [sin δ sin φ + cos δ cos h cos φ]
A = arctan [-(cos δ sin h)/(sin δ cos φ - cos δ cos h sin φ)]

where

h = hour angle of Sun or Moon
a = altitude
A = azimuth
GST = Greenwich Sidereal Time at 0:00 UT
UT = Universal Time
α = right ascension of Sun or Moon
δ = declination of Sun or Moon
λ = observer's longitude (east +, west -)
φ = observer's latitude (north +, south -)

During the eclipses of 2010, the values for GST and the geocentric Right Ascension and Declination of the Sun or the Moon (at greatest eclipse) are as follows:

Eclipse             Date          GST         α         δ

Annular Solar    2010 Jan 15     7.642      19.797    -21.127
Partial Lunar    2010 Jun 26    18.299      18.353    -24.002
Total Solar      2010 Jul 11    19.307       7.399     22.036
Total Lunar      2010 Dec 21     5.986       5.955     23.746

Two web based tools that can also be used to calculate the local circumstances for all solar and lunar eclipses visible from any location. They are the Javascript Solar Eclipse Explorer and the Javascript Lunar Eclipse Explorer. The URLs for these tools are:

Javascript Solar Eclipse Explorer: eclipse.gsfc.nasa.gov/JSEX/JSEX-index.html

Javascript Lunar Eclipse Explorer: eclipse.gsfc.nasa.gov/JLEX/JLEX-index.html

Eclipses During 2011

During 2011, there will be four partial solar eclipses and two total lunar eclipses:

• 2011 Jan 04: Partial Solar Eclipse
• 2011 Jun 01: Partial Solar Eclipse
• 2011 Jun 15: Total Lunar Eclipse
• 2011 Jul 01: Partial Solar Eclipse
• 2011 Nov 25: Partial Solar Eclipse
• 2011 Dec 10: Total Lunar Eclipse

A full report on eclipses during 2011 will be published in Observer's Handbook 2011.

NASA Solar Eclipse Bulletins

Special bulletins containing detailed predictions and meteorological data for future solar eclipses of interest are prepared by Fred Espenak and Jay Anderson and are published through NASA's Publication series. The bulletins are provided as a public service to both the professional and lay communities, including educators and the media. A list of currently available bulletins and an order form can be found at:

eclipse.gsfc.nasa.gov/SEpubs/RPrequest.html

The most recent bulletin of the series covers the annular and total solar eclipses of 2010. Single copies of the eclipse bulletins are available at no cost by sending a 9 x 12-in. self-addressed envelope stamped with postage for 11 oz. (310 g). Please print the eclipse year on the envelope's lower left corner. Use stamps only, since cash and cheques cannot be accepted. Requests from outside the United States and Canada may include 10 international postal coupons. Mail requests to: Fred Espenak, NASA's Goddard Space Flight Center, Code 693, Greenbelt MD 20771, USA.

The NASA eclipse bulletins are also available over the Internet, including out-of-print bulletins. They can be read or downloaded from the NASA Eclipse Web Site at:

eclipse.gsfc.nasa.gov/SEpubs/bulletin.html

Eclipse Web Sites

The URL of the NASA Eclipse Web Site is:

eclipse.gsfc.nasa.gov/eclipse.html

The site features predictions and maps for all solar and lunar eclipses well into the 21st century, with special emphasis on upcoming eclipses. Special pages are devoted to the total solar eclipses of 2008, 2009 and 2010 that feature detailed maps, tables, graphs, and meteorological data. A world atlas of solar eclipses provides maps of all central eclipse paths from 2000 BCE to 3000 CE. The entire Five Millenium Canon of Solar Eclipses [Espenak and Meeus, 2006] can be downloaded in PDF format and all maps are also available online as individual GIFs of PSFs. Additional catalogues list every solar and lunar eclipse over a 5000-year period.

Detailed information on solar and lunar eclipse photography and tips on eclipse observing and eye safety may be found at:

www.mreclipse.com

Acknowledgments

All eclipse predictions were generated on an Apple G4 iMac computer using algorithms developed from the Explanatory Supplement [1974] with additional algorithms from Meeus, Grosjean, and Vanderleen [1966]. The solar coordinates used in the eclipse predictions are based on VSOP87 [P. Bretagnon and G. Francou, 1988]. The lunar coordinates are based on ELP-2000/82 [M. Chapront-Touzé and J. Chapront, 1983]. For lunar eclipses, the diameter of the umbral and penumbral shadows were calculated using Danjon's rule of enlarging Earth's radius by 1/85 to compensate for the opacity of the terrestrial atmosphere; corrections for the effects of oblateness have also been included. Text and table composition was done on a Macintosh using Microsoft Word. Additional figure annotation was performed with Claris MacDraw Pro.

All calculations, diagrams, tables, and opinions presented in this paper are those of the author, and he assumes full responsibility for their accuracy.

Footnotes

[1] The instant of greatest eclipse occurs when the distance between the Moon's shadow axis and Earth's geocenter reaches a minimum.

[2] Eclipse magnitude is defined as the fraction of the Sun's diameter occulted by the Moon

[3] The sub-solar point is the geographic location where the Sun appears directly overhead (zenith).

References

Bretagnon P., Francou G., "Planetary Theories in rectangular and spherical variables: VSOP87 solution", Astron. and Astrophys., vol. 202, no. 309 (1988).

Chapront-Touzé, M and Chapront, J., "The Lunar Ephemeris ELP 2000," Astron. and Astrophys., vol. 124, no. 1, pp 50-62 (1983).

Chauvenet, W., Manual of Spherical and Practical Astronomy, Vol.1, 1891 (Dover edition 1961).

Danjon, A., "Les éclipses de Lune par la pénombre en 1951," L'Astronomie, 65, 51-53 (Feb. 1951).

Espenak, F., Fifty Year Canon of Solar Eclipses: 1986–2035, Sky Publishing Corp., Cambridge, MA, 1988.

Espenak, F., Fifty Year Canon of Lunar Eclipses: 1986–2035, Sky Publishing Corp., Cambridge, MA, 1989.

Espenak, F., and Anderson, J., Annular and Total Solar Eclipses of 2010, NASA TP–2008-214171, Goddard Space Flight Center, Greenbelt, MD, 2008.–

Espenak, F., and Meeus, J., Five Millennium Canon of Solar Eclipses: –2000 to +3000 (2000 BCE to 3000 CE), NASA TP–2006-214141, Goddard Space Flight Center, Greenbelt, MD, 2006.

Espenak, F., and Meeus, J., Five Millennium Canon of Lunar Eclipses: –2000 to +3000 (2000 BCE to 3000 CE), NASA TP–2009-214172, Goddard Space Flight Center, Greenbelt, MD, 2006.

Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac, Her Majesty's Nautical Almanac Office, London, 1974.

Littmann, M., Espenak, F., & Willcox, K., Totality—Eclipses of the Sun, 3rd Ed., Oxford University Press, New York, 2008.

Meeus, J., Grosjean, C.C., & Vanderleen, W., Canon of Solar Eclipses, Pergamon Press, New York, 1966.

Meeus, J. & Mucke, H., Canon of Lunar Eclipses: -2002 to +2526, Astronomisches Buro, Wien, 1979.

A SUNSPOT APPROACHES: For several days, NASA's STEREO-B spacecraft has been monitoring an apparent sunspot on the far side of the sun. Just yesterday, it erupted and hurled a bright coronal mass ejection over the edge of the solar disk (movie). Now, the sunspot itself is approaching:

The Solar and Dynamics Observatory took this extreme ultraviolet picture just hours ago. It shows the spot's magnetic canopy towering over the sun's eastern limb, heralding the appearance of the sunspot's core on July 9th or 10th. After that the active region will turn to face Earth and any further eruptions could be geo-effective. Stay tuned for space weather.

FARSIDE BLAST: Old sunspot 1082, currently rounding the far side of the sun, erupted during the late hours of July 5th. The Solar and Heliospheric Observatory recorded a CME billowing over the edge of the solar disk (movie) while NASA's STEREO-B spacecraft had a direct view of the explosion itself (movie). The farside location of the blast site means there will be no Earth effects from the event--not this time. The active region will turn to face Earth after July 10th. Stay tuned.

UPDATE: A Solar Dynamics Observatory movie of the farside blast billowing over the sun's limb is now available.

4TH OF JULY FIREWORKS: It has been a busy weekend on the sun. So far the Solar and Heliospheric Observatory (SOHO) has recorded no fewer than five CMEs blasting out of the sun's atmosphere. Click on the image to set the clouds in motion:

The two brightest CMEs, pictured above, were caused by eruptions of unrelated magnetic filaments on opposite sides of the sun. The origin of the other three CMEs in the movie remains uncertain. None of the clouds appears to be heading toward Earth; the display was photogenic, but not geoeffective.

Stay tuned for follow-up movies from the Solar Dynamics Observatory, which should reveal some of the blast sites in greater detail.

PINWHEEL SUNSPOT: The dark core of sunspot 1084 is twice as wide as Earth itself. More impressive, however, is the enormous swirl of hot gas and magnetic fields suspended overhead. Today's extreme UV image from NASA's Solar Dynamics Observatory reveals the sunspot's pinwheel canopy:

This magnetic architecture must be stable, because sunspot 1084 is remarkably quiet. There hasn't been the slightest hint of a flare from this "active" region for the past two days. It is, however, photogenic. Readers with solar telescopes are encouraged to take a look.

more images: from Rogerio Marcon of Campinas SP Brasil; from Jo Dahlmans of the Netherlands; from Roy McCullough of Youngstown, Ohio; from Peter Desypris of Island of Syros, Greece;