Lunar Eclipse Maestro

Are you contemplating serious photography of the lunar eclipse on the morning of October 8th?

If you have an Apple MacBook computer and any standard DSLR, an excellent app enables automated photography with speed and aperture settings automatically adjusted for the changing light conditions during the total lunar eclipse. This app is developed by my friend and fellow eclipse chaser, Xavier Jubier. Xavier has also kindly provided me with a computation engine that I use to create most of my eclipse maps.

From Xavier's description:

"Lunar Eclipse Maestro 1.3.1, the most versatile and feature-rich application for lunar eclipses, is now available for download. Two versions are available: one is a Universal Binary running on Tiger or newer and the other, Intel only, running on Snow Leopard and newer.

Both versions support all the Nikon DSLRs including the latest D4s, D810 and D750. However the latest Canon cameras (EOS 1200D/Rebel T5/Kiss X70, 100D/Rebel SL1/Kiss X7, 600D/Rebel T3i/Kiss X5, 650D/Rebel T4i/Kiss X6i, 700D/Rebel T5i/Kiss X7i, 70D, 7D Mark II, 6D, 5D Mark III, 1D X and 1D C) are only supported on the Intel version. Legacy Canon cameras (EOS 350D/Rebel XT/Kiss N, 20D/20Da and 5D) are only supported by the Universal Binary version. All the SBIG CCD cameras and their filter wheels are now supported as well and it does also work with a few Nikon Coolpix cameras.

Users of all the previous releases are strongly encouraged to upgrade to this version as it brings improvements and fixes bugs (mainly regressions). That way you will be able to enjoy new or improved features and bug fixes as well as eclipses even more without worrying about operating your digital cameras.

Many under the hood improvements were made and one interesting feature was improved for Nikon DSLRs: shooting at full resolution with the mirror always raised is now possible (shouldn't be confused with video mode). This will give even better results and reduce the time needed between successive frames as you don't need to wait after locking-up the mirror.

To know more and download please visit:

And direct comments, questions, or problems to me on the support board:

To post you will need to register first, but you'll also benefit from the experience of others to find answers to your questions or problems. Please try to post in English in order to have a larger audience. I will generally answer in English to messages in French, Italian, German or Spanish, unless you clearly specify otherwise.

Clear skies,


Introduction to lunar eclipse photography

by Bill Kramer, IAU WGSE,

Total lunar eclipse of February 21, 2008 photographed with a 400 mm lens

Total lunar eclipse of February 21, 2008 photographed with a 400 mm lens

Photographing a lunar eclipse, such as the one coming up on the 8th of October, is pretty easy if you have some basic photography equipment beyond a cell phone. Cell phone cameras are great at capturing people and scenery, but they do not have a good lens for longer focal length photography, and good lunar eclipse photography requires some focal length.

The good news is that you do not have to have a professional camera either. All you need is a camera with at least a focal length of 100mm (effective) and really no more than 1000mm. The longer the focal length, the better the mount you will require. For the 100mm variant a basic tripod will do the trick. As you get into the longer lengths a sturdier choice is best and as you go above 400mm the mount will need to track the movements of the Moon for longer exposures. For more details about mounting a camera for astrophotography, please visit

The camera settings need to be more than automatic. You will want to use manual settings for the lunar eclipse photography. The exposures needed to capture different aspects of the eclipse vary based on the focal ratio (or f/stop) and just what it is you are after. During totality much longer exposures are needed to catch the red brown color. Even longer exposures will turn the eclipsed Moon orange and expose stars in the background. Of course, the longer the exposure, the better the mount must be.

Here is a simple tip. Use the 10 second delay setting on the camera. Typically this setting is used when you use a tripod and you want to be in the picture. The ten seconds give you time to get from the camera to  where you want to be in the resulting picture. When taking an image of totality with a modest camera of 100mm, set up an exposure of say 5 – 10 seconds. Next set the delayed image. Press the start and let the camera settle down on the tripod before taking the picture. The mount needs to be steady and not subject to a lot of vibration or swaying in the wind. Using this technique you can get great images of the eclipse and near by bright stars.

The image size is something to be considered for really striking lunar eclipse pictures. The longer the focal length, the more detail you can see in the lunar surface features. On the other side of the equation, the less focal length you use, the more scenery that can be incorporated. And during the total phase of the lunar eclipse, you can take a longer exposure to help capture that scenery under the eerie light of the lunar eclipse. Under 100mm the image of the eclipsed moon becomes an orange-brown dot in the final image. Enlarging it will not bring in much detail. However a landscape image that has lots of contrast could be very interesting in the light of a full lunar eclipse.

For more details related to lunar eclipse photography, please refer to

TSE2017 & education in the U.S.

Michael mentioned in the postscript to my first blog entry that I am a science teacher on sabbatical this school year, dedicated to generating awareness and knowledge of the 2017 eclipse. This is true, but as I visit different school districts, I am realizing that there is so much more to be addressed: I also need to assess and learn how students, teachers, administrators, parents and even local governments and communities can work together to improve the state of education in the U.S.

Being a professional educator for almost 20 years (and a student before that), I have seen the curriculum pendulum make many arcs, never staying in place too long because there is always something “better” on the way, at least in the minds of education departments, state governors and in Washington. And with each new paradigm shift (as they say in education) comes its own jargon, buzzwords, and learning strategies that are presumed to be superior to what came before. “No Child Left Behind,” “IDEA ’97,” “STEM,” and “Common Core” are but a few of the terms to describe our nation’s continuing urge to find the best way for teachers to teach and for students to learn.

But what I’m finding instead is growing frustration among all parties involved--teachers are confused about what is required of them; our students are performing poorly compared to other countries; administrators are coming down hard on teachers; parents are angry at the entire system; and the government thinks this can all be remedied with new and different learning straegies and increased teacher accountability.

The fundamental problem I’m encountering is a lack of foundation of the basics among both students and teachers. And by “basics,” I really mean just that: Where does the sun go when it sets? Why do the Sun, Moon and stars seem to move across the sky? Why does the Moon change shape every day? Why do we sometimes see the Moon during the day and sometimes not at night? What causes solar and lunar eclipses? And that’s just astronomy--now apply that across all content areas, and you begin to see what we are up against.

Yet, ironically, much of the public does want to learn more about science. I see it all the time when I host outdoor astronomy sessions with a telescope. The oohs and aahs and questions last all evening, and many times, it’s the adults who are most intrigued and astonished by what they’re looking at, more so than the students, and I have an idea why (but that’s for another entry).

Another irony: the seeming paradox of having the most information available to us, at any hour of the day, delivered virtually instantaneously to our eyes, yet we seemingly know less about the outside world and its workings than our forebears did at the turn of the last century. I have been reading the wonderful publications found on this site from this and other centuries’ authors, and what a great working knowledge they had of the celestial mechanics involved with the occurrences and predictions of eclipses. And the writing! Descriptive and flowing and so much better than anything anyone is writing today about eclipses. I got chills reading James Fenimore Cooper’s account of the 1806 total eclipse that he and his fellow villagers observed together.

It is my hope that the schools I visit this year want to learn more about what will happen less than three years from now, even though TSE 2017 will most likely not be a specific addition to their curricula. And it is also my hope that these same schools will allow their students to watch it where they should be watching it from: outside of the classroom.

Eclipses in Science Fiction

Partial eclipse over the Vehicle Assembly Building at the Kennedy Space Center. Copyright David Dickinson, November 3, 2013

Ever wonder about the eclipses that you won’t see? Life is short, and the span of eclipse cycles is long. Often, the only way to experience these”eclipses of the mind” that occurred in the far past, the distant future, or from the surface of another world is to use our imagination. 

Eclipses — especially total solar eclipses — do crop up in culture and fantasy/science fiction from time to time, with varying degrees of accuracy.  An eclipse marked the “day without a night and the night without a day” in the film Ladyhawke. An eclipse also turned up — impossibly, falling on the same day as a Full Moon (!) — in Mel Gibson’s Apocalypto. A total solar eclipse was even actually filmed live for the 1961 movie Barabbas, though with the historical crucifixion occurring near Passover, you’d think a total lunar eclipse would be a better fit. Strangely, annular and total lunar eclipses are nearly absent in fiction and movies… apparently, Hollywood is only interested in “killer asteroids bigger than Texas,” and always goes for the gusto with the top billed celestial event: a total solar eclipse.    

We recently hatched some fictional ideas for stories that involve eclipses ourselves. As is often the case with the creative process, what started out as one story idea swiftly grew into about half a dozen and an idea for a short story anthology.  Our first published tale, Exeligmos, covers a key question that is in the mind’s eye of many an eclipse chaser: what eclipse would you travel through time and space to see, if you could? The title Exeligmos refers the name of the 54-plus year triple saros series of eclipses and the protagonist’s floundering travel agency. But when cutting edge tech gives him the ability to fulfill his obsession, there’s no eclipse in time and space out of his grasp. What’ll it be? The first annular eclipse in the distant Neoproterozoic era 900 million years ago, or the final total solar eclipse 14 millions of years hence?    

The second story of the series, Shadowfall, takes place on a distant fictional world. It will, of course, draw inevitable comparisons to The Hunger Games, though we had Stephen King’s story The Long Walk in mind when we wrote it. The story itself arose from a recent thought experiment: with the Moon slowly receding from the Earth, would there be a time in the very distant future when one could follow the umbra during an eclipse on foot? Such a feat would certainly give a new and literal dimension to the term “eclipse chasing…” After some discussion and rough calculations, it seemed better to locate such an event on a fictional exoplanet, complete with a large moon in a retrograde orbit. Hey, in science fiction, we can always brew up a world fit to order straight from the imagination!  

What’s next? Well, what might eclipse tourism look like from an alien perspective? Might an eclipse play a role in a future surprise assault on an imperial Earth? And could the penultimate eclipse far off in time play a role in a washed out metal band’s comeback?

Watch for these tales and more over the coming months, as well as the real world total lunar eclipse of October 8th and the partial solar eclipse of October 23rd, both visible from North America.   

The total solar eclipse of August 21st, 2017 promises to bring a new awareness of this fascinating phenomenon to millions, and will doubtless spawn a new generation of world-spanning eclipse chasers bitten by the bug. Sure, you might not be able to journey through time or to other worlds to spy exotic eclipses, but you can make plans now — as many small towns across the United States are already doing — to witness the next total solar eclipse to grace the contiguous U.S.

Where will you be in 2017?  

Exeligmos on Amazon 

Shadowfall on Amazon 

Eclipse viewers of yore

An essential piece of gear while watching eclipses are eclipse glasses or, eclipse viewers. Solar eclipses are such memorable events in one's life that eclipse viewers are often saved over the decades and generations. A collection of these historic viewers is now on display at Williams College, Massachussetts. Following is a description of this collection by Professor Jay Pasachoff:

A total solar eclipse is safe to view directly during totality, when the Moon completely covers the Sun and only the corona is visible.  However, before and after totality or during partial or annular phases of the eclipse, the visible sun is almost a million times brighter than the corona; eye protection is necessary for safe viewing of the eclipse.  Luke Cole (1962-2009) amassed a collection of eclipse viewers–special glasses with filters specifically for viewing the eclipsed Sun–from eclipses since 1793.  Viewers starting with the eclipse of 1831 are on display here. 

See for a full display.

The collection was donated by Nancy Shelby of San Francisco, CA in memory of her late husband, Luke Cole, who collected the eclipse viewers.  The liaison with Williams College’s Hopkins Observatory was arranged by Skip Cole, Williams College class of 1957.

The total solar eclipse of August 21, 2017, will be visible as partial from the whole Continental United States, so viewers like these will be in general circulation.  The path of totality will cross from Oregon to South Carolina, and even within the path, viewers like these will be needed before and after totality during the partial phases.

A selection of the actual viewers is on physical display in Williams College, Massachusetts. our Mehlin Museum of Astronomy, which is part of our Hopkins Observatory, the oldest extant astronomical observatory in the U.S.:

You gotta see totality!

My friend holding her eclipse shades to see the setting sun about halfway eclipsed during the 2010 TSE in El Calafate, Patagonia, Argentina

My friend holding her eclipse shades to see the setting sun about halfway eclipsed during the 2010 TSE in El Calafate, Patagonia, Argentina

I'm Charles Fulco--science teacher, planetarium director and "eclipse chaser" (more properly known as an "umbraphile"). As a kid, my first contact with an eclipse was a good one, a near miss at 96% over my hometown of Port Chester, NY in March 1970. It was enough to make the sky noticeably dim, but unfortunately not totally dark. 

Had I known then what I know now, I would have done whatever it took to convince my mother to drive us to Virginia to witness the eclipse in its totality. But, no, instead I watched it on our living room TV. My mother, like every other parent in the country, listened to Bill Cosby and other celebrities who told everyone, via public service announcements, to stay inside and watch the eclipse on television. I remember feeling cheated afterward. And I realize now that I was—we all were. Warnings by school officials, teachers, and even comedians (!) about "eclipse rays” given off by the Sun and cautionary tales of people going blind just by being outside meant we all missed the opportunity to see one of the most amazing phenomena imaginable. "Stay inside and close the blinds!" they warned. So of course we did. They didn’t know there was a safe way to view this incredible event.

It was another 21 long years before I had another chance to see a total eclipse, and it also happened to be the longest totality until 2132, so I was extra fortunate. I watched the “Big One” live from a beach near Mazatlan, Mexico. To this day, I believe it was the most magnificent and eerie and miraculous thing I have ever experienced. Since that eclipse, I've been lucky enough to be under the Moon's shadow three more times (on three different continents). Each was beautiful and each was different.

Anyone who has seen a total solar eclipse knows there is no comparison between watching an eclipse on television and seeing one live with your own eyes. On August 21, 2017, we will have an opportunity in the US to view another total solar eclipse, this one beginning in Oregon and cutting a path across the country to South Carolina. Most of the population of the United States is within a day’s drive to the path of totality.  And this is why a group of concerned scientists and educators have begun a program of outreach to dispel myths, correct "bad science," promote safe observing methods, and mostly tell everyone to "get your ass to totality!" You’ll be hearing a lot from us in the next 2 years and 11 months.

Close up of the sunset total solar eclipse over Patagonia

Michael Zeiler has generously let me have this space on his Great American Eclipse website to talk about education and the eclipse. I look forward to sharing ideas, lesson plans and everything else that teachers, students, school officials, and entire communities can do to prepare for this nationwide event. Thanks for stopping by!

Editor's note: This is the first of a series of contributions by Charles. He is a teacher on a sabbatical dedicated to developing educational plans to inspire young people to see the total solar eclipse of 2017. If you have stories to share or ideas for education, leave them in the comments section below.

Mystery of the Ansel Adams eclipse photo

Today, I found an interesting photograph of a solar eclipse attributed to Ansel Adams. You can find this image at This photograph is labelled with possible dates from 1923 to 1925 and is said to have been photographed from a place called Cantonville, California. 

There are two issues with this identification: 

  1. The only central solar eclipse in this time span that visited California was the 1923 total solar eclipse which grazed the southwestern coast. But the photograph clearly shows what is known as a 'broken annular' eclipse in which the Moon very nearly occults the Sun but a string of Baily's Beads persists around the circumference. 
  2. There is no identifiable place in California called Cantonville. 

The photograph could not have been of the 1923 eclipse and Cantonville does not seem to exist. So where and when was this photograph taken? I posed this question to the Solar Eclipse Mailing List (SEML) and quickly received a plausible solution.

First, the eclipse is most probably the annular-total (hybrid) solar eclipse of April 28, 1930. The total phase of this eclipse was calculated to be exceedingly short, about 1 second. With totality this short, it is likely that the Sun's disk was never completely extinguished. That is, some bits of the Sun's photosphere were left uncovered by some of the lunar valleys in profile.

Second, the place name of 'Cantonville' is very probably a misspelling of Camptonville where an eclipse observing expedition was dispatched by the Lick Observatory that year. 

This video offers some confirmation of this. You will see that the skies were characterized by thin clouds and that the bead pattern in the video resembles the bead pattern in the photograph. The evidence of the similar bead pattern and the close resemblance of the place names 'Cantonville' and 'Camptonville' suggests strongly that this is the eclipse and the location of Ansel Adams' photograph.

Steve Allen of the Lick Observatory noted in a communication on SEML that perhaps Ansel Adams did not actually take this photograph, but made a photographic print from a plate from the Lick Observatory archive. He notes that Ansel Adams did some photographs of the Lick Observatory and it is plausible that he had access to the eclipse archive.

Update on August 29: In a subsequent email communication to SEML, Steve Allen notes that Ansel Adams was a neighbor of the brother of an astronomer on the expedition and opines that it is plausible that Ansel Adams took the plate as well as made the print. At present, there is no conclusive evidence of whether Adams or a Lick Observatory astronomer took the plate.

A further confirmation of the identity of the eclipse photographed by Ansel Adams is this simulation of the Baily's Beads computed for this time and place by Xavier Jubier, This is from his software app Solar Eclipse Maestro. The match is very good and there is no doubt that the correct eclipse has been identified.

Update on September 8:  I've made an inquiry to the Center for Creative Photography which holds this photograph. I asked for further evidence which can ascertain whether Ansel Adams took the photographic plate as well as making the print. I've received this reply from Leslie Squyres:

Dear Michael Zeiler,

Attached to this email are images of the verso of the photograph by Ansel Adams.  I contacted a scholar who worked closely with Adams.  Andrea Stillman wrote, “It's by Ansel. As I recall he was very proud of it.  I sent the verso images to her to verify the handwriting for me.  I know for certain that the date correction is Ansel Adams’s handwriting.  She remembers that somewhere Adams talks about making the photograph – I’m still trying to track down that reference and will get back to you. In a 1978 interview for the Bancroft Library Oral History project, Adams mentions that his father was treasurer of the Astronomical Society of the Pacific and that he and his father went to “Mt. Hamilton often.”

Adams was notoriously bad at recording dates.  If you know for absolute certainty that the photograph was taken in 1930, could you let me know? 

Best wishes,

Leslie Squyres

Director of the Volkerding Center for Research & Academic Programs

Center for Creative Photography, University of Arizona

No definitive answer yet on whether Ansel Adams indeed took the plate, but Leslie's message reveals new clues and some further leads. 

Below are details of the reverse side of the print.

The Minus-Third Anniversary of the 2017 US-Crossing Total Solar Eclipse

My friend Professor Jay Pasachoff recorded this blog post on the day that is exactly three years before the August 21, 2017 total solar eclipse. Jay is a leader in the solar eclipse community and has likely seen more solar eclipses than anyone else. His present count is 59, of which 31 are total solar eclipses, 15 are annular solar eclipses, and 13 are partial solar eclipses. He is the chair of the International Astronomical Union’s Working Group on Eclipses and is the Field Memorial Professor of Astronomy at Williams College. He has also written several books on solar physics and astronomy. 

Jay has a gift for expressing the beauty and science of a total solar eclipse in a way that anyone can understand. From the beginning of the podcast:

A total solar eclipse is the most inspiring thing, and beautiful thing, that anybody on Earth can see. The Sun going dark, being covered by the moon in the middle of the day, is awe-inspiring and even frightening, and has been so for thousands of years.  We in the United States are going to benefit from the band of totality of a total solar eclipse crossing the United States from upper left to lower right, from Northwest to Southeast on August 21, 2017.  I am making this podcast to mark the minus-third anniversary of this wonderful event.  

Listen to this podcast and be inspired: 


First impressions of the Thousand Year Canon of Solar Eclipses

These are my reactions to receiving this new canon.

I ordered this book immediately after I found it on Amazon last Sunday night. It arrived to me on Wednesday. Considering that this book was actually printed on demand to my order, that's a remarkable turn-around. Even though I missed out on the discount that Fred announced for attendees of the SEC2014, I'm still very glad to have this two months in advance.

The quality of the book is excellent. You cannot discern that it was printed on demand compared to traditional press run publishing.

The book begins with a 50 page section on eclipse fundamentals, the computational basis of the canon, frequency and distribution of eclipses, and a thorough explanation of the tabular columns in the canon and how to read the eclipse maps. Although I am reasonably well-versed on eclipse fundamentals, there is new explanatory content that I was not fully familiar with. For example, there is an interesting discussion of quincena combinations of eclipses that helps clarify the succession of eclipse types. This first section is tight and full of facts; much of this content is reminiscent of the Mathematical Morsels by Jean Meeus but this is not a regurgitation of the MM content; instead this is fresh analysis on the distribution and frequency of eclipses. These distributions are highlighted with a number of tables of eclipses within the thousand year range of this canon.

Pages 53 to 92 is a tabular listing of the essential characteristics of each of the 2,389 solar eclipses from 1501 to 2500; date, time, delta-t, series numbers, eclipse type, gamma, magnitude, lat-long of GE, sun azimuth and altitude at GE, path width, maximum duration, and an interesting characteristic I've never before seen in a canon: QLE.

QLE, or the Quincena Lunar Eclipse Parameter, describes the relationship of the pairings of lunar eclipses and solar eclipses. A short text string identifies whether a lunar eclipse precedes or occurs after the given solar eclipse, along with the type of lunar eclipse (penumbral, partial, or total).

Pages 95 to 294 comprise the bulk of the book and map each of the 2,389 eclipses. There are 12 maps on each page, but because the print quality is very good, they are very legible. There is a color code to the eclipse lines; green for sunset/sunrise lines and penumbral limits, blue for isomagnitudes of 0.25, 0.5, and 0.75, red for annular eclipse limits, and blue for total eclipse limits. I checked the central limit lines for hybrid eclipses and indeed, the cross-over point from annular to total is marked by a transition from blue to red, a very nice touch that is rarely visible on eclipse maps.

The most useful aspect of this book is how handy it is. I have several old canons on my bookshelf that I rarely consult. This new canon is compact and I've kept it within reach instead of filing it on my bookshelf. It's very convenient to pick up and look over historic and future eclipses.

The utility of this canon is like the old saying about telescopes: the best telescope is not necessarily the largest, but the one you use most. So it is with this canon.

The book can be ordered here:


I am pleased to launch on this day, exactly three years before the total solar eclipse of August 21, 2017. 

This website is just beginning. Over the next three years, I will continuously develop more content to educate the American public on where, when, and how to view this amazing spectacle. You'll find many new eclipse maps, videos, historic items, and other resources that you can share with friends and family.

I'd also like to invite other eclipse enthusiasts to participate in the on-going development of this website. Do you have something of interest to say to the readers of this blog? Send me some text and a picture and if it's of quality, relevant, and is your creation, it will be posted here.

I'm building some eclipse photo galleries that will be available soon on this website. Do you have any excellent eclipse photos? Not just corona pictures, but photos such as people viewing the eclipse? Send them with a description and a link to your website and they might appear in the gallery.

Do you have ideas or suggestions for improving this website or making it a community resource?

You can reach me at and I look forward to collaborating with you.

Michael Zeiler

Santa Fe, New Mexico




Second US Solar Eclipse 2017 Planning Workshop Live Event

From Mike Kentrianakis on the Solar Eclipse Mailing List (SEML) today:

Live coverage of the second US Solar Eclipse 2017 Planning Workshop will be held in Columbia, Missouri, on August 21st and 22nd starting at 9:00am CDT each day. Live coverage will be offered via Ustream.
Workshop Agenda:

Ustream URLs:

Ustream app downloads (for mobile devices):

AAS US Solar Eclipse 2017 webpage:

I was at the first 2017 planning session and I regrettably can't make this meeting. But now I can follow the proceedings at my desktop!

Thousand Year Canon of Solar Eclipses

An important new book has just been published by the leading authority on eclipse predictions, Fred Espenak. The significance of this book is its increased accuracy based on a new JPL ephemeris and the organized presentation of essential eclipse data. 

Fred previously published the Fifty Year Canon of Solar Eclipses: 1986–2035 and Fifty Year Canon of Lunar Eclipses: 1986–2035, co-authored Totality - Eclipses of the Sun  with Mark Littmann and Ken Willcox, and co-authored the Five Millennium Canon of Solar Eclipses: -1999 to +3000 with Jean Meeus. Fred is well known in the eclipse community for the essential eclipse bulletins produced during his tenure at the NASA Goddard Space Flight Center with maps and weather analysis by Jay Anderson. 

From the book description:

"The Thousand Year Canon of Solar Eclipses 1501 to 2500 - Color Edition contains maps and data for each of the 2,389 solar eclipses occurring over the ten-century period centered on the present era. The eclipse predictions are based on the Jet Propulsion Lab's DE406 — a computer ephemeris used for calculating high precision coordinates of the Sun and Moon for thousands of years into the past and future.

Section 1 of the Canon presents fundamental concepts including eclipse classification and the visual appearance of each type of eclipse. Section 2 discusses the eclipse predictions, the constants used and Delta T. A statistical analysis of eclipse frequency, extremes in eclipse magnitude, greatest central duration and quincena combinations are covered in Section 3. A concise explanation of the data contained in the solar eclipse catalog (Appendix A) appears in Section 4 while Section 5 offers a complete description of information presented in each of the solar eclipse maps (Appendix B).

The primary content of the Thousand Year Canon resides in the two appendices. Appendix A is a comprehensive catalog listing the essential characteristics of each eclipse. These include the calendar date and time of greatest eclipse, Delta T, lunation number, Saros series number, gamma, eclipse magnitude, geographic coordinates of greatest eclipse, Sun's altitude and azimuth, central path width and central line duration. Appendix B is an atlas of maps depicting the geographic regions of visibility of each eclipse. The zones of partial eclipse and central eclipse (if applicable) are plotted on an orthographic projection map of Earth. The 2,389 maps are arranged twelve to a page at an image scale permitting the assessment of eclipse visibility from any location on Earth. Other data on each map include the eclipse type, calendar date and time of greatest eclipse, Saros series number, lunar node, Delta T, gamma, Sun's altitude, and central eclipse duration or eclipse magnitude.

The key feature of the Color Edition is, of course, the fact that all the eclipse maps in Appendix B are reproduced in color. Since each of the curves making up an eclipse are color coded, this greatly aids in interpreting the maps. For example, the central path of total eclipses is plotted in BLUE while annular eclipses are RED."

This volume will no doubt become a well-worn addition to the bookshelf of eclipse enthusiasts.

Solar Eclipse Conference 2014

In two months, eclipse chasers from around the world will gather at Cloudcroft, New Mexico for the fifth Solar Eclipse Conference on October 25 and 26. Many of the leading experts on solar eclipses and solar physics will gather for an exciting program of talks on every aspect of eclipse observation and science. Conference registration is closing soon so if you are passionate about eclipses, considering attending this event.

There are also pre-conference sessions on August 23 and 24 at the nearby National Solar Observatory at Sacramento Peak. These dates coincide with a partial solar eclipse on October 23rd. 

From the conference organizer Patrick Poitevin: 

"Over the last few decades, there have been dramatic changes in solar eclipse traveling. Solar Eclipse specialists meet most of the time in the shadow of the Moon. Solar Eclipse meetings out of totality are rare, or are mainly focused on solar physics. The Solar Eclipse Mailing List and before the Solar Eclipse Newsletter has been successful as a vehicle in bringing together solar eclipse enthusiast, professionals and amateurs alike. Because there was no central eclipse in 2000 we had been presented with a perfect opportunity for an International Solar Eclipse Conference.

We had had this project in mind for some time, but mainly due to planning eclipse travels it has been put on hold. The aim of the conferences is to bring together professionals and amateurs, addicts, enthusiasts, and chasers, as with the mailing list and the newsletter, sharing information, knowledge, and experience. For the same reason we organized an international Solar Eclipse Conferences in 2004 and 2007.

Two days of lectures are given in each of the disciplines: predictions, mathematics, solar physics, weather forecasting, eye safety, diameter measuring, edge and central, and ancient eclipse research. Of course the latest and forthcoming solar eclipses should be great topics of discussion, along with the once-in-a-lifetime Venus Transit. Friday evening is a social event with reception and informal meetings. And where possible the conferences is combined with a lunar eclipse, partial solar eclipse and a visit to a solar observatory."

The Great European Eclipse of 1999

Fifteen years ago today, Europe experienced a total solar eclipse with broad similarities to the 2017 American eclipse. It traversed the continent from the northwest to its southeast, it was roughly the same duration (a little more than 2 minutes), and millions of people were able to see this spectacle. 

This is the BBC presentation from that day. Here are some more video links:





I remember that day well. My intended place for observation was in the place of my birth in southern Germany. But on the previous day, the weather forecast for Germany was grim. So I dashed to Austria and drove and drove to escape the cloudy weather. 10 minutes before totality, I finally stopped in a farmer's field very close to the Austrian-Hungarian border and saw the breathtaking corona.

Each total solar eclipse is different and the vision of each is seared in your memory. My impression of this symmetric corona was that it appeared as a ghostly sunflower in the sky.

Darkness at Noon, 1806

I am lucky to have in my collection Darkness at Noon, an early pamphlet on the June 16, 1806 total solar eclipse which passed over New England. This remarkable document by Andrew Newell narrates the theory of eclipses, describes local circumstances for the 1806 eclipse, tells the reader how to view the eclipse, and dispels superstitions surrounding eclipses.

This pamphlet is scanned in its entirety in the gallery. 

From the introduction:

"The Science of Astronomy, in all ages, has been a subject of superlative excellence. By its discoveries, knowledge has been diffused in rich variety over the face of the civilized world; and imagination has found a field where it can rove without restraint of limitation."

"The discoveries which have been made in this science within the last three centuries have exceeded the warmest expectations of human reason; for the mind, which was once limited to the narrow confines of a little earth, is now able by the telescope to travel space, and make excursions into the distant regions of the heavens; and a prospect is now opened to us, as wonderful as it is infinite."

Dubious advice for viewing the eclipse (by present standards) is given on page 12.

Pages 13 through 29 give a competent, if verbose, narrative on the causes of eclipses.

Page 30 begins with the counterintuitive but correct notion that "Eclipses of the sun are more frequent than those of the moon; but, we have more visible eclipses of the moon than of the sun, because a lunar eclipse is seen from all those places on the earth which are directed towards her"

Page 32 gives a list of eclipses visible in New England from 1778 to 1811.

Pages 35 and 36 tabulate prominent solar eclipses from 431 BCE to 1438 CE.

As I look at this pamphlet again, it strikes me that the purpose of this 1806 pamphlet are identical to the goals of I will endeavor to do as well.

An epic canon of eclipses

One of the 160 maps in the Canon der Finsternisse showing eclipses from 2008 to 2030

One of the 160 maps in the Canon der Finsternisse showing eclipses from 2008 to 2030

Among eclipse cognoscenti, the Canon der Finsternisse (Canon of eclipses) by Theodor von Oppolzer (1841-1846) stands alone in the pre-computer era as the epic compendium of eclipse calculations and maps spanning over three millenia. 

Theodor von Oppolzer was a mathematician, geodesist, and astronomer and published many papers with computations for orbital elements of asteroids and comets. Oppolzer observed the solar eclipse of 1868 August 18 and was inspired by this event to begin the calculations of solar eclipses which culminated in his Canon nearly 20 years later. Oppolzer organized a group of ten human computers to divide the task of calculating 8000 solar eclipses and 5200 lunar eclipses. For each solar eclipse, points were calculated for the begin, end, and mid-point of eclipse and circular arcs were drawn between the three points, resulting in considerable inaccuracies in the geographic locations of eclipse paths.  

Within the Canon, the circumstances of the solar eclipses were summarized in a set of 160 tables with correlating maps. Each table and map represents a set of 50 successive solar eclipses. The fact that each table and map contains exactly 50 eclipses explains why they span irregular intervals of about 20 years, plus or minus a year or two.

Sadly, Oppolzer did not live to see the completion of his opus; he died the year before its publication. He is reported to have inspected the final proof-sheets of the Canon in the hours before his death at the age of 45.

The original Canon der Finsternisse is exceedingly rare and is found only within university or observatory libraries. In 1962, the Canon was reprinted by Dover Publications and translated into English by Donald Menzel and Owen Gingerich. I was fortunate to meet Owen Gingerich during the 2012 transit of Venus upon Mount Wilson, California and have his signature inside the front cover of my copy of the Dover edition.

An ancient eclipse computer

By Tilemahos Efthimiadis from Athens, Greece [CC-BY-2.0 (], via Wikimedia Commons

By Tilemahos Efthimiadis from Athens, Greece [CC-BY-2.0 (], via Wikimedia Commons

Probably the most astounding artifact from antiquity is the Antikythera Mechanism discovered in 1900 at an ancient shipwreck off the Greek island of Antikythera. This gearwork was dated to approximately 100 BCE and was quickly recognized as a remarkably advanced piece of ancient technology. This degree of sophisticated gear technology which was not attained again until the 14th century in western Europe.

Over the 20th century, many theories were developed to divine the purpose of this gearwork. In recent decades, considerable progress has been made by The Antikythera Mechanism Research Project and it's purpose is now clear: this mechanism was devised as a computer for the prediction of possible dates of solar and lunar eclipses.

A new research article Eclipse Prediction on the Ancient Greek Astronomical Calculating Machine Known as the Antikythera Mechanism has just been published by lead scientist Tony Freeth. From the abstract:

The ancient Greek astronomical calculating machine, known as the Antikythera Mechanism, predicted eclipses, based on the 223-lunar month Saros cycle. Eclipses are indicated on a four-turn spiral Saros Dial by glyphs, which describe type and time of eclipse and include alphabetical index letters, referring to solar eclipse inscriptions.
The ancient Greeks built a machine that can predict, for many years ahead, not only eclipses but also a remarkable array of their characteristics, such as directions of obscuration, magnitude, colour, angular diameter of the Moon, relationship with the Moon’s node and eclipse time. It was not entirely accurate, but it was an astonishing achievement for its era.

Three aspects of the Antikythera Mechanism are particularly striking;

  • the advanced level of metal gear technology which arose in a Greek colony and was lost for 15 centuries,
  • the sophisticated understanding of the motions of the Sun, Earth, and Moon by Greek astronomers which were applied to eclipse prediction, and
  • the importance of solar and lunar eclipse predictions to ancient cultures.



The first eclipse map in the American Ephemeris

Eclipse map showing the extent of the partial solar eclipse over northeast North America and much of Asia. 

As this website is inaugurated, it's appropriate to recall the launch of the American Ephemeris and Nautical Almanac in 1855. Ephemerides had been published since antiquity with predictions for the motions of heavenly bodies and solar eclipses were always prominently documented, usually with maps.

With this map, the United States Naval Observatory (USNO) began publishing eclipse maps of each eclipse that occurred for the year of publication. This publication of eclipse maps continues to this day in the Astronomical Almanac jointly published by the USNO and Her Majesty's Nautical Almanac Office (of the United Kingdom).

One of the key missions of is to continue this eclipse mapmaking heritage with the publication of detailed and informative maps of the 2017 total solar eclipse for the public. Eclipse maps are special due to their ephemeral nature; they are good for only one area at one specific moment in time! An eclipse map invites you to see the breathtaking sight of a total eclipse of the Sun.

You'll find this and many more historic and contemporary eclipse maps at the sister website of,