Archive for the ‘ECLIPSE CHASING’ Category


August 2, 2010

My 20th eclipse expedition was to the Argentinian Patagonia in austral winter.  We were at the end of the eclipse track, at sunset, when scattered clouds will more easily block the eclipse view.  Worse, the eclipsed Sun would be over the frequently cloudy Andes, increasing the likelihood of blocking clouds.

But we had no worries.  We would be flying through the eclipse track over the South Pacific, having clear skies and an extra minute of totality. But two days before I left, the plane we were to use was taken out of service for major unscheduled maintenance.  There were no other planes available.  We would be ground based.  I thought that we had a small likelihood of seeing it–well under 5%.  On the way down, I almost missed my connection because of thunderstorms and decided if I missed the plane, I would go home.  Two things kept me going:  (1) I don’t like to give up and (2) If I didn’t go and they saw the eclipse, I would never forgive myself.  I made the plane to Buenos Aires with 10 minutes to spare and was in Argentina 10 hours later.

At lunch on the holiday, two days before the eclipse,  I sat next to Maria, a young German astrophysicist.  She discussed her research so clearly that for once I said little, just listened, and learned a great deal.  She was involved in sending a satellite to the L2 LaGrangian point, one of the places where the Earth and Sun’s gravity balance each other.  I thought there were only 2 such points; there are 5.  I learned a lot of other things, too, since I just stayed quiet.  Turned out that my allowing Maria to talk was exactly what she needed.

When we started discussing eclipses, I learned that Maria got under the wrong cloud and missed the 1999 Munich eclipse that went over her home.  To put it mildly, Maria was primed to see this one from the air.  But now there was no plane and she had limited winter gear, because she hadn’t expected to see it from the ground.   Like all of us, she was was emotionally devastated, and 2 days prior to the eclipse, the predictions were not good.

I told her my many close calls and said, “Maria, it isn’t over until the eclipse is over and we didn’t see it.” That afternoon, I talked with her on the tour about eclipses, trips, physics and travel.  She was smart, curious and articulate.

Prior to leaving Buenos Aires, I was online alternately looking at South American weather models and flight delays, since the air traffic controllers had a slowdown.  But, the controllers behaved, we got on the plane and flew to El Calafate the day before the eclipse, for InterSoles, an eclipse conference where Maria and Anita, astrophysical colleagues, were speakers.

During the conference, several noted my constant looking at my watch, which has a barometer.  It was rising, which it had been predicted to do, even though the sky was completely overcast by evening.  Every free moment, I was on the computer, willing the weather models to improve.

The barometer continued to rise.  It remained overcast.  After dinner, I was in my room,  now learning the IR model for South America showed the moisture fetch that had slammed Chile had stopped and shifted north. I was cautiously optimistic.  I don’t sleep well during the night before an eclipse and was up at 4, looking out at a sea of stars.  The barometer had risen a whopping 13 mb overnight.  My optimism increased.

After breakfast, we went outside where Maria saw the Southern Cross for the first time.  The ISS flew over as well.  This was a good start to the day.  On the ride to Perito Moreno glacier,  I got the idea of stopping, since we were well out of town, and allowing the riders to view the Magellanic Clouds under a dark sky, since we couldn’t see them at the hotel.  It is highly out of character for me to stand in front of a bus of many strangers, and ask if they minded if we stopped.  Nobody objected, and everybody got a great look.  I was relieved.  Now Maria had seen the Magellanic Clouds for the first time.

We spent 2 hours at the glacier, listening to icebergs calve, watching sunrise on the mountains.  On the return, I was now in full worry mode.  Still clear skies,  I worried about mountain convection and orographic lifting that comes in the afternoon.  The eclipsed Sun would be a degree above the horizon, so any significant mountain cloudiness would be a problem.

On the way up the single track to a high plateau, over El Calafate and Lago Argentino.  I saw a cloud.  My worry increased.  At the site, I saw a large lenticular cloud sitting on a mountain to the southwest, spewing clouds to the north, but for at least an hour, they dissipated.

Then I noticed more lenticular clouds further north, and the clouds no longer dissipated.  The eclipse was 2 hours away, and I didn’t like the weather.  I willed the Moon to move faster.  The eclipse began, and as the Moon moved during the 65 minutes it would take to cover the Sun, I realized that sunset would be much further north than I had been told.  There were no clouds in that area, and 30 minutes before totality, I knew we were safe.

Maria joined me, used my binoculars, and did what many do during an eclipse–cried.  It WAS beautiful.  She had gotten the perfect end to her day–a dream came true, a total solar eclipse visible in a clear sky.  Had we been on the plane, the view wouldn’t have been nearly as good.

This was one of the most difficult eclipses I’ve gone to.  It was one of the most beautiful ones.  And the reaction from Maria was the strongest emotion I’ve ever witnessed.  All eclipses are memorable; this one is at the top.

It isn’t over until it is over. And sometimes, good things come out of what seems to be bad luck.


July 12, 2010

Yes, we did see this.  And we were lucky.  My video on YouTube was a simple camcorder set up facing the Sun and then left running, while I and Maria, a young German astrophysicist, watched.  This was Maria’s first eclipse, and she wanted to see it more than anybody I’ve known.  Her crying is not unusual; total solar eclipses are beautiful, primal, spiritual events.  They affect us deeply!

This was my 20th eclipse trip:  I’ve seen 11 total eclipses (this was my 12th), 5 ring (annular) and 3 times missed from clouds, wind or rain.  This trip featured a flight over the S. Pacific along the track, which is why I and many others signed up for it.  Seeing it from a plane is a 100% probability as opposed to the ground, especially on islands, where mobility is limited if there are eclipse blocking clouds.  Unfortunately, a week prior to the eclipse, the plane was taken out of service for major mechanical problems (or so we were told).  We had no plane and were going to see the eclipse in the worst possible spot:  the Argentinian Patagonia in mid-winter at the end of the eclipse track.  I’m a weather junkie, and all the models were pessimistic about clear skies in Patagonia for eclipse day.  Worse, because of the low position of the Sun, ANY significant horizon cloud would kill the eclipse.

I almost didn’t get out of the US.  Tucson to Houston flight was diverted to San Antonio because of T-storms over Houston.  I got to Houston at the other end of the airport from the Intl Terminal, plane to depart in 25 minutes.  Frankly, because of the lack of the eclipse flight and the distance traveled to likely see nothing, I would not have minded missing the plane and going home. But I did make the plane and was in Buenos Aires the next morning.

We stayed in B.A. 2 days then flew to Patagonia (more worries, because there had been an air traffic control strike as well which had cancelled many flights and made many others late) and got there with mostly cloudy skies that worsened as time progressed.  However, I knew high pressure was building in the eastern Pacific, and more importantly, the water vapor fetch that had been slamming into Patagonia shut off the night before the eclipse.  We had clear skies the next morning.  We first went out and viewed the southern sky and saw the ISS pass overhead.  On the way to the glacier, I got the idea to stop the bus and view the Magellanic Clouds from a dark site.  I was a bit nervous about holding everybody up, but NOBODY vetoed the idea, and several who had never seen them before got a chance.

The glacier was fine, the skies completely clear, the wind light.  I was starting to get optimistic, which is an oxymoron when used in conjunction with eclipse day.

We left the glacier at noon and were back in El Calafate at 1:30.  We got into 4  x 4s that held 15 people, had chains, and went up a single track that topped out about 3000 feet above the town and Lago Argentino nearby.

The views were stunning.

By this time, there were clouds on the mountains, which worried me, although they were mostly lenticular and were dissipating as they moved north, about where we were told (wrong, as it turned out) where the Sun would set.  First contact, where the Moon begins to cover the Sun, occurred about 1 hr 5 min before totality.  It couldn’t happen soon enough.  Clouds were starting to build on the mountains.  But when we realized that the Sun couldn’t possibly set where we were told it would, I finally relaxed, knowing that everything would be fine.

It was a beautiful eclipse.  Photographs, especially mine, don’t do it justice.  The corona was not particularly impressive, but the low Sun and the long, beautiful diamond ring were.  What captivated all of us was the shadow cone, as the Moon’s shadow lengthened as the Earth curved away from it.  This is captured very well on the photographs, and I saw it head into space after the eclipse was over.  It just appeared as a darker than normal area of sky.

Each total solar eclipse is special in its own way.  This one will be remembered by me for three things: (1) the difficulty getting there and my constant checking of multiple weather models of the south Atlantic, (2) the stunning shadow cone, and (3) Maria, a delightful young astrophysicist who had never seen a total eclipse before, desperately wanted to see this one, and joined me.  She was so moved, she was crying, not at all an unusual emotion, and one that is captured on the video.  I want all first timers to see the eclipse.  Of course, I want to see it, but I’ve seen them before, a first timer has not.  Watching the awe on their face when they see what we’ve been discussing is truly remarkable.

The eclipse was my 12th total solar, and with Russia, was probably the toughest, most worrisome one we saw.  But we caught a break in Patagonia and had 2m40s of totality.  Were we lucky or what?


February 7, 2010

Foregoing the elevator, I went to the stairwell at the Nairobi Intercontinental, ascending to my third floor room.  When I reached the spacious second floor, there were a dozen hotel workers taking a break.  When I appeared, an old white western guy, the scene got–shall we say–awkward.  Their conversation stopped.

I smiled and said, “Jambo,”  an all purpose Kenyan greeting, one from the heart, my guide, Danson, told me several days later.  I heard several “Jambo’s” in return, and tension left the stairwell like air from a popped balloon.  I continued up the stairs, and they continued their conversation.  Trying to speak the language in another country is a sign of respect.  “Jambo,” told the men that I was cool with the situation, I knew a little KiSwahili and was a guy who respected Kenyans as people, not former colony inhabitants.

One of my big regrets in life is never having learned any foreign language well.  Still, within 12 hours of arriving in Nairobi, I could count, say please and thank you, and “Jambo,” which I used a great deal, along with “Hakuna Matata,” the Kenyan version of “Don’t sweat it.”  My French in France was not appreciated.  But my Spanish worked in Spain (and not badly in Italy, either), and the Filipinos absolutely loved it when I spoke Tagalog, 35 years ago.   I blew one vendor away with my “Hindi ako kumakain nang barbeque dito,” essentially stating I wasn’t interested.

At Lake Nakuru, I showed several lodge staff the annular solar eclipse through solar filtered binoculars, the eclipse being the reason I traveled to Kenya.  I love eclipses, and I love showing them to people and explaining the phenomenon.  Many were flat out amazed a guest would take an interest in making sure they could see something that almost certainly they will never see again (the November 2013 eclipse will be partial in Kenya).  In the short time I was there, many called me “Mr. Mike,” an appellation I particularly like, since it simultaneously shows respect and liking.  I told one waiter my age was sitini na moja, (look it up!)  It took him a few seconds, but he got it, and later (in English) talked to me at length about the lodge.  Danson later told me that I had made a big impression on the staff, one of the nicest compliments I received.

People are people.  Just like me.  The Kenyans have a life, a far more difficult one than I can imagine, but they are still people.  Unlike us, they have a beautiful memorial site for their disaster of 7 August 1998. Also unlike us their cellphones work everywhere.  I texted the eclipse phenomenon in real time back home. My text immediately went through from Jomo Kenyatta airport; it didn’t from Houston’s Intercontinental.  Not infrequently, I get “No Service” from Campbell and Skyline.  So who is Third World?

When I left practice in 1992 to take a leave of absence, I received many notes, cards and letters.  The one I remember the most was from a dietitian, who was also leaving to go to pharmacy school.  She said, “You respected the little people.”  I tried to.  I was taught at a very young age not to beat up on those who can’t defend themselves (nurses, custodians, aides), which I have done and for which I have been ashamed.  I’ve seen too many physicians and others in power who beat up on people, and I remember taking the brunt of it when I was an intern scrubbing on a bypass case.  It was difficult to hold the retractor properly when my eyes were filled with tears.  I was thanked only 5 of the 12 times I scrubbed with those two surgeons.  I was the little people, and I never forgot that treatment.  It was so bad, I got blisters on my hand from learning how to take a hemostat off a piece of wet kleenex with one hand without tearing the kleenex, so I wouldn’t get yelled at in the OR.  And I mean yelled.

I finally got some revenge.  On a later case, with the pair, I had my thumb too far through a hemostat.  “Don’t hold your instruments like that, Smitty,” one yelled (a term I detest), “you don’t hold your silverware like that, do you?”

“I don’t use silverware,” I retorted.  “I use my fingers.”  That was the end of that conversation.  When they quizzed me on anatomy, which I happened to know cold, I spat the correct answer back at them.  After three correct answers in a row, they left me alone.  One later had a nervous breakdown; both must have been incredibly unhappy people.

I always thanked nurses for helping, I tried to clean up after myself, and if you read Code Team on my blog, you will discover what other things I cleaned up in the hospital.  But occasionally I lost my cool.  We all do.  I just tried to remember to apologize when I did.  And if one is polite most of the time, he or she can easily be forgiven for a lapse.  There just can’t be too many of them, and an apology,must be coupled with a change in behavior.

When you’ve been at the bottom as many times as I have–undergraduate, medical school, internship, residency, graduate school and now teaching, you understand a lot better what it’s like being the little people.  That gives you two choices:  to haze those below you or to break the cycle.  I’ve tried to choose the latter.


January 15, 2010

I must be crazy to fly 10K miles to risk getting clouded out.  But eclipse chasers are a bit nuts.  And while it was another nail biter (thick clouds still over the Sun with 30 minutes to annularity, but then they started to burn off), it was a successful trip.   The three photos across show second contact (Moon just inside the Sun), mid-annularity and third contact (Moon just inside the Sun–leaving it).   Then there are two slide shows of wildlife and a final slide show of the eclipse site, the people, the cloud bank that sooooo worried us and other eclipse shots.  The final shot is mid-annularity.  Click on it and the stretching will disappear.  The video is on YouTube of both the eclipse and the safaris.  I shot the stills with a Canon 12x optical, hand held, through a Mylar filter.  The video was shot through a Panasonic S26 camcorder and Mylar filter (you can see that on some of the eclipse stills.)  The sandwich video has wildlife-eclipse-wildlife with stills pasted into the video.  The first three pictures below were taken from the video, put on full screen, photographed and sent to iPhoto.  Tried to do all of this at Nakuru but the wifi was slow and occasionally the power went out.  I’m the guy wearing the True Value hardware cover (good to store filters and other stuff quickly during an eclipse).  We had a polyglot group (well, not me, other than my very limited KiSwahili), with Russian and Japanese being the other languages.  People just appeared, and next to seeing an eclipse, showing it to people and explaining the phenomenon is as enjoyabl as well.  This was my fifth annular, and  I’ve seen 11 totals.  Total eclipses are much more beautiful, but annular ones are pretty neat.  It’s just that I usually need a very good excuse to go to one.  Kenya provided that excuse.

Next total 11 July 2010–I’m heading for El Calafate, Argentina and will fly it, hoping to see it over the southern Chilean Fjords.


December 30, 2009


October 4, 2009

First trip:  11 July 91 to the Baja to see the 6 1/2 minute total solar eclipse.  We didn’t plan on seeing any others, but about a year later PBS had a special on that eclipse, and we both asked, “when and where is the next one?”  That’s a sign one is getting hooked!

Second trip:  3 November 94 to Sevaruyo, Bolivia.  We called that the trip where every other night we had a bed.  I was altitude sick for a day in La Paz, and then we took the train south to get into the track.  Most memorable moment (and remember, this is 1994):  the train stops in the middle of nowhere in the middle of the night.  Somebody asks, “Where are we?”  Simultaneously, about 5 people say “18 degrees South 64 degrees west.”  Totally correct and completely useless!

Third trip:  24 October 95 to western India.  This eclipse was a guarantee on weather for days before.  We saw birds roost about 10 minutes before totality.  Because totality was so brief, we saw the chromosphere (the inner atmosphere) of the Sun for the whole time.  It was a lovely lavender.  I would put the shot on here, but my cable release broke prior and using my finger caused some blurring.  It may have been the prettiest I’ve seen.

Fourth trip: 9 March 97 to Siberia.  That is described elsewhere in this blog.

Fifth trip: 26 February 98 to Aruba.  We went to the south end of the island, where it started to rain.  We went back north and saw it in cloudy but adequate skies.  Had we stayed put, we would have been just fine.

Sixth trip: 21 June 01 to Zambia.  Jan had broken her humerus and had external pins in.  I could have been a nice husband and stayed home to help her.  Or I could have gone to the eclipse, which I did.  We saw totality about 50 miles north of Lusaka, the capital.  It was the only eclipse trip I was on where everybody in the group was silent.  That in of itself was probably the weirdest experience of all!

Seventh trip: 23 November 03 over Antarctica.  We flew to Punta Arenas  Chile, then took a couple of days to see Torres del Paine, a remarkable formation of climbable (not ever by me!) rocks.  We then took a Lan Chile flight with open cockpit (meaning you could look over the pilot’s shoulder, especially when he was taking pictures himself), getting totality somewhere around 73 degrees south latitude.  We then flew over the South Pole from an alititude of 2500 feet.  We came back over the Presidential range, flew around Vinson Massif twice and came back to Punta Arenas.  It was a 14 1/2 hour flight.  Next afternoon, we caught flights to Santiago, Lima, LAX and finally Tucson.


Torres del Paine:


Magellanic Penguin:


Antarctica Mountains:  The clarity of the air and the starkness of the shadows were remarkable.

Below is the South Pole station.  While we flew over (two passes), a C-130 cargo plane took off.  The contrail at the surface was incredible to see.   DSCF0031

Vinson Massif, highest mountain in Antarctica:


Eighth trip:  8 April 2005 to the South Pacific.  We flew to Tahiti, took a cruise by Pitcairn and Easter Islands, then ended in Callao/Lima.

This is right after totality.  The dark clouds are the departing Moon’s shadow.DSCF0154

DSCF0100The author, with Pitcairn Island in the background.  It was too rough to land.  We really lucked out with this eclipse, because a low pressure system suddenly strengthened to our south.  Meteorologist Jay Anderson had the captain move us further northeast along the track the night before.

DSCF0110This is Tongariki, where the Moai were ordered.  I found that and Anakena interesting, but the quarry was to me the real Easter Island (below).


Ninth trip:  29 March 06 in Libya.  We flew to Genoa, Italy and cruised to Naples, Syracuse, Alexandria, and landed at Tobruk, where we saw the eclipse inland.    As you can hear in the video, when totality occurred, a bunch of Libyans in cars came honking across the desert like a modern day Lawrence of Arabia.

Tenth trip:  1 August 08 in the high arctic, by air.  Unfortnately, our window was very icy, and our view was significantly degraded.  Efforts to try to find out why this occurred were totally stonewalled, which I think is unfortunate.  Still, we did see totality, and anybody who goes to Eliot Schechter’s web site will see a shot of totality taken from the plane at 36,000 feet (11,000 meters).

Here is our shot of the North Pole:IMG_0691

And proof of sorts:IMG_0689

Eleventh trip: 22 July 09, south of Shanghai China.  This is about as close to missing one without actually doing it.  After days of high humidity and record temperatures, a front sagged south on eclipse day.  We moved south, but alas, the front followed us, and while we had good views of the Sun 2 hours before, it clouded over until 2 minutes before totality.  Then we got this:IMG_1477 Not impressive, but we did see the corona.  Because of the thick clouds and the length of this eclipse, we had a wide shadow and it got dark.  Really, really dark.  Eclipses normally drop the light to late twilight.  Not this one.  It was NIGHT!

11 July 2010:  See the related post on this one.  We were supposed to fly and then the plane got cancelled.  We got one clear day in the austral winter and got one great eclipse!


October 3, 2009

Why have I traveled all over the world, at least to six continents and have flown over both poles, to view a total solar eclipse?  Because I caught the bug back in 1991, July 11 to be exact, when the 6 minute and 27 second spectacle was visible from our hotel.  I have the comments on tape somewhere, and I remember that I uttered sounds I didn’t think I could make.  This is a brief You Tube video of the last seconds before totality, the Diamond Ring, and early totality from Libya in 2006.  I have a better video of the recent 2010 eclipse from Argentina (link here or at end of this post).

People are changed by the experience.  Some cry.  I was a bit frightened during my first four when I saw the Sun disappear.  This is primal stuff.  But it is beautiful.  The most beautiful sight in nature?  Maybe.  It is certainly for me in the top three.

After a little bite is taken out of the Sun (first contact) by the Moon, the show progresses very slowly at first, until suddenly one realizes that sunglasses are no longer needed and that the light has changed to a weird yellowish cast.  As the light continues to slowly dim, one’s shadow becomes very stark–each hair on your head can be discerned.  Holes through leaves in trees become crescents, hundreds of crescents.

Then, with a few minutes to go, there appears a dark wall in the west as if a silent thunderstorm were approaching.  This is the approach of the shadow of the Moon.  The light diminishes to where there are discontinuities where the limb of the Moon, which is not perfectly spherical, but has mountains and valleys, lets some light through and blocks other light.  These are the Bailey’s beads.  Finally, one bead is left, one brilliant last bit of sunlight, with the beginnings of seeing a black hole around a bright light and silvery fine corona.  This is the diamond ring, and usually people shout it out.  Finally, the sun light is extinguished, somebody yelling, “Filters off!” since it is now safe to look with the unaided eye.  And there is the corona and the black hole in the sky, a total solar eclipse.  I’ve traveled half way around the world to India for 43 seconds of totality; I’ve traveled to the South Pacific for 33 seconds.  I’ve traveled to South Africa only to be clouded out at the last hour.  And in China, last July 22, we were thought to be clouded out when, with 2 minutes to go until totality, a small hole appeared, giving us a view of the corona.  Click on the pictures below to see them fully round, rather than oblong!

Why do I go to these?  Because I can’t imagine not going!

Above:  scan0003Just before the diamond ring (Aruba, 26 February 1998).  Below shows totality with the corona.  There is an inner and outer corona that show up depending upon exposure of the camera.  I don’t film these any more, but if you want to see some really good shots, my good friend Eliot Schechter, a nationally known photographer, has some great shots on his Web site.   His picture of a totally eclipsed Sun with the dark Moon’s shadow taken from a jet was the 1 August 2008 eclipse over the high arctic.

There are also annular, or ring, eclipses, where the Moon does pass in front of the Sun but is too far away from the Earth to cover the Sun completely.  Both the Moon and Sun vary in their distance from us; the Sun’s variation is only about 3%, but the Moon’s is 12%.  This changes their apparent size in the sky, and that is all it takes to turn totality into annularity, darkness to a little less bright.  Still, annular eclipses are beautiful to see.  The above was taken in Bisbee, AZ 10 May 1994.  The lower was in San Diego 4 January 1992.  We were told by several that annular eclipses weren’t worth a trip to San Diego.  I believe the word was “Big Deal.”  We left Tucson in the rain, and got to San Diego with partly cloudy skies.  We parked ourselves on top of Mt. Cube and watched the fully annular eclipsed Sun drop into the Pacific Ocean.  Maybe it wasn’t total, but it was one of the most lovely sights I’ve ever seen.  Two hours later, it was pouring rain.  We lived right!


The most exciting of all was the Siberian eclipse of 9 March 1997.  That’s right, Siberia in March.  We went the long way around via Salt Lake, NYC, Moscow and an all night flight to Irkutsk.  After a couple of days on frozen Lake Baikal, we took the Trans-Siberian railroad to Chita, which even our guide referred to as a “hole.”  While it had been clear the night before, it was totally socked in at Chita.  Thoroughly bummed, the 12 of us took a bus to the eclipse site.  As we got closer, the clouds thinned and the Sun rose higher.  We got to the site with a clear view of the Sun!  What I remember most was watching the approach of the Moon’s shadow, the “Eye of God.” approaching.  I have never seen anything so dark.  And then to watch four planets, a comet and the eclipsed Sun for just under 2 minutes.  I tried photographing it, but the below zero temps froze the camera.  I just dropped it in the snow and looked.  That was better!  Let the pros do the shooting.  I’ll do the looking!  Very few saw this one; we were among the lucky!


Next total solar eclipse: 14 November 2012 in northeastern Australia and SW Pacific basin.  The above picture was the Moon’s shadow leaving our site in Libya 29 March 2006.  It is noon, if you can believe it!

The recent annular eclipse of 15 January 2010 is on another post with both pictures and a video.  We’ve gone to Spain and Costa Rica for annulars (picture to right taken through a filter of the 3 October 2005 eclipse from Javea, Spain)  but usually don’t travel long distances for them.  But I got the bug for this one, the longest annular in the third millenium (over 8 minutes), and Kenya provided a great excuse, since I had never been to East Africa and never thought I would get there.   The next annular eclipse, 20 May 2012, has a track from northern California through Nevada, southern Utah/northern Arizona, New Mexico, ending in west Texas.

Visit the post for the recent 11 July 2010 eclipse from Patagonia, Argentina.  In a word, we were lucky!


September 13, 2009

Next annular solar eclipse, 15 January 2010.  I hope to be in Kenya for it.

Next total solar eclipse, 11 July 2010.  I hope to fly it from El Calafate, Argentina, viewing it over the Chilean fjords.

Three things are necessary for an eclipse of the Sun.

  1. The Moon has to be new; that is, between the Earth and the Sun.  This is the familiar  29 1/2 day cycle, which is 29.53059 days in length on average (it varies from cycle to cycle).
  2. The Moon has to near one of the nodes of its orbit.  The Moon and Earth’s orbits are very nearly in the same plane, but not quite.  The Moon can be 5.1 degrees above or below the Earth’s plane.  That being the case, the two planes intersect in two places called nodes.  The Moon is large enough that it doesn’t have to be exactly at a node but just near enough to cause an eclipse.  The cycle of the nodes. called the draconic (the dragon eating the Sun) averages 27.21222 days.
  3. The Moon and Earth’s orbit vary in distance from the Earth and Sun respectively.  The Moon can be close to the Earth and appear up to 7% larger than the Sun.  It can be far from the Earth and appear 10% smaller than the Sun.  The Sun varies within a narrower 3% in size, the Earth being closest in January and furthest from the Sun in July.  This anomalistic cycle is  27.54555 days long.  This determines whether an eclipse is total, with the Moon’s completely covering the Sun, or annular, where the Moon is inside the Sun so to speak, with a ring or annulus of sunlight around it.

223 synodic (typical) lunar months are 6585.3216 days.

242 draconic months are 6585.3572 days

239 anomalistic months are 6585.5375 days

18 years are 6574.365 days.

Put in 11 days more (and we have the 18 years 10 or 11 days (leap years) are almost exactly 6585.xxxx days above.  This means that the eclipses will repeat in similar fashion, but that extra 0.3 days moves the next member of the family about a third of the way west around the world.

I hoped this would be explained on one of the eclipse trips I went on but was told by a Sky and Telescope editor that people would think it was too nerdy.  (As if astronomers don’t already suffer that perception).  Frankly, anybody who goes to the effort of seeing one of these spectacles ought to be fascinated by the simple mathematics above!

Eclipses occur, therefore, in what is known as a SAROS cycle.  Each cycle is 18 years and 10 or 11 1/3 days depending upon leap years.  Eclipses are born near the poles as partials, become annular or total (or hybrid, where they are total in the middle and annular at each end), become partial and then disappear.  Each family of eclipses lasts about 70-75 cycles or about 1300 years.  An eclipse that begins at the ascending node of the orbit will start at the North Pole and move south with each family.  A descending node eclipse does the opposite.  The long eclipse of last July (and Baja in 1991, and Kenya in 1973) is Saros 136, a descending node eclipse now past its prime.  It will continue to give use total solar eclipses for the next couple of centuries, but the length of totality will be significantly shorter with each successive eclipse.

On the other hand, the eclipse of 29 Mar 06 has yet to reach its prime.  It will be the American eclipse of 10 April 2024 and will be extremely long in the 22nd century.

Hybrid eclipses mean that the Moon and Sun’s angular size are so closely matched that only at local noon, when the Earth’s curve bulges toward the Moon a few thousand miles, can there be totality.  The 8 April 2005 eclipse was one of those.

Many view eclipses without knowing or caring about all this stuff.  I think it is interesting, so I throw it in for those who are interested!