TOTAL SOLAR ECLIPSE OVER AUSTRALIA, 14 NOVEMBER 2012


This eclipse was not going to be a high probability one to see on the continent.  Saros 133, which is the name of this family member, last seen in South America 3 November 1994, would again visit the Earth 18 years and 11 1/3 days later, this time a third of the way around the world, beginning east of Darwin, crossing the Gulf of Carpentaria, then Queensland, near Cairns and Port Douglas, before heading out into the South Pacific Ocean north of New Zealand.  One per cent of the Earth would be covered by totality, but only a small part of that one per cent would be visible over land.

Cairns, on the northeast coast, is in the tropics, about 17 degrees South latitude.  The tropics have a good deal of convective rain showers, and Cairns had about a 50% probability of one’s seeing the eclipse.

We wanted to see Australia, and if I saw the eclipse, it would be the seventh continent I had seen an eclipse on and over.  But more importantly, it would be another chance–my thirteenth–to see one of the most spectacular shows in the world.  We eclipse chasers are addicted to the sight.

We flew to Melbourne, stayed there for 2 days, getting to know the city, and meeting up with two friends from Germany, one of whom I had met before at the last eclipse, over Patagonia, Argentina, 28 months earlier.  Every eclipse, I meet people from prior eclipses, and this one was no exception.

We then flew to Ayers Rock (Uluru) by way of Alice Springs, and visited the monolith at sunrise and sunset, along with a walking tour, so we could see the caves, the petroglyphs, the sandstone, appreciating that for 60,000 of the 350 million years, people have marveled at this place, making it a sacred spot.

We then left, and flew to Cairns by way of Alice Springs again, this time having time for a tour of the town that is virtually in the center of the continent.

The following morning, Cairns was cloudy, except for a nice hole in the sky, that would have been 15 minutes late, had the eclipse occurred that day.  We went out to Green Island, noting that it seemed to be clearer, although the locals said that it had a similar climate to Cairns.  But it didn’t.  Cairns is deeply recessed from the Coral Sea, with an eastern peninsula that was catching moisture from storms to the south and spilling over those of us in town.

We had decided not to get up at 1 a.m. to go out to Green Island for the eclipse, figuring we wouldn’t have mobility.  The problem was we didn’t have mobility in Cairns, either, to go inland or to Port Douglas, both of which might have been better spots to view the spectacle.

My wife suggested I e-mail meteorologist Jay Anderson, who has achieved fame as an eclipse climatologist and meteorologist.  I have been on several eclipses with Jay, knew he was on a cruise ship for this eclipse, but figured he wouldn’t have time to write me back.  Still, what did I have to lose?

As it turned out, it was the best decision I made during the trip.  Jay gave me a weather synopsis and said succinctly at the end of his e-mail:  “If you can, get offshore.”

In the meantime, I met two Russian friends.  Sergey and Tatiana were at the annular eclipse in Kenya in January 2010.  Sergey works for an oil company in Luanda, Angola, and Tatiana is a travel agent in Slovenia.  Sergey was also at the annular eclipse in the US last May, and we saw it together in Page, Arizona.  Sergey was doing automatic eclipse filming, using programs that were far beyond my comprehension.  He was going to stay on land and hope.  Tatiana would do the same, and she had to fly out of Cairns about 2 hours after totality.  Cairns was flooded with eclipse chasers for several days.

So, at 1 a.m. on 14 November, eclipse day, we awoke and caught the 2:30 a.m. boat to Green Island, setting up on the northeast beach at 3:30.  The sky above us was clear, and darker clouds were behind us, back towards Cairns.  It was easiest the clearest skies we had seen so far on the tirp.  We had great views of the Southern Cross, the Magallenic Clouds, alpha and beta-Centauri, and upside down Orion.

There were clouds on the horizon, but we could see sunrise, and first contact, where the Moon begins to cover the Sun.  As the Sun rose, the clouds increased, and so did the tide, which was due to rise 3 meters 2 hours after totality, at 6:38.  We figured we were safe from the tide, but it rapidly appeared that this would not be the case, so we moved well up on shore.

As the Sun rose further, the clouds began to become a little larger and darker–typical convection in the tropics.  We saw several clouds–one in particular–that were worrisome, when we were only 7 minutes from totality.  But then convection shut down due to atmospheric cooling of 3.5 C from the eclipse itself.

This eclipse had a wonderful diamond ring at both ends (do any not?), with a very delicate corona extending about two solar diameters to the east of the Sun.  It was not a dark eclipse, and there was little red along the horizon, but like the family member I saw in Bolivia, the shadow was visible in the morning sky.  Trees on Green Island prevented us from seeing the shadow arrive, but I had no difficulty seeing it depart.  And two minutes later, the eclipse was over, just like that.

Easily three hundred people saw this from the end of Green Island.  There were experienced chasers and many first timers.

Every eclipse is different, but it is difficult to say whether one is more special than another.  Each person sees something a little different, and each person who is fortunate enough to have seen more than one sees something different.  I try to go through a checklist of things to see with each eclipse, but like my camera and video plans, it usually is forgotten at the critical moment, which lasts on average of 2 minutes, but feels like 8 seconds.  We are left asking….”When is the next one?”  It will be 3 November 2013 in the South Atlantic, ending in Ethiopia.  Getting to that one will be difficult….but not impossible.  We have a connection in Africa–Sergey–who has been to Kampala three times and thinks Uganda is a decent possibility to see 24 seconds of totality–yes, 24 seconds–next year.  We discussed the trip, and several other eclipses coming up, including the long-awaited 2017 eclipse in the US, when we met at Sydney a few days later.

Fifteen seconds of fame:  I was interviewed by Australian TV after the eclipse, while on the boat back from Green Island.  I have no idea if anything appeared on TV.  And while lying in bed that night, I got a call on my cell phone beginning with “44” .  A journalist from CNN in London wanted to interview me about my experience, that I published on CNN iReport.  What is interesting–and discouraging to me–about iReport is that most of the featured pictures were of the crescent Sun.  Few showed the total eclipse itself, which is far more beautiful.  Indeed, the difference between totality and a partial eclipse (even 99%), is the difference between day and night.

Eclipse families:

Currently, there are 13 total eclipses in every 18 years 10 or 11 1/3 days, depending upon leap years and time zones.  Each one of the 13 total eclipses is a member of a family that begins at either the north or south poles and moves the opposite direction over nearly 1300 years or 70-75 eclipses.  Some of these start off as total; most begin as partial, become total or annular for many “visits” and then end as partial.

The reason for this repetition is the 3 requirements for a total eclipse:

Synodic period–New Moon–every 29.530589 days.  The Moon has to be in line with the Earth and Sun.                                                    223 New Moons = 6585.3213 days.

Draconic Period–every 27.21222 days.  The Moon’s orbit is inclined 5.1 degrees to the plane of the Earth’s orbit, and the nodes, where it crosses the Earth’s orbit, are constantly moving.  The Moon has to be near a node when it is new.  This particular eclipse was near the ascending node, where the Moon was near crossing the plane of the Earth’s orbit.                                                  242 Draconic periods=6585.3572 days.

Anomalistic period–every 27.554550 days.  The Moon and Sun are nearly the same angular size in the size, but the Moon’s size can change 12% from our view depending upon whether it is near the Earth or far from it.  The Sun-Earth distance changes about 3% every year.  The Moon has to be close enough to the Earth to appear larger than the Sun.                                                                    239 Draconic periods=6585.5376 days.

The first two determine a central eclipse, where the long axis of the Moon’s conic shadow reaches the Earth.  They occur every 6585.3213 days.  Eighteen years are 6570 days, and 4 leap years, or 5, make the period between successive eclipses in a family 18 years and 10.32 or 11.32 days.  The third of a day is important, because it shifts the path of the eclipse about a third of the way west around the world. This eclipse was seen in South America in 1994 and Australia in 2012.  It will be seen in the South Atlantic and Africa in 2030.

While the periods are almost alike, they are not exact.  There is a 0.03 day difference.  This seems minor, but over time, the Moon arrives at the node 2 hours later each cycle.  The Moon doesn’t have to be exactly at the node for a total eclipse to take place, but eventually, the Moon will arrive too late and the eclipse will not happen.

This particular Saros, 133, is an ascending node eclipse that began in 1219 and had its first total eclipse near Prague in 1544.  In the 19th century, it generated eclipses greater than 6 minutes, long for an eclipse.  In 1850, an eclipse was 6m50s, the longest this particular Saros would generate, and it occurred in the eastern tropical Pacific Ocean, north of the equator.  The last total eclipse of this family will be in 2373, and the last eclipse of the Saros will be in 2499.    Because these cycles are not perfect in their lining up, eventually the Moon will miss the node when new, and the eclipse family will die.  But at the same time, one new one will reach the node at the right time, and a new Saros will be born.  I find the workings of the Saros cycle as beautiful as the sight I saw from the Great Barrier Reef last 14 November.

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