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Solar Total Eclipse, 02 July 2019

Another eclipse, another country! Except that this was a return to one of my favourites – Chile. Following a 90-minute delay because of an electrical fault, the fourteen-hour flight to Santiago was uneventful. Surprisingly, the delay was not totally unwelcome as it reduced the waiting time for the transfer to our hotel – a mere six hours, as we arrived considerably in advance of the rest of the group. There wasn’t much in the arrivals hall at Santiago Airport, but there was a café (Le Fournil), at which we made a couple of coffees and beers last four hours!

In Santiago, we started with an orientation tour of the city, in rush hour on a Friday night when every local was trying to get home to see Chile play Colombia at football. (During the match, Chile had two goals disallowed.) We watched the match in a seafood restaurant, surrounded by television screens. We were served ceviche – raw fish cured in lemon juice - followed by a plate of several different fish fillets. The Chileans are not big on vegetables and the fish was accompanied by approximately four chips and a pile of grated carrot.

The following day, during a visit to a couple of vineyards, we were served a huge hunk of deliciously slow-cooked beef atop a mountain of buttered mash. In general, the food during our stay was very good and plentiful. The wine was also very good, especially that made from a grape which was thought to be extinct worldwide until it was discovered masquerading as the Carménère (a cabernet grape) in Chile.

Waking up at 3.00am due to jet lag enabled an exploration of the wonders of Chilean night-time television. Programmes such as Bob El Constructor and Bombero Sam loomed large – dubbed into Spanish of course.


Figure 1. Austral beer.

The second day included a day out to the seaside, the port of Valparaiso, a little old town that has grown randomly up the sides of the steep hills surrounding a natural harbour. Back at the hotel, after a couple of Austral beers (brewed in Punta Arenas; see figure 1) we realised that the sky was clear and we might be able to see some delights of the southern sky. But from the middle of a city? Strangely enough we did! We crossed a busy main road next to the hotel and wandered in to adjacent parkland, where our surroundings were still very brightly lit. We climbed on to a steep bridge that spanned an even bigger dual carriageway: half way across we could see most of the sky but there were still many street lights. Undeterred we shaded our eyes and looked up. First, we saw Jupiter shining next to Antares and, after some straining, most of the outline of Scorpius. At higher altitudes we saw the unmistakeable pointers (α and β Centauri) and the Southern Cross.

Back at the hotel, I realised it was results day at the University of Central Lancashire where I had been studying for a degree in Astrophysics for the last 10 years. I had been awarded a first-class honours degree. Champagne all round – Chilean of course!

Day 3 brought a brief flight to La Serena, the base for our eclipse viewing. Here we met with the rest of our party on different itineraries, and also with other groups such as Sky & Telescope, Travel Quest and UCLA Alumni. The hotel in La Serena was very comfortable and was the venue for the mandatory eclipse briefing, with final event timings and other details. Alas, the hotel could not cope with the number of groups resident as a result of which our evening meal extended over many hours. After the meal, given the very close proximity of the beach, we thought that a little impromptu night sky observing might be possible, however there was too much ambient light.

The next day, 02 July, was eclipse day. The observing site was some 7 km north of the town of Vicuña, reached from La Serena via Route 41, across the foothills of the Andes into the Atacama Desert (see figure 2). We left La Serena by coach early in the morning because of dire warnings about the traffic jams that would be caused by the 80,000 visitors in the area estimated to be travelling to see the eclipse. In the event, there turned out to be negligible traffic and the journey to the observing site was problem-free. The observing site itself was a high mountain ranch-type area, which we shared with a couple of other small groups. Across a small valley there was a large group of Yale University alumni with their own tent city. Two observatories were visible from the site to the south: Cerro Tololo Inter-American Observatory (CTIO), some 25 km away and Gemini South, some 32 km distant. The site of the new Large Synoptic Survey Telescope (due to open in 2024), not far from Gemini South, was also visible.

Locations.png Figure 2. Location of the observing site and visible observatories.

I am used to being fed and watered on organised eclipse trips, but this was the first time that I’ve enjoyed a three-course, silver service dinner atop a mountain in the Atacama Desert!

The eclipse itself was fantastic, with not a cloud in the sky. Greatest eclipse occurred at 16:39:52 local time (20:39:52 UT), and the Sun was therefore at a relatively low altitude of 13°. We therefore expected a good display of shadow bands but, although there were some faint lines immediately after third contact, we were disappointed. The corona was much as predicted, fairly tight, befitting a solar minimum. I took the usual temperature readings in the shade throughout the eclipse; this is a bit of fun and not scientifically important. (See figure 3 for my results.) The readings show clearly a dip just after totality, the temperature lagging the obscuration of the Sun, as expected.

20190702_SE_temperature_in_the_shade.jpg Figure 3. Temperature in the shade.

I, together with several of the party, remained on site after the eclipse to explore the southern sky from a truly dark location. Highlights included Scorpius in its entirety, Jupiter and Saturn, Canopus, the Large and Small Magellanic Clouds, and dust lanes in the Milky Way.

The coach trip back to La Serena marred what was otherwise a thoroughly good day. Unfortunately, the door of the coach would not close properly and repairs occasioned a 30-minute delay to our departure. Although the journey to the observing site had been problem-free, the return journey took four hours and we arrived back at the hotel at midnight-thirty. Initially thinking that we should have returned to La Serena with those who did so immediately after the eclipse, we found that they had experienced an even longer journey of five hours and had arrived at the hotel only an hour before we! The hotel had maintained a buffet for us, but no-one was hungry at that time of the morning.

The last day of the tour included a boat trip to visit some offshore islands where we saw black footed boobies, 10 different types of cormorant, southern sea otters, dolphins (bottle-nose and southern), grey foxes and llamas. We visited Penguin Island but, unfortunately, the penguins were largely out at sea mating, although I think I may have seen one on land.

The final day dawned: fond farewells and hours waiting at airports. There was an earthquake near Los Angeles – would it affect the airport? We had a tight deadline, as we had to complete three flights in 24 hours: La Serena to Santiago, Santiago to Miami and Miami to LA. Things started well but there was a fault on the plane from Santiago to Miami and the flight was delayed by two hours. We had a three hour turn-around at Miami, so only a one-hour slot to make our connection, but we spent 90 minutes in immigration passing through the new streamlined electronic process followed by a very lengthy wait. There was just one official on duty for the 800–1000 people in line. However, a nice young lady propelled us towards the front of queue by continuously repeating "they’re elderly!" But we still missed our connection. Would there be another flight to get us to LA in time to catch the cruise liner? We proceeded to the "missed connections" desk to find that our connection had been delayed by 70 minutes so we caught it after all, and I write this aboard the MS Queen Elizabeth enjoying champagne and sea views!

Figure 4 - 6 are my images of the eclipse, all taken with a Nikon D3200 camera with a 300 mm lens at ISO 200, f/5.6.

20190702_diamond_ring_PJW.jpg Fig. 4. Diamond ring effect. 1/1600 s exposure.

20190702_corona_PJW.jpg Fig. 5. Corona. 1/30 s exposure.

20190702_chromosphere_PJW.jpg Fig 6. Chromosphere. 1/1000 s exposure.

More Information on Eclipses

See Fred Espenak's eclipse web site eclipse.gsfc.nasa.gov/eclipse.html

Paul Whiting, FRAS