South America was blessed with a wonderful total solar eclipse July 2nd, 2019. This was my third eclipse. My first was in Aruba in 1998. What I remember most is that I had only seen old-fashioned photos of a diffuse hazy corona, so I had no idea what it would really look like. In the airport on arrival, there was a beach towel for sale in a souvenir shop that showed the corona as a many streamers coming out from the center and I thought, well that is a fanciful way of drawing it. Despite rain an hour before totality, we had a crystal-clear sky for the main event, and to my surprise, it looked like infinite pearly white streamers coming out from the Moon-covered Sun, just like the beach towel. After all the books and journals I read beforehand, it was ironic that a beach towel was the most accurate depiction. It also had some nice prominences that I described as pink-red-yellow, and the corona was flattened, as is typical near a solar minimum. And we got to share the view on a hill with a number of Aruban families who were also seeing it for the first time.
My second eclipse was in Wyoming in 2017. We were in the middle of a barren landscape on a small hill with a 360-degree view at least 50 miles in every direction. I expected to see the shadow coming towards me, but the truth is that it just happened instantaneously. But a series of our photos shows the shadow rose up from the horizon, so that the eclipse came up over us instead of towards us. That eclipse was most strikingly strange. You really felt like you were in a science fiction movie with a special effect. The Moon was black, the sky was very dark blue, and the Sun was surrounded by a white fringe, as if the sky were being sucked into a black hole. It was so striking that in our group of 15, no one cheered or high-fived. We were silent except for the wailing two-year old who got spooked and someone who said at the end, “I need to process this.” There was a great prominence that I described as electric pink with one area inside of it that was brighter and more orange.
For this 2019 eclipse, we made reservations a little late, 18 months in advance. One of the most popular locations, Vicuña, Chile, was completely sold out, as were all the local offerings on Airbnb. We ended up going onto the Spanish version of Airbnb and found a number of offerings in La Serena. First, let me give you a little background. La Serena in on the Chilean coast, and was likely to have evening clouds right in the direction of the eclipse. The Elqui Valley, inland, had better weather predictions, but you had to be careful not to miss the low eclipsed Sun behind a mountain given the deep valleys. Vicuña, located in the Elqui Valley, was known to be sufficiently open and was the target of many eclipse expeditions. The Andes Mountains themselves were certain to be cloudy. Beyond the Andes in Argentina, was high and likely to be dry. Bella Vista is a small, rugged place that some targeted, although it is much more complicated to get to than the Chilean locations.
Our plan was to fly in to Santiago June 30, drive five hours to La Serena, and drive to Vicuña very early the morning of the eclipse. Spend the day, drive back that night, and drive back to Santiago that next day for a flight home. We were quite concerned about traffic, especially noting the tie-ups in Wyoming after the eclipse on the standard routes, so we were not sure this was feasible, but it became the plan nonetheless. We landed in Santiago no problem and got our rental car from Mitta, Hertz’s Chilean partner. Our friends were told by Avis that they simply did not have any cars left. Luckily a relative’s friend owned a car rental company, and they got a car. A bus would have been the alternative. Other friends tried to fly down from Calama, Chile, but the airline had overbooked the seats. They did take a bus.
We drove to La Serena. We were amazed at the wonderful preparation that the Chilean government did for the eclipse in all sorts of ways: managing traffic, portable bathrooms, publicity, public viewing sites, appropriate safety warnings, and monitoring without intrusion. To our pleasant surprise, we had rented a luxurious triplex apartment on the top floors of a beach resort condominium with three balconies facing the ocean. Its Airbnb description did not do it justice, and the price was extremely reasonable. The first night was punctuated by a green flash on the water as the Sun set. As the Sun sunk below the horizon, at first we saw what was likely just a contrast effect: the rim of the Sun looked greenish due to the disappearance of the brighter orange bulk of the Sun. But in the last second or two, an emerald beacon shone out, clearly not just contrast and witnessed by two of us.
Long-term weather predictions in Chile were not that great, with 60% clear skies in the best areas, and really higher risk because the Sun would only be 13 degrees above the horizon during totality right around 5pm when low clouds were likely to form. A week beforehand, the forecast looked good, but four days out a pair of low pressure systems threatened to cover the entire eclipse path with thick clouds. As the day approached, the problematic system moved north by hundreds of miles, leaving a cloudless path from the Chilean coast through Argentina.
The night before the eclipse we had to make a decision. Go with the plan to drive to Vicuña overnight, getting clearer, lower humidity skies with less risk of a last-minute cloud developing, but risking getting stuck somewhere due to crowding with no view of the eclipse, and then probably spending the entire night driving back to La Serena, only to leave immediately to catch our flight in Santiago that next night. Or just stay in La Serena, benefiting from a clear view down to the horizon, seeing the solar reflection off the water into the distance, and avoiding feared traffic, but ensuring hazier skies and risking a last minute cloud blocking the view. We decided to stay put.
The morning of the eclipse was cloudy, rendering all previous predictions suspect. The new prediction said clear by 9am, and it was true, but we had a hard time trusting predictions any more. It was hazy, but it cleared as the day went on. We next had to decide among the public beach, the resort beach, or the balconies. We had enough of our own crowd that we did not feel lonely, and we decided to get the best view of the distant horizon from the balconies.
During the day we viewed the Sun through a Quark H-alpha filter to see if there would be any prominences. There was a moderately sized faint one in view. (Checking for prominences before an eclipse is debatable, like finding out the sex of a baby before delivery.) As the 4:38pm totality approached, the beach became eerily dim, not at all like sunset. I guess the differences were that the Sun was still relatively white instead of orange, and the Sun was still relatively high in the sky. The seabirds went crazy, flying around in large loops off the shore and up the thermals on the condos. Chilean helicopters patrolled the beach from the air, but they cleared the sky for totality. One of us took a time-lapse photo of impending totality.
You cannot watch everything at once as totality approaches. I saw the Sun going into the full eclipse and the last bits of bright light disappearing from one side. I noted the striking black Moon surrounded by numerous pearly white streamers of the corona, and the very dark blue sky all around. I did not look for planets or stars. My 10×42 binoculars and 92mm refractor showed the corona in more detail. As the eclipse progressed, a large prominence appeared from the side. I would say the color was electric pink, and very different from the H-alpha color we normally view them in. I grabbed my DSLR camera, took three quick shots in a 300mm lens using the settings I had previously prepared, and forced myself to put the camera down (see the attached image). In the last seconds of totality, the Sun brightened on one side. It was a bright white light, but not nearly as bright as the true photosphere about to ruin our views. The instant the photosphere peaked out, we declared no more looking through optical equipment and stopped looking at the Sun. The eerie dimness gave way to a bright Sun.
This was the same crowd who went to Wyoming, and we were less stunned this time. We even let out some cheers along with the crowd on the beach.
We later looked at the time-lapse video of the eclipse start (https://youtu.be/NFyuANV0S7A). It shows the darkness rising up from the horizon, which we also saw in Wyoming. It also shows the solar reflection on the water disappearing towards us; it might just be the whole thing dimming at once because the closest reflection is the brightest, but it seems that the most distance reflections did disappear first, as if the shadow had approached us. It also shows Venus clearly in view on the lower left, although I did not notice it during the eclipse. I wish I had a video of the end of the eclipse to see if the reflections reappeared first in the distant reflections.
The different views of prominences for the different eclipses are fascinating to me because I frequently view them in monochromatic H-alpha red. The 1998 eclipse seemed to have some yellow component; I described the color as red-pink-yellow in my journal. The 2017 eclipse is a more recent memory, and I clearly saw the electric pink but with a more orange region in the middle. This 2019 prominence had no orange or yellow to my eyes. I suspect the energy of the prominence determines the color. The H-alpha view in 2019 showed only a faint prominence, whereas the other two were probably more energetic. I cannot tell if the color actually changes or if it just appears more orange or yellow as it becomes brighter. In monochromatic H-alpha light, bright solar flares look yellowish even though you are clearly only seeing one frequency of light, so it may be the eye or perception and not real color.
The drive to Santiago and flight home were easy; we stopped for some local sightseeing on the way. The preparation by the Chilean government bodes very well for the next eclipse in 2020. We are already way late in planning that one.