I was one of eleven intrepid mountaineers attempting to climb Nevado Sajama, the highest peak in Bolivia, to observe the total solar eclipse of November 3, 1994 from it's 21,400+ summit. This would be a historic event, as we would be far higher than any other ground-based eclipse observers in history. Conditions would not be the best for optimizing our chances of a good eclipse. There would be no chance of moving our observing site if observing conditions turned bad. In fact, we would have no weather forecast or any other contact with civilization for a week before the eclipse. And there were no guarantees that we would even reach our chosen observing site on the summit. Nevertheless, the opportunity to watch the shadow approaching from perhaps hundreds of miles away across the Andes in Peru and receding over the broad high desert of the Bolivian Altiplano, and to observe the eclipse with most of the Earth's atmosphere below us, was something that this small group of adventurers couldn't pass up.
Our team consisted of three professional mountaineers/guides (two American, one Bolivian) and eight amateur mountaineers with experience ranging from 12,000 foot peaks in the United States to international high-altitude climbs. Two had astronomy backgrounds, myself as an active amateur astronomer with experience at public and private research observatories, and a young and very enthusiastic German Luftwaffe officer, Stefan, with similar experience (the only other non-US citizen on the team). Stefan and I spent a lot of time comparing each other's notes in preparation for the eclipse. The two of us and my son, Steve, were the only team members to have previously seen a total solar eclipse. Our team was an eclectic group, including a doctor, a deputy district attorney, an accountant and a bicycle mechanic. Neither the climb nor the eclipse alone lured the team members to this remote volcano in a remote country, but the combination of the two was a once-in-a-lifetime opportunity.
Flying into the airport at La Paz (Bolivia's largest city) was exciting for mountaineers, descending between peaks of the Andes towering to over 21,000 feet above the city. The airport is on a high plain at an altitude of over 13,000 feet and the city is over 12,000 feet high. Even for those that had been to altitude in the USA recently the sudden loss of oxygen had an effect that lasted for a few days. We spent several days sight-seeing with an emphasis on hikes that would help us to acclimatize to the altitude. We were in Bolivia early enough to precede the hordes of eclipse chasers that seem to invade any corner of the Earth fortunate enough to play host to this spectacle, and we found the country fascinating and the people delightful. Even as the poorest country in South America, Bolivia is a comfortable and friendly place to visit.
We were told to expect a difficult drive to our base camp on Nevado Sajama, and the small bus burdened with the supplies of a 10-day mountaineering expedition hardly seemed up to the task. Although the road we would take was an international highway and a major trade route between Bolivia and Chile, it was dirt for the entire 110 miles that we would be on. As it turned out, it was the worst road that any of these world-traveling mountaineers had been on, and the times when the top-heavy bus seemed to defy gravity as it leaned precariously on steep sections were without a doubt the most frightening parts of the whole expedition. I have rarely seen mountaineers so terrified. The bus broke down frequently, causing a rush of activity amongst the Bolivian crew -- all became mechanics, with an astonishing array of tools and spare parts stored in various parts of the bus. After a hot and dusty 10-hour drive we arrived after dark at the station where animals would be hired to transport our gear to base camp. We cooked dinner over backpacking stoves in a thatched-roof hut and slept in our tents without ever really seeing our surroundings. The next morning would have been perfect eclipse weather, crystal clear air and a spectacular view of the glacier-capped volcano we had come to climb to the east, with 19,000- to 20,000-foot volcanoes on the border with Chile to the west. It was hard for us to remember that the valley floor we slept on was at over 14,000 feet, almost the altitude of the highest peak in the 48 contiguous states back home. Discovering that we had slept surrounded by a herd of llamas helped to reinforce the exotic nature of this camp.
An experienced team of three German climbers, one of whom was an astronomer, preceded us to base camp by a few days, also preparing to climb the mountain and observe the eclipse. They had heard of our expedition and decided to try it themselves. Stefan and I spent the evenings viewing the southern sky with binoculars, since telescopes were a luxury that we could never have hauled up the mountain at those altitudes. I had never been south of the equator before and Stefan, who had spent time at an observatory in South Africa, was a very willing guide for me -- the first time in 25 years that I'd needed help finding my way around an unfamiliar sky. Observing was difficult, though, due to scattered high clouds. We didn't consider the implications of those clouds for observing the eclipse since that event was still a week away and the odds of clear skies were very high.
The climbing proved to be more tiring than expected, though not technically difficult. Because of a drought in the area for many years the glacier had receded and we were on dry ground up to almost 18,000 feet. Crampons (metal spikes attached to the soles of climbing boots) would give us good footing on the ice at higher elevations, but the loose dirt and rocks (scree) up which we had to carry 50 pound loads gave such poor footing that we were exhausted after the first day of ferrying supplies and equipment to our first high camp. I began to wonder if I should have opted for the typical tour bus eclipse trip. I had trouble with the altitude above 16,500 feet on that day, but after an extra rest day we all made it to Camp 1 at 17,600 feet, a rock outcropping just big enough for a few tents, with sheer drops on three sides. The view, looking west across the valley into Chile and Peru was spectacular. That night I got very little sleep due to altitude-induced breathing problems and was in poor shape in the morning. Behind schedule, and with the eclipse occurring the next morning, we needed to ascend a 200-foot ice wall and climb the glacier with full packs to make camp at 19,200 feet, rising shortly after midnight that night to make for the summit in time for the early-morning eclipse. I needed another day at Camp 1 before proceeding, so it was clear that I wouldn't make it to the summit for the eclipse. The camp I was at would hide the rising Sun until just before second contact, and rather than sacrifice a view of half of the sky I decided to descend to base camp with two other climbers, one of whom had suddenly developed symptoms of severe altitude sickness and needed to descend to lower altitudes immediately.
Eclipse morning dawned with considerable high clouds to the east -- the Sun was obscured. Clear weather was practically guaranteed in this part of Bolivia at that time of year, but weather records didn't help us any that morning as we climbed a ridge for the best view and hoped for the best. Once on the ridge we turned toward the mountain and were surprised that we could easily see two three-man teams trying for the summit. The others had decided to observe the eclipse from near Camp 2 at around 19,500 feet; all were suffering from the altitude. The clouds slowly thinned and we were soon able to view the partial phases as the light around us dimmed. While climbing to our observing site at around 16,000 feet, with Nevado Sajama lurking above us and the volcanoes across the valley in Chile spouting clouds of steam, a small group of guanacos (a beautifully graceful wild cousin of the llama) sprinted by just below us in the eerie light that comes from the last sliver of Sun before second contact (made stranger, I believe, by the lack of atmosphere around us). The strange light, exotic desert mountain terrain and alien-looking creatures gave me a strong sense of being on another planet -- even before totality everything looked unfamiliar. I put a wide angle (20mm) lens on my camera to photograph the approaching shadow as the clouds thinned. Photographing the extremes of the outer corona in the clear mountain air was now clearly impossible due to the high clouds. I had heard of Samuel Langley's observation of the corona for 20 minutes before and after totality when he observed an eclipse from Pike's Peak and I had hoped to occult the crescent Sun and photograph the corona outside of totality, but our high-altitude clear air advantage was wiped out by the thin cirrus.
Despite the cloud cover, we could clearly see the shadow as it descended from the peaks across the valley and rushed towards us. We watched as it engulfed the peak above us and swept across our panoramic view to the south (we were north of the centerline). The corona was beautiful despite the thin clouds and in it's light the glacier was easily visible on the mountain above us. With my plans for totality thwarted by the change in the weather I kept the 20mm lens on the camera and captured panoramas of the peak and my fellow observers in corona-light. Just before third contact I saw the chromosphere for what seemed like a very long time, followed by the most startling diamond ring that I've ever seen. The darkness above was gone, but we could still see the shadow sweep out onto the Altiplano, headed for Paraguay.
Only two members of our team made it to the summit, and they arrived shortly after third contact. The strongest climbers had become too ill and the only Gringo that made the summit had previously not even been higher than La Paz. But everyone on the team had a spectacular view of the eclipse at altitudes varying from 16,000 to 21,000 feet, with Stefan reporting that from an altitude of 19,500 feet he could see the approaching shadow seven minutes before second contact! The German party was ahead of our schedule and they were successful in observing the eclipse from the summit, claiming, I believe, the record for the highest eclipse observation for observers still in contact with the Earth. The weather turned worse after the eclipse, and we watched the rest of the team as they fought snow and fog while descending the glacier. The next two mornings were completely clear, the kind of weather we had expected for the eclipse but had not actually seen for a week. By the second day post-eclipse we were back on the bus for what turned out to be an even worse ride back to La Paz, with the unseasonably wet weather having rutted the road even more and raised the streams that we had to cross. After a 14 hour bus ride to cover 110 miles (during which we endured the continuous play of the drivers' only music tape, combining Andean music and American Disco), we arrived back in La Paz after most of the other eclipse chasers from around the world had already left for home. I've seen other eclipses and climbed other mountains, but even though I didn't reach this summit or have perfectly clear skies the trip was a great eclipse experience. And it proves that some eclipse chasers will do almost anything to get to the best observing site around.