Back in Chile it was a beautiful summery day. I had only an afternoon and a morning before heading back to Europe. News from home was that it was the coldest winter for years, and London was in chaos as a few inches of snow caused a kind of mass panic. All that was thousands of miles away and I found it hard not to feel a little bit of schadenfreude as I relaxed in the warm sun. I sat in the Plaza de Armas, enjoying the relaxed vibe. An eccentric old man sat down next to me and started chatting. It was good to practice my Spanish, and at first the conversation was quite sensible, but later it became more surreal and confusing. When I could no longer understand what he was saying, I got up and left. My trip ended badly. I got ill on my last night, and felt horrific the next morning. I felt so bad that I thought I might not make it to the airport, but after a morning doing nothing but sipping water I decided to give it a go. I threw on my pack and staggered out into the heat of the [...]

I headed to the airport at 5.30am. Only when I got there did I realise that my flight was not non-stop but would actually involve three legs, touching down in Iquique and Copiapó. I knew that between Copiapó and Santiago we’d fly over La Silla, and I wanted to look out for it. We flew over central Iquique, and I looked down nostalgically at the places I’d been a few days earlier. Then it was mostly cloudy from Iquique to Copiapó as the morning fog rolled in off the Pacific. I started dozing just after we left Copiapó, and soon fell fast asleep. Suddenly I woke, infuriated with myself because I was sure we must have passed La Silla. I looked out of the window over the incredible expanse of the Atacama, and right below me, as clear as anything, were the domes of the observatory. It was good to see them again.

We took the road towards Bolivia, which rose steeply into the Andes. I was fine at Putre, 3,500m above sea level, but started to feel the effects of the thin air as we got higher. By the time we reached the shores of Lago Chungará at 4,500m above sea level, I was feeling pretty spaced out. I staggered along the shore, struggling to remember how to operate my camera. My head felt like it was full of cotton wool, and every step was an effort. But despite this I could appreciate the spectacular scenery, with Parinacota and Pomerape volcanoes towering over the lake, their summits more than a mile above the shores. We went to Parinacota village, a hundred metres lower down but still the highest inhabited place in Chile. I bought some Bolivian-style popcorn and some sopaipillas, and felt a little bit better for eating. There was a brief rainshower and a few cracks of thunder, and I took shelter in the tiny church. A small table is tied to the wall here; legend has it that the table once got up and walked to a house, whose inhabitant then died. It’s been tethered ever since to prevent anything [...]

I went on a day trip to Parque Nacional Lauca. The journey would take me from sea level to 4,500m in just a few hours, which was certainly going to be a major mistake, more or less guaranteed to give me altitude sickness. But I wanted to see the Altiplano wilderness and this was my only way of getting to the park. So at 7am I got on the bus and we headed inland. We stopped at some places en route. The first was Poconchile, a small town not far from Arica. The cemetery there is famous for its decorated grave markings, and we stopped for a look. It reminded me a lot of the Arctic cemeteries I’d seen in Greenland a few months earlier. In both places, the graves surrounded by savage lands made the place feel like it was on the very limits of where human beings could thrive.

Just a few miles north of Arica was the border with Peru. Colectivo taxis plied the route, leaving from near where I was staying. I’d planned to spend three days in Parque Nacional Lauca, but was thwarted by arriving on a weekend and could only spend one day there, so I had time to spare and decided to spend an afternoon in Tacna. The journey was short, with half the time being taken up by border formalities. I got to Tacna in the early afternoon and with nothing particular to do, I just wandered into town. I passed through the long distance bus station, saw buses going to Cuzco, Arequipa, Lima and other places, and felt outrageously tempted to abandon my flight home and disappear into Peru for a while instead. Touts shouted destinations at me, assuming I was on my way to somewhere. But I decided to be sensible, and carried on into town, via some money changers who swapped some pesos for soles at an acceptable rate. Tacna was astonishingly different from Arica. The difference of 20 miles made an appalling difference to the lives and chances of people on one side of the border compared to the [...]

I was sad to leave Iquique, but I took a lot of good memories with me. I didn’t have much time left now before my flight home, and I still wanted to make it up to the very top of Chile. I got a bus to Arica, the northernmost town in the country. Arica wasn’t as cool as Iquique, but I still liked it a lot. It was a lot more run-down looking, with low houses sprawling over a huge area. The hostel I stayed in was quite a way out of the centre, so I walked for many miles during my few days here. The first day I was there was a Sunday, which was a shame because it meant all the travel agents were closed, and my plan to spend three days in Parque Nacional Lauca was impossible. So instead I wandered around the city, eventually finding my way up El Morro, a huge headland which towers over the centre. I got there as the sun was setting, and climbed up it for some amazing views of the Pacific sunset. In the other direction, looking east I could see two giant snow-capped Andean peaks, so far away they [...]

I got a bus to Iquique. It was a great journey through the desert to Antofagasta, and then up the coast. A stunning moonrise over the Andes felt like a sign that this was a good direction to be heading in. And Iquique was fantastic. The weather was awesome, the setting of the city between the desert mountains and the Pacific was incredible, the place I stayed was great, the people I met were fun, and I was in a great mood. It was New Year’s Eve, and I had a few things to sort out. I needed to buy a flight from Arica to Santiago, if I was going to make it up there and still get back in time for my flight home; I needed a new bag because mine was falling apart; and I needed an FC Iquique football top. I had a great Spanish day and accomplished all my tasks with a minimum of misunderstanding. My errands run, I went for a walk on the beach. I kept on getting into random conversations with friendly locals – someone from Santiago visiting the north for the first time, and enjoying the weather, a local who told me [...]

I’d liked El Tatio the last time I was here, four years earlier. The geothermal activity was impressive and the Altiplano scenery around it was staggering. This time I didn’t like it so much. The weather was pretty bad, with thick clouds drifting over the place when we arrived. On my first trip it had been savagely cold; it wasn’t so bad this time, but the clouds really made it look much less impressive. So I walked around the geysers, thinking I should probably have gone somewhere else instead of returning here. The 4,300m altitude and a slight lack of caffeine worsened my mood. But suddenly, startlingly, just as we were leaving, the clouds dispersed. Within a couple of minutes, the Altiplano had emerged from the gloom, and the sun shone on the wisps of steam from the declining geysers, which only erupt for a couple of hours after sunrise. We drove back to San Pedro, via Machuca, where a white adobe church shines brightly under the Atacama sun, and where locals sell handicrafts and food. Last time I’d been here, we’d had a puncture and a long wait to change the tyre. I’d been suffering with the altitude and [...]

I headed back to San Pedro. The scenery here was really mind-blowing, with the horizon fringed by giant volcanoes and in the foreground, the wild rock formations of the Valle de la Luna. Sometimes these volcanoes erupt; Lascar had erupted only a few years earlier, and Putana was smoking. I hoped that one day I’d be able to come here and see an eruption. In the evening I cycled out to the Valle de la Muerte, much closer to San Pedro than the Valle de la Luna. I stood on a hilltop looking out over the surroundings, as a strong evening wind blew down the valley. Night fell, and I cycled back into town. It had been a tiring day, and in normal circumstances I might have slept late the next morning. But I had to be up at 3.30am, because I would be returning to El Tatio.

I’d been to San Pedro before. It’s nice enough despite being amazingly touristy. All backpackers in Chile come here at some point on their journeys, and I was no different. I wanted to see some of the desert sights here again before pushing on further north. I’d cycled in the desert last time, and I decided to do the same again now. I don’t really like riding bikes that aren’t mine, but the flat-pedalled, slightly too small machine that I hired would suffice for a few tens of miles anyway. I headed out into the desert. I cycled to the Valle de la Luna. Most people come here at sunset; I arrived in the powerful heat of midday. The advantage was that I had the place entirely to myself; the disadvantage was sunburn so bad that it was visible for weeks. But that would only affect me later. On the day, I enjoyed it. I walked down some canyons, up some rock formations, and over some sand dunes. I spent a while in the silent desert setting up my camera to take photos of me cycling by. And eventually I reached Las Tres Marias, a strange rock formation quite a [...]

I was heading for San Pedro de Atacama. I had a few hours to kill before the bus left, and I didn’t feel too keen to spend them in La Serena. I wanted to go to Vicuña, a village nearby, but the buses there didn’t seem to follow any timetable. I decided that if one came in the next 15 minutes, I’d go. 10 minutes later, one came into the station, so I got on and headed out. An hour later I was in peaceful Vicuña, where the pace of life seemed very slow. It was a hot, hot day. I sat in the main square for a little while, watching things happen. A small child drove by in a powerful-looking kart – it must have been a great Christmas for him. It was heading towards midday, and the sun was beating down fiercely. I foolishly decided I fancied a walk up into the hills, bought myself an ice cream and some water, and headed out of town on a path leading to a viewpoint. It was thirsty work, but it didn’t take me very long to get up to a nice viewpoint. I could see here that Vicuña was [...]

I’d probably not have minded leaving La Serena on Boxing Day, but buses weren’t running so we had another relaxing day. At nightfall I went out onto the beach, deserted now after a busy day, and watched the sea rolling in for a while. The lights of Coquimbo shone down the coast, but I didn’t feel a great urge to go there. I wanted to head up to the far north, to places I didn’t go to on my last trip. Not feeling the La Serena vibe, I took experimental photos on the dark beach and then packed up ready to leave early the next morning.

Too soon, it was time to leave La Silla. Our observing run had been very successful, and we had enjoyed the place a lot. Now it was time to relax for a few days. It was Christmas, and we spent a couple of days in a small cottage by the beach in La Serena. I wasn’t sure if I liked La Serena that much. The town was pleasant enough but very quiet, and the beach was a long walk away from the centre. And although I enjoyed relaxing for a couple of days, I felt very impatient to get travelling to more interesting parts. Christmas day was hot and sunny. We had gone to a supermarket the day before but not found very much that we could make a traditional British Christmas dinner out of, especially with the limitations imposed by our cottage, which had hobs but no oven. So we had pancakes for breakfast and a strange potato-egg-vegetable fry up for lunch. Then we walked on the beach, which seemed very weird. I’m not sure I’ll ever get used to Christmas Day not being dark and cold.

The nights passed. We lost half of one due to technical problems, but we were a night up thanks to the earlier “technical” night, so we weren’t unhappy. The observations ran smoothly and I had plenty of time during our long hours tracking each object to go out and look at the sky. We didn’t have the mountain top entirely to ourselves. Apart from other astronomers and staff, we also saw vizcachas, Andean foxes, and donkeys rambling around the arid slopes. In the night, the only difficulty about taking long exposures of the stars spinning overhead was that I kept hearing noises of animal movements in the dark, and I was never sure what was actually there. So I’d go to remote parts of the observatory, set the camera going and then head back to the comfort of the control room, the kitchen, or the pool table, where each morning we would continue an epic series of games. One of them was slightly disrupted by a magnitude 5.5 earthquake, which I still maintain led to my narrow 39-38 defeat in the series.

In times past, the telescope control rooms were in the telescope domes, and observers would drive out each night and spent the hours of darkness ensconced in the dome. But in recent years they’ve moved all the major telescope controls into one room. It’s conveniently close to the kitchen so getting a midnight meal is easy, but it feels strange to be so far from the actual telescope. But we took a trip out there with our day technician, Paul, one evening when he was checking things over. We looked in on the 2.2m telescope and the 3.6m telescope while we were up there, and then walked back via the spectacular views from the 15m disused Swedish radio telescope. We spent our nights in the control room. In our temporary office in the same building, there was a spectacularly good coffee machine which dispensed awesome espressos at the touch of a button. The first night we were there I pressed that button 15 times, and by dawn I felt slightly unusual. In subsequent nights I kept my button presses to single figures. The only thing I seriously didn’t like about the control room was its bizarre cuckoo clock, which chimed [...]

Our run started early, in the end. A whole night was scheduled for technical work which ended up being finished early, so we were let at the NTT controls a night ahead of plan. This was a bonus, and we set to work, observing luminous stars in our galaxy and two others a few tens of thousands of light years away. I had time during the night to set up some star trail shots. The sky was stunningly clear, even if the humidity stayed just a little bit too high for conditions to be absolutely perfect. The unfamiliar southern stars were amazingly bright, and the arc of the Milky Way stretched right across the sky from horizon to horizon.

We got a bus to La Serena, spent a night there and then headed up to the observatory at La Silla. This was the first major observatory built in the southern hemisphere, and the list of incredible discoveries made here is long and impressive. But ESO’s main observatory these days is at Paranal, a few hundred miles further north. The atmosphere at La Silla is one of faded glory and a place whose best years are behind it. Most of the telescope domes are now unused. But the telescopes that still run are still among the best in the world, and we had five nights on the largest of them, the 3.6m New Technology Telescope. But because of the transport schedule, we had to arrive at the observatory three nights before our run started. So we had plenty of time to appreciate the incredible scenery up here on the southern fringes of the Atacama desert. The food was awesome, we made extensive use of the ice cream machine, we watched condors hover over the desert, and I discovered the best coffee machine in the world. All was good.

South America, to me, was hallowed ground of a kind. It was the last inhabited continent that I visited, and my first trip there was a long, epic voyage, which I’d planned for years and that will probably always be my greatest travel experience. So in a way I was wary about going back a second time. It could never match up to the times I’d had before. I was going back for work. We had some time on the telescopes of La Silla, and my presence was required as a relatively experienced observer to make sure nothing went terribly wrong. Our run was just before Christmas, so I left behind a chilly London, sat on a plane for 15 hours, and then emerged into a hot, sunny Santiago. It was fantastic to be back. I’d liked Santiago from the moment I first arrived here, on a night train from Temuco in December 2005. This time we stayed in the fantastic ESO guesthouse, in the wealthy suburb of Las Condes, and the day we arrived was the day of the 2009 presidential election. The election meant that everything was closed, and we had a look round the quiet streets of [...]