Hightech in the Desert: Observatorio Paranal

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The Atacama Desert is the driest place on earth. For that reason it has been chosen as a site for various space telescopes. Astronomers and Astrophysicists value the dry atmosphere and the little amount of diffused light due to the remotenes because it gives them a much clearer view into the sky.
It makes visits to the telescopes quite difficult though. I had arranged a visit to the telescope of the European Southern Observatories (ESO), the Very Large Telescope (VLT). This prestigious facility was built during the nineties on top of Cerro Paranal as a cooperative project between different European countries. It still remains to be the most powerful telescope today. I had once taken part in a summer school where we got to know the telescope's basic features and discused research projects done based on its observational data.
The contact person had given me a rough driving directions and a time for my guided tour. So I had to rent a car in Antofagasta and make my way into the desert. I tell you the telescope is very remote... it's about 120km from Antofagasta including about 80km on a gradually worsening desert track.
When I was driving more than two hours right into the desert without knowing if I had lost direction and with just two liters of drinking water (when I realized this it was by far to late to go back). I felt just adventurous at first. Later on I felt quite daring, and when I couldn't see any telescope after more than two hour of just dusty and sandy windswept hills and a track full of potholes I felt stupid and scared.
I hadn't messured the kilometers too exactly, something I now know is very advisable in the desert. The tank was still quite full and so I gave myself 15km more. What I found was a landing strip in a broad valley, a road, suddenly in excellent condition winding up the hillside, and a stone-built sign reading: ESO, Observatorio Paranal. Yeah, I found it!
Driving up the hill sign said things like "switch to parking light beyond this point", and "no lights at all beyond this point". From the hilltop I could see the research facility lie in front of me. The maintainance buildings and the scientists quarters in a valley below me and further beyond Cerro Paranal with the telescope on its flattened top. Or rather the telescopes since there are altogether four big and several small telescopes.
Later on when I had my guided tour I saw a short documentary about the construction of the telescope. What an extraordinary amount of efford had been necessary to build it! The whole top of Cerro Paranal was blasted away to gain enough room and a flat surface. And the four principal mirrors! They all have a diameter of more than eight meters. Imagine the task of bringing such a mirror from Germany where they where manufactured to such a remote and inaccessible site! After shiping them to Antofagasta they were brought into the desert on flat-bed trucks, right on the same track I had just used. To make sure they would survive this aprt of the journey they built a steel replica, equiped it with sensors and did a test delivery before they transported the real ones. The stell replica can still be seen next to the entrance today (see the withe thing next to the gate keepers house on the second picture).
Later on we went to the top of Cerro Paranal and I had the chance to see one of the four telescopes from the inside. Really hightech, really impressive! And when this huge thing turns or inclines you hear almost nothing...
In the control room where the scientist work, usually at night, I learned that the scientists themselfs do not angle the telescope. Instead there are several engineers and other specialised employees that control all the machinery.
I didn't really count on it but I had hoped perhaps to be allowed to see one of those wounderous machines working in the evening but since the viewing hours are precious time and have to be applied for long before I could not.
Still I wanted to see the setting in the night. I had the rental car for twenty four hours anyway and wanted to stay overnight. I had to leave the facility and had to promise to keep out the light, but otherwise I was allowed to stay. Sunset and sunrise are just beautiful, there's a nice view over the pacific ocean, witch is quite close and usually covered by a low layer of clouds. This is one of the secrets of this site. The air, warmed up over the desert is cooled down over the ocean, sinks, and thus keep the humid air from the sea down and away from the telescopes. The air is so clear and dry that the soutern sky, already ritcher in stars than in the northern hemisphere anyway, brightens in full beauty. Besides the usual star pictures you can see the center of the milkyway, a huge part of the milkyway's star clouds, and two other star clouds, outside the milkyway, the Large and the Small Magellanic Cloud (see the long exposure foto). Used to those colorful Hubble images it was the first time I ever saw a star cloud with my bare eye.

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Photos

Two of the Four "Big Eyes"
Here I stiched two pictures to one panoramic so you can fully appreciate the incredibly clear dark blue sky over the UFO-like hightech construction of the telescopes.

Observatorio Paranal
I was really happy to arrive here after the long drive through the desert.

Espejo Grande
With more than eight meters diameter the VLT features the largest concave mirrors in the world.

Big and Small
Besides the four big telescopes there are several small ones.

The Inside
Fully rotatable and tiltable, hidden away from the desert sun inside its slightly cooled housing, this is the aparatus of the telescope.

CCD Camera
Nowerdays nobody actually peeks into a telescope directly anymore. Instead several electronic sensors are used, basically huge digital cameras for different parts of the electromagnetic spectrum.

South Pole of the Southern Sky
Long exposure during the night in the desert. The image hasn't been cleaned from digital noise but you can see the soutern cross on the left, with the two pointing stars below, and a bright part of the milkyway above. More to the right you see traces of the big and the small Magellanean cloud.