Want to stay on top of all the space news? Follow @universetoday on TwitterSome parts of the Atacama Desert haven’t seen rain since record keeping began. Yet, somehow close to a million people eek out a living from the driest place on Earth. The desert stretches nearly 1,000 km from the southern border of Peru into Chile. It rises from a narrow coastal shelf to the near lifeless plains that dip down to the river gorges that are rich in mineral deposits from the Andes. The Atacama desert is driest at its center where you won’t see a blade of grass or cactus stump, not a lizard, nor a gnat. Studies by a group of British scientists have suggested that some river beds have been dry for 120,000 years.
The climate of the Atacama desert is brutal on the living, but it is a natural way to preserve everything. You can see the remains of most everything left behind by humans and animals. Without moisture, nothing rots. Everything turns into artifacts. Even the bodies of little children. That makes it even more shocking to realize that almost a million people make their living in this wasteland. They crowd into coastal cities, mining compounds, fishing villages, and oasis towns. Astronomers flock here to any one of the observatories that take advantage of the perfectly clear skies.
Because of its high altitude, nearly non-existent cloud cover, dry air, and lack of light pollution and radio interference from the very widely spaced cities, the Atacama desert is one of the best places in the world to conduct astronomical observations. The European Southern Observatories operates two major observatories in the desert: La Silla Observatory and the Paranal Observatory which includes the Very Large Telescope. A new radio astronomy telescope called ALMA is being built in the Llano de Chajnantor Observatory. A number of radio astronomy projects have been operating in the Chajnantor area since 1999: CBI, ASTE, ACT among others. These dry conditions are also helping scientists explain the conditions on Mars.
Residents of the Atacama desert used to have to import water by truck. It was very expensive and there was never enough water for cooking, drinking, and showers. Rain rarely falls on the Atacama’s coastline, but a dense fog known as camanchaca is abundant. The fog nourishes plants in isolated islands of vegetation that can contain a wide variety of species, from cactuses to ferns. Some residents now take advantage of the same camanchaca that their botanical neighbors have so successfully exploited. Thanks to Canada’s International Development Research Centre and the Canadian Embassy in Santiago, villagers began to gather water using an ingenious system of nets that catch the fog as it rolls over the mountains above their homes. Constructed from a very fine mesh, the nets hang vertically above a series of troughs. As the fog condenses on the nets’ surfaces, moisture drips into troughs. Pipes then carry the water down to the village. Residents can now take pride in their gardens and they can shower daily. The fog-catchers supply an average of 10,000 liters of water every day.
Living in the Atacama desert is nearly impossible, but people have been doing it for thousands of years. This region has yielded mummies from 18,000 B.C. These are the oldest mummies known to man. There are some geoglyphs there that are similar to those at Nasca, Peru. It makes you wonder what people were doing that they needed such large drawings in the soil?
Follow this link to get some more information about the Atacama desert. Here on Universe Today we have a great article about the relationship between the Atacama and the environment of Mars. Astronomy Cast offers a good episode about radio astronomy.