The Atacama Desert and Astronomical Thoughts....

The Atacama Desert of northern Chile is reputedly the driest place on earth. Many people living in this area have never seen rain. We docked at Arica and drove through the desert to visit the native village of Codpa. Arica just lost its “driest spot in the world” honor to another place in the Atacama because they recently had a few drops of rain. The annual rainfall is .4 mm (.016 inches). It’s a relatively narrow desert, however. We drove about 70 miles from the coast and had already passed into the pre-Andean region, where there are actually small plants and cacti. In the center of the desert, there is NO LIFE. NASA sent the Mars Rovers here to test them and they found NO LIFE!

The desert does have several fertile valleys, however, where small rivers from the Andes head toward the sea. Most dry up before they reach the sea, but they do provide some areas where modest amounts of water enable habitation. Pictures 1 and 2 show a couple of these valleys. The 3^rd picture shows a “field” of rock cairns. Long ago, nomads and shepherds would drive animals to the sea from the Andes and would leave cairns to mark their route home. Today these mark tourist routes through the desert. We were actually traveling the Pan-American Highway through the desert—a good 2-lane road.

The Atacama is a high dessert. At one point we were approximately 8500 feet above sea level. The cactus in picture 4 is a Candelabra Cactus and only grows above 8000 feet. While it looks vaguely related to our saguaro cactus, it grows much higher—the saguaro tops out at about 4500 feet.

At Codpa we were on the eastern edge of the desert. Picture 5 shows the river that enables people to live there, along with the canal to the left that provides some irrigation. Picture 6 shows the interior of their church. Note the holes in the roof—not much rain here!!!

Back on the ship, we noticed a flock (herd? Pod?) of the jellyfish shown in picture 7—quite lovely creatures.

I mentioned in an earlier post that we have been having astronomy lectures. It’s hard to get your head around numbers such as the number of galaxies, the widths of galaxies and the distances from us—how do you measure billions of light years? Today we had an entire lecture on black holes. We went in determined to understand what a black hole is and what goes on inside it. We came away somewhat smarter about what it is, but still don’t know what goes on inside. But we’re in good company. Astronomers don’t know what goes on inside. There’s a constant amount of energy in the universe and what goes in can’t just disappear—it has to come out somewhere. Some astronomers are starting to throw out “white holes” to explain how it gets out. Time travel even gets raised as a possibility.  “Long, long ago, in a galaxy far, far away….”