The Search for Life

             There are two types of searches for extra-terrestrial life. The first type is the direct search, or the search for life itself. A good example of the direct search for extra-terrestrial life is a recent mission that analyzed photographs of Martian terrain (Conrad, 2007). This search led to the discovery that water had existed on Mars for a long time, and in great quantity (Conrad, 2007). Many of the rocks that were analyzed were bleached (Conrad, 2007). Scientists knew that this process must have been caused by some kind of liquid, the most likely fluid being water (Conrad, 2007). The bleaching process is extremely slow, so scientists hypothesized that water must have existed on Mars for a long time (Conrad, 2007). This is a direct search for extra-terrestrial life. According to a CBC News article, Canadians have recently made a contribution to the search for extra-terrestrial life. In 2005, Canadians designed a weather station that would analyze the geology and climate of the planet Mars, and that might have a significant impact on scientists’ knowledge of the planet (CBC News, 2005). The mission, of course, is part of the direct search for extra-terrestrial life (CBC News, 2005).

          The indirect search for extra-terrestrial life is completely different. The indirect search includes detecting laser signals, or searching for radioactivity (“Extraterrestrial life”, 2007; CNN, 2003). This search takes into account that if there existed another intelligent civilization in the galaxy, it would try to communicate with other civilizations, therefore sending out laser signals, or signals of some other form (“Extraterrestrial life, 2007”; CNN, 2003). In the process of analyzing signals through extremely powerful telescopes, scientists have identified 150 signals that could have been generated by other intelligent civilizations (CNN, 2003). These signals that the scientists viewed as possibly coming from other civilizations were ones that had to be particularly strong, and observed in the same area more than once (CNN, 2003). Nothing, CNN reported in 2003, had been found yet of interest. SETI, a body of scientists searching for intelligent extra-terrestrial life, was behind this project (CNN, 2003). SETI chief Dan Wertheimer said at the time that he believed that in the next 100 years, scientists would discover several extra-terrestrial civilizations (CNN, 2003). SETI has been, for a long time, one of the most prominent organizations involved in the search for extra-terrestrial life (“SETI”, 2007). This organization rose to considerable fame in the late 1970s when a SETI volunteer, Jerry Ehman, discovered a startlingly strong signal while searching with his telescope (“SETI”, 2007). Ehman promptly wrote the word ‘wow’ next to his finding, and ever since, the strong signal has been known as the ‘Wow Signal’ (“SETI”, 2007). Considered the most likely candidate to be from an alien source, it has not been detected ever since (“SETI”, 2007).