Saturday, April 14, 2012
Life on Mars Found by Viking? Maybe, Maybe not - the science debate continues ...
Vikings 1 and 2 were sent to the surface of Mars in 1976 to search for microbial life. The landing spacecraft conducted biological experiments designed to detect life in the Martian soil (if it existed) and the results, nearly four decades later, remains in debate, [National Geographic].
The idea was that if the soil contained microbes, the life-forms would metabolize the nutrients and release either radioactive carbon dioxide or methane gas, which could be measured by a radiation detector on the probe. Science teams have analyized the data again and again. But as the late Carl Sagan once popularized, "Extraordinary claims require extraordinary evidence".
debate has continued as to the true results of the Viking biological science experiments. Subsequent NASA surface missions have not included biological experiments to answer the questions, instead the NASA focus has been "to follow the water" as the primary building block to potential microbial life. Mars meteor analysis continues to be debated as well.
While not specifically designed to look for Mars life signs, the Mars Science Laboratory Curiosity may provide the best chance in this decade to do the ground truth search to determine of life may have evolved on the Red Planet. If the mission goes well, surface exploration will begin in late summer 2012.
Many scientists believe that either past or present microbial life will be found on the surface of Mars prior to 2020. The United States, Europe, Russia, China and India will continue to dedicate billions of dollars in the quest to find the answer. Each of the five nations have independent or joint missions to Mars over the next eight years underway or in various stages of planning.