Will unmanned robotic missions be able to detect weird microscopic life-forms they are not programmed to recognize that
might be lurking below the surface of Mars, or beneath the murky seas of Jupiter's jumbo moon, Europa?
The answer to this question is at the core of one of the greatest of the ongoing debates in space exploration: the question of man vs. unmanned robotic missions.
NASA currently operates more than 50 robotic spacecraft that are studying Earth and reaching throughout the solar system, from Mercury to Pluto and beyond. Another 40 unmanned NASA missions are in development, and space agencies in Europe, Russia, Japan, India and China are running or building their own robotic craft.
What is not commonly known however is that many of NASA's leading scientists also champion human exploration as a worthy goal in its own right and as a critically important part of space science in the 21st century.
In a past issue of Scientific American Jim Bell, an astronomer and planetary scientist at Cornell University, and author of “Postcards from Mars,” notes that “…you might think that researchers like me who are involved in robotic space exploration would dismiss astronaut missions as costly and unnecessary.”
But he then he goes on, “Although astronaut missions are much more expensive and risky than robotic craft, they are absolutely critical to the success of our exploration program."
The heart of the debate is this: robotic machines will only do what they are programmed to do; they are not programmed to detect weirdness: the unimaginable, the unknown, the strange non-carbon life that we may have encountered on Mars, for example with the two Viking vehicles, in 1976. Each carried equipment for sampling the Martian soil and miniature chemistry laboratories to test the samples for signs of life.The results these automated labs radioed back to Earth were enigmatic: the chemical reactions from the Martian soil were strange, unlike anything seen on Earth. But they were also unlike any reactions that living organisms would produce.
Ben Bova, the acclaimed science-fiction author of Titan and The Aftermath, his most recent novels in is his ongoing series about the expansion of the human race throughout the Solar System, points out in an interview that most scientists examining the Viking results, reluctantly concluded that was lifeless: "But the fact is that the landers were equipped only to detect signs of Earth-type life. The chemical reactions observed could have been the results of Martian life. They certainly were not ordinary inorganic chemistry."
The debate over the meaning of the Viking results, Bova concludes, is still unsettled, more than 30 years later. But a human biologist or biochemist could have learned a lot more and settled the matter, one way or the other, within a few hours.
What are we looking for, exactly, when we search for alien life? That's the cosmic question pondered in a new report from the National Research Council, The Limits of Organic Life in Planetary Systems. For more than five years, a committee of scientists tried to imagine what life-as-we-don't-know-it might be like. Their conclusion: Life may exist in non-carbon forms completely unlike anything we see on Earth.
The human-versus-machine debate is a false choice. Robotic unmanned spacecraft are directed by human beings on Earth. Unless disabled by fierce sandstorms, our rovers are in constant realtime communication with their masters at the Jet Propulsion Laboratory, as will the New Horizons spacecraft now heading for Pluto with human monitors watching over it. Exploration of the distant gas giants, Saturn and Jupiter, will be performed by next-generation robotic machines like DepthX, a mushroom-shaped machine, an underwater hydrobot that 'thinks' for itself, which is being developed to search for life on one of Jupiter's moons.
Posted by Casey Kazan.
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