Many years of robotic exploration of Mars have not produced evidence of life on the Red Planet. During the next twenty years, NASA will conduct several missions to try to determine whether life ever arose on Mars. NASA’s Mars Science Laboratory mission Curiosity rover, will launch in late 2011 and land on Mars in August 2012. The search will focus on places where there may be liquid water at sources of geothermal energy. There is great expectation that there may be Martian microbial life, but it would really be surprising to find multicellular organisms. Some scientists think that life on Earth may have had its start from microorganisms that traveled on rocks ejected from Mars after meteorite impacts. If life is found on Mars, DNA analysis will be used to identify similarities to Earth organisms.
The search for intelligent life has been a dream of science fiction. The Star Trek television series started each episode with the prologue “Space: the final frontier. These are the voyages of the starship Enterprise. Its five-year mission: to explore strange new worlds, to seek out new life and new civilizations, to boldly go where no man has gone before.”
Establishing a technologically advanced society has a great number of special requirements. We have been able to achieve this because we live in an oxygen atmosphere where we can make fire that makes it possible to smelt metals. Our manual dexterity enables us to manipulate objects easily and to build tools. Had we been relegated to the realm of the sea with flippers instead of hands with opposable thumbs, even with all our brain power we would not have been able to build the technology to send a probe to another world. The Neanderthals who preceded us were able to use fire for cooking and for warmth, but in the 250,000 years that they were on Earth they did not advance beyond the stone age. Modern humans have existed for about 60,000 years, and civilizations were only established 10,000 years ago. In the last 250 years, our industrialization has managed to pollute the atmosphere to the point that we may trigger a global warming event within a couple of hundred years and cause the extinction of many species, perhaps even our own.