Life as We Do Not Know It: The NASA Search for (and Synthesis of) Alien Life
I just found Peter Ward’s second book Life As We Do Not Know It: The NASA Search for (and Synthesis of) Alien Life, New York, Penguin Group, 2005. Here he considers life itself—what it is, where in the universe it
might be, and however it might be re-invented here soon.
After I finish reading it, I might review Life… in more depth, but for now I like it enough to recommend it and its prequel Rare Earth: Why Complex Life Is Uncommon in the Universe, Peter D. Ward and Donald Brownlee, New York, Springer-Verlag, 2000 for an in-depth, open argument that makes a lot of sense to me.
The authors’ Rare Earth Hypothesis is based on credible astronomical and biochemical possibilities, suggesting that microbial life is much easier “…to evolve from non life…and…should be found widely throughout habitable planets and moons in the cosmos…” while complex animals and plants are very rare. Complex life is relatively fragile and requires “narrow environmental conditions to survive,” as well as long-term
stability in habitable conditions in order to evolve.
For that reasoning, Rare Earth was disliked by SETI and science fiction fans, who ignored the book’s emphasis on the observation that “…simple life should be common.” Ward and Brownlee argued that a long period of habitability required for the evolution of complex, large, oxygen-powered animals was made difficult by the requirement for a long list of astronomical accidents and for “…new information from oceanography, geology and paleontology” that has created the new science called astrobiology.
Peter Ward is a realist. He readily explores all the options he can muster. In Rare Earth he and Brownlee note that the huge numbers of stars and “their inevitable planets” make the existence of “intelligent
civilizations [in the universe] a near inevitability.” I guess that’s good enough for me.
However, the huge distances and time considerations make any contact, even detection, between such civilizations highly unlikely. Perhaps Carl Sagan did us no favors with his optimism. The continuing SETI search is
certainly worth doing, IF we can afford the resources it requires. A big IF as we consider our limits.
As a realist, Ward begins Life… by observing that the universe is so large and diverse, it is “…reasonable to suppose that all manners of life are possible.” On the other hand, it is also possible that there “…might not be anything except carbon based life-forms, [and] DNA might not be …just one way but the only way.”
We are a sample of one, but we’ve learned enough about physics, astronomy and biochemistry in the last few decades to be realistic about both diverse universality and down-to-Earth chemical probabilities. In
any case, ‘tis the season to be jolly that life found a way to start up on Earth and keep going until it developed the means to understand the stars and be thankful for brains that can argue about who else is out