REVIEW: “The New Science of Astrobiology” by Sara Imari Walker

Review of Sara Imari Walker, “The New Science of Astrobiology”, in Visions, Ventures, Escape Velocities: A Collection of Space Futures, edited by Ed Finn and Joey Eschrich, (Center for Science and Imagination, Arizona State University, 2017): 243-250 — Download here. Reviewed by Sara L. Uckelman. (Read the review of the anthology).

I love the title of this piece. “Astrobiology” by itself is a fascinating word full of potential; when you put “science” in front of it, you get something tangible and concrete, not merely imagination. When you add “new” to the front of that, then you’re back in the border between fiction and fact again, forging a way from what we can imagine to what we can actually know.

Astrobiology seeks to address one of the most difficult open questions in
science: Are we alone? (243)

Walker cuts right to the chase: The reason this question is hard to answer is not merely because of the technological complications involved, but because it requires us to first answer another, more fundamental, and much more difficult question:

What is life? (243)

Scientists have no answer to this question; even philosophers stumble when they attempt to; but are we surprised that it is the tellers of stories, the fiction authors amongst us that have the best attempts? Waker analyses how Singh in “Shikasta” (read the review) manages to present a fictional planet which is both exotic i>and realistic, where the concepts of ‘living’ and ‘life’ are realised in ways radically different from how they are realised on earth.

This is the key point that Walker makes in her paper: When astrobiologists team up with space exploration projects to find signs of life in the universe — so-called “biosignatures” — they are looking for biosignatures like ours (Walker goes into a lovely amount of detail in the biochemistry of earht-like biosignatures, for those who are interested). How can we even know what a biosignature not like ours would looke like? This is where the imaginists, the authors, the speculators come in. Stories like Singh’s, Walker argues, provide us a means for conceptualising a different approach to what it means to be alive, and hence different paths to answering the questions “are we alone?”, and, more fundamentally, “who are we?”