Five Billion Years of Solitude
Lee Billings
New York: Current (Penguin), 2013
Lee Billlings’ 2013 book concerns the search for habitable exoplanets and the people who have been at the center of the relevant science for the last fifty or more years. Starting with Frank Drake the originator and mind behind the SETI project, the story takes us across the US and sometimes to Europe as the focus shifts from scanning the skies for signals from space to putting ever more complex and delicate telescopes into either earth orbit or even further out near the edges of our solar system. It is a story of vision, hope, and heartbreak, as the most ambitious plans routinely become too expensive for a world that has fought numerous wars, gone through major recessions, and been sidetracked by other space ventures. Billings tells the story with vivid language, capturing the soaring heights of the possibilities imagined by the researchers, almost all of whom are living out a childhood fantasy of finding aliens in the vast dark void that surrounds us, and to the depths of their despair when plans they are convinced will make their dreams true, are abandoned. We get to know each scientist personally, their stories inspiring and sometimes heart wrenching. The author’s own competent mastery of the scientific concepts involved in the approaches used by many different disciplines, from astronomy to geology, makes esoteric scientific ideas understandable to the non-expert reader.
A large part of the impact of Five Billion Years of Solitude is the way Billings places the search for habitable planets outside our solar system within the context of the history of our planet—the nearly five billion years earth has been around. This is important for practical reasons, most importantly, perhaps, being the fact that human life on our planet has existed for only .005% of our world’s lifespan. Not only were there no humans during most of earth’s history, but the planet was also barely recognizable as what we see today for much of the time. Oceans have been here from almost the beginning, fed by water brought to earth by asteroids and comets. But green, leafy vegetation is a fairly recent phenomenon, less than half a billion years old. The location of oceans, seas, mountain ranges, and whole continents, has been changing constantly for much of our lifespan. Volcanic activity, once commonplace, has been rare and sporadic during recorded human civilization. The importance of this is that, if another species from another planet were looking at earth, they would see it inhabited for only a brief moment of its history. Even being habitable, in the sense of being able to support life, has been true for only a portion of earth’s duration. This means that, similarly, we are more likely to discover habitable planets during a period of their history when life, and particularly intelligent life, does not exist on them, even if they have intelligent life at some point in their history.
There are also limits on how long intelligent life will continue to exist as a planet such as earth ages past its maximally habitable period.
For reasons related to increasing temperatures from an expanding sun, causing changes in the composition of our atmosphere—mostly a decrease in the amount of CO2 available for plant respiration involving photosynthesis, the oxygen-producing plants will die off and, for aerobic creatures like us, life will be impossible, an outcome proposed by James Lovelock, famous for his Gaia hypothesis. Depending on whether he is correct or, instead, a process based on rocks releasing oxygen into the atmosphere, is sufficient to sustain life, as described by James Kasting, humans have between 100 million and 500 million years of life left on our planet. That may seem like a lot, and it is, but either estimate is much sooner than the time when increasing temperatures from the expanding sun will extinguish all life on the planet. As Billings points out, such a forecast, when it was made, back in the early 1990s, largely “fell on deaf ears” among the wider public, but the scientific community was alarmed. Either there had to be a way, through advanced technology, such as erecting a solar shield, to keep the earth cool and extend the span of life, or humans could leave earth and move to another planet. Moving outward toward Mars or a moon of Jupiter would extend life considerably but becoming nimble enough to leave our solar system and find younger, life-sustaining planets orbiting other stars, could extend our species’ lifespan indefinitely. With that in mind, some within the scientific community, saw the discovery of habitable exoplanets around other stars as our major hope. For many of those involved in the search for habitable exoplanets, Such as famed MIT astronomer, Sara Seager, the certainty of the end of life on earth is a major motivator.
With the revolutionary pictures coming back from the earth-orbiting Hubble telescope in the 1990s, the astronomical means for detecting habitable planets shifted from earth to space. Larger and larger telescopes at greater distances from earth were seen as the solution, but the issue of how to mask out the light of stars to pick up the dim glow of small, earth-size planets orbiting near enough to their stars to support water and an atmosphere, presented a major problem. That question was inexorably tied to the limits of the size and weight a rocket could carry into space and ultimately to the cost of doing so. Much of the last third of Billings’ book is devoted to the rollercoaster ups and downs of federal funding and NASA priorities over the last 30 years, described poignantly by NASA/JPL chief scientist overseeing exoplanet programs, Wesley Traub, that have led to large dreams and hollow rewards, as promised funding invariably dried up.
Billings tells a stirring story. He able to capture the scientific sprit enough to make a reader such as myself desperate for progress and for our race to dedicate itself to finding other worlds and exploring them for their ability to sustain life. There’s also the mystery, encapsulated most by Frank Drake’s sometime lonely pioneering efforts to keep listening to space for signs that we’re not alone. At least some of the scientists discussed by Billings believe that the limits that permit life, and factors such as convergent evolution, make life with something resembling human type of intelligence highly likely, wherever it is found. The question of what such alien life might be like, is something explored by Jon Willis, in his book, A Pale Blue Data Point, which I’m about to start reading. I’m confident it will keep this story going, and I look forward to telling you about it when I finish reading.
Interested in scif-fi about AIs solving moral dilemmas in a future that has them exploring our galaxy? Read Casey Dorman’s Voyages of the Delphinovels: Ezekiel’s Brain and Prime Directive. Available on Amazon. Click Here!
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