small logo Publications Department

Book Review:
Lonely Planets
by David Grinspoon
Reviewed by Athena Andreadis
email: Athena.Andreadis @

Its detractors have called astrobiology “the science without a subject”. Astrophysicists, astrochemists and astrogeologists are drowning in data from the planetary missions and the Hubble. At this point, they can all reasonably state that processes which occur in our X (for X substitute galaxy, solar system, planet, depending on your field) also occur elsewhere and therefore can be used to deduce general principles. Paradigm-shifting surprises come often enough but the mode is highly successful until we hit the cement wall of biology. No Martians, Jovians, Titanese or Europans have yet waved appendages at our crafts, and the SETI search has so far collected only the hiss of inanimate events (the Wow! signal notwithstanding).

So astrobiologists, unlike their luckier equivalents, can only philosophize – or extrapolate from extreme terrestrial environments which harbor very exotic organisms, indeed, but share one common denominator: life in such niches is often remarkably complex but it does not qualify as intelligent by our definition. And let’s face it; bacteria and fungi do not fire the imagination. It is really companions and playmates that we are seeking when we extend the SETI antennae. After all, we sent a recording of Chuck Berry into space in hopes of locating creatures that would share our enthusiasm for this heroic, now intergalactic, guitar slinger.

Since astrobiologists lack a truly independent second life sample, they still cannot determine what is universal and what is parochial. Is carbon the universal scaffolding? Is water the universal solvent? Is DNA (or a nucleic acid double helix) the universal genetic transmitter? Is manual dexterity or language the universal prerequisite for intelligence? Can a civilization live forever? You can see at a glance that such questions do not position a scientist favorably for getting either grants or tenure, which is why they have been a domain traditionally reserved as a playground for famous (that is, tenured, fully salaried and grant-flush) scientists.

So what is a young and eager astrobiologist to do? If she is of the applied persuasion, she explores sulfur-based ecosystems in caves or tries to join NASA planetary mission groups. If, on the other hand, he is of the theoretical persuasion, he writes a book. Books about astrobiology have been appearing at a brisk clip the last few years, though only one was brave enough to openly flaunt the word itself in its title (David Darling’s Life Everywhere: The Maverick Science of Astrobiology). All others hedge their bets by purporting to deal with something else (Fermi’s paradox, the uniqueness of earth, the big picture) and attempt to bolster sales by using “Alien/s” in their titles. To this category belongs David Grinspoon’s Lonely Planets: The Natural Philosophy of Alien Life.

David Grinspoon is officially a planetary scientist and has written a book on Venus to prove his legitimacy to the academic guild, which tends to be as punitive as Yahweh about rompings of its members outside the fold. With the more mainstream book under his belt, he can afford to show that he is clearly excited and well informed about his true subject – namely, what we know and can deduce about the requirements for extraterrestrial life. His interest in the field is not surprising: he mentions repeatedly that his parents and grandparents were friends with Asimov and Sagan, who served as his intellectual mentors. In fact, the tone of his book owes much to Sagan’s writing style: it is folksy and accessible, both a meditation and a commentary. It is also occasionally clunky and grating, especially the wan jokey footnotes and the studied humility.

Lonely Planets has three sections. “History” deals with the ebb and flow of opinions about life beyond earth since science became more (or less) than natural philosophy, from the Epicureans to the Sojourner rover, with the usual honorable mentions of such pioneers as Galileo, Immanuel Kant and Percival Lowell. “Science” broadly sums up our current stage of knowledge about the universe, the solar system, earth, the other solar planets and the rapidly expanding roster of exoplanets. “Belief” goes into the question of alien visitations, with the obligatory stops at the Drake Equation and the Fermi paradox, as well as detours which include Orson Welles’ War of the Worlds broadcast and John Mack’s alien abduction theories. So this book combines several aspects that usually appear on separate (and very different) books. Interwoven throughout the narrative are the author’s personal experiences and opinions. The breeziness and anecdotal style recall Joel Achenbach’s Captured by Aliens whereas the biocentric emphasis recalls Jack Cohen’s and Ian Stewart’s What Does a Martian Look Like?

The science in the book is excellent and up to date, though there are very few completely new items in it for those who have been following the field. The novel and refreshing aspects of Grinspoon’s book are some of his less orthodox suggestions and opinions: he shows why astrobiology is in fact a very old discipline, which needs interaction between scientific fields that once were philosophically considered a unit, but are now kept in airtight compartments; he gives persuasive reasons why we should consider Venus (or at least its atmosphere) as a possible harbor for life despite its seemingly very hostile conditions; and he describes life as instrumental in shaping planets, thereby elevating it from a passive outcome to an active partner.

Grinspoon presents all the exciting knowledge gleaned from the robotic missions and powerful telescopes -- the tantalizing results of the Viking experiments, the possible microfossils in Mars meteorites, the ocean which almost certainly lurks beneath Europa’s ice and may harbor life fuelled by geothermal energy, the hot Jupiters and the new insights they gave to models of planetary system formation. Some of his anecdotes shed illumination on thinking outside the box, and how thin the line is between brilliant and kooky– for example, the paper he reviewed and Sagan (as editor) published in the ICARUS journal, which suggested that viral genomes might harbor a extraterrestrial message organized on a grid of two primes. In fact, viral genomes are tightly organized and have overlapping genes because they literally must squeeze their DNA into a confined space; our chances of finding such a message would be higher if we looked into higher organisms, with their profligate expanses of redundant DNA.

There are some omissions and minor errors. Most glaring to a biologist is the lack of explanation of what RNA is and does, given that it is currently our leading candidate for the first protobiotic molecule. There is also the usual sidestepping of the definition of both life and intelligence, with the routine excuse that “We’ll know it when we see it” – when all we know is our present single sample. Grinspoon also performs the Procrustean fits that physicists often resort to when they try to reduce biology to first principles, including the unquestioning presentation of such untested and unproved offshoots as Stuart Kaufmann’s “complexity theory”.

The book also suffers, in my eyes at least, from too much political correctness, and some of its views may inadvertently hurt the scientific mindset that Grinspoon represents. For example, we have come to realize that earth is an integrated system (the “weak” version of the Gaia hypothesis); however, positing humanity as the entity’s brain is bad metaphor and worse science, unless you think Gaia is a very disturbed personality, indeed. Taking science to task for being hostile to bold ideas and for avoiding responsibility for the consequences of their actions plays right into the hands of Proxmire clones. True, science has its vicious politics and rigid hierarchies, but peer review works well for quality control – and death of old fogies clears the way for new concepts. Also, scientists have always wielded negligible political and cultural influence, especially so in today’s USA (quick, name one active scientist outside your field; now name one whom you last saw on prime time TV).

Grinspoon argues for sensitive, socially conscious application of technology, which puts him squarely on the side of the angels. Yet he bypasses the inconvenient fact that such sensitivity can only come into play when technology and its underlying knowledge advance past the point of raw survival. At the same time, he unquestioningly accepts – indeed, hopes – that advanced alien civilizations will possess and wield world-altering technology, the way humans in the past assigned such powers to god(s). Finally, his discussions about science versus religion are oddly conventional and unenlightening (there are shades of Gould’s Nonoverlapping Magisteria in his arguments, a fence-sitting position par excellence). Particularly distressing is his lumping of both SETI and UFOlogy under the category of strictly-on-faith items.

Grinspoon has done a very good overall job, which is why I am complaining about the imperfections of the book. Lonely Planets is an informative, enjoyable book – but with a bit more care and discernment, it could have been an outstanding one.

Editor's Note: Athena Andreadis, PhD is Associate Professor in Cell Biology at the University of Massachusetts Medical School. Her first book, To Seek Out New Life: The Biology of Star Trek, appeared in the spring of '98 and she is now at work on her second, Distant Campfires.

Click to email the Webmaster
| Home | General | Memb Svcs | Publications | Press | Technical | Internet | Index |
entire website copyright © The SETI League, Inc.
this page last updated 31 January 2004
Click for top of page
Top of Page