There is something comforting and reassuring about reading science books. One can also add “rewarding” if reading the book means one is in the capable hands of Sarah Stewart Johnson, author of The Sirens of Mars: Searching for Life on Another World. The book is part science history, part contemporary science, and part memoir and personal journey. While readers derive the comfort and reassurance from the inevitable plethora of indisputable facts, the reward comes from Ms. Johnson’s beautiful and fluent writing, which often has the ability to stir the soul with wonderment about Mars and all other planets in our solar system.
Despite the preceding comment about “plethora of indisputable facts,” the word “conjecture” also pops up quite frequently in this absorbing book, for even hard data often cannot tell the full story, and it is left to energetic and imaginative scientists to ask intelligent what-if questions to derive smart hypotheses and set about proving (or refuting) them. Ms. Johnson pays homage to well-known names in space exploration, from Galileo to Carl Sagan, but also gives fair tribute to less familiar movers and shakers, such as Giovanni Schiparelli and Percival Lowell.
Ms. Johnson provides comprehensive and objective coverage of the many attempts to learn more about our planetary neighbor over the last 30-40 years, including both failures and successes. Despite all the past outcomes being known, her clever narrative accomplishes the remarkable literary feat of placing readers right beside early planetary scientists as they teased out their speculations or had their discoveries confirmed. Whether right or wrong, readers enjoy a sense of discovery all their own. The author herself and colleagues come “under the spell” of each new fact about Mars, and wallow in “tantalizing evidence” gleaned from each new path for exploration. One scientist “could almost taste how good the data would be” from photographs taken on the Mars Observer mission.
Exploration of Mars advanced in (relatively) rapid strides. “Orbiters” of the planet were succeeded by “landers,” which actually touched down on the planet but remained rooted to the spot. Ultimately came the “rovers,” which trekked this way and that across the Martian landscape, conducting experiments and collecting samples, and sending related data to insatiable, Earth-bound scientists for analysis. One valuable addition to this otherwise perfect narrative would have been a timeline of Mars missions, and a selection of photographs would have been real icing on the cake.
Exploratory efforts eventually converge towards trying to answer the question: “Was there, is there, could there be life on Mars?” As well as Johnson’s book, a quick visit to a NASA website on the subject will offer a hedging answer: “We don’t know…yet.” However, the Curiosity rover collected and analyzed rock samples, and allowed scientists to declare that “All six of the elements required for life as we know it were present in the sample: carbon, hydrogen, oxygen, nitrogen, phosphorus, and sulfur.” (The italics are mine, for it is worthy of note that scientists are also quite comfortable with being open to the discovery of life as we don’t know it.) Further heat treatment of the samples led to the discovery of “even more complex molecules, bound together by sulfur…The building blocks of life were indeed there.”
Johnson proves to be a multitasker extraordinaire as she pursues graduate and post-graduate education, participates on several Mars missions, marries and becomes a mother. In fact, the author’s story of Mars becomes most personal when the Curiosity rover (aka the Mars Science Laboratory) was speeding towards a landing on the planet. Though not exactly parallel events, Ms. Johnson does a bewitching and poignant job of juxtaposing the birth of her son into the Earth world with the arrival and landing of Curiosity in the Martian world.
By the end of this fabulously accessible and engaging book, readers are bound to be caught up afresh in the possibility of “other life out there.” And rather than a source for mere wonderment about the possibility, it will morph into a deep yearning for extraterrestrial life to just be out there, gosh darn it! Additionally, Ms. Johnson takes readers convincingly to the point that Mars is simply a beginning of planetary exploration—look out Jupiter!