Astrophysicist Sara Seager’s Memoir Uses the Dark to Find the Light

Metaphorical reasoning has an honorable role in the history and tradition of popular science writing and education. It appears self-consciously but artfully in the work of Alexander von Humboldt, Europe’s first popular science writer, in the first volume of his Cosmos (1845). Mindful that he was writing for a general audience, Humboldt developed an elaborate but intuitive connection between the universe and human consciousness, inviting his readers to imagine how our “portrait” of nature is gradually revealed and experienced as we discover, paint, and admire it.

A century and a half later, Carl Sagan earned his place as arguably the greatest science communicator of the era partly through an adeptness for deploying metaphors and analogies carefully designed to help his audience negotiate the conceptual challenges associated with understanding quantum or cosmic size, scales, and timeframes – phenomena that are otherwise not available for us to “see”. Consider the Pale Blue Dot, for example, identified and named by Sagan to symbolize our aloneness in the cosmos and presented as an occasion to consider our unique good fortune to inhabit such a small, beautiful space.

In The Smallest Lights In the Universe, astrophysicist Sara Seager is revealed to be an astute practitioner of metaphor as both a form of reasoning and illustration as well as a source of artful emotional resonance. So thoroughly, in fact, is this memoir steeped in metaphor and analogy, a proper reference point for Seager’s style not that of Humboldt or Sagan, for whom an analogy is drawn up periodically to establish a particular point, but rather that of Charles Darwin, for whom analogy is found to be at the root of his entire system of thought.

Darwin’s prose teems with analogical reasoning, overtly in his nomenclature–”natural selection” and “struggle for experience” are themselves metaphors–as well as hidden carefully in the folds of virtually every paragraph of On the Origin of Species (1859). His metaphors and analogies are pulled from disciplines and areas of life with which he was sure his readers were familiar, even popular religious sources, as in his discussion of a primordial form “into which life was first breathed.”   

The Smallest Lights In the Universe is reminiscent of this literary and immersively metaphorical style. Because it is a memoir that chronicles her career as well as the challenges and traumas of her personal life, she is handling two distinct areas of engagement: the science part, and the emotions part. Both are revealed throughout in beautiful passages and images. As if by habit, again rather like Darwin, she repeatedly ensures that the points at which they intertwine for her–and by extension, for us, as readers–are moments for wonder and for contemplation of simple emotional truths.

She does this through analogy, and the book’s title is the master key for following her. “Light doesn’t just illuminate,” she writes. “Light pollutes. Light blinds. Little lights–exoplanets–have forever been washed out by the bigger lights of their stars, the way those stars are washed out by our sun. To find another Earth, we’d have to find the smallest lights in the universe.”

Seager draws a parallel between the challenges she has faced in her scientific work in astrophysics–which is, she notes, essentially the study of light–and the challenges she has faced in her personal life as neurodivergent, as a woman in a male-dominated field, as a mother, and a wife, and a widow.

The Starshade project, a key feature of Seager’s work in hunting exoplanets, neatly illustrates how deeply woven together are the light and dark and how multiple their meanings are for her. The Starshade is a spacecraft in its own right that, when flown in formation with a telescope, would block out enough light from nearby stars to reveal to us any orbiting planets.

“I tried to imagine the sort of person who would be useful on such a committee. It was me. What sort of brain? It was mine. I knew darkness, and sometimes you need darkness to see.” One needs darkness to appreciate the light–now, for Seager, the metaphorical and literal even come together, because the Starshade is literally an instrumental for using darkness to appreciate the light.  

It is about finding small light in the darkness, about movement, about getting to know the dark, and also about getting out of it. It is about enlarging the picture to light upon the truth. “My life became a study in contrast, the light and the dark, the hopeful and the hopeless,” she writes, as her husband’s health continued to deteriorate.

At one point of despair, she describes a “black spot” inside her, for which “the slightest knock or careless moment” caused it to “become an awful, spreading stain.” She describes travelling through the American southwest “as though we had gone to sleep in one universe and woken up in another.” And she describes an experience at a mountain summit in Hawaii at sunrise “as though in a moment” she had “been given a new horizon.”

Such moments arose from life-altering traumas–such as widowhood and suddenly needing to care for two young sons without having, as she puts it, a Guide to Life on Earth, as well as relatively few opportunities to re-acquaint, to appreciate anew, or to experience for the first time simple truths about beautiful moments. Seager endows these experiences with emotion and poignancy using an idiosyncratic but accessible and resonant metaphorical language.