“The cosmos is within us,” Carl Sagan once said. “We are made of star-stuff. We are a way for the universe to know itself.” Nervous System, by Lina Meruane, is a slim elliptical novel which takes this sentiment very much to heart. Ella, the main character, is a student of astronomy and she sees stardust and planets everywhere she looks. The novel abounds with scientific imagery: a mole on a neighbor’s cheek is like a star; Ella and her boyfriend El are an electron and a positron, each the other’s opposite; an MRI machine is a black hole.

Very little action happens in Nervous System. If you sketch out the plot beats they seem barely enough to flesh out a short story. Ella struggles to finish her astronomy dissertation. She wishes she could get sick, so she could be relieved of her teaching duties; then she does become ill, a mysterious lesion appearing on her spine, and she regrets her wish. She allows her father to pay for her studies but worries that she is wasting his money. The major events in her life — her mother’s death, a breakup, a move to another country — are hinted at rather than expanded upon. Nearly everything that might be of ordinary interest happens off-stage.

What Meruane wants to write about instead are illnesses and injuries. Each chapter centers on the maladies and mishaps of a different character, and each chapter has a scientific title and theme, such as “stardust” or “gravity.” Sometimes the theme illuminates the characters beautifully. Associating Ella with black holes and El with explosions gives the reader an interesting window into their relationship. At other times the theme falters — associating the milky way with Ella’s stepmother and her breast cancer struck me as, let’s say, overly literal.

Peppered throughout the book are asides about astronomy, or — as Ella corrects El at one point — “extraterrestrial planetary sciences.” These seem like digressions, but feature some of the most arresting writing in the book. For example, Ella ponders the universe:

An old cosmologist conjectured that after the big bang there must have been other, smaller explosions that produced infinite pocket universes scattered through space. Some empty and others saturated with matter, some eternal, others ephemeral, others that were expanding too quickly and violated the human laws of physics. But why would they be so different? Ella thought. Why was it only humans who were lucky enough to live in a space specially designed for them? A space, a planet, that humans seemed intent on destroying. 

Life on earth was composed of 82 percent plants, 13 percent bacteria, and the remaining 5 percent included everything else. Of that everything else, only 0.01 percent was human. And still, that 0.01 percent was finishing off the other species. It was even finishing off itself.

When I finished Nervous System, what stuck with me were not the moments with doctors in hospitals, not Ella’s flailing love life nor her flailing career, but the side notes about stars and planets. These seeming diversions are as central to Ella’s story as her dissertation or the scans of her spine. The universe is part of her. She is part of it.

“What mistakes could we repair?” Ella’s father asks late in the book. “Which one would you start with?” He’s talking about the damage done to the planet, but he’s also talking about Ella and about his own life. It’s a metaphor, sure. But it’s more than that. It’s also a suggestion that learning what has gone wrong with the planet will illuminate what has gone wrong with Ella. She is a way for the universe to know itself, and for us to know the universe. Can the damage to Ella or to Earth be undone? Who can put them right? “Our planet is a lonely speck in the great enveloping cosmic dark,” wrote Carl Sagan. “In our obscurity, in all this vastness, there is no hint that help will come from elsewhere to save us from ourselves.”