In this luminous memoir, an MIT astrophysicist must reinvent herself in the wake of tragedy and discovers the power of connection on this planet, even as she searches our galaxy for another Earth. Sara Seager has always been in love with the stars: so many lights in the sky, so much possibility. Now a pioneering planetary scientist, she searches for exoplanets--especially that distant, elusive world that sustains life. But with the unexpected death of Seager's husband, the purpose of her own life becomes hard for her to see. Suddenly, at forty, she is a widow and the single mother of two young boys. For the first time, she feels alone in the universe. As she struggles to navigate her life after loss, Seager takes solace in the alien beauty of exoplanets and the technical challenges of exploration. At the same time, she discovers earthbound connections that feel every bit as wondrous, when strangers and loved ones alike reach out to her across the space of her grief. Among them are the Widows of Concord, a group of women offering advice on everything from home maintenance to dating, and her beloved sons, Max and Alex. Most unexpected of all, there is another kind of one-in-a-billion match, not in the stars but here at home. Probing and invigoratingly honest, The Smallest Lights in the Universe is its own kind of light in the dark.