She opened Cosmos to the first page and began reading again. This time, not as a granddaughter mourning, but as a student taking a very old, very beautiful exam.

In the dim light of a falling autumn afternoon, a young woman named Ariadne climbed the rickety ladder to her grandfather’s attic. He had died three weeks ago, and the family had finally gathered to sort through what he’d left behind: old tools, yellowed photographs, a clock that no longer ticked.

Somewhere, across the galaxy, photons that had touched her grandfather’s face were still traveling outward at the speed of light. They would never stop. Neither would the carbon from his smile, the calcium from his hands.

She took a deep breath. The air was mostly nitrogen from ancient volcanoes, oxygen from the breath of prehistoric algae, and argon left over from the birth of the Milky Way. She exhaled.

She sat down on a crate and began to read. That night, Ariadne carried the book to the pier where her grandfather had once taught her to tie knots and tell time by the stars. She read aloud to the lapping water: