On March 24, 2015, I photographed Nobel Laureate John Mather at the National Academies, capturing a man whose work has fundamentally shaped our understanding of the cosmos. Mather, an astrophysicist with a quiet but unmistakable intensity, has spent a lifetime unraveling the deepest mysteries of the universe, from the remnants of the Big Bang to the search for habitable worlds beyond our own.

Mather’s Nobel Prize-winning work on the Cosmic Background Explorer (COBE) provided some of the most compelling evidence for the Big Bang theory, measuring the faint afterglow of the universe’s birth with unprecedented precision. His findings helped cement our understanding of how the cosmos evolved, offering a glimpse into the earliest moments of existence.

But Mather’s influence extends far beyond COBE. He played a central role in the development of the James Webb Space Telescope (JWST), a project so ambitious it was often likened to an engineering miracle. For decades, he worked to bring the telescope to life, shepherding its journey from concept to launch, and ensuring that it would push the boundaries of our cosmic vision. Thanks to his leadership, JWST now peers into the depths of space, uncovering the first galaxies, probing the atmospheres of exoplanets, and rewriting our understanding of the universe in real time.

Despite the grand scale of his work, Mather himself is deeply grounded, with a scientist’s precision and a philosopher’s curiosity. When I photographed him, he carried the weight of knowledge lightly, thoughtful, methodical, and generous in his explanations. His work is a reminder that science is, at its core, a form of exploration, an insatiable pursuit of the unknown. And few have charted as many frontiers as John Mather.