Carl Sagan
2026
Astrophysicist · Astrobiologist · Science Communicator
Carl Sagan was one of the most influential scientists and science communicators in the twentieth century. He held a doctorate in astrophysics and astronomy and contributed important research on Venus’ greenhouse effect and the seasons on Mars. Sagan also helped lay the groundwork for two new scientific disciplines: planetary science and exobiology, or the study of potential life on other planets. He co-founded The Planetary Society and served as a trustee for the Search for Extraterrestrial Intelligence (SETI) Institute. While working as an advisor to NASA, he helped design and implement several missions to Venus, Mars, Jupiter, and the outer solar system.
While his academic and professional achievements were undeniably stellar, it was his skills as a science educator that have cemented him as a beloved figure in popular culture. He was gifted at breaking down scientific concepts into poetic explanations that the public could readily take inspiration from, while avoiding talking down to them. Through numerous books, essays, public lectures, and dozens of appearances on The Tonight Show Starring Johnny Carson, he encouraged people to embrace curiosity, critical thinking, and evidence-based reasoning. These efforts reached a global audience with the 1980 television series Cosmos: A Personal Voyage which combined stories about cosmology, history, and philosophy and related them all back to the everyday experience of living as a human on planet Earth. Its influence extended across generations, inspiring many future scientists, educators, and explorers.
“It is the responsibility of scientists never to suppress knowledge, no matter how awkward that knowledge is, no matter how it may bother those in power; we are not smart enough to decide which pieces of knowledge are permissible and which are not.”
At Sagan’s request, NASA commanded its Voyager 1 spacecraft to turn its camera on Earth, creating an image that came to be known as the Pale Blue Dot, one of the most famous pictures of Earth from space ever taken. Sagan emphasized that recognizing our planet’s diminutive status in the universe should inspire humility, compassion, and responsibility toward one another and the environment.
“There is perhaps no better demonstration of the folly of human conceits than this distant image of our tiny world. To me, it underscores our responsibility to deal more kindly with one another, and to preserve and cherish the pale blue dot, the only home we've ever known.”
Throughout his career, Sagan advocated for scientific inquiry while warning against pseudoscience, superstition, and misinformation. While he championed openness to new ideas, even ones that appear bizarre on their face, he knew that this openness must be tempered by ruthless skepticism wielded as a tool for separating truth from falsehood.
“If we are not able to ask skeptical questions to interrogate those who tell us something is true, to be skeptical of those in authority, then we’re up for grabs for the next charlatan — political or religious — who comes ambling along.”
Amidst a life dedicated to scientific rigor, Sagan managed to find within himself the compassion to show the everyday public that the clinical pursuit of science could be filled with awe, beauty, and joy. In doing so, he courageously shared his personal adoration and passion for the subject with the world. And we saw that he was made of the most dazzling star-stuff the cosmos has to offer.