The Man Who Stands Between Earth and Asteroid Armageddon

Lindley Johnson spent 23 years in the U.S. Air Force keeping his eyes above the skies. He helped identify and tackle a growing risk to human space activity—the sheer volume of stuff orbiting the planet—in addition to helping manage and monitor military assets in orbit. In 1982, the Air Force set up a space command to coordinate its activities, not the least of which was making sure the then-new Space Shuttle fleet wouldn’t have a tragic encounter with spacefaring material.

In the early 1990s, Johnson’s focus turned to natural threats to the planet from near-Earth asteroids, now a large and growing class of rocks that scientists track both for their potential impact risk and to study the solar system. About 1,500 new objects are discovered every year. Since retiring as a lieutenant colonel several years ago, he’s become the founding head of NASA’s Planetary Defense Coordination Office, overseeing a network of ground-based telescope surveys for new asteroids and working with other agencies to prepare for the unlikely event of a direct hit. His job title—no pressure—is Planetary Defense Officer.