The same high energy density that makes nuclear energy a clean and efficient source of power could make it a good alternative to defend the planet against catastrophic asteroid impacts. NASA demonstrated the world’s first planetary defense technology in September 2022 by deliberately crashing a “kinetic impactor”—a heavy, box-like spacecraft—into an asteroid. Now, researchers at Lawrence Livermore National Laboratory have developed a new tool to model how a nuclear device could deflect—or even destroy—an asteroid threat to Earth in a more efficient and controlled way.

A research collaboration between Lawrence Livermore National Laboratory and the Air Force Institute of Technology (AFIT) has investigated how the neutron energy generated by the detonation of a nuclear device could affect the path and speed of an asteroid on a collision course with Earth by melting and vaporizing a portion of the asteroid. The research, which compared the deflection caused by two different neutron energies—14.1 MeV and 1 MeV, representing fusion and fission neutrons, respectively—is described in an article published by LLNL on April 8.