LLNL physicist Mary Burkey developed a novel approach to simulating the energy deposition from a nuclear device on an asteroid’s surface. (Photo: LLNL)
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.
In this illustration of the effects of two neutron yields (50 kt and 1 Mt) and two neutron energies (14.1 MeV and 1 MeV), the black dots represent the location of a nuclear device. Dark blue indicates where the asteroid remains solid, while all other colors show where material has been melted or vaporized. The illustration depicts asteroids with 0.8-m and 5-m diameters—much smaller than the 300-m asteroid simulated in the study—to enhance the visibility of the area of the energy deposition. Image: LLNL
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.
