Planetary Defense Mission Using Guided Collision of Near-Earth Objects

The Baseline Instrumented Lithology Lander, Inspector, and Asteroid Redirection Demonstration System is a proposed demonstration mission to characterize a small asteroid less than 10 m in diameter and redirect it to collide with a larger asteroid hundreds of meters in diameter. This collision will disrupt the larger asteroid or alter its trajectory, thereby demonstrating a capability to prevent such an asteroid from colliding with Earth. The concept of redirecting a smaller asteroid into a larger asteroid is attractive for this type of mission because it uses natural kinetic energy available beyond Earth’s gravity well for the majority of the energy delivered to the larger asteroid. By contrast, a kinetic impactor launched directly from Earth to its target must have all of its mass lifted out of Earth’s gravity well. The proposed architecture allows for an impact energy of several terajoules without the use of nuclear devices. This work presents a novel approach to this type of kinetic impactor mission. In the proposed concept of operations, a spacecraft performs a controlled rendezvous and capture of the smaller asteroid. It then uses solar electric propulsion to redirect the asteroid over time onto a collision course. A high-thrust terminal guidance system is used to perform final trajectory adjustments in the hours leading to collision with the larger asteroid, ensuring a successful interception.