Nuking Asteroids – Is it our Best Move?

In a world where the possibility of an asteroid threatening Earth’s existence is no longer a far-fetched concept, scientists and researchers are constantly exploring different methods to prevent such a catastrophe. And just when we thought last year’s Dual Asteroid Redirection Test, where a satellite was fired into an asteroid, was impressive enough, a team at Lawrence Livermore National Lab led by Mary Burkey is now simulating a scenario that was depicted in the 1998 space disaster film Armageddon.

As Burkey and her team delved deeper into the possibility of using a nuclear explosive device to deflect an incoming asteroid, they presented a paper at the Planetary Science Journal that took the research to a new level. In their paper, they explain that using a satellite as a missile is not always practical and detonating the nuclear device as close to the asteroid as possible might be a more effective approach.

The only problem is that this method requires precision, as a minor miscalculation could result in the same outcome as depicted in the 1998 film Armageddon – chunks of the asteroid still hitting Earth. This could lead to a widespread devastation scenario, much like the one portrayed in the film Deep Impact.

“Fully simulating the energy deposition requires particle transport within a full radiation-hydrodynamics code equipped with detailed material models and is very computationally expensive, since the time steps must be small to model the interaction of the radiation with the asteroid.”

In simpler terms, the complexity of this simulation is immense. It involves multiple stages and requires various physics packages, which makes it challenging to find a single code that can accurately represent the entire process. Burkey and her team have split the simulation into stages and are using different codes to tackle the various aspects, making it a more feasible approach.

The team also discovered that the majority of the energy produced by a nuclear explosion is in the form of X-rays, which led them to incorporate this crucial aspect into their simulation. By utilizing a full rad-hydro simulation equipped with evolving opacities, they were able to achieve a more comprehensive and accurate simulation.

In essence, this is one of the first simulations to provide a detailed and accurate timeline of what would happen if an asteroid was nuked, down to the microsecond. The simulation, shown below, covers a span of one second:

      Time: 1e+06 microseconds (a million microseconds in one second)
    

The simulation ends with tentative findings, which indicate that this method is accurate enough to be used for larger-scale studies. Now, this has opened doors for numerous potential studies that can be completed using large-scale hydrodynamic codes to gain a better understanding of asteroid-nuking.

“Properties such as the distribution of material/density, rotation, irregular shapes, shadows cast by boulders, the marginal pull of gravity, and even the composition on a larger scale all require more detailed studies of their effect on a mission’s outcome.”

One of the most significant questions in the planetary defense community is whether an attempted deflection mission would break apart the asteroid. With every simulation, the field gets closer to understanding just how effective nuking an asteroid would be.

The team also proposes the need for faster-running simulations to minimize response time in case of a potential threat. With the advancements in technology and the increasing use of machine learning, there is hope that AI can be used to save humanity rather than destroy it – for once.