Researchers at the Lawrence Livermore National Laboratory (LLNL) in California have moved further in their efforts to simulate how they might deflect celestial bodies potentially heading to and potentially hitting the Earth (although the latter is highly improbable), with the findings of their study published in the new issue of the American Geophysical Union journal Earth and Space Science.
The scientists conducted their tests by exploiting a smoothed-particle hydrodynamics code named Spheral to carry out an array of simulations that in turn helped the researchers identify which models and material parameters are the most important to accurately simulate impact scenarios involving a potentially hazardous asteroid.
In addition to the strength model, the team came to the conclusion that simulation results also are very much dependent on strain models and material parameters.
The study separately pinpointed vulnerabilities in the code that could help researchers currently designing a modelling plan for the Double Asteroid Redirection Test (DART) mission slated for 2021, the first-ever kinetic impact deflection demonstration on a near-Earth asteroid.
The accuracy of the codes was looked into by comparing simulation results to the data from a 1991 laboratory experiment conducted at Kyoto University, where a hyper-velocity projectile was targeted at a basalt sphere.
“This study suggests that the DART mission will impart a smaller momentum transfer than previously calculated", said Mike Owen, LLNL physicist, co-author of the paper and developer of the Spheral code.
The team expects the results of the study to come in handy, with the authors stressing the importance of coming up with a solution to possible dilemmas:
“If there were an Earth-bound asteroid, underestimating momentum transfer could mean the difference between a successful deflection mission and an impact. It’s critical we get the right answer. Having real world data to compare to is like having the answer in the back of the book", Owen summed up.
The study's lead author, LNL physicist Tané Remington thinks likewise, implying that it’s better to be safe than sorry:
“We’re preparing for something that has a very low probability of happening in our lifetimes, but a very high consequence if it were to occur", said Tané Remington, going on to assume that time “will be the enemy if we see something headed our way one day".
“We may have a limited window to deflect it, and we will want to be certain that we know how to avert disaster. That’s what this work is all about", Remington explained.