I also enjoy the 2012 movie Seeking a Friend for the End of the World, which had a somewhat more depressing but, in my opinion, maybe more realistic view of an asteroid threatening Earth (spoiler alert – the last ditch efforts of a crew of astronauts do not work).
The year after this movie was released, a 20-meter asteroid struck the Russian city of Chelyabinsk, and the resulting pressure and winds from the shock wave wreaked all kinds of havoc – breaking windows, damaging buildings up to 58 miles away, sending debris flying, and injuring over 1,200 people. According to the Advanced Supercomputing Division (NAS) at NASA, most windows break under 2 pounds per square inch (psi) of pressure, while it takes 10 psi for larger buildings to collapse, and fires can ignite from the explosion’s resulting thermal radiation. So we know the movies got at least one thing right – asteroid strikes can cause all sorts of damage.If you’re wondering what any of this has to do with 3D printing, we’re not talking about using asteroid material to 3D print autonomous ships, or even using 3D technology to explore the second largest object in the asteroid belt. Rather, researchers are creating 3D asteroid models, which has been done before, and using a powerful NASA supercomputer to produce simulations of hypothetical asteroid impact scenarios.
Aerospace engineer Michael Aftosmis, who runs the Asteroid Threat Assessment Project (ATAP) blast wave and ground damage modeling work at NAS, said, “Asteroid impacts are one of the only natural disasters we can actually predict and then take action to protect people.”
ATAP experts at the NAS facility at NASA’s Ames Research Center in Silicon Valley ran large-scale simulations of the Chelyabinsk event on the Pleiades supercomputer using NASA’s Cart3D modeling software. The software, which is dozens of times faster than the 3D numerical modeling normally used for aerodynamic analysis, ran high-fidelity simulations of the blast from the asteroid’s entry corridor all the way to the surrounding countryside. The team was able to compare their predictions of the blast shock arrival time and overpressures at specific locations, covering over 40,000 square km, with data from the actual event, which was recorded on building and dashboard cameras in the area.
“These are some of the world’s most detailed simulations of this event. We were able to produce many scenarios quickly because Cart3D, normally used for aerodynamics analysis, is dozens of times faster than most hydrocodes used for 3D numerical modeling of the fluid flow that occurs when asteroids melt and vaporize as they break up in the atmosphere,” explained Aftosmis.
“What’s unique about our analysis is that we can rapidly assess so many scenarios while faithfully representing the key physics. This is done by leveraging the airblast, ground, and water impact simulations created by the team, as well as by taking advantage of the NAS compute resources,” said Donovan Mathias, an aerospace engineer who runs the NAS Division’s Engineering Risk Assessment team and ATAP risk modeling work.
All of NASA’s important asteroid research is being shared with scientists at other government agencies, national labs, and universities, who will use the information to work up assessment and response plans, and to inspect warning times, evacuations, infrastructure damage, and options for protecting property and human life. This will increase the chance of humanity’s survival in the case of an E.L.E. or any other kind of damaging asteroid strike. Discuss in the 3D Asteroid Models forum at 3DPB.com.
[Sources: PhysOrg, NASA]