Using nuclear warheads to destroy or alter the trajectory of an asteroid that is destroying the Earth is a plot line in disaster movies like "Armageddon" and "Deep Impact." Now, scientists have developed a new system that can simulate the use of a nuclear device to do just that.
The Planetary Science Journal published a study titled "X-ray Energy Deposition Model Modeling Asteroid Responses to Planetary Defense Nuclear Mitigation Missions." The study points out that in the event of a potentially catastrophic asteroid impact, if there is sufficient warning time, deploying nuclear devices remains a strong option for planetary defense where other methods prove inadequate.
The study introduces a new method for simulating the propagation of X-ray energy from nuclear devices on asteroid surfaces. These simulations require a variety of complex physics software packages and are computationally expensive.
To explore the mission's sensitivity to the various physical properties of the asteroid, an efficient and accurate way to simulate this system is necessary, the researchers wrote. The system must also operate at high speed to allow sufficient time to prepare countermeasures. The new model developed by LLNL also takes into account many complex factors, such as the penetration of radiation and light into the asteroid material.
"If a true planetary defense emergency arises, decisions around launching reconnaissance and/or mitigation missions will require state-of-the-art modeling and simulation capabilities," the researchers explained.
"If we had enough warning time, we could potentially launch a nuclear device and send it millions of miles to an asteroid heading toward Earth," said LLNL physicist Mary Burkey. "We could then detonate the device or deflect the asteroid, leaving it intact but pushing it away from Earth in a controlled manner, or we could destroy the asteroid and break it into small, fast-moving fragments that would no longer be aimed at Earth."
The study notes that significant progress has been made in developing options to prevent catastrophic impacts to Earth, most notably NASA's Double Asteroid Redirect Test (DART). During the 2022 mission, a 1,260-pound spacecraft deliberately crashed into a 530-foot-wide asteroid called Dimorphos at 14,000 miles per hour. The mission was a huge success, shortening the asteroid's orbit by 33 minutes. As a result of the collision, Dimorphos' orbit around its larger parent asteroid Didymos was shortened from 11 hours and 55 minutes to 11 hours and 23 minutes.
LLNL physicist Megan Bruck-Syal warned: "While the probability of a large asteroid impact in our lifetime is low, the potential consequences could be devastating. With the new model, hopefully humans will have more options when it comes to preventing huge space objects from hitting our planet."