NASA scientists have developed a technology called HAMMER to deflect potentially deadly near-Earth objects, or NEO, such as massive asteroids headed toward our planet. Findings of a new study, however, have revealed that it would not be enough to keep Earth safe from dangerous space rocks.
The Bennu asteroid has a slim but significant chance of colliding with Earth by the year 2135 but if there would be an impact, the consequences could be catastrophic. It could generate a force 80,000 times more powerful than the bomb dropped on Hiroshima, Japan. Researchers now reveal that in significant dangers such as the Bennu asteroid, deflecting NEOs would not be enough.
Deflecting Asteroids That Can Potentially Hit Earth
Brent Barbee, from NASA's Goddard Space Flight Center, and colleagues looked at the current plan for preventing asteroids from colliding with planet Earth. The first part is the development of a craft that can be fired at the asteroid to change its trajectory. The idea is to ram the spacecraft into the asteroid using just enough force to shove the space rock and slow it down without causing it to break apart.
The researchers, however, found that it would take as many as 50 different launches to safely deflect the asteroid away. Worse, the success of such effort is not guaranteed.
"When many launches are required for a successful deflection, the mission success becomes more difficult, due to the failure rate associated with each individual launch," said Megan Bruck Syal, from Lawrence Livermore National Laboratory.
"If we only had 10 years from launch, we would need to hit Bennu with hundreds of tons of HAMMER mass just to barely deflect it off of an Earth-impacting path, requiring dozens of successful launches and impact at the asteroid."
Other Options To Protect Earth From Dangerous NEO Collision
Scientists may have to go for the nuclear option, which involves shooting a warhead at the space rock to destroy it. It isn't just Bennu that poses problem. Other dangerous rocks may also be spotted too late before they are about to collide with Earth. This could make deflection difficult and may necessitate blowing up the asteroid instead.
"Whenever practical, the kinetic impactor is the preferred approach, but various factors, such as large uncertainties or short available response time, reduce the kinetic impactor's suitability and, ultimately, eliminate its sufficiency," Barbee and colleagues wrote in their study, which was a published in Acta Astronautica.