Here is a sentence that could only make sense in 2018: Scientists working with the National Nuclear Security Administration, NASA, and the Energy Department have designed a spacecraft capable of blowing up an asteroid with nukes.

BuzzFeed News reports their vehicle, called Hypervelocity Asteroid Mitigation Mission for Emergency Response (HAMMER), could use a number of tactics to defend Earth from asteroids. Small asteroids could be smashed with HAMMER’s 8.8-ton “impactor,” but for the big boys, HAMMER would use a nuke.

According to a new paper published in the journal Acta Astronautica, the idea for HAMMER came from a 2010 report from the National Research Council about defending Earth from Near Earth Objects (NEOs).

“The two realistic responses considered are the use of a spacecraft functioning as either a kinetic impactor or a nuclear explosive carrier to deflect the approaching NEO,” the researchers write.

Physicist David Dearborn of the Lawrence Livermore National Laboratory elaborated on this to BuzzFeed News.

“If the asteroid is small enough, and we detect it early enough, we can do it with the impactor,” Dearborn says. “The impactor is not as flexible as the nuclear option when we really want to change the speed of the body in a hurry.”

Dearborn and his colleagues considered how HAMMER would fare against a distant asteroid called Bennu, which has a 1 in 2,700 chance of striking Earth on September 21, 2135. They propose that several HAMMER spacecraft would throw themselves in front of the asteroid, slowing it down and deflecting its path to Earth.

OSIRIS-REx will collect a sample of the asteroid Bennu using a the TAGSAM.
NASA's OSIRIS-REx spacecraft collecting a sample of Bennu.

While HAMMER might never actually be built due to various constraints, including cost, the scientists on this project say it’s better to be safe than sorry. The team will present their idea this May at the Workshop on Catastrophic Disruption in the Solar System in Japan.

It bears repeating that this is all a plan for the worst-case scenario. Our first line of defense is just hoping that we never need to exoplode an asteroid.