Chinese scientists propose buried nuclear asteroid defense

Chinese researchers have proposed a new planetary defense strategy that involves burying and detonating a nuclear warhead deep inside an Earth-threatening asteroid, a method they claim is significantly more effective than surface explosions or kinetic impactors for dealing with large objects on short notice.

Scientists from the China Academy of Launch Vehicle Technology (CALT) outlined a two-stage, automated operation. First, an unmanned spacecraft would deploy a heavy metal penetrator to slam into an incoming asteroid, carving a crater up to 30 meters deep. A second spacecraft would then lower a nuclear device into that cavity and detonate it. The researchers argue that this subterranean explosion dramatically increases energy transfer to the asteroid, either vaporizing it or altering its trajectory far more efficiently than a surface blast.

The proposed system is designed for scenarios with limited warning time of just months or years, where gradual methods like gravitational tractors would be ineffective. According to their study, published in the journal Space Science Technology, a 3-megaton warhead-equivalent to roughly 200 Hiroshima bombs-buried 30 meters deep could...