Relying on the scale and composition of the asteroid and the ability of the nuclear gadget, an explosion might probably shatter an asteroid into items. Whether or not the fragments missed the planet altogether or continued on the identical impression trajectory may depend upon the identical elements — measurement, composition, and energy of the explosion. Though some fragments is perhaps sufficiently small to dissipate within the environment, different chunks of asteroid could still pose a serious threat and may rain down over a large space of the planet.
One other strategy to nuking an incoming asteroid can be to detonate the nuclear gadget close to, moderately than on, the floor of the asteroid. This fashion, the explosion might trigger the asteroid’s floor materials to vaporize and ablate, making a thrust that might alter the asteroid’s trajectory with out inflicting vital fragmentation.
Any try to destroy or divert an asteroid utilizing nuclear detonations would probably require a mission to review that asteroid up shut beforehand to search out out what it’s fabricated from, the way it’s structured, and how much pressure can be wanted to successfully deflect or destroy it with out turning one impression menace into many.
Worldwide treaty issues
The usage of nuclear weapons in house is strictly prohibited underneath the worldwide Outer Area Treaty, and for excellent purpose. Throughout the Chilly Conflict, the Soviet Union and the US competed to develop highly effective rockets and nuclear weapons, going as far as to check nuclear weapons in house. In response to this arms race, the United Nations drafted the Outer Area Treaty, to which all main spacefaring nations have agreed.
Whereas sending a nuclear weapon into house for asteroid deflection is clearly not the identical as utilizing a nuclear weapon for struggle, it’s doable that the usage of nuclear arms in house might create geopolitical tensions or set a bad precedent for future army actions in house. That is one purpose why the nuclear possibility is just not essentially essentially the most simple approach of coping with an asteroid menace.
Different choices are on the market
Fortunately, there are different methods of deflecting an asteroid that don’t pose the identical challenges as nuclear detonations.
One approach is the sluggish gravity tractor, the place a large spacecraft is launched from Earth to satisfy the asteroid and comply with subsequent to it, utilizing the spacecraft’s personal gravity to tug the thing’s path away from a future collision. One other approach is laser ablation, the place one or many spacecraft apporach the asteroid and use lasers to vaporize rock to create jets that sluggish or pace the thing’s path across the Solar. The Planetary Society labored with a workforce on the College of Strathclyde in Scotland to develop early lab analysis into this method, by means of their Laser Bees challenge.
There’s additionally the kinetic impactor approach, the place a number of spacecraft slam into the asteroid to impart a bit of pressure to shift its orbit. NASA’s DART (Double Asteroid Redirection Take a look at) mission proved the effectiveness of this method in September 2022 when the spacecraft deliberately crashed into the asteroid Didymos’ small moon, Dimorphos. The crash modified the time it takes Dimorphos to orbit Didymos by 33 minutes, proving the kinetic impactor approach works to alter an asteroid’s trajectory by means of house.