Scientists simulate nuclear explosion of asteroid

In a step that may help protect the Earth from potentially dangerous celestial bodies, scientists have simulated the nuclear explosion of an asteroid in such a way that its irradiated fragments do not fall on our planet.
With the help of supercomputer SKIF Cyberia, the nuclear explosion of an asteroid 200 metres in diameter was simulated.
"The way we propose to eliminate the threat from space is reasonable to use in case of the impossibility of the soft disposal of an object from a collision in orbit and for the elimination of an object that is constantly returning to Earth," said Tatiana Galushina, from Tomsk State University (TSU) in Russia.

"Previously, as a preventive measure, it was proposed to abolish the asteroid on its approach to our planet, but this could lead to catastrophic consequences - a fall to Earth of the majority of the highly radioactive fragments," said Galushina.
TSU scientists with colleagues from other research centres have offered another solution to the problem. It is known that the majority of dangerous objects pass close to Earth several times before the collision.
Therefore, there is a possibility to blow up the asteroid at the time when it is farther from the planet. This measure will be much more effective and safer.

For computer modelling as a potential target was taken a celestial body with a diameter of 200 metres, similar to the asteroid Apophis, which in 2029 will approach Earth at a distance of 38,000 kilometres.

Calculations have shown that for the destruction of the object there must be the impact of a nuclear device with energy of one megaton of TNT equivalent.
In this case, part of the asteroid turns into gas and liquid droplets, and some will break into pieces no larger than 10 metres. This is the maximum in terms of safety for the Earth.
"Because the rocket catches behind the asteroid, almost all the pieces after the destruction will fly forward," said Galushina.

"In this case the orbit of the fragments will be significantly different from the asteroid's orbit. For 10 years after the explosion an insignificant number of fragments will fall to Earth," Galushina said.
"Their radioactivity during this time will be reduced considerably, and after a few years they will not pose a danger.
"It is worth adding that nuclear explosions in space are prohibited by international treaty, but in the case of a real threat to humanity maybe there will be an exception to this rule," Galushina added.