03 October 2022

Scientists from Immanuel Kant Baltic Federal University showed with the help of mathematical calculation that the only way to prevent the falling of the kilometer-long asteroids on the Earth is to trigger a powerful thermonuclear explosion on their surface, that enables to correct their trajectory or to fracture the dangerous object into smaller pieces. Asteroids of such size may collide with the Earth once in a 500 thousand of years and cause the partial destruction of human civilization. This work helps to assess the technical applicability of various methods of struggling with potentially dangerous cosmic bodies. The results of the research are published in the magazine Cosmic Research.

 Asteroids are relatively small cosmic bodies, that travel on the certain orbit around the Sun.  They differ from larger planets and smaller meteorites in size: asteroid’s diameter usually varies from 30 meters to one thousand kilometers. There are two places of mass gathering of asteroids in Solar system – main asteroid belt between Mars and Jupiter’s orbits, and also Kuiper belt in the outer Solar system.

Sometimes asteroids can move closer and collide with planets, including the Earth. The bigger the cosmic body is, the more destroying effects these blows have. Thus, if the asteroid of hundred meters in diameter collides with the Earth, it will cause the explosion, that exceeds the energy of nuclear bombs in Hiroshima and Nagasaki in tens of thousands of times. And this event occurs once in ten thousand years, and the collision of asteroid with diameter about thirty meters – once in 150 years. In this connection we need methods that enable to prevent such collisions in future.

Nowadays there exists two ways of defending from asteroids: to correct its trajectory or to destroy it into smaller pieces that are not dangerous and will completely burn in the atmosphere. In the nearest future NASA will experimentally test the first one by sending space vehicle DART to the asteroid Dimorphos, that is not dangerous for the Earth, in order to correct its trajectory.

Members of scientific group, from right to left: A. Teplyakov, M. Nikitin, A. Baigashov. Source: Michail Nikitin

Members of scientific group, from right to left: A. Teplyakov, M. Nikitin, A. Baigashov. Source: Michail Nikitin

Technically there are several ways of prevention the danger of falling of small asteroids on the Earth: you can send to asteroid a cosmic vehicle that joins it and with the help of exhaust thrust moves the dangerous object aside, or to strike the cosmic body with ram rocket, that will change its flight direction or break into pieces. The last way is more efficient technically, because it requires less heavy vehicles. However, for bigger asteroids the situation becomes more complicated.

Scientists from the Immanuel Kant Baltic Federal University studied the possibility of destroying or correcting trajectory of kilometer-long asteroids with the help of powerful thermonuclear explosions. The model calculations showed that putting such cosmic bodies on a safe trajectory requires superpower nuclear explosions at distances of more than 100 million km from the Earth. It was also clearly shown that by such measures kilometer-long asteroids  most likely be fragmented. 

The latter circumstance makes the task of correcting the trajectories of such asteroids using nuclear explosions difficult to achieve because of the difficulties in predicting the trajectories of motion of the fragments formed.

“Our calculations showed that it’s technically possible to defend from kilometer-long asteroids. However, to make this defense effective, the active influence on asteroids must be conducted at the considerable distance from the Earth. In this connection it’s vital to observe the potentially dangerous asteroids in order to make the nuclear correction of their trajectories in advance. As powerful nuclear explosions will most likely cause the destruction of such cosmic bodies, in future we plan to calculate the trajectories of dispersion of large asteroid’s pieces after their fragmentation”, - shared his plans Mikhail Nikitin, Doctor of Physical and Mathematical Sciences, Professor of the Immanuel Kant Baltic Federal University.