Comet Lovejoy, observed from the space station in 2011 (NASA)
If the Earth is threatened by a comet, then we will have too little time to prepare. But a stock of nuclear warheads could hedge against an existential threat.
When comet Siding Spring (C / 2013 A1) was only discovered at the beginning of 2013, initial predictions said that there was a negligible chance that it would crash into Mars. The idea that a comet with a half-mile width would eventually pass very close to the Red Planet disappointed computational geophysicist Kati Plesko.
“I think I was the most excited man on the planet!” She recalled. “If she had crashed into Mars, I would have published a thesis with predictions about how this happened.”
Plesko works at the National Laboratory in Los Alamos (California) with a team of scientists who focus on studying the effects on planetary bodies and modeling their mitigation methods. A blow to Mars would be lucky, as her 2009 doctoral one was based on the impact of comets on Mars. If a disaster had happened, her theories would be confirmed in practice.
For the first time in the history of mankind, we could observe such a destructive event. The allocated energy would be noticed not only through telescopes, but also captured the army of satellites orbiting the Red Planet. Moreover, the NASA rovers located there would feel powerful on themselves. This did not happen, but the historical passage emphasized a potential threat to our existence. What would we do if the Earth became its goal?
Although all our forces are aimed at fighting asteroids, Plesko is interested in a more unpredictable enemy.
“Real“ hit ”will happen when it collides with a comet. This is less likely, but the danger is enormous, ”she said at the December meeting of the American Geographical Union in San Francisco.
Keep in mind that the comet was noticed in January 2013, and it flew around Mars in October 2014. Only 22 months passed. If she flew to us, then we would not have enough time for the interception mission.
“We would have to think about how to change its trajectory, which is difficult, because we do not know where it will hit,” she says.
Black cat in coal warehouse
Before you think about the reaction, you need to explain why the cometary shock is so unpredictable.
Considering the Solar System in search of wandering debris, astronomers usually scan around the equatorial plane. This is an imaginary disk around which the planets rotate. There are a couple of unstable asteroids that, due to collisions or gravitational effects in the past, go beyond the equatorial orbit. Their appearance can be calculated and, when a particularly dangerous object is seen, we have decades or even centuries to prepare for the meeting.
But the long cometary period does not concern the equatorial region. They are located far beyond the planets or even beyond the heliosphere (magnetic zone of solar influence). The Oort Cloud (the hypothetical region surrounding the solar system) resembles a projectile at a distance of one light year. Any of its objects can fly into the system at a different angle. Therefore, to investigate them is incredibly problematic.
Artistic interpretation of the passage of a comet past Mars
Comets become bright and beautiful when they come close to the Sun (heating melts ice, which is released into space in the form of a coma and tail, scattering sunlight). But having settled far away, they are completely dark and do not allow themselves to be detected.
“It's like looking for a needle in a haystack,” says Plesko. If you do not see them and do not even know the supposed place of appearance, then how to prepare?
Cannon and nuclear warheads
Plesko is developing computer code that will help simulate many different strategies to deal with these threats.
If we have time, then we can knock it off course by crushing the core with a rocket. Even the slightest blow will be enough to change its direction. This strategy will soon be tested when the European Space Agency and NASA launch a joint mission to impact an artificial earth satellite of 150 meters called “Didymoon”. The spacecraft in the Double Asteroid Redirection Test (DART) project will go to it while another device from the European Asteroid Impact Mission (AIM) is watching. This will be the first test that will show whether the kinetic effect on the asteroid. Although in 2005, NASA had already hit the comet's core in the Deep Impact mission, leaving behind a 150-meter crater in Tempel 1. But then they only wanted to look inside and not change course. But such a process takes time. And what if it is not?
From science fiction, we know that for any danger, you just need to install an atomic bomb on the object's surface and the problem is solved. But this is not a cinematic trick. True, the consequences of an explosion may be far from favorable to humanity. Instead of a single comet, we will get many of its parts that hit the entire planet. Depending on the composition of the object, one explosion can solve nothing.
But this does not negate the possibility of using nuclear weapons. You just need to do everything right. And for this it must be a lot.
Nuclear
Plesko conceived the creation of a rocket fleet equipped with nuclear warheads that are ready to launch at any minute. Of course, the probability of such an event is low. But at least we will be protected. It is necessary to understand the composition of the comet and how it will behave after the explosion. Since for the most part they consist of volatile ice, then most likely the object will simply evaporate when it is burned. It is necessary to separate its part and the Earth is saved.
“We need to mass-produce these units and update them every 50 or 100 years so that they are fully ready,” she said.
Test of nuclear weapons on the Bikini (atoll) in 1946
There are thousands of nuclear warheads and ballistic missiles around the world that are ready to fly at any time. Huge finances were spent on preparation for the Cold War. When the situation changed, Russia and the United States agreed to reduce reserves. But this weapon can be used for extraterrestrial purposes. “When death flies toward us, it would be a good idea to use a deadly weapon for the good,” suggests Pleko.
Before we put this question up for discussion, we need to find out as much information as possible about the threat. As Comet 67 / R Churyumov-Gerasimenko shows, these dusty bodies hide many secrets.
“The Oort Cloud Survey is necessary, but it is technically difficult to do,” she says. “But it’s better to start right now while we still have time.”
One day we may have a problem. And scientists insist that governments allocate funds to study this topic. And if suddenly some object decides to look at our light, now we are practically defenseless.
