In 1908, the air burst of a meteoroid crushed 80 million trees near the Podkamennaya Tunguska River (Siberia). An impact crater was never found, since, according to the story, the celestial body disintegrated at an altitude of 5 or 10 kilometers. What would have happened if the almost 100 meter long rock had hit the surface of the Earth? Scientist Lubin is not willing to trust to luck again and has devised a planetary defense system to deal with any dangerous asteroid or comet.
Physics professor at the University of California Santa Barbara, Philip Lubin, and co-investigator Alexander Cohen recently featured in the journal ‘Advances in Space Research’ his new creation: PI, which stands for spray it (Spray it). Basically, it consists of using technology to ‘pulverize’ the asteroid in question into smaller debris that would then burn up in the Earth’s atmosphere.
Paradoxically, his thesis rests on the idea of let the Earth receive the impact of the celestial rock, instead of trying to divert its route as a large part of the scientific community has proposed until now. The difference lies, in this case, in that your system would disassemble the threat into smaller pieces, mitigating the damage that it may cause. In fact, according to their study, these large “pieces” – the size of a conventional house – would be absorbed by energy from the atmosphere without ever hitting the ground.
“In short-intercept scenarios, asteroid fragments of a maximum of 10 meters in diameter allow the Earth’s atmosphere to act as a ‘beam discharge’ where the fragments burn up in the atmosphere or burst in the air, with the main channel of energy entering spatially and temporally decorrelated shock waves»explain the study.
How to blow up the asteroid?
After theory comes practice. And attacking a celestial object in full motion does not seem easy… To do this, researchers have developed an “impactor” that is not only kinetic, but also explosive.
Through a system of penetrating rods – 10 to 30 cm in diameter and two to four meters long – placed in the path of the asteroid to “cut and cut” the threatening object, PI would manage to fragment the core of the asteroid or comet when it collides with them at extreme speed.
Researchers explain the difference: Imagine that “A 500-kilogram piano was thrown at your head from a distance of one kilometer or 500 kilograms of foam balls fell on you from the same distance”. The balls might do some damage, but definitely they wouldn’t kill you. His idea was awarded by the POT in the NIAC program (Innovative Advanced Concepts), which promotes and supports visionary ideas that can transform future missions.
Just 10 days before impact
Months or years in advance, a ‘kinetic impactor’ can be sent to redirect an asteroid. But what if this system fails? Or if we find out too late that an asteroid is approaching Earth? It is in this scenario that Lubin’s plan becomes vitally important. “The great advantage of this approach is that it allows for terminal defense in short alert times and target distance mitigation. when orbital deviation is not feasible», Lubin explains.
Based on his calculations, smaller targets, like the meteor from Chelyabinsk (2013- 13 wounded), could be intercepted minutes before impact using smaller launchers similar to those intercontinental ballistic missile interceptors.
An asteroid like Tunguska it could be intercepted five hours before its impact. While targets that pose a more serious threat, such as Apophis (it was speculated that it could impact the Earth in 2029), they could be intercepted only 10 days before the impact. “Until now, humanity has been spared a large-scale catastrophe such as our previous inhabitants of the planet suffered, but relying on being ‘lucky’ is a bad long-term strategy”said Philip Lubin in 2021.
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Reference article: https://www.20minutos.es/noticia/4966168/0/como-detener-el-impacto-de-un-asteroid-un-cientifico-propone-pulverizarlo-en-pequenas-partes/