On January 9, an asteroid between 15 and 34 meters in diameter passed just 200,000 kilometers from Earth at a speed of 16 kilometers per second. It seems like a lot, but if we take into account that it is more or less half the distance between the Moon and our planet, it could be said that it brushed past us. No one knew of its existence until two days before, when it was detected by scientists from the Catalina Sky Survey program at the University of Arizona, who scan the sky in search of these types of objects.
For experts, whether a large space rock reaches the Earth’s surface is not a question of whether it will happen or not, but of when it will happen. Bodies under 25 meters tend to disintegrate in the atmosphere , but larger ones can cause significant damage. Thus, about 50,000 years ago, one between 30 and 50 meters long fell in what is now northern Arizona. The impact created a huge crater, perfectly visible today, about 1,200 meters in diameter and 170 deep.
Although these types of events are very rare, they continue and will continue to occur. For example, in 2013, a space bolide that exploded in the sky near Chelyabinsk in Russia generated 30 times more energy than the atomic bomb that devastated Hiroshima; the blast wave caused extensive damage and nearly 1,500 people were injured . The object that originated it all was relatively small, only about 18 meters.
Now, an international team of researchers led by the Higher Council for Scientific Research (CSIC) has presented a study that examines a possible way to avoid it. In an article published in The Astrophysical Journal , these experts explore the effects that the impact of a kinetic projectile, that is, without an explosive charge, would have on an asteroid. The idea is to elucidate whether in this way it would be possible to divert one of these objects, which can constitute very valuable information in the event that, one day, it is necessary to do so. To do this, they have focused precisely on the one in Chelyabinsk. Thus, they have determined that, to a large extent, the success of this initiative would depend on the physical properties of the asteroid, such as its density, composition and internal structure .
“The study of the chemical and mineralogical composition of the Chelyabinsk meteorite allows us to know fundamental details of the compaction processes due to collisions that the asteroids have suffered. The results of this work are very relevant for a possible mission in which it is want to efficiently divert one of them “, says in a statement the CSIC researcher Josep María Trigo, from the Institute of Space Sciences, who has participated in the project.
Scientists have used a nanoindenter, a device equipped with a tiny piston topped in a diamond head that generates continuous pressure and small indentations in the materials that made up the space rock – the same ones that make up most of those that pose a threat. for our planet – and allows us to know its hardness, elasticity and resistance to fracture. According to the researchers, thanks to the performance of these experiments, we are closer to successfully facing an encounter with asteroids.
Image: NASA
