An analysis of the distribution of near-Earth objects, carried out using the DECam camera mounted on the 4-meter Blanco telescope of the Inter-American Observatory Cerro Tololo, located in Chile, showed that the number of near-Earth objects up to 20 meters in size reaches 3.5 million.
NEO - Near-Earth Object, an object of the solar system, the orbit of which passes in close proximity to the Earth.
If a large asteroid, about ten kilometers in size, crashes into the Earth, it can lead to the extinction of all life on the planet. However, the fall of smaller asteroids, for example, with a size of the order of several tens of meters, is also accompanied by quite tangible consequences: for example, when the famous Chelyabinsk meteorite fell, an explosion was observed with a power comparable to the power of 10 atomic bombs exploded over Hiroshima. Therefore, the study of the distribution of such asteroids is an important scientific problem, the solution of which will help to calculate the probability of falling of such objects on the Earth's surface with higher accuracy.
In a new study, a group of astronomers led by Lori Allen, director of the Kitt Peak National Observatory, USA, estimated the number of NEOs comparable in size to the Chelyabinsk meteorite. “In orbit around the Earth, there are approximately 3.5 million NEOs over 10 meters in size - a population about 10 times smaller than estimates from previous studies. Approximately 90 percent of these NEOs are in the Chelyabinsk range of sizes, that is, in the range from 10 to 20 meters, Alain explained.
These new findings provide interesting insights into the likelihood of NEOs from this size range entering Earth. To explain the frequency of falling objects of this size on the surface of the planet, known to scientists from previous studies, with a smaller number of them in orbit, it is required that the probability of their falling be greater than the probability of falling NEO of other sizes. This explanation can be made on the basis of the assumption that NEOs 10-20 meters in size are more common in groups that are clouds of debris of a larger body, and the probability of a fragment from such a group hitting the Earth is higher than the probability of hitting a single NEO, Allen said. and his team.