Discover an asteroid Late last year, the public interest continues, as the chance that the planet Earth will strike less than eight years from now is increasing.
Two weeks ago, when Ars first wrote about the asteroid, named 2024 YR4, the NASA’s Center for Near Earth Object Studies estimated a 1.9 percent chance of impact with the Earth in 2032. NASA’s most recent estimate has the likelihood of a strike increasing to 3.2 percent. Now it is not very high, but it is not zero.
Of course, the prospect of a large ball of rock ten meters over the planet is a bit alarming. It is large enough to cause localized devastation near the impact place, probably on the order of the Tunguska event of 1908, which looked about 1,295 square kilometers from the forest in the remote Siberia.
To understand why the chance of Nasa is changing and whether we should be concerned about 2024 YR4, ARS related to Robin George Andrews, author of the recently published book How to kill an asteroid. Good timing with the publication date, right?
ARS: Why does the impact increase?
Robin George Andrews: The track of the asteroid is not very well known at the moment, as we only have a limited number of telescopic observations. But although the rocks zipper from the earth, certain telescopes still succeed in spying it and expand our knowledge of the asteroid’s orbital bow around the sun. The odds have varied in both directions over the past few weeks, but in general they have risen; This is because the amount of uncertainty stars has shrunk about its true orbit, but the earth still has to fall completely out of the zone of uncertainty. As a part of the remaining uncertainty, the earth is taking more room, so the odds are now on.
Think of it like a ray of light coming from the front of that asteroid. That ray of light shrinks as we get to know the orbit better, but if the earth still has to fall out of the beam, it takes in proportionally more space. So, for a while, the impact of the asteroid increases. It is very likely that the earth, with sufficient observations, will eventually fall out of the shrinking ray of light, and the impact can suddenly fall to zero. The alternative, of course, is that they will rise almost 100 percent.
What do we learn about the destructive potential of the asteroid?
The damage it could cause would be localized in a coarse city -sized area, so if it hit the middle of the ocean or a large desert, nothing would happen. But it can be a city waste, or very completely destroyed, with a direct hit.
The key factor here (if you had to choose one) is the mass of the asteroid. Each time the asteroid becomes twice as long (suspected of being about spherical), it brings 8 times more kinetic energy. So if the asteroid is at the smaller point of the estimated size range – 40 meters – then it will be as if a small nuclear bomb explodes in the air. At that size, unless it is very iron -rich, it would not survive its atmospheric dive so that it would explode in the air. There would be a modest structural damage under the explosion, and minor to moderate structural damage over ten kilometers. A 90 -meter asteroid would, whether on the ground or not, be more than ten times more energetic; A large nuclear weapon explosion then. A large city would be severely damaged, and the area under the explosion would be destroyed.