Large asteroids are hitting Earth more often than previously thought: study

Specialists regularly assure that it is very unlikely that a large asteroid could collide with the Earth and damage it; however, recent studies show that the chances of our planet colliding with a large rock are higher than we thought.

According to James Garvin, chief scientist at NASA’s Goddard Space Flight Center, a provocative new study suggests that asteroids that could hit Earth are larger than previously thought, meaning thate The ground is at greater risk of strong impact. “That would be in the range of something serious.”

According to Science magazine, Garvin and his team used a new catalog of high-resolution satellite images to get a closer look at the eroded remains of some of the largest craters an impact formed over the last million years on our planet, in order to better estimate its true size.

For Garvin, the rings imply that the craters are tens of kilometers wider and record much more violent events.than the researchers expected. This means that each impact caused an explosion about 10 times more powerful than the largest nuclear bomb in history, enough to throw part of the planet’s atmosphere into space.

However, a new study suggests that In the last million years alone, objects four kilometers in size have fallen on the continents. and since two-thirds of the planet is covered in water, that could mean up to a dozen in total.

The work is based on a database of high-resolution satellite images from Planet. Garvin and his staff used thousands of superimposed stereoscopic images to create three-dimensional maps of four craters.. By adding data from two altitude lasers that NASA operates in orbit, including one that can penetrate tree canopy, they got maps with a resolution of 4 meters.

Items that clearly had nothing to do with hitting have been removed from the maps. They then applied an algorithm that looks for circular patterns in the topography. For small single craters, he invariably determined the apparent edge of the crater.e. But in thousands of tests conducted on the four largest craters, the algorithm often identified an edge-like structure well beyond the accepted edge.

Other experts doubt study

Science consulted various asteroid experts doubted the results achieved by Garvin’s study. Impact researchers are wary of the circles Garvin and his colleagues have drawn on maps, mainly because they challenge other impact estimates.

“I’m skeptical,” says Bill Bottke, a planetary dynamics specialist at the Southwestern Research Institute in Boulder, Colorado. “I want to see so much more before I believe it”, he told Science.

Brandon Johnson, a planetary scientist at Purdue University, says that for the results to be credible, the team will need to collect more evidence.

First, Johnson draws attention to climate change caused by impacts of this magnitude, which, according to Garvin, should have left their mark on ice cores, ocean or lake sediments. In second place, explorers must visit the sites of the rings to find deformed rocksc and gravitational variations that would indicate the true edge of the crater.