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Asteroid simulators show what could happen to Earth without NASA’s DART

As NASA’s asteroid-deflection DART mission nears its target, simulators show what could happen to Earth in the event of an impact and demonstrate the importance of research into planetary defense protocols.

On Monday, the Double Asteroid Redirection Test (DART) spacecraft is expected to deliberately crash into a 530-foot-wide asteroid called Dimorphos at a speed of nearly 15,000 miles per hour. The goal is to demonstrate that a spacecraft can deflect an object that could pose an impact threat to Earth.

Dimorphos is a moon of the larger asteroid Didymos, neither of which poses a threat to our planet. But DART is the world’s first large-scale mission to test Earth’s defense technology against an asteroid or comet collision and will help scientists prepare for potential future dangers.

The chances of a potentially dangerous NEO or near-Earth object – an asteroid or comet in our cosmic neighborhood – hitting our planet anytime soon are remote. But there is a good chance that a collision will occur at some point in the future. If and when such an event occurs, the consequences for humanity could be devastating, depending on the size of the impacting object.

“Basically, an object 100 meters in diameter is likely to create a crater about 1 kilometer in diameter on Earth,” said Gretchen Benedix, professor of geology and geophysics at the Center for Space Science and Technology and the Curtin School of Earth and Planetary Sciences in Australia. University.

“If it hits a densely populated area, it could be quite severe but overall not devastating to the region or the Earth. An object of this size is estimated to hit Earth every 10,000 years,” Benedix said. Pleasemynews.

She continued: “Something the size of the object – about 10 kilometers or 7 miles in diameter – which created the Chicxulub crater, which is thought to be associated with the extinction of the dinosaurs and a nuclear winter which lasted two years, is estimated to occur every 100 million years, so if the last one was 65 million years ago, we have some time for that.

A simulator, developed by researchers at Imperial College London and Purdue University, shows just how devastating a potential asteroid impact could be. The tool estimates the environmental consequences of an impact event on Earth.

The first version of the tool is a simple text interface where you enter some parameters, such as the size and speed of the object. The simulator provides a commentary of what you might feel at a given distance from impact.

The team has also created a newer version of the tool, which allows users to plot potential effects on a mapping tool, similar to Google Earth.

“One is good if you want to know what’s going to happen to you at a particular place, but the other is good for showing you how big the damage would be,” said Gareth Collins, professor of planetary sciences at the Imperial. and co-creator of the tool.

The tool calculates the five main environmental effects of an asteroid impact that could occur. The first of these is thermal radiation.

If an asteroid or comet strikes with sufficient velocity, it will create a fireball – a plume of vaporized rock and heated air that engulfs the crater and the site closest to the impact. Since the average impact velocity on Earth is around 20 kilometers per second, you would typically see one of these fireballs.

“If you’re in the crosshairs of this, so if it’s not below the horizon, then you’re probably going to suffer the most extreme consequences,” Collins said.

Impacts will also produce a shock wave, which is essentially the shock wave produced in the atmosphere by the materials thrown out of the crater and the energy released by the collision.

It’s like an explosion in the atmosphere, which forms a very strong air pressure wave that travels rapidly away from the impact site and can, if you’re close enough, be powerful enough to knock down trees or break windows. It can also destroy vehicles and buildings in more extreme cases.

If the impactor hits the earth, it will form a crater, which is basically a hole in the crust. This is produced by throwing material, mostly rocks and dust, out of the crater, what scientists call ejecta.

These ejecta can travel great distances and land on earth as a blanket of debris. This blanket is quite thick near the crater and thins out as you move away.

“Depending on how far away you are, a certain thickness of dust will land on top of you. And in the larger impacts, that can be significant,” Collins said. “The dust is very fine, so it takes a long time to settle in the atmosphere.

“When it’s in the atmosphere, it can block sunlight, and that’s actually what we think was the main environmental consequence that led to the dinosaurs becoming extinct – that there was a lot of dust very thin in the atmosphere for a long time, blocking sunlight and cooling the global climate,” he said.

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