Sunday 05 April, 2020

Können wir Asteroiden von Kurs ablenken?

Veröffentlicht: 28 November 2016 Monday, 06:34  PM

Können wir Asteroiden von Kurs ablenken?

Bonn, Non 28 ( - ESA and NASA are working together on a new mission. You want to find out if you can distract an asteroid from its course by shooting a space probe at him.

Asteroids - large clumps of rock and metal that run through the universe - are able to trigger a disaster on Earth. A small asteroid can smash a whole city, a big one could even mean the end for all of us. Patrick Michel from  Observatoire de la Côte d`Azur  in Nice: "An asteroid is a small stone from the remnants of matter that formed our planet. Most asteroids are located in the  asteroid belt  between Mars and Jupiter. But some have runways that cross the earth`s trajectory. And these asteroids are a threat to us. "

A limited danger, admittedly, because an asteroid impact of considerable extent happens every ten thousand years or less frequently. Nevertheless, it is a threat that needs to be taken seriously, emphasizes Michel: "Even if there are few impacts: As with the lottery, the probability of winning is low - but some win."


Space organizations are tackling the problem. Recently, two missions, one American and one Japanese, broke out to asteroids to take samples. And ESA and NASA are now planning something never before seen in a community project called AIDA - the  Asteroid Impact and Deflection Assessment  mission.

 "" AIDA ": http: // is in my opinion the boldest project after Rosetta. The plan is to test a defusing technique called kinetic impactor. We want to test whether we can redistribute asteroids, "explains project manager Ian Carnelli.

This is planned: The ESA space probe AIM starts in 2020 to the Didymos asteroid system, in which a large asteroid is surrounded by a small asteroid called Didymoon. AIM observes this moon. After six months, NASA`s space probe DART is to be approached and hit Didymoon. While AIM is recording what happens.

Spectacular impact after a flight into the unknown


"The impact will be spectacular," says Carnelli, "DART arrives at six kilometers per second. AIM is a hundred kilometers away to be safe. DART will change the orbital velocity of this moon around the main asteroid by about half a millimeter per second by its impact. This is really little. But it does take about ten minutes to change over eleven hours, and we can measure this accurately. "

Until then, however, a lot has yet to be explored. At the ESA Technical Center in the Netherlands, the engineers simulate the situation that the AIM space probe will find when it arrives at the asteroids. They know that the small Didymoon circles around the larger asteroid - but much more is not. "According to our observations, we have an approximate idea of ​​what it looks like. But we are not sure. And we will not be sure before we get there, "admits control engineer Irene Huertas. On the basis of a model of the twin sasteroids, she tries to align the camera with the AIM space probe so that she can accurately film the impact. "We can take different scenes with darker asteroids, brighter asteroids, stony or smooth surfaces, or a combination of both. A darker moon and a bright main body. After the impact, AIM will take additional pictures. She will observe what happens. As the moon looked before and after the serve. And to what extent we have turned the little moon over. "

This double steroid system was chosen because it is close to the earth, but not a hazard. But asteroids in the size of the small moon could have devastating effects when impacting the Earth. Ian Carnelli: "Didymoon has a diameter of about 163 meters. This is a very interesting quantity, because it is representative of a type of asteroid, which would damage in any case, if it collides with the earth, no matter where it strikes. In the middle of the sea, he would trigger a tsunami, on land he would meet populated territory. Therefore, it is a very important asteroid type. "

Patrick Michel emphasized that this was a real experiment. There are simulations, but no one knows whether humans can redirect an asteroid: "The reaction of an object to an impact depends strongly on its inner structure. A metal rod reacts differently than a sponge. Thanks to AIM, we know exactly what our object is, and can better evaluate the computer simulations and interpret the result of the impact. "

The scientists hope, after this experiment, with further defensive maneuvers on asteroids to perfect their technique so that they are equipped for the emergency. Michel: "The danger of asteroids should really be taken into consideration. Even if we do not have to worry about them in the short term, they are the only natural threat to be predicted and we can face. "


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