For many people, they are the danger that comes from the darkness. Asteroid impacts can bring death and devastation. Experts have long been scanning the sky to see dangerous chunks from space in time.
The danger of asteroid impacts is omnipresent, and international space agencies are increasingly turning their attention to the chunks from the far reaches of our solar system. Defense against these remnants of planetary formation has also long since ceased to be science fiction. The bombardment of asteroids is not only the subject of disaster movies, but is on the minds of researchers and is soon to become reality for the first time.
According to experts, however, there is no need to fear disaster from outer space at present. Really big chunks are not on a collision course with our home planet. “There is no reason to panic,” says the asteroid expert of the European Space Agency Esa, Detlef Koschny, on the occasion of Asteroid Day on June 30. However, there can always be surprises. “There are many objects out there that we don’t even know about yet.”
Most asteroids are irregularly shaped, though a few are nearly spherical, and they are often pitted or cratered. Learn more about the Asteroid types with Margo Kerman! #AsteroidDay pic.twitter.com/CxYxMkRSpG
— Kerbal Space Program (@KerbalSpaceP) June 26, 2021
2013: Asteroid hits Chelyabinsk
In 2013, a 20-meter asteroid came out of nowhere in the Russian megacity of Chelyabinsk and wreaked havoc. Without any warning, the blast wave injured about 1500 people mostly by breaking windows. An explosion of a chunk of this size releases an energy of 500 kilotons of the explosive TNT – the Hiroshima bomb had 15 kilotons.
On June 30, 1908, an asteroid explosion also occurred in Russia. In Siberia, the shock wave swept away millions of trees over an area almost as large as the Saarland. Because of this natural disaster, the United Nations proclaimed June 30 International Asteroid Day in 2016.
According to Koschny, from a size of 50 meters one must think about an intentional deflection. Asteroid “Apophis” with a diameter of about 300 meters was such a candidate. For a long time it was believed that the chunk had collision potential with Earth in 2068. In the meantime, the asteroid has been removed from Esa’s risk list.
If an asteroid is headed toward Earth, Harris says you don’t have many options. That would require trying to deflect its path with a series of nuclear warheads. “But we would know that centuries in advance. We’re sure there’s nothing in the sky that could hit the Earth that’s larger than a kilometer.”
Prepared for an emergency
Nevertheless, the space agencies want to be prepared for possible dangers from space. The sky is already being scanned, and now Esa and Nasa are launching a joint project to change the orbit of an asteroid for the first time in the history of space travel. The U.S. probe “Dart” is to hit the smaller chunk of a double asteroid 150 million kilometers away in 2022.