It was devastating in its proportion, circumscribed by its impact on the atmosphere. It could have been disastrous had it been closer to the ground. It all happened on February 15, 2013. Nobody predicted the arrival of the Chelyabinsk meteor – the biggest asteroid to hit Earth in over a century. Despite being a relatively small rock, it made a huge impact, especially on the pride of those who thought we were safe from the destroying asteroids. We’ve been lucky!
Exploded without warning, wreaked havoc and showed that we are defenseless
Just after sunrise on a sunny winter day, a 20-meter, 13,000-ton asteroid hit the atmosphere over the Ural Mountains in Russia at a speed of over 18 km/s.
The relatively small rock exploded in the atmosphere at an altitude of 30 km, releasing an energy of about half a megaton (the equivalent of 35 Hiroshima bombs). Two minutes later, the shock wave hit the ground damaging thousands of buildings, breaking windows and injuring around 1500 people due to shattered glass.
Hidden in the glare of our Sun are an unknown number of asteroids, on paths we don't know, many of which may be heading towards Earth and we just don't know.
Asteroids the size of the Chelyabinsk meteor hit Earth approximately every 50-100 years. Injuries from air blasts or similar events can be prevented if people are made aware of an impending impact and its anticipated effects. With prior notice, local authorities could advise the public to stay well away from windows and glass.
ESA's NEOMIR mission will detect asteroids like Chelyabinsk coming from the same region in the sky as the Sun, filling a vital gap in our current abilities to predict and plan for hazardous impacts.
Explain Richard MoisslHead of Planetary Defense at ESA.
Chelyabinsk… look up
Of course, there is also the risk of an even larger asteroid hitting Earth from the dayside. Such a scenario is less likely, as the larger the asteroid, the smaller the number of these objects in the Solar System and the easier their detection. In fact, almost all asteroids larger than 1 km have been discovered.
But as the dinosaurs would tell us, if they could, when a massive asteroid strikes, it does unimaginable damage. Fortunately, as NASA's DART impact demonstrated and ESA's Hera mission will continue to expose, asteroid deflection is a real possibility.
So how do we make sure we're prepared? A NEOMIR will be located at the Lagrange point “L1” between the Earth and the Sun. Undisturbed by our planet's atmosphere, your infrared telescope will be able to detect asteroids of a size equal to or greater than 20 meters and currently hidden amongst the glare of the Sun.
With enough warning, an asteroid impact is the only natural disaster we can avoid.
