In 2021, the asteroid 2021 UA1 came so close to the Earth that it could have easily smashed into the planet and caused a disaster. Know all about our planet’s escape.
We keep reading about asteroids flying past the Earth on a regular basis but we don’t actually realize how terrifyingly close these space rocks can get and the scale of destruction they can inflict on our planet if they smash into it. But every now and then, an asteroid gets pulled by the Earth’s gravity and gives us a glimpse of the disaster these terrifying asteroids can bring about. We all know about the Chelyabinsk incident in 2013 when a 20-meter wide meteor exploded above the Russian city and just the sonic boom was enough to break the glass of skyscrapers and cause heavy infrastructure damage in a large radius. The Earth has made a lucky escape from such asteroid strikes many times but the most recent one came last year when Asteroid 2021 UA1 came knocking on Earth’s door.
The asteroid that nearly struck the Earth and caused a major tragedy
Asteroid 2021 UA1 is a small asteroid, just 2-meters wide. But you’d be making a mistake of taking it lightly. These asteroids travel at the speed of thousands of kilometers per hour, faster than any object on Earth. For example, the fastest bullets shot from a gun can reach the speed of about 3,000 kilometers per hour, which is around twice the speed of sound. However, the average speed of an asteroid is between 20,000 – 50,000 kilometers per hour and some are even faster than that. That margin of speed packs a gigantic amount of kinetic energy in these small rocks which when smashing into another celestial body, can do the damage equivalent to a nuclear weapon.
On October 25, 2021, this asteroid came as close as just 3,047 kilometers to the Earth while passing over Antarctica. Despite its size, it could be seen as a very bright spot in the night sky with a magnitude of 1.4. This asteroid could have easily destroyed a city if it was pulled in any further by the Earth’s gravity, but thankfully its high velocity allowed it to counteract the gravitational pull. For comparison and to put things in perspective, know that the moon is 384400 km from Earth. This really shows how close this asteroid got to Earth. The International Space Station is 408 km from Earth.
Interestingly, even the scientists on Earth could not predict that an asteroid would be coming this close to the Earth. The reason behind it was that the space rock was coming in from the direction of the Sun. The first time it could be observed was just four hours before it made its closest approach. So, if it was a larger asteroid which struck the Earth, despite our planetary defense systems, we would probably not be able to do anything before it destroyed the planet.