An asteroid the size of a refrigerator came within 3,000 kilometers of Earth without scientists knowing it.
Asteroid 2021 UA1 is the third-closest asteroid that has ever approached our planet, and passes over Antarctica on Sunday at a higher altitude than the International Space Station, but lower than the communications satellites orbiting the Earth.
The celestial object had only a diameter of two meters, which means that if it had come closer to our planet, it would probably have been burned up in our atmosphere.
“The reason the planet’s bypass was so surprising was that it was behind the sun and came from the day sky, so it was undetectable before the nearest approach,” tweeted Tony Dunn, an astronomer who runs the site Orbitsimulator.
There are only two asteroids that have come closer in Earth’s history: one was the asteroid 2020 QG, which came just 1,830 miles above the southern Indian Ocean – but was also small enough not to pose a threat to Earth – and the asteroid 2020 VT4, which flew a few hundred kilometers away on Friday the 13thth.
Although these asteroids are too small to affect the Earth, the possibility that a larger asteroid could cause significant damage to the planet is one that many scientists are preparing for.
In May, Nasa conducted a simulation over the course of a week to prepare for such an eventuality, but concluded that there is no technology on Earth that could stop it from happening.
The only reaction would be to evacuate the area before the asteroid hit, but the impact zone was across large parts of North Africa and Europe.
Chinese scientists have considered launching more than 20 rockets that could stop a giant asteroid.
China’s National Space Science Center found in simulations that 23 Long March 5 rockets weighing 900 tons as they leave the planet hitting simultaneously could divert an asteroid from its original orbit by nearly 9,000 kilometers – 1.4 times the Earth’s radius.