The 70-meter large asteroid 2022 AE1 was discovered in early January. This object appeared to pose a potential threat to Earth and even climbed to hazard level 1 on the Torino Scale and -0.66 on the Palermo Scale. Fortunately, there is no longer a threat.

Asteroid 2022 AE1 was discovered on January 6 by the Catalina Sky Survey. A day later it confirmed automatic Asteroid Orbit Determination (AstOD) system that there was a small chance of an impact. “We were surprised to see asteroid jump straight to -1.5 on the Palermo Scale, which is quite rare,” said Luca Conversi, manager at NEOCC. “Several times a year we see that an object is in a high risk class, but -1.5 is exceptionally high.”

What are the Palermo and Torino scales?
The scale of Torino is a way to assess the impact risk of asteroids and comets. The Torino Scale is determined by two factors: the probability of impact and the size of an asteroid. So far, only one hazard level above 3 has been assigned, namely level 4 to asteroid Apophis in 2004. This warning has since been withdrawn. The Palermo scale is more complex and calculates the relative risk of an impact by, among other things, looking at the time interval until the possible impact, the kinetic energy released during a collision and the probability of the impact. This scale starts at -5 and goes up. If the danger level exceeds 0, there is a high probability of impact.

When 2022 reached AE1-1.5 on the Palermo Scale, several telescopes were activated to observe the near-Earth plane. More observations usually ensure that the trajectory of an object can be calculated better and that the chance of impact decreases considerably. But not in the case of 2022 AE1. On January 10-11, the chance of impact was smaller than ever, at 1 in 1500, and the danger level rose to -0.66 on the Palermo scale.

A photo of asteroid 2022 AE1 taken by the Calar Alto Schmidt telescope on Jan. 19.

During the week of January 12 to January 19, the astronomers were unable to make any observations. The crescent moon threw a spanner in the works. Our natural satellite was only on January 14th three degrees away from the asteroid, making the object barely visible in the bright moonlight.

The moment the moonlight was dimmer, the scientists were able to continue observations. One observation was enough: the asteroid no longer appeared to pose a threat. “If the orbit of 2022 AE1 had remained uncertain, we would have continued to track the object,” said NEOCC scientist Laura Faggioli. “Now this was no longer necessary. Time to look for the next closer to Earth.”

What if 2022 AE1 crashed on Earth?
Fortunately, a 70-meter asteroid is not big enough to pose a threat to all life on Earth. However, a regional area would be completely destroyed. In 1908 an asteroid exploded over Siberia† This asteroid may have been the size of 2022 AE1. The force of the explosion caused trees to break off at the base of the trunk within a radius of 40 kilometers. If such a similar asteroid were to hit an inhabited area or cause a tsunami, the consequences would be many times greater. In that regard, we were “lucky” that the Tunguska Explosion took place in Siberia.

Asteroids and comets can pose a threat to life on Earth. More than 18,000 near-Earth objects have already been mapped. In discovering near-Earth objects, researchers have a clear goal in mind: to identify asteroids that could pose a threat to Earth in good time. In theory, there are several ways we can make a space rock heading toward Earth change course, but each of those ways requires us to see the rock coming well in advance.

In the case of 2022 AE1, the book is closed. On July 4, 2023, the asteroid will fly past Earth at a distance of more than 9 million kilometers.