Asteroid ‘2022 AE1’ was the most dangerous detected in the last decade. For a few days in January, the scientific community remained on high alert.
During a tense few days in January, an asteroid measuring approximately 70 meters became the most dangerous observed in more than a decade.
The image above shows the Asteroid 2022 AE1 observed with the Calar Alto Schmidt telescope in Spain.
Despite the Moon’s attempt to thwart observations, the asteroid is now known to be completely safe.
Expected impact in July 2023
Initial observations of the asteroid dubbed ‘2022 AE1’ showed a potential impact on Earth on July 4, 2023, not long enough to try to deflect it and large enough to cause real damage to a local area should it hit Earth.
The chance of impact appeared to increase in the first seven days of observations, followed by a dramatic week “in the dark” when the full moon overshadowed the potential impactor, preventing observations. As the Moon moved sideways, the sky darkened and ESA’s Near-Earth Object Coordination Center (NEOCC) took another look, only to find that the probability of impact was decreasing.
Since then, 2022 AE1 has been confirmed not to impact Earth and has been removed from the ESA risk list.
The highest rating on the Palermo scale
“In January of this year, we detected an asteroid with the highest rating on the Palermo scale we’ve seen in over a decade, reaching -1.5,” explains Marco Micheli, astronomer at ESA’s NEOCC.
“In my nearly ten years at ESA, I have never seen an object that posed such a high risk. It was exciting to track 2022 AE1 and set its trajectory until we had enough data to say for sure if it was going to hit us.”
Planetary defenders use the Palermo scale to categorize and prioritize the risk of impact from near-Earth objects (NEOs), combining the potential date of impact, the energy they would hit, and the probability of impact.
ESA continued to monitor the asteroid, verifying the results with NASA’s JPL, which confirmed a worrying increase in the probability of an impact from the large rock. Unfortunately, when the impact probability peaked, observations became impossible.
During a tense week from January 12 to 19, 2022, AE1 could not be seen as the weak potential impactor was overshadowed by the Moon. In addition, the asteroid was moving away in its current orbit and weakening at the same time.
Once the Moon was dark enough, the NEOCC team pointed the Schmidt telescope towards where 2022 AE1 was expected to be. With just one observation, the risk level has collapsed, approaching zero.
We now know that in early July 2023, asteroid 2022 AE1 will pass close to Earth at a distance of about ten million kilometers (+/- one million km) – more than 20 times the distance of the Moon.