ESA says there are still 1377 asteroids with a real risk of colliding with Earth. Read more
Article by: Andacs Robert Eugen, on 29 June 2022, at 03:31 am Los Angeles time
The European Space Agency (ESA) says it still has 1377 asteroids on its list that are at real risk of colliding with Earth.
That, after recently eliminating one of them, 2021 QM1.
Asteroid 2021 QM1 was discovered on August 28, 2021, and has been added to the list of asteroids with a high risk of collision with Earth.
At the time, researchers believed that the asteroid would be so close to Earth in 2052 that it could collide with it.
"These early observations gave us more information about the asteroid's path, which we then projected into the future," said Richard Moissl, ESA's Head of Planetary Defence.
"We could see its future paths around the Sun, and in 2052 it could come dangerously close to Earth. The more the asteroid was observed, the greater that risk became."
But, the asteroid followed a different route than that calculated by astronomers and came much closer to the Sun than scientists thought, and became impossible to see.
"We just had to wait," explained Marco Micheli, Astronomer at ESA's Near-Earth Object Coordination Centre (NEOCC).
"But to cap things off, we knew that 2021 QM1 was also moving away from Earth in its current orbit - meaning by the time it passed out of the Sun's glare, it could be too faint to detect."
The asteroid had to get out of there, and ESA was ready for that.
"The European Southern Observatory's Very Large Telescope (VLT) was primed and ready. As soon as the 50-meter asteroid edged out from the sunlight - and if and when weather conditions allowed - ESO's VLT would focus its 8 m mirror on the disappearing rock," said the space agency.
"We had a brief window in which to spot our risky asteroid," explained Olivier Hainaut, Astronomer at ESO.
"To make matters worse, it was passing through a region of the sky with the Milky Way just behind. Our small, faint, receding asteroid would have to be found against a backdrop of thousands of stars. These would turn out to be some of the trickiest asteroid observations we have ever made".
Marco and Oliver, who also gave the above explanations, began their observations on the night of May 24, 2022, stacking their past observations one on top of the other, trying to eliminate the background stars.
The researchers found the asteroid 2021 QM1, with a magnitude of 27 being extremely dim in light, and difficult to observe. It was the exact opposite of our Sun, which has a -27 magnitude.
After extensive research, Oliver declared the object to be an asteroid, and Marco confirmed that it was the asteroid 2021 QM1 after its location.
In the end, new observations have described the asteroid as safe, with the chances of colliding with Earth now being 0%.
In any case, the list of the European space agency still has 1377 asteroids that have a high and real risk of colliding with Earth, and astronomers must monitor them all the time, so as not to happen any "surprise" in the near future.