Scientists reassure after an intensive manhunt: asteroid 2021 QM1 on closer inspection poses no threat to Earth this century.

For months, a looming space rock topped astronomers’ list of risks. Asteroid 2021 QM1 could be on a collision course with Earth and could hit our planet on April 2, 2052. Today, however, on International Asteroid Day, scientists come with some good news: the danger seems to have passed. At least in this century…

International Day of the Asteroid
Today is International Asteroid Day; an annual day of action, created to raise awareness about the danger and risks of asteroids. It’s not for nothing that International Asteroid Day takes place on June 30. On June 30, 1908, the Tunguska explosion took place near the Stony Tunguska River in Siberia. As a result of the explosion, trees within a radius of 30 to 40 kilometers broke off at the base of the trunk. The cause of the explosion is still much speculated, although it is strongly suspected that it was the result of an asteroid.

Asteroid 2021 QM1 was discovered on August 28, 2021 by the Mount Lemmon Observatory, located in the Santa Catalina Mountains in the US state of Arizona. At first, nothing seemed to be wrong. Every night, about a dozen new asteroids are discovered in our cosmic backyard, which are then routinely monitored using various telescopes. But the longer researchers followed 2021 QM1, the more concerned they became.

Apr 2, 2052

Astronomers concluded that there was a real chance that 2021 QM1 would hit Earth. And on April 2, 2052 to be exact. “The first observations gave us more information about the asteroid’s course,” said researcher Richard Moissl. “This then gave us an idea of ​​his future path. From this, we concluded that the asteroid could come dangerously close to Earth in 2052. Moreover, the longer we observed it, the greater the chance became.”

(Im)perfect cosmic alignment

However, the asteroid then briefly disappeared from the researchers’ field of view, due to a so-called (im)perfect cosmic alignment. As seen from Earth, 2021 QM1 moved closer and closer to our sun, making it impossible to observe for months due to the glare of our parent star. “We just had to wait,” said researcher Marco Micheli.

The orbit of asteroid 2021 QM1, where it disappeared from the field of view of astronomers due to an (im)perfect cosmic alignment. Image: ESA


The team knew when 2021 QM1 would resurface. So they kept ESA’s Very Large Telescope at the ready to get a closer look at the possible near-Earth proximity. “We only had a short time to study the asteroid,” said researcher Olivier Hainaut. And to make matters worse, the asteroid also passed right in front of the Milky Way. This meant that we would have to find our small, faint asteroid against a background of thousands of stars. It was certainly one of the most difficult sightings we have ever made.”

2021 QM1 seen against a backdrop of thousands of glittering stars. The red crosses indicate the orbit of the potentially dangerous asteroid. Image:
ESO/O. Hainaut

Ultimately, the researchers managed to find 2021 QM1, the faintest asteroid ever observed. For your imaging, the light from 2021 QM1 is 250 million times dimmer than that of the faintest stars visible to the naked eye from a dark spot.

Danger gone

Thanks to the new observations, the team was then able to further refine the path of the potentially dangerous near-Earth. And we can breathe a sigh of relief. Because 2021 QM1 does not appear to be on a collision course with the earth. At least not in the next century.

It means that the danger for 2021 QM1 has passed. But we haven’t fully secured ourselves with that. In the meantime, a million asteroids have already been discovered in our solar system, of which almost 30,000 will skim past Earth. This is also just the tip of the iceberg; according to astronomers, there are probably also many (smaller) space rocks that we do not have in our sights. Scientists are therefore constantly looking up and scanning the night sky for potentially dangerous nearers, so that we will know well in advance if one is headed for Earth at an emergency speed.