ESA rules out 2052 impact by asteroid 2021 QM1; removes space rock from 'risk list'

The European Space Agency (ESA) recently confirmed that a near-Earth asteroid, which initially posed a threat to our planet, is no longer a risk. Named ‘2021 QM1’, the 50-m-wide asteroid's trajectory and initial observations suggested that it would strike on 2 April 2052 and was put on the 'risk list'. However, follow-up observations and analysis of the faintest asteroid ever observed have confirmed that there is no possibility of an impact on the said date and thus, it has been removed from the dreaded list.

What did the follow-up observations reveal?

The asteroid was discovered on 28 August last year by the Mount Lemmon Observatory, located north of Tucson, Arizona and since a dozen new near-Earth asteroids are discovered every other night, nothing came off as suspicious for the scientists. But Richard Moissl, ESA’s Head of Planetary Defence, started noticing a concerning case as he continued studying the newly discovered space rock. 

"These early observations gave us more information about the asteroid’s path, which we then projected into the future", Moissl said in a statement. "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". 

It is worth noting, however, that these conclusions were based on a few nights of observations, which is why many asteroids make it to ESA's 'risk list' so easily. In the following days, the asteroid turned hard to observe due to the sun marching in between the asteroid's path and that of the Earth. It was when the space rock emerged again, that astronomers observed it with the Very Large Telescope (VLT) and revisited the asteroid's path. In the process, VLT captured the faintest picture of the 2021 QM1. Interestingly, this asteroid was approximately 250 million times fainter than the faintest stars visible to the naked eye from a dark spot.

(Asteroid 2021 QM1 photographed by the VLT; Image: ESA)

As mentioned above, the follow-up study refined the asteroid's path and helped astronomers confirm that the asteroid has no impact probability in 2052. Notably, the 'risk list' still contains 1.377 near-Earth asteroids. What's more, is that over one million asteroids have been discovered in the Solar System and almost 30 000 of them pass near Earth.