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If you have seen anything online about an imminent collision between a large asteroid and our planet, worry not. A space rock is not hitting us today and its size appears to have been exaggerated.
The object, named 2009 JF1, is indeed deemed a hazardous asteroid, so it might eventually hit our planet one day in the distant future but for now we're safe.
After its discovery in 2009, it was so dim it went unobserved for years. Based on the original observation there was a small probability that it might hit our planet, possibly on May 6. Mostly it was expected to pass by a vast distance, but the uncertainty was so big it put it in the risk category, making its way onto the European Space Agency's (ESA) Near-Earth Objects Coordination Center notable risk list.
However, back in February ESA booted it out of the top 10, thanks to further observations by its Gaia satellite. This time the data showed that it was actually only around 10 meters (33 feet) across, based on the light it reflects. That’s smaller than the bolide that exploded over the Russian city of Chelyabinsk in 2013.
"[T]he asteroid has now lost its prominence in our risk list, and is relegated together with other more routine objects that pose minimal threat," ESA said at the time.
It's not even clear when it will pass us by. Astronomers hope to observe it during the upcoming days to better reduce the uncertainty of the current close passage, including distance and the precise date and time. NASA and ESA both currently have it as May 15, give or take a few days.
"Indeed, the reason for the date uncertainty is motivated by the current limited knowledge in the orbit of the asteroid," an ESA Planetary Defence Office spokesperson told IFLScience. "What we are almost certain of is that the possible impact on the 6th of May could be excluded (impact probability of just 1 / 1,700,000)."
That's one in 1.7 million, making it extremely unlikely that it will come into close contact with our planet.
We will have another astronomical visitor on Monday, too, when asteroid 2006 JF42 zooms past. At a rather larger 380 to 860 meters (1,247 to 2,822 feet) across it would do much more damage if it hit us. Thankfully it will sail past at the closest approach of 5.7 million kilometers (3.5 million miles), which is more than 14 times the distance between Earth and the Moon.
This isn't to say the risk of asteroid collision should be underestimated.
International governments and space agencies regularly take part in a tabletop exercise on how to deal with incoming space rocks as part of the bi-annual Planetary Defense Conference. Admittedly, Earth hasn't had much luck so far in deflecting the asteroid, resulting in large chunks of Europe being annihilated and New York city in ruins.
Perhaps we'll have better luck with NASA's first planetary defense mission to crash into an asteroid and knock it off course before it can reach us. NASA's DART mission launched last November and we'll find out if it works when it arrives at its destination, asteroid Dimorphos, possibly in September this year. China recently announced it is following suit with its own mission to smash into an asteroid in 2025.
Just to be clear, there are no known objects with trajectories that take out Earth currently, but it’s best to be prepared. As NASA puts it: "Planetary defense is finding asteroids before they find us."
