2020 GQ, the asteroid that grazed the Earth this Sunday, August 16, broke a small record. With less than 3,000 kilometers, we had never seen an object pass so close to our planet without touching it.
The information took everyone by surprise, including astronomers around the world. This Sunday, August 16, shortly after 6 am, an asteroid grazed the Earth, and it was not a passage like any other. 2020 HQ – that’s its name – approached about 2,950 kilometers from the ground, over the Indian Ocean. To our knowledge, no object had come so close to us. For example, this corresponds more or less to the distance between Paris and Cyprus. It’s also 100 times closer than the Moon, which orbits more than 380,000 km from us. He thus beats the record of 2011 CQ1, which had passed about 5,500 kilometers from the surface.
Newly-discovered asteroid ZTF0DxQ passed less than 1/4 Earth diameter yesterday, making it the closest-known flyby that didn’t hit our planet.@renerpho
Simulation: https://t.co/a81R100OwV
Higher-res GIF: https://t.co/4Wxn0YNpVb pic.twitter.com/SMtVRbjYOA— Tony Dunn (@tony873004) August 17, 2020
It must be said that astronomers hadn’t even seen him approaching – nor did they spot him when he flirted with our atmosphere at over 12 kilometers per second. It took several hours to spot this object the size of a Cybertruck from Tesla. Fortunately, 2020 HQ still had a margin before it hit the atmosphere. And even if he had come closer, it probably wouldn’t have had any consequences. Indeed, its small size suggests that it would not have survived its passage through the atmosphere. It would have fragmented very quickly before burning, without constituting any danger.
But this episode is a reminder of how crucial it is to scan space for these NEOs. And the least we can say is that they are very numerous! Among them, not all are necessarily peaceful visitors like 2020 GQ: our cosmic neighborhood could well harbor one or more particularly threatening mastodons.
In 2013, a much larger and faster meteorite (about twenty meters for more than 10,000 tonnes launched at 20 km / s) ricocheted off the atmosphere above the Urals. The shock wave caused extensive material damage. More than 1,500 people were also injured, in particular by broken windows. Imagine the damage that could cause an even more massive NEO, like the famous Apophis. In this specific case, the NASA concluded that the chances of colliding with this iron monster were low… but there are even more massive ones lurking all over the cosmos.
To avoid being at the mercy of these cosmic shells, several solutions are being considered. NASA, for example, is working on the mission D.A.R.T (for Double Asteroid Redirection Test). His goal: to send a “kinetic impactor”On boarding a potentially catastrophic asteroid to deflect it and save the planet. Let’s just hope this doesn’t happen anytime soon. Episode 2020 GQ reminded us once again that before thinking about diverting these large stones, we must first be able to spot them. Hopefully the program Sentry, which analyzes the likely impacts, has all the necessary information. Fortunately, it is not tomorrow that we will have to tremble. Right now, the most credible candidate for impact is 2010 RF12, with a 4.7% chance of hitting Earth… between 2095 and 2119.
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