Zero risk does not exist, but the chances of being hit by debris from the ERS-2 satellite, precipitated into the atmosphere on February 21, 2024, are infinitesimal.
The space event of the week will undoubtedly be the moon landing attempt by the private American lander Intuitive Machines 1. It will be Thursday February 22, 2024. Before that, there will be another incident which will undoubtedly attract your attention: the voluntary fall of a European satellite, ERS-2, after sixteen years of good and loyal service.
The machine must be deliberately thrown against the earth’s atmosphere during the day of Wednesday February 21. The maneuver carried out by the European Space Agency consists of destroying it at high altitude, taking advantage of air friction. The operation is not trivial, especially since ERS-2 weighs 2.3 tonnes.
The breakup of ERS-2 must occur above the Earth at an altitude of around 80 km. Most of the debris should burn on this occasion, without ever reaching the surface of the globe. But the ESA admits that there are a few fragments that can still survive this furnace and hit the ground.
The possibility that some ERS-2 residues hit the ground does not mean that there is a risk for populations. In fact, ESA projections suggest that in this scenario, this rubble will end up in the ocean — after all, nearly 70 percent of the earth’s surface is covered by oceans.
An infinitesimal risk of collision
Of course, it is worth remembering that zero risk does not exist. But the probability of being hit by space debris is extremely low. We are talking about an annual risk of 1 in 100 billion for a person, according to the ESA. The BBC even puts forward an even slimmer probability, of the order of one in a trillion.
To put this into perspective, the European Space Agency points out that the risk of being hit by falling space debris is 1.5 million times lower than the risk of being killed in a domestic accident. It is 65,000 times lower than the risk of being struck by lightning. And it is 3 times lower than the risk of getting hit by a meteorite.
There is a greater chance of hitting a meteorite than space debris
In fact, this peril is so rare that the only recorded case is that of a woman living in the United States, Lottie Williams.
This Oklahoma resident is to date the only person to have been hit by a space fragment re-entering the atmosphere. It was in 1997. It was a piece of metal about fifteen centimeters long from a rocket that had disintegrated. She was hit in the shoulder, but the coin fell so slowly that she was not injured.
Perhaps there are other cases, but they have not been documented. There have also been no deaths caused by space junk. Under these conditions, it is reasonable not to unduly modify your plans for Wednesday February 21. You can move outside, the sky won’t fall on your head. The danger is infinitesimal.
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