Killer space junk falling from the sky! Time to start worrying for your safety?

tech.hindustantimes.com:

In the past few days we've read about two separate incidents of space junk hurtling back to Earth in unexpected places including one from an out-of-control Chinese rocket and then there was another one from SpaceX. Though the 23-tonne Long March 5B booster crashed to Earth over the Indian and Pacific oceans, it had left many readers frightened about the possible consequences. The incident sparked questions about the threat of space junk falling on people. Here we have explained what actually scientists and researchers say about it.

A recent study by scientists at the University of British Columbia in Vancouver suggest that there was a 10 percent chance that an out-of-control rocket or spacecraft could kill someone. Believing that each re-entry spreads debris over an area of ten square meters, researchers calculated that there is a 10% chance of one or more casualties over the next decade, on average. The study, published in Nature Astronomy, has calculated the chance of casualties from falling space junk over the next 10 years. According to the report, the microscopic particles from asteroids and comets add up to around 40,000 tonnes of dust every year to our planet. However, this is not a problem for us. But these debris can do damage to spacecraft as it did to the James Webb Space Telescope, which is now permanently damaged.

Natural space debris is uncontrolled, unpredictable and spread evenly across the globe. However, the uncontrolled arrival of artificial space debris, such as spent rocket stages, has significant risk of parts re-entering in the coming decade.

Internationally, there is no clear and widely agreed casualty risk threshold. Till date, no debris from satellites and rockets caused harm on the Earth's surface