10 per cent chance falling rockets will hit someone in next decade

The author is Jonathan O'Callaghan.

If action is not taken, pieces of rocket falling back into our atmosphere may cause casualties.

The number of rockets successfully launched in a single year is the highest it has ever been. After a satellite is boosted into its desired position, part of the rocket is thrown away. More than 1000 rocket bodies are estimated to have reentered the atmosphere in the past 30 years.

More than two-thirds of our planet's surface is covered by the ocean, but some debris ends up on the ground. A 12-metre-long pipe is believed to have come from a Chinese rocket in May 2020. There was a piece of debris that came from a Chinese rocket that landed in India. The Wreckage of a Chinese Long March rocket landed in China in December of last year.

Michael Byers is a professor at the University of British Columbia in Canada. There is a 10 per cent chance of one or more casualties being caused by falling debris over the next decade, and the risk is disproportionately higher in low-income nations near the equator.

Byers wants rocket companies to be told to keep leftover fuel for safe re-entries. Modern rockets can avoid re-entries, instead of playing Russian roulette. The next piece won't be in central Mumbai.

Jonathan McDowell at the Harvard-Smithsonian Center for Astrophysics says that space debris is a big problem. There is a collision risk when there are stages left. Fuel left on the stage can cause it to explode. De-orbiting your rocket is the only way to make sure it won't explode.

If debris from a rocket causes damage or casualties on Earth, legal action can be taken under the United Nations's liability convention. In 1981 Canada was awarded CAN$3 million (US$2.3 million) from the Soviet Union after a soviet satellite crashed in the country, but the convention could be used again.

There will be another serious incident. There is a high chance of hurting someone or damaging property.

The lower part of a rocket's first stage can be landed on the ground. The second stage is left to drift in space, rather than being brought back through Earth's atmosphere into uninhabited regions of the ocean, because the rockets carry the precise amount of fuel to do their job.

The China National Space Administration didn't reply to a request for comment.

The goal is to phase out re-entries. Older rocket designs may need to be modified.

Nature Astronomy was published in the journal.

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