Not since the 1960s space race has the world been as enthusiastic about space travel. Privatized efforts from the likes of Blue Origin and SpaceX are creating new opportunities for civilians to leave the planet.
There is a small but significant chance, however, those of us left behind will get creamed by space debris, making for some lively obituaries.
A recent paper by scientists in British Columbia and published in the journal Nature Astronomy attempted to crunch some numbers and arrive at what might be a plausible chance of space junk falling back to Earth and killing someone in the next 10 years. Such risks are nominally due to spent rocket stages, the clutter left behind by rocket and satellite launches.
Using data from past projects, population densities, and trajectories of rocket parts, researchers determined there’s a reasonable chance that spent rocket parts will re-enter the Earth’s atmosphere in the next 10 years. There's also a 10 percent chance one or more of those pieces will cause a lethal collision with one or more unsuspecting victims.
This event is more likely to happen in southern latitudes, meaning spots in Indonesia and Bangladesh may be at higher risk than, say, Arizona.
This is a shockingly plausible scenario, given rocket debris that’s already made its way back. In 2016, two refrigerator-sized fuel tanks from a SpaceX rocket landed in Indonesia. No one was in the path, but if they were, the outcome would have been messy.
There is no standardized set of guidelines for how to mitigate such debris, though that could change as more and more launches take place. One idea is to have spent parts carry fuel to control their re-entry to non-populated areas or be comprised of materials that can burn up upon re-entry.
The study’s authors assert that space companies may resist such efforts owing to associated costs, so government mandates may be warranted.
No one has yet died from manufactured space debris falling on them, though meteorites can occasionally cause havoc. The earliest known meteorite fatality involved a man in what’s now Iraq in 1888. One struck a cow in 1972, killing it; another shot through the roof of a woman's house in Alabama in 1954, leaving a large welt on her thigh when it landed next to her.
[h/t Science Alert]