Sixty-six years ago, there was one human-built object in Earth’s orbit. It was Sputnik, the world’s first satellite, launched in October 1957. Try to guess how many human-made objects are circling the planet now. Ready?
Your answer is wrong, unless you guessed 100 trillion. That’s a jaw-dropping number. It was provided by an international team of researchers writing in the journal Science. For years, this junk has formed an ever-growing mass near Earth. It’s a danger to spacecraft. The researchers are calling for a global treaty to limit the number of satellites and the amount of rubbish in space.
“There is no international treaty that seeks to minimize orbital debris,” the scientists write. They say that must change—and fast. “We need collective cooperation, informed by science, to develop a timely, legally binding treaty to protect Earth’s orbit.”
There are 9,000 active satellites in orbit, the scientists report. That could grow to more than 60,000 by 2030. The rest of that 100 trillion figure includes everything from used-up booster rockets and stray bolts to metal flecks and paint chips.
Don’t think a paint chip is harmless. Traveling at 28,000 kilometres per hour, it can strike a spacecraft hard. The International Space Station is dotted with dents and holes. Astronauts often take shelter in an attached spacecraft to wait out a passing swarm of space debris. That way, if the station is severely damaged, they can bail out in a hurry.
All of this debris will eventually fall to Earth and burn up in the atmosphere. But we’re replacing the junk more quickly than it’s falling.