Sixty-six years ago, there was a single human-built object in earth orbit: Sputnik, the world’s first satellite. Today, there are 100 trillion objects circling the planet. That’s the jaw-dropping number cited by international researchers in an open letter published March 9 in Science, calling for a global treaty to curb the ever-growing debris belt in low-earth orbit.
DANGEROUS DEBRIS The junk belt includes 9,000 active satellites. Then there are the spent boosters, stray bolts, and floating paint chips that go along with launching all of that hardware. Orbiting the earth at 28,200 km/h (17,500 m.p.h.), even the smallest pieces of rubbish can strike an object like a bullet. Astronauts aboard the International Space Station must routinely shelter in the attached Soyuz or SpaceX spacecraft to wait out a passing…