Earth’s a medium-size rock with some water on top, enveloped by gases that keep everything that lives here alive. Just at the edge of that envelope begins a thin but dense layer of human-built, high-tech stuff.

People started putting gear up there in 1957, and now it’s a real habit. Telescopes look up and out at the wild universe. Humans live in an orbiting metal bubble. In the last five years, the number of active satellites in space has increased from barely 3,000 to about 14,000—and climbing. The biggest use case: “megaconstellations” like Elon Musk’s Starlink internet service, which by itself has nearly 10,000 satellites in orbit.

And then there’s the garbage: 50,000 bits of debris larger than a baseball now orbit Earth, along with a million more objects bigger than a coin. If you enjoy things like weather forecasts and digital communication, hope they don’t start crashing into each other. Here’s a closer look at Earth’s ever-thickening shell of human-made matter—the anthroposphere.