Humanity left an irreversible imprint upon Earth's rocks. Here's how.

Studying everything from atomic bomb fallout to pesticide residues, scientists are close to defining the start of the Anthropocene—the geologic age of human impact.

Read This Next

How your favorite plant-based milk impacts the planet
Christianity struggled to grow—until this skeptic became a believer
Winter is coming. These trips help you embrace it—or escape it.

Go Further

Subscriber Exclusive Content

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet

Why are people so dang obsessed with Mars?

How viruses shape our world

The era of greyhound racing in the U.S. is coming to an end

See how people have imagined life on Mars through history

See how NASA’s new Mars rover will explore the red planet