Oceanography Trivia

Oceans cover most of the planet, yet we've charted more of the moon's surface in detail than we have the sea floor. This quiz dives into the currents, creatures, and expeditions that shaped our understanding of the deep.

Charting the Deep

Modern oceanography traces back to the HMS Challenger expedition of 1872–76, a voyage that circled the globe collecting samples and soundings and effectively founded the science. It took nearly another century before humans actually reached the ocean's deepest point: in 1960, Don Walsh and Jacques Piccard rode the bathyscaphe Trieste down to the Challenger Deep in the Mariana Trench.

The Ocean in Layers

Sunlight only penetrates so far, and the ocean's layers are defined by how much of it gets through.

• Photic zone — sunlit surface layer, where photosynthesis happens
• Twilight zone — dim, faint light, roughly 200 to 1,000 meters down
• Midnight zone — permanent darkness below about 1,000 meters

Currents, Salt, and Strange Life

Ocean water isn't static — thermohaline circulation, the slow global "conveyor belt" driven by heat and salinity differences, redistributes warmth around the planet over centuries. And in 1977, researchers near the Galápagos Islands found something nobody expected at the bottom of that darkness: hydrothermal vents crowded with life that runs entirely on chemical energy rather than sunlight.