Scientists estimate that up to 80% of the planet’s life is found under the surface of the ocean.
Amid the chilly depths, hydrothermal vents release water heated up to a scalding 750º Fahrenheit (400º Celsius).
Phytoplankton — tiny photosynthetic organisms that live in the sea — alone are responsible for half of the oxygen on Earth.
We may imagine the deep ocean as a silent space, yet scientists who’ve listened in say there’s almost constant noise.