The flurry of recognition seems appropriate for a region that covers 70 percent of the Earth's surface and provides about half the air we breathe, courtesy of the microscopic, oxygen-producing phytoplankton floating in it.

Yet much about the planet's oceans remains a mystery. As of the year 2000, the National Oceanic and Atmospheric Administration (NOAA) estimated that as much as 95 percent of the world's oceans and 99 percent of the ocean floor are unexplored.

Exploring these regions deep below the ocean's surface is difficult, time-consuming, and expensive. Which hasn't stopped people from trying — and making incredible discoveries along the way.