When hundreds of eerily perfect circles were discovered on the bottom of the Mediterranean Sea, theories abounded about what they could mean. Four years of underwater research revealed a lost world.
What are the top facts about the ocean? While much is known about the ocean, a large part of it remains unknown. Here are fun facts about it for people of all ages.
Even so, little more than 25 percent of the ocean floor has been mapped in detail: We know more about the surface of Mars. This prompted astrophysicist and National Geographic Explorer ...
Since National Geographic began making maps in 1915 ... ocean waters to the north Extending from the surface to the ocean floor, the ACC transports more water than any other ocean current.