National Geographic - Coasts

If you've ever been to the beach, you've been on a coast. The coast is the land along a sea. The boundary of a coast, where land meets water, is called the coastline...

Geography - Types of Coastlines

Although every coastline is a unique creation of ocean waves acting on distinctive land masses, we can identify seven important types of coasts...

Smithsonian - Astronaut Kathy Sullivan

In 1984, NASA astronaut Kathy Sullivan made history as the first American woman to walk in space. Now, 36 years later, Sullivan has made history again as the first woman to travel to the deepest part of the ocean floor...

Smithsonian - Marie Tharp

There’s no denying that maps can change the way we think about the world. But what about the way we think about what’s underneath? That was the case in 1953, when a young geologist named Marie Tharp made a map that vindicated the controversial theory of plate tectonics...

NOAA - Ocean Coasts & Floors

Beneath the smooth ocean surface extends an underwater landscape as complex as anything you might find on land. While the ocean has an average depth of 2.3 miles, the shape and depth of the seafloor is complex. Some features, like canyons and seamounts, might look familiar, while others, such as hydrothermal vents and methane seeps, are unique to the deep...