From the deep ocean floor to vast underground caverns beneath our feet, these places challenge our understanding of the world.

What's at the bottom of the Mariana Trench, and how do we know? How deep does the ocean go? We'll answer these questions and more in this deep dive into the world's oceans. Come on in: The water's ...

I recently participated in a three-week-long, National Science Foundation-funded research cruise to the Mariana Trench. Our target was an east-to-west transect starting near Guam, over the Challenger ...