This story appears in the November 2012 issue of National Geographic magazine. I got my first lesson in the physics of sand dunes in 1998 on an expedition into the Sahara. In order to take aerial ...

The erosion of sand around the ship made it visible to humans ... Researchers believe the vessel could have been a part of a merchant fleet sailing in the Caspian Sea. Experts also located ...

then built a “protective wall” with “thousands” of sand bags to keep the water from filling the ship, the study said. Photos show the process. Eventually, the team uncovered the full ship. It measured ...