In some places, sand dunes protect shorelines from the onslaught of ocean waves. In other places, the dunes themselves are on the move, and threaten human structures. Host Flora Lichtman talks with ...
Filmmakers trekked through Death Valley National Park to capture these images of the Geminid meteor shower on December 13. Kasia Cieplak-Mayr von Baldegg is the former executive producer and general ...
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