New progress in stem-cell research raises some thorny ethical questions.

While writing her forthcoming book about Polynesia, the author discovered the work of Teuira Henry, a scholar and folklorist who studied ancient Tahiti.

Hypersonic aircraft can fly at least five times the speed of sound. They would make for terrifying weapons -- if they are even possible.

In England in the 1920s and ‘30s, nudism was ideological and utopian. Then the Nazis coopted the concept for their eugenicist Nacktkultur movement.