These ancient structures still stand - but the people who built them remain a mystery that history can’t fully explain.

Scientists can peer into cells to get a limited view of their activity using microscopes and other tools. However, cells and ...

For centuries, the Ring Nebula has captivated astronomers with its stunning, glowing appearance, but a recent discovery has ...

During the season eight premiere episode of "The UnXplained" host William Shatner takes viewers all over the world to examine ancient structures.