The late Carl Sagan delivers this moving monologue about our place in the universe.
A look at how the Sphinx of Ramses II was moved at Philadelphia's Penn Museum.
A look at science's goal of eliminating genetic diseases using gene-editing techniques.
This intriguing experiment reveals just what happens when you pour lava on to ice.
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A look at some creepy tales of ghosts and hauntings from the retired ocean liner.