A plastic bag, a dirty pizza box, plastic utensils, paper napkins, and a soda can—a single takeout meal can feel like a game of recycling trivia. Which items can be recycled? What kinds of plastic go ...

Mars has captivated humans since we first set eyes on it as a star-like object in the night sky. Early on, its reddish hue set the planet apart from its shimmering siblings, each compelling in its own ...