The solid inner core at the center of the Earth, surrounded by the outer core, mantle and crust. Here’s why: While it is well known that a material must be at or below its freezing temperature to be ...

Some parts of the U.S. see well over 100 inches (2.5 meters) of snow per year. Edoardo Frola/Moment Open via Getty Images The thought of snow can conjure up images of powdery slopes, days out of ...

Our species likes it cold. Homo sapiens evolved in — and still inhabits — one of Earth’s rare and fragile ice ages, periods distinguished not by an abundance of saber-toothed cats and woolly mammoths ...