Dark matter seems invisible, but it makes up most matter, and we have evidence that it gives the cosmos its shape. Now ...

Snow is made of tiny ice crystals that can transform into a variety of intricate symmetrical patterns forming a beautiful ...

Meteorologists warn that a stretched polar vortex could bring severe winter weather to much of the United States.

As the U.S. prepares to take on another bout of cold weather, the term "polar vortex" is getting thrown around. But what is ...