For centuries, people around the world have reported strange glowing spheres during thunderstorms — often floating, crackling ...

At the end of the 1600s, Newton proposed the universal law of gravitation: that every particle attracts every other particle in the universe with a force (F) determined by their masses (M) and the ...

An astronaut on the International Space Station captured mysterious blue spheres in the sky last year. NASA's Earth Observatory shared the photo last year, as well, shortly after it was taken. The ...