Nonlinear phenomena are phenomena, which, in contrast to a linear system, cannot be explained by a mathematical relationship of proportionality (that is, a linear relationship between two variables).

For centuries, residents in central Japan have chronicled a mysterious natural phenomenon in winter. They see its disappearance as a bad omen. By Martin Fackler and Hisako Ueno Reporting from Suwa ...

On March 29, the Moon is going to enter perigee – the point in its elliptical orbit that brings it closest to Earth. This is known as a supermoon, famous for appearing in the sky as a ...