When an electric current passes through a metal wire, a magnetic field forms around that wire (see diagram at right). Likewise, a wire passing through a magnetic field creates an electric current ...

Would a dramatic change in the Earth's magnetic field affect creatures that rely on it during migration? Late on a January night in 1993 I found myself on a beach on the Pacific coast of Costa ...

A magnetic field is invisible, but it can be detected using a magnetic compass. A compass contains a small bar magnet on a pivot so that it can rotate. The compass needle points in the direction ...