Magnetometer is a scientific instrument used to measure the strength and/or direction of the magnetic field in the vicinity of the instrument. Magnetometers are used in geophysical surveys to find deposits of iron because they can measure the magnetic pull of iron. It is also used to detect archaeological sites, shipwrecks and other buried or submerged objects. It can also be used by satellites like GOES to measure both the magnitude and direction of the earth's magnetic field. Magnetometers can be divided into two basic types such as scalar magnetometers and vector magnetometers. A magnetograph is a special magnetometer that continuously records data.