Magnetometer
A Magnetometer is a scientific instrument used to measure magnetic fields.Earth's magnetism varies from place to place and differences in the Earth's magnetic field (the magnetosphere) can be caused by a couple things.
- The differing nature of rocks
- The interaction between charged particles from the sun and the magnetsophere.
Magnetometers are very sensitive, and can give an indication of possible auroral activity before one can even see the light from the aurora.