The USGS Geomagnetism Program currently operates 14 magnetic observatories.
Magnetometer data are collected at these facilities, and the data are then transmitted to
Program headquarters in Golden Colorado. The geographic distribution of the Program’s
observatories, shown below, has been determined by the need to monitor and study
the geomagnetic field on a global scale, primarily for purposes of space-weather
diagnosis and main field modelling and mapping, as well as the practical issues
of availability of land, communication and operational logistics, and the relative
locations of observatories operated by other foreign-national programs.