Schematic diagram showing Cluster, Swarm and regions of the magnetosphere
![](https://cdn.sci.esa.int/documents/34817/35562/1567215959840-FAC_Cluster_Swarm_tec_625w.jpg)
Date: 30 June 2015
Satellite: Cluster
Copyright: ESA
This schematic figure illustrates the location of the four Cluster and three Swarm satellites during a study carried out in April 2014.
During this study, the seven spacecraft joined forces to simultaneously measure the properties of Earth's magnetic field at two different altitudes.
A number of striking similarities in the behaviour and structure of the field-aligned currents detected at each altitude were found, despite their vastly different locations. Field-aligned currents (FACs) - indicated in yellow - flow along Earth's magnetic field lines, transferring energy from region to region.
Last Update: 1 September 2019