Fig. 2
Magnetometer stations and spacecraft footpoint locations (Kp = 3) in the vicinity of AMPERE FAC (blue is downward, red upward, maximum density approximately 1 μ A/m 2) of the substorm current wedge at 4:39 UT February 24, 2010. THEMIS footpoints are for 4:27 to 4:39 UT, during which the footpoints move westward, and THEMIS A is in orangeand THEMIS D in red. GOES 12 footpoint for the hour 4–5 UT is shown in as a white circle. Geomagnetic latitudes 60° (bottom) and 70° (top) are shown as heavy black lines labeled near 0° geomagnetic longitude, which is near −75° geodetic longitude as labeled at the bottom and, in turn, is near magnetic midnight at this time. Locations of magnetometers of NRCan are shown by red triangles, CARISMA by inverted yellow triangles, MACCS by a yellow triangle, and Polaris by an orange triangle, THEMIS by a red inverted triangle, and DTU by a brown inverted triangle. Stations Rankin Inlet, Gillam, Sanikiluaq, and Kuujuaq have THEMIS all-sky imagers. The town of Fort Churchill hosts both the CARISMA magnetometer designated FCHU and the NRCan observatory FCC