During an opportune alignment that occurred during the recovery phase of a large geomagnetic storm, observations with different instruments from several different points were carried out.

A low frequency type of ULF wave, comparable to a beep every 10 minutes, was recorded continuously for many hours by the CARISMA magnetometer chain in Northern Canada. The waves were picked up by more than a dozen scientific satellites including the four ESA Cluster satellites, NASA’s Polar spacecraft and four of the Geostationary Operational Environmental Satellites (GOES).

Credits: University of Alberta (A. Kale )

Ionospheric footprints in pink for ESA’s Cluster, in purple for NASA’s Polar and green for the GOES satellites. The projection looks down on the northern hemisphere. The field-of-view of radars of the SuperDARN network is underlined in black. In red, the positions of the CARISMA (University of Alberta, Canada) and SAMNET (Lancaster University, UK) magnetometers chains have been indicated.

12 MLT indicates noon, Magnetic Local Time, or the direction of the Sun, the source of solar wind. 24 MLT indicates the direction opposite to noon, Magnetic Local Time, least affected by solar wind.

Credits: University of Alberta (I. Rae)