Magnetic field observed at spacecraft located in the inner magnetosphere. For the GOES spacecraft, magnetic field is given in the direction parallel (H_p), earthward (H_e) and normal (H_n) to magnetic field lines. For the THEMIS spacecraft, magnetic field is given in the X (B_x), Y (B_y) and Z (B_z) directions in GSM coordinates. Parameters are plotted for 1800–1830 UT 19 November 2007. Dashed lines indicate the SI onset times.