... Credit Copyright: Kwon, O Chul ( TWAN ) Explanation: Intense auroral activity flooded the night with shimmering colors on February 24, captured here from a lodge near the city of Yellowknife in northern Canada. ... Measurements by NASA's fleet of THEMIS spacecraft indicate that these explosions of auroral activity are driven by sudden releases of energy in the Earth's magnetosphere called magnetic reconnection events. ... Publications with keywords: aurora - night sky - Themis - magnetic field . ...