Dynamic and intense polar auroras were observed over Eureka, Canada (88.9 ¿N magnetic) through January 10 and 11 following the solar coronal mass ejection (CME) of January 6, 1997. A dusk sector arc appeared by 0200 UT on January 10 following the arrival of the magnetic shock at 0110 UT; aurora filled the Eureka field of view between 0225 and 0300 UT. Spectral measurements with allsky cameras, meridian scanning photometers and a CCD spectrograph showed this aurora to be excited by electrons of E0≈3 keV. After an interval of F-layer patches, faint F-layer arcs (E0≈300 eV) reappeared by 1900 UT and continued until 0700 UT on January 11, intensifying between 0200 and 0700 UT. The initial auroral display was remarkable in its spectral characteristics, while the prolonged F-layer aurora which followed was similar to the aurora observed during the October 1995 magnetic cloud event. ¿ 1998 American Geophysical Union