AAVSO Sudden Ionospheric Disturbance Report December 1997 Observers: A-05 A-09 A-50 A-52 A-62 A-63 A-72 A-80 A-81 A-82 A-84 A-87 A-89 YYMMDD Event Peak (UT) Importance 971201 1324 1- 971203 1348 2+ 971206 0834 1 971209 0935 1- 971211 1253 1- 971211 1302 1- 971212 1048 1- 971212 1147 1- 971212 1218 1- 971221 0349 2 971221 1646 2 971222 1519 2 971226 0557 1- 971227 1638 1+ 971231 1827 1 971231 2025 2+ ******************************************* Importance Summary December 1997 1- events: 8 1 events: 2 1+ events: 1 2 events: 3 2+ events: 2 3 events: 0 3+ events: 0 Total events: 16