AAVSO Sudden Ionospheric Disturbance Report December 1987 Observers: A-01 A-09 A-19 A-26 A-49 A-50 A-59 YYMMDD Event Peak (UT) Importance 871210 1409 1- 871210 1532 2 871212 1638 1+ 871226 1759 2 871227 1801 1+ ******************************************* Importance Summary December 1987 1- events: 1 1 events: 0 1+ events: 2 2 events: 2 2+ events: 0 3 events: 0 3+ events: 0 Total events: 5