AAVSO Sudden Ionospheric Disturbance Report January 1990 Observers: A-01 A-19 A-46 A-50 A-52 A-59 A-61 A-62 A-63 A-64 A-65 A-66 A-67 YYMMDD Event Peak (UT) Importance 900101 0820 2 900101 1015 2+ 900101 1515 1- 900101 2128 2 900102 1500 1- 900102 1914 2 900103 0626 2 900104 0355 2+ 900104 0525 2 900104 1615 2 900105 1652 2 900105 2013 2+ 900108 1718 1+ 900109 0701 1+ 900109 0734 2 900109 1456 2+ 900109 2046 2 900110 0240 2+ 900110 2021 2 900110 2110 2 900112 0744 1 900112 0752 2+ 900113 0620 2+ 900114 1006 2+ 900114 1608 1 900115 0650 2+ 900115 1610 2 900116 0752 3+ 900117 0540 2+ 900117 0720 1+ 900117 0857 1 900118 0420 2+ 900118 1545 1 900119 0425 2 900119 0844 1 900119 0915 2 900119 1545 3 900120 1329 2+ 900120 1713 1+ 900120 1714 2 900120 2118 2 900121 0436 2+ 900121 1615 3 900121 1815 2+ 900121 1951 2 900123 0508 2 900123 1700 1- 900123 1830 1+ 900123 1917 1+ 900124 0640 1 900124 0705 1 900124 1720 1- 900124 2015 2+ 900125 0727 1 900126 0515 2+ 900126 1618 1- 900127 0856 2 900128 1618 1 900131 1025 2 ******************************************* Importance Summary January 1990 1- events: 5 1 events: 9 1+ events: 6 2 events: 20 2+ events: 16 3 events: 2 3+ events: 1 Total events: 59