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X12.0 solar flare on 1991-06-04

ClassX12.0NOAA report

Peak–1991-06-04 UTC

Duration233 min

Peak flux1.2e-03W/m²

Comparison	Value
Rank among X flares (1975 – Jun 2017)	13 / 491
Rank in year	2 / 3297
Other M/X flares that day	2
M/X flares that month	72
Solar cycle	Cycle 22
Position on disk	N30E70
Active region	AR 6659 (72 flares)

Compared with the strongest flares of 1991

X12.0 06-01X12.0

X12.0 06-04X12.0

X12.0 06-06X12.0

X12.0 06-11X12.0

X12.0 06-15X12.0

X10.0 01-25X10.0

X10.0 06-09X10.0

X9.4 03-22X9.4

X7.1 03-04X7.1

X6.1 10-27X6.1

X5.5 03-07X5.5

X5.3 03-25X5.3

Other M/X flares that day

Date	Begin	Peak	Min	Class	Location	Region
	20:10	20:14	9	M1.0	–	6659
	23:48	00:04	26	M1.4	–	6652

All times UTC. Until June 2017 classes are NOAA's reports of the time (GOES-15 and earlier included a 0.7 scaling factor); later classes come from calibrated GOES-16/18 data, so the same flare reads about 1.4× larger. Do not compare the two periods directly.

← M5.2 1991-06-02 X12.0 1991-06-06 →

About this page

A X12.0 flare that began 1991-06-04 03:37 UTC; No. 2 of 3,297 C-class-or-larger flares in 1991.