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X1.7 solar flare on 1981-07-17
ClassX1.7NOAA report
Peak08:091981-07-17 UTC
Duration37 min
Peak flux1.7e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 231 / 491 |
| Rank in year | 20 / 4022 |
| Other M/X flares that day | 4 |
| M/X flares that month | 74 |
| Solar cycle | Cycle 21 |
| Active region | AR 3221 (32 flares) |
Compared with the strongest flares of 1981
X5.9
X5.5
X4.0
X3.6
X3.5
X3.1
X3.0
X2.7
X2.6
X2.5
X2.4
X2.3
Other M/X flares that day
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 01:48 | 01:53 | 72 | M4.1 | S09W30 | 3203 | |
| 11:23 | 11:27 | 10 | M1.2 | – | – | |
| 12:09 | 12:30 | 77 | M3.7 | S08E37 | 3203 | |
| 17:03 | 17:03 | 59 | M1.6 | S08W41 | 3203 |
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.
← M5.1 1981-07-15M9.1 1981-07-19 →
About this page
A X1.7 flare that began 1981-07-17 07:53 UTC; No. 20 of 4,022 C-class-or-larger flares in 1981.