Solar Flare WatchHome › Flare history › 1981
X1.5 solar flare on 1981-07-27
ClassX1.5NOAA report
Peak17:241981-07-27 UTC
Duration84 min
Peak flux1.5e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 259 / 491 |
| Rank in year | 22 / 4022 |
| Other M/X flares that day | 4 |
| M/X flares that month | 74 |
| Solar cycle | Cycle 21 |
| Position on disk | S13E11 |
| Active region | AR 3234 (84 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 |
|---|---|---|---|---|---|---|
| 01:04 | 01:15 | 47 | M2.1 | S11E05 | 3234 | |
| 04:09 | 04:14 | 28 | M1.4 | S07W42 | 3221 | |
| 06:14 | 06:32 | 36 | M9.3 | S13E11 | 3234 | |
| 11:35 | 11:37 | 32 | M2.7 | S17E20 | 3234 |
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.
← M9.3 1981-07-27M5.1 1981-07-30 →
About this page
A X1.5 flare that began 1981-07-27 17:24 UTC; No. 22 of 4,022 C-class-or-larger flares in 1981.