Solar Flare WatchHome › Flare history › 1990
X5.5 solar flare on 1990-05-21
ClassX5.5NOAA report
Peak22:171990-05-21 UTC
Duration87 min
Peak flux5.5e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 48 / 491 |
| Rank in year | 2 / 2551 |
| Other M/X flares that day | 2 |
| M/X flares that month | 36 |
| Solar cycle | Cycle 22 |
| Position on disk | N35W36 |
| Active region | AR 6063 (23 flares) |
Compared with the strongest flares of 1990
X9.3
X5.5
X3.6
X3.4
X3.0
X2.4
X2.2
X1.9
X1.8
X1.7
X1.5
X1.4
Other M/X flares that day
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.
← X1.7 1990-05-15M8.7 1990-05-23 →
About this page
A X5.5 flare that began 1990-05-21 22:12 UTC; No. 2 of 2,551 C-class-or-larger flares in 1990.