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X1.9 solar flare on 2025-12-01
ClassX1.9GOES-18 science data
Peak02:492025-12-01 UTC
Duration38 min
Peak flux1.9e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (since Jun 2017) | 39 / 108 |
| Rank in year | 5 / 3004 |
| Other M/X flares that day | 0 |
| M/X flares that month | 34 |
| Solar cycle | Cycle 25 |
Compared with the strongest flares of 2025
X5.1
X4.0
X2.4
X1.9
X1.9
X1.8
X1.8
X1.7
X1.7
X1.2
X1.2
X1.2
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.
← M5.9 2025-11-28M6.0 2025-12-04 →
About this page
A X1.9 flare that began 2025-12-01 02:27 UTC; No. 5 of 3,004 C-class-or-larger flares in 2025.