Solar Flare WatchHome › Flare history › 1999
X1.4 solar flare on 1999-08-02
ClassX1.4NOAA report
Peak21:251999-08-02 UTC
Duration20 min
Peak flux1.4e-04W/m²
| Comparison | Value |
|---|---|
| Rank among X flares (1975 – Jun 2017) | 293 / 491 |
| Rank in year | 2 / 2025 |
| Other M/X flares that day | 1 |
| M/X flares that month | 25 |
| Solar cycle | Cycle 23 |
| Position on disk | S18W46 |
| Active region | AR 8647 (10 flares) |
Compared with the strongest flares of 1999
X1.8
X1.4
X1.4
X1.1
M9.8
M8.0
M7.6
M7.4
M6.6
M6.2
M6.0
M6.0
Other M/X flares that day
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 00:23 | 00:27 | 7 | M1.8 | – | – |
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 1999-07-29M6.0 1999-08-04 →
About this page
A X1.4 flare that began 1999-08-02 21:18 UTC; No. 2 of 2,025 C-class-or-larger flares in 1999.