Solar Flare WatchHome › Flare history › 1991
M7.8 solar flare on 1991-12-28
ClassM7.8NOAA report
Peak21:121991-12-28 UTC
Duration169 min
Peak flux7.8e-05W/m²
| Comparison | Value |
|---|---|
| Rank in year | 67 / 3297 |
| Other M/X flares that day | 2 |
| M/X flares that month | 94 |
| Solar cycle | Cycle 22 |
| Position on disk | S16W47 |
| Active region | AR 6982 (26 flares) |
Compared with the strongest flares of 1991
X12.0
X12.0
X12.0
X12.0
X12.0
X10.0
X10.0
X9.4
X7.1
X6.1
X5.5
X5.3
Other M/X flares that day
| Date | Begin | Peak | Min | Class | Location | Region |
|---|---|---|---|---|---|---|
| 12:23 | 12:30 | 11 | M3.3 | – | 6991 | |
| 21:48 | 23:04 | 216 | M2.7 | S17W46 | 6982 |
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.
← X1.4 1991-12-24M5.8 1992-01-01 →
About this page
A M7.8 flare that began 1991-12-28 21:08 UTC; No. 67 of 3,297 C-class-or-larger flares in 1991.