Sun · flares

A Sun that bursts

Flares are sudden releases of magnetic energy above active regions. The flashes in this view recall the classes of the strongest flares in the GOES catalogue (X, M); their positions are illustrative.

Latest catalogued flare

B4.3

2026-10-25 03:33 UTC

Strongest in the catalogue

X28

2003-11-04

X-class flares

558

1975 → 2026

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Illustrative rendering: procedural prominence loops and flashes; classes from the GOES catalogue below.

Catalogued flares

94,036

1975 → 2026-10-25

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

X-class flares

558

7954 M-class

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Latest catalogued flare

B4.3

2026-10-25 03:33 UTC · AR 14560

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Strongest in the catalogue

X28

2003-11-04 18:29 UTC · S19W83

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

X- and M-class flares per year GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26 GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Show the data as a table

Number of flares per calendar year in the GOES catalogue (NOAA). The current year is provisional; 2020 is marked “instrument change”: since December 2019 the flux is no longer reduced by the 0.7 factor, which raises classes by about 40%.

C-class flares per year GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Show the data as a table

Detection of C-class flares depends on the background level, hence on the cycle phase and the instrument; these counts are less homogeneous than those of M and X classes.

Ten strongest flares (peak flux derived from the class)

#	Class	Start (UTC)	Peak	Peak flux (W/m²)	Position	Active region
1	X28	2003-11-04 18:29	18:50	3E-3	S19W83	10486
2	X20	1989-08-15 23:08	23:17	2E-3	S18W84	5629
3	X20	2001-04-02 19:32	19:51	2E-3	—	—
4	X17	2003-10-28 08:51	10:10	2E-3	—	10486
5	X17	2005-09-07 15:17	15:40	2E-3	S11E77	10808
6	X15	1989-03-06 12:54	13:10	2E-3	N35E69	5395
7	X14	2001-04-15 11:19	11:50	1E-3	S20W85	9415
8	X13	1984-04-24 21:56	22:01	1E-3	S12E43	4474
9	X13	1989-10-19 11:29	11:55	1E-3	S27E10	5747
10	X12	1982-06-06 14:30	14:54	1E-3	S09E25	3763

The peak flux (0.1–0.8 nm, W/m²) is derived from the published class, e.g. X28 = 28 × 10⁻⁴ W/m²; the GOES detectors saturated above X17 before 2003, so the 4 November 2003 flare is an estimate.

Filterable catalogue GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC) · U.S. Government work, public domain (NOAA/NASA) · 10/25/26

Year

Minimum class

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Start (UTC)	Peak	End	Duration	Class	Peak flux (W/m²)	Position	Active region
2005-01-15 03:26	03:31	03:36	10 min	M8.4	8E-5	N14E06	10720
2005-01-15 03:09	03:16	03:22	13 min	M1.3	1E-5	N11E08	10720
2005-01-14 23:22	23:43	00:02	40 min	X1.2	1E-4	N14E08	10720
2005-01-14 20:08	20:26	20:39	31 min	M1.9	2E-5	N14E10	10720
2005-01-14 16:53	16:57	17:03	10 min	M1.5	2E-5	N14E12	10720
2005-01-14 15:02	15:06	15:14	12 min	M1	1E-5	S06E02	10718
2005-01-14 12:53	13:11	13:45	52 min	M1.8	2E-5	N14E14	10720
2005-01-09 07:25	07:51	08:09	44 min	M2.4	2E-5	S09E69	10719
2004-12-31 23:01	23:31	23:39	38 min	X1.7	2E-4	N06E34	10715
2004-12-31 13:38	13:45	13:48	10 min	M1.2	1E-5	N04E38	10715
2004-12-30 21:02	21:18	21:28	26 min	M4.2	4E-5	N04E46	10715
2004-12-30 09:34	09:47	09:57	23 min	M2.2	2E-5	N03E53	10715
2004-12-29 18:10	18:20	18:25	15 min	M1.4	1E-5	S12W90	10713
2004-12-29 14:57	15:27	15:38	41 min	M2.3	2E-5	N04E62	10715
2004-12-02 22:44	23:06	23:35	51 min	M1.5	2E-5	N08W02	10708
2004-12-01 06:00	06:20	06:41	41 min	M1.1	1E-5	N09E19	10708
2004-11-10 00:59	01:13	01:20	21 min	X2.5	2E-4	N09W49	10696
2004-11-09 15:59	16:19	16:32	33 min	M8.9	9E-5	N08W51	10696
2004-11-08 14:43	14:49	14:52	9 min	M2.3	2E-5	N08W35	10696
2004-11-07 14:42	15:06	15:15	33 min	X2	2E-4	N09W17	10696
2004-11-06 18:38	18:53	19:03	25 min	M1.4	1E-5	N09W06	10696
2004-11-06 00:40	00:57	01:08	28 min	M3.6	4E-5	—	10696
2004-11-05 23:44	23:57	00:10	26 min	M5.9	6E-5	—	10696
2004-11-05 23:11	23:34	23:42	31 min	M9.3	9E-5	N10E08	10696
2004-11-05 18:10	18:22	18:32	22 min	M1.2	1E-5	N10E06	10696
2004-11-05 10:23	10:30	10:33	10 min	M4	4E-5	N08E15	10696
2004-11-04 21:53	22:09	22:26	33 min	M5.4	5E-5	N08E18	10696
2004-11-04 20:42	21:29	21:53	71 min	M2.5	2E-5	N11E19	10696
2004-11-03 17:03	17:26	17:35	32 min	M1	1E-5	N09E32	10696
2004-11-03 14:35	14:47	14:55	20 min	M5	5E-5	N09E38	10696
2004-11-03 02:23	02:35	02:57	34 min	M1.6	2E-5	N09E45	10696
2004-11-03 00:23	00:33	00:37	14 min	M2.8	3E-5	N12W75	10691
2004-11-01 02:04	02:22	02:26	22 min	M1.1	1E-5	N12W49	10691
2004-10-31 04:23	04:32	04:39	16 min	M2.3	2E-5	N12W36	10691
2004-10-31 01:04	01:26	01:32	28 min	M1.1	1E-5	N12W35	10691
2004-10-30 14:18	14:33	14:37	19 min	M5.9	6E-5	N13W28	10691
2004-10-30 09:38	09:46	09:50	12 min	X1.2	1E-4	N13W25	10691
2004-10-30 07:09	07:28	07:30	21 min	M3.7	4E-5	N14W24	10691
2004-10-30 04:08	04:18	04:22	14 min	M4.2	4E-5	N13W22	10691
2004-10-30 01:23	01:33	01:37	14 min	M3.3	3E-5	N13W20	10691
2004-10-24 18:17	18:28	18:35	18 min	M2.3	2E-5	N10E15	10687
2004-10-22 05:52	06:11	06:16	24 min	M2.1	2E-5	N11E44	10687
2004-10-20 08:43	08:51	08:56	13 min	M2.6	3E-5	N11E68	10687
2004-09-19 14:46	15:12	15:39	53 min	M1.9	2E-5	N03W58	10672
2004-09-14 05:47	07:30	08:00	133 min	M1.5	2E-5	N03E16	10672
2004-09-11 23:36	23:39	23:41	5 min	M3.2	3E-5	S14W61	10667
2004-09-11 22:04	22:56	23:33	89 min	M4.8	5E-5	N03E49	10672
2004-08-31 03:24	03:38	03:47	23 min	M1.4	1E-5	N06W82	10663
2004-08-19 11:29	11:51	12:16	47 min	M2.1	2E-5	S13W90	10656
2004-08-19 04:35	05:01	05:18	43 min	M3	3E-5	S13W90	10656

Method and sources

The catalogue reproduces the NOAA (SWPC/NGDC) GOES event lists compiled yearly by the NASA GSFC Hesperia centre: start, peak and end (UT), class, heliographic position and active region when known. The class encodes the peak flux in the 0.1–0.8 nm band: C = 10⁻⁶ W/m², M = 10⁻⁵, X = 10⁻⁴, times the number (M2.3 = 2.3 × 10⁻⁵ W/m²).

Lines without an X-ray class (optical or sub-threshold events) are not imported. The last two years are re-read on each import; duplicates are rejected by start time and class. Yearly counts are computed from the imported catalogue.

Reading these data

Until December 2019 NOAA applied a 0.7 factor to the XRS-B flux of GOES 8 to 15; since GOES-16 became the primary satellite the raw flux is used. For the same physical flux, a class after 2020 is therefore about 1.4 times higher (Janssens et al., 2025). Counts before and after 2020 are not directly comparable.

SOURCES OF THIS PAGE

GOES X-ray flare lists (NOAA SWPC/NGDC events, yearly compilations by NASA GSFC): NOAA SWPC/NGDC GOES X-ray flare event lists (1975–), yearly compilations by K. Tolbert, NASA GSFC Hesperia. Flare classes as reported by NOAA at the time: until December 2019 the XRS-B flux carried a 0.7 scaling factor (Janssens et al., 2025). · source page ↗
Licence : U.S. Government work, public domain (NOAA/NASA) · retrieved on Oct 25, 2026 · SHA-256 a1d99f7354e3…
Janssens (2025): Janssens, J., et al. (2025). Solar flare rates and probabilities based on the McIntosh classification: impacts of GOES/XRS rescaling and recalibration. Journal of Space Weather and Space Climate. · doi:10.1051/swsc/2025007
Licence : Published literature; cited

Solar flares GOES X-ray flare catalogue since 1975

A Sun that bursts