Sunspot region AR 4521

Sunspot AR 4521 is a moderate-sized, magnetically simple active region visible on the Sun. It contains 1 spots and covers 80 millionths of the solar hemisphere. This region has produced 2 C-class flares. Current flare probabilities are C 10%, M 1% and X 1%. Its heliographic latitude is N9°, Earth-facing longitude 39° and Carrington longitude 263°.

Sunspot location on the solar map

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Selected map type: AIA 171 Å

Sunspot properties

Region number	4521
First observed	30 August 2026 at 22:19
Sunspot type	Hsx
Magnetic class	A
Area	80 MSH
Spot count	1
Heliographic extent	2 degrees
Latitude	9°
Longitude	39°
Carrington longitude	263
Status	f

Flare activity

Flare class	Begin time (UTC)	Peak time (UTC)	End time (UTC)	Location	Duration
C1.0	2026-08-30 18:31	2026-08-30 18:33	2026-08-30 18:35	N12E80	2 minutes
C3.0	2026-08-29 16:10	2026-08-29 16:20	2026-08-29 16:25	N12E90	10 minutes

Sunspot evolution

These graphs show how the region’s area and visible spot count changed over time.

Area

Area is measured in millionths of the solar hemisphere (MSH); growth can indicate increasing magnetic complexity.

Spot count

The spot count records the visible spots in the region at each observation.

Detailed history

Date	Area (MSH)	Spot count	Classification	flares	Location
2026-09-02	80	1	Hsx	-	N09E39
2026-09-01	50	2	Hsx	-	N09E53
2026-08-31	60	1	Hsx	C1.0, 18:31-18:35	N09E67

Acknowledgments

We thank the teams behind the Solar Dynamics Observatory (SDO), including the HMI, AIA and EVE teams, for continuous solar monitoring.

We also thank National Aeronautics and Space Administration (NASA), Goddard Space Flight Center (GSFC), National Oceanic and Atmospheric Administration (NOAA) for supporting solar science and public data access.

Additional event data are provided by NASA’s DONKI (Database of Notifications, Knowledge, Information), with records of flares, CMEs and geomagnetic storms.

Observation Settings