On July 17, 2023, there were six active sunspot regions visible on the Earth-facing side of the Sun, including notable regions AR3363, AR3372, and AR3373.1 In visible light, these sunspots appear as dark spots against the bright solar surface. While the visible light image highlights sunspot regions, significant solar activity occurred over the previous 24 hours:
- AR3363, near the Sun’s western limb, produced an M4.0-class flare at 17:36 UT, causing an R1 (minor) radio blackout over the sunlit side of Earth.1
- A total of 20 C-class flares were also recorded, with AR3373 contributing the most activity despite its relatively simple structure.1
- An unnumbered region on the southeast limb of the Sun showed signs of potential future activity.1
Although the visible image does not directly reveal coronal mass ejections (CMEs) or filament eruptions, these events occurred alongside visible sunspot activity.
Photo of the Sun captured on 17 July 2023,2 showing six active regions (sunspots) visible on its Earth-facing side (AR3363 and from AR3371 to AR3375).1
Want to learn more? Check out here for a detailed report on sun activity.
Sun activity for July 17, 2023: CME or CMEs arrive, sun action continues. Earthsky. ↩ ↩2 ↩3 ↩4 ↩5
Sun 2023-07-17. Flickr. ↩