17 October 2019 - Mission Day: 8721 - DOY: 290

MDI Sunspot size winner -- Active region 10486 became the largest sunspot seen by SOHO, It unleashed a spectacular show on 28 October 2003. An X 17.2 flare, the second largest flare observed by SOHO and the third largest ever recorded, blasted off a strong high energy proton event and a fast-moving Coronal Mass Ejection. The spot occupied an area equal to about 15 Earths, a size not seen since 1989. It later fired off the largest X-ray flare recorded, on 4 November 2003.



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