17 April 2024 - Mission Day: 10365 - DOY: 108
Pick of The Week

Flashpoint! An X-3 flare (July 17, 2002)

On 15 July 2002, a large (X-3) flare and a coronal mass ejection (CME) exploded out from the Sun, the largest flare observed since 28 December 2001. We have seen only four X-class flares this year. The source of the flare and CME was Active Region 30, which scientists were watching carefully as it had the characteristics of sunspots that produce X-class flares. The large sunspot region (many Earths across) can be seen in the MDI video clip and still image up to just hours before the flare.

The trademark flash point of the flare was seen in the ultraviolet EIT 195 Angstrom image at about 20:12 UT. The LASCO C3 instrument shows a fast-moving cloud of particles heading off left of center over the course of a few hours. Thus, it may deliver a glancing blow to Earth. The leading edge of the CME may reach us on July 17 or soon thereafter and may generate some intense auroral activity.

Previous Picks of the Week

SOHO began its Weekly Pick some time after sending a weekly image or video clip to the American Museum of Natural History (Rose Center) in New York City. There, the SOHO Weekly Pick is displayed with some annotations on a large plasma display.

If your institution would also like to receive the same Weekly Pick from us for display (usually in Photoshop or QuickTime format), please send your inquiry to steele.hill@gsfc.nasa.gov.


• European Site • US Site


Feedback & Comments: SOHO Webmaster

Last modification: July 27, 2020

SOHO is a project of international cooperation between