Subject: BBSO Solar Activity Warning 19-AUG-1999 23:04:10 UT Date: Thu, 19 Aug 1999 16:14:20 -0700 From: activity@bbso.njit.edu To: sxt_co@isass0.solar.isas.ac.jp The large "S-shaped" filament in NOAA 8668, N20E03, is active and displaced from the neutral line which infers that it is rising. WM >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> >Date: Sun, 22 Aug 1999 12:26:27 +0900 >From: KUROKAWA Hiroki >To: canfield@mithra.physics.montana.edu >Subject: Re: MMOC002 Target > >Dear Canfield san; > > I wonder no large flare of more than M-class occurred during the disappearance >of the southern part of the S-shape filament in NOAA 8668. > By our Halpha observations around 02 UT of 22 Aug. a small EFR was found >to be emerging at the site of the disppeared filament. > > H. Kurokawa >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Observer's report from S. Martin at Helio Research Sun, 22 Aug 1999 10:44:08 We confirm the report by Kurokawa san of the presence of a rapidly growing emerging flux region throughout the day on 21 August. The reverse-S shaped filament was either split into by the emergence of the new flux or the new flux developed close to where the upper and lower parts of the reverse S configuration separated into two filaments. The emerging flux region continues to grow today. Between this EFR and the filament is another new EFR today, 22 August. This second one does not yet have spots and the arch filaments are small at this time and not very conspicuous. The larger EFR has growing sunspots. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Sara F. Martin sara@helioresearch.org Helio Research http://helioresearch.org 5212 Maryland Ave. Phone: 818-957-7507 La Crescenta, CA 91214 FAX: 818-957-7092 <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Tue, 24 Aug 1999 06:40:55 -0700 Hi Sarah, Yesterday our Helio Research observer, Pete Zink, called to my attention that the filament in the target area south of the sunspot is now sinistral! We confirm that this part has been sinistral for at least 2 days, 22 and 23 August, along with a partial southward shift in location of the southern end of the filament. This is quite a surprise as the original filament was dextral. Sara >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> Sara F. Martin sara@helioresearch.org Helio Research http://helioresearch.org 5212 Maryland Ave. Phone: 818-957-7507 La Crescenta, CA 91214 FAX: 818-957-7092 <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<< Wed, 25 Aug 1999 09:54:18 -0700 (PDT) Hi Sarah, I would like to report that the filament in the target area south of the sunspot seems to have largely dissapeared. This observation is based on H-Alpha images taken here at Helio Research as well as a Big Bear image from this morning. I can confirm that this occured after 21:55 UT yesterday, the 24th, and before 14:38 UT today, the 25th. A new filament also seems to have formed on the west/southwest side of the sunspot. I have put two H-Alpha jpeg images, of before and after this dissapearance and formation, on our ftp site at: http://www.helioresearch.org/archive/helio/sigmoid Pete Zink Observer and Technician Helio Research Solar Observatory