June 21, 1999 Piet Martens CHIEF OBSERVER'S REPORT for Week 25 14-Jun-99 to 20-Jun-99 GENERAL Activity was moderately high, with a C flare in AR 8585, observed by SXT, and an M flare on the NW limb, that SXT did not observe because flare mode was not triggered due to the South Atlantic anomaly, and because SXT was observing AR 8585 in ARS2. The activity in AR 8585, target of the First Max Millennium Campaign, has been disappointingly low. There were 5 more flares over the weekend, with SXT in ARS1, two C flares on 19-Jun-99 and two C and one M on Sunday 20-Jun-99. The M flare occurred in SXT night. SXT TECHNICAL No problems. Last week's slight increase in straylight has subsided. There may be a small increase in dark current resulting from overexposure during the M-class flare. There is also a glitch due to the same event. SXT SCIENCE For Web material see Current Week: http://www.solar.isas.ac.jp/sxt_co/SXTweekly.html Current Week: http://www.solar.isas.ac.jp/sxt_co/990618.html Index: http://www.solar.isas.ac.jp/sxt_co/index.html This week's science nugget shows a humongous polar crown filament eruption, the related CME, and postflare loop images, with H-alpha data from Big Bear and Meudon, He 304 from EIT, CME observations from LASCO C2 and C3, and, last but not least, Soft X-ray postflare arcade images from SXT. CAMPAIGNS SXT participated in the first week of the First Max Millennium campaign, together with TRACE, SOHO, and 27 ground based observatories on 6 continents (all except Antarctica). SXT followed the target, AR 8585, in ARS2 from 15-JUN-99 19:36 UT until 18-June-99 15:13 UT. (See: http://solar.njit.edu/mmoc/). By default SXT participated in the campaign "Dynamics and Structure of Large Sunspots" (SOHO JOP108), by CDS, TRACE, MDI, and La Palma, since AR 8585 was also the target for that. For more information on campaigns, see: http://sec.noaa.gov/solcoord/solcoord.html For SXT plans, finger campaign@isass0.solar.isas.ac.jp. PERSONNEL No change. SEMINARS Piet Martens gave a seminar on "The Nature of Moss", that generated a strong interest in the analysis of joint SXT-TRACE observations. **************** SXT TABLE PLAN, WEEK 26 (21-Jun-99 to 26-Jun-99) The two week Max Millennium flare campaign will continue. SXT will continue to point to the region designated by the campaign coordinators. On Thursday June 24 SXT will support the SERTs rocket flight observations. ________________________________#_______________________________ JST Day UT Start Time Pass Table ID Monday 21-JUN-99 15:57 3 990621 P3 ARS2 STMAX01-2* Tuesday 22-JUN-99 12:46 2 990622 P2 ARS2 DAMAX01-2 Wednesday 23-JUN-99 13:01 2 990623 P2 ARS2 DIMAX01-2 Thursday 24-JUN-99 16:42 4 990624 P4 ARS0 SERTS-0* Thursday 24-JUN-99 18:25 5 990624 P5 ARS2 STMAX01-2* Friday 25-JUN-99 11:47 2 990625 P2 ARS2 STMAX01-2 Saturday 26-JUN-99 12:02 2 990626 P2 ARS1 STMAX01-1 "MAX01" stand for first Max Millennium campaign, the extensions -1 and -2 stand for the ARS1 and ARS2 modes. "SERTS-0" stands for SERTs rocket flight support, most likely in ARS0. As previously, the (*) in a table name means that the UT date and the JST date don't match. This plan is subject to change. Continuing requests: KSC & SSOC Tohbans: If any KSC passes are likely to be cancelled (for example due to a typhoon) or an SXT table cannot be uploaded for some reason, please telephone and e-mail the Chief Observer immediately. (sxt_co@isass0.solar.isas.ac.jp, copy to sxt_st@flare2.solar.isas.ac.jp). SSOC Tohban: On the weekly visible diagram, please mark the official five passes first and then cross out those passes that will be given to other satellites. That way we can keep the numbering straight in the Yohkoh software system. SSOC Tohban: SXT operations do not currently include terminator off- pointing. It is unnecessary this week to ask the SXT Chief Observer for terminator off-pointing information. KSC Tohbans: In general flare mode supersedes table upload, ie if a flare is in progress please do not upload a new table, and contact the chief observer. Normally it is OK to go ahead with the planned table without change on the next pass, if it is available. Chief observers should keep an eye on this.