28 December 1998 Hugh Hudson Mark Weber SXT CHIEF OBSERVER'S REPORT AND TABLE PLAN CHIEF OBSERVER'S REPORT for Week 52 21-Dec-98 to 27-Dec-98 GENERAL Yohkoh and SXT continued to perform without problems this week. Solar activity was again at a high background level most of the week, near C1. As with last week, there were only two M flares as of Saturday. A dominant active region, NOAA 8421, is being followed by TRACE and by us automatically. During the invisible orbits Friday/Saturday, an otherwise quiet S hemisphere generated a rather beautiful arcade event. SXT TECHNICAL The SXT instrument is functioning nominally. 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/981225.html Index: http://www.solar.isas.ac.jp/sxt_co/index.html This week's nugget deals with the probable discovery of a Moreton wave in the SXT data - May 6, 1998. This is interesting because it's our first good example. CAMPAIGNS There were no formal joint observing campaigns this week. SOHO, alas, is off again. TRACE is following AR8421 as are we. See the general coordination page at: http://sec.noaa.gov/solcoord/solcoord.html PERSONNEL Mark Weber ended his tour at ISAS, we hope not his last one! SEMINARS No seminars this week. Tune in again next year, please. 24 December 1998 H. Hudson SXT TABLE PLAN, WEEK 53 (28-Dec-98 - 30-Dec-98) No coordinated observations are currently planned. We will just try to get our calibrations done, then say goodbye once again to Yohkoh until Jan. 4 (first contact pass, 4-JAN-99 21:12:44 UT). ________________________________#_______________________________ JST Day UT Start Time Pass Table ID Monday 28-DEC-98 03:34 4 981228 P4 ARS1 DARKCAL Tuesday 29-DEC-98 02:08 2 981229 P2 ARS1 STD+DIFF Tuesday 29-DEC-98 05:34 4 981229 P4 ARS1 STD Wednesday 30-DEC-98 00:42 2 981230 P2 ARS1 NEWYEAR 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.