WEEKLY ACTIVITY REPORT - WEEK ENDING MAY 15, 1992 FROM: D. P. Cauffman O/91-30 B252 X43390 CONTRACT ACTIVITY SXT PROGRAM The Osaka meeting of the Astronomical Society of Japan takes place this week. There are about 50 papers in the solar sessions (more than ever before), and 35 or so of these are some way involved with Yohkoh. The drafts of the collection of initial Yohkoh papers to be published in PASJ are appearing daily. On 20 April at around 2300 UT SXT observed a fantastic hair-pin shaped expanding loop on the SW limb that was superbly recorded in H-alpha, Fe XIV and white light at Norikura Observatory. The x-ray loop extended at about 400 km/sec and we expect (although the careful overlays have not yet been done) the H-alpha to be nestled inside. SXT PI and experienced observer, T. Hirayama, first called this a surge, but upon closer examination clear loop threads are seen in the H-alpha, so now it is called a filament eruption. This is probably, therefore, a CME and is particularly interesting because we see it end-on, accounting for the narrowness of the H-alpha and x-ray features. Great discoveries proliferate daily. Dr. Hugh Hudson of the University of Hawaii and Dr. Loren Acton (O/91-01) found that the umbra of the small sunspot which was the site of the action of the 15 November 1991 X-flare actually moved about 3 arcsec north during the 8 minutes of the impulsive flare activity. This corresponds to a motion of 4+ km/sec. You may recall that this was a white light flare. Hugh Hudson measured the peak intensity of the brightest kernel at 30% brighter than the 4310 A photosphere! This represents a whopping amount of energy. The wonders of this flare never seem to cease. The Lockheed team is now set up on LaPalma with the SOUP/OSL tunable filter system. They do their best to observe the same regions as SXT has chosen and plan to continue their campaign until July. Of course, Mees Solar Observatory continues to devote their work to Yohkoh joint observing, and the Imaging Vector Magnetograph is now coming on-line. Hiraiso Observatory is taking digital high-resolution H-alpha of superb quality on the Yohkoh observing region and Norikura and Hida observatories jointly observe whenever the weather permits. LA PALMA OBSERVATIONS DURING THE SPDE ROCKET FLIGHT Dr. Dick Shine and Igor Zayer of O/91-30 have been observing in La Palma, Canary Islands, in coordination with the SPDE rocket flight. Frequent fax and e-mail communications with LPARL and with Dr. Loren Acton in Japan kept them informed of the target region and launch window, which started at 14:26 UT. The observing day was very cloudy in La Palma, but some hazy breaks began appearing the cloud cover about 13:30 and observing started at about 13:52. Most of the images were cloudy or fuzzy, but a few were sharp. Observing continued after the flight in improving weather and seeing. These images should produce good context measurements for the rocket and SXT observations, showing the magnetic state of the photosphere and low chromosphere of the target active region. The pointing included a bright region of emerging flux limbward of the main region, which we hope coincides with one of the rocket exposure sequences. SPARTAN ROCKET PROGRAM On 27 April, the members of the O/91-30 Solar Plasma Diagnostic Experiment (SPDE) development team, Dr. Marilyn Bruner, Dr. Bill Brown, Mike Finch, and Kevin Appert, and later Wes Brookover, departed for the White Sands Missile Range (WSMR) for the purpose of integrating the science payload with the payload control system and the launch vehicle. The normal allocation of time to achieve this integration is about 3.5 weeks. In order to meet the require- ments for participation in CoMStOC, a joint solar observing program with other ground-based observatories, the launch was set at 12 May. The team worked very hard, and with the full and able participation of the launch team at WSMR, managed to complete the integration task in 2 weeks. The following message was received from Dr. Bruner this morning, 12 May: The SPDE payload was launched at 1426 UT as planned. Acquisition was at T+160 sec; a little late, but a really welcome sight. We executed two full sequences of exposures with all four cameras, the first located on the trailer spot, and the second about 12 to 16 arc seconds closer to the West Limb. The third sequence was started at the next position (again about 12-16 arc seconds closer to the W limb) and took several exposures before being terminated by loss of fine pointing at T + 420 sec. All payload systems appeared to function normally, and it looks like we got a good 'chute. Telemetry was received until the recovery system pressure sensor indicated 0 elevation, at which time TM was lost. Brown, Appert and Brookover have left for the VAB where they will board the recovery helicopter. The support that we received from the Yohkoh team were absolutely crucial in the selecting of the target and the planning of the mission! Please extend my profound thanks to all the folks who helped make this happen. I'll pass more information on the results from our experiment when they become available. TECHNICAL HIGHLIGHTS THIRTY TI-J CCD'S RECEIVED FROM NASA Before the Solar-A Program at JPL was completed and before the OSL Program was postponed indefinitely, NASA procured some additional lots of 1024 X 1024 pixel uniphase CCD's from TI-Japan. The intent was to have JPL screen/qualify these devices for OSL flight use. When OSL was put on hold, NASA announced that these devices were available to requesting scientists. We (O/91-30) requested 50 devices of varying quality, and after many months received the first part of a two-piece shipment - 30 CCD's. As these are the devices used in all three of the OSL brassboards that are presently in the field (SSO on La Palma, VTT on Tenerife, and BBSO in California). They will now cover us for replacements should the need arrive. They will also be candidates for any new instrumentation that we may develop. Dr. D. P. Cauffman, Manager Solar and Astrophysics Laboratory