Page 1 PROGRESS REPORT THE SOLAR-A SOFT X-RAY TELESCOPE (SXT) PROGRAM (CONTRACT NAS8-37334) (for May 1995) OVERVIEW The YOHKOH Mission is a program of the Japanese Institute of Space and Astronautical Science (ISAS) with collaboration by the U. S. National Aeronautics and Space Administration and the U. K. Science and Engineering Research Council. The YOHKOH satellite was launched on 30 August 1991 from Kagoshima Space Center (KSC) in Japan. The purpose of this mission is to study high energy phenomena in solar flares and the Sun's corona. Under an international cooperative agreement, Lockheed, under NASA contract, is providing a scientific investigation using the Soft X-ray Telescope (SXT), one of the primary experiments of the mission. The SXT was developed at the Lockheed Palo Alto Research Laboratory in cooperation with the National Astronomical Observatory of Japan, and the Institute for Astronomy of the University of Tokyo. MAJOR PROGRAMMATIC ACTIVITIES IN THE MONTH A program status presentation was given to George Withbroe and Bill Wagner at NASA HQ by James Lemen and Frank Friedlaender on May 24. The review covered general programatic and science activities as well as the extensive outreach effort. A brief, one-page fact sheet about the program was also provided, and this was very well received. Discussions also covered additional outreach effort to be performed by Lockheed and MSU to make the Yohkoh data available over the Internet and to other educational institutions. The Commerce Business Daily notice for the Extended Mission was released on May 24. << Solar Activity >> The solar activity for May generally low but, as has been the case for the past few months, there were approximately two weeks of slightly increased activity. During May this activity mainly came from AR7869 and AR7870. There were only 14 C class flares reported from GOES, not exceeding C5. AR7869 was positioned nearly at the equator. At the beginning of the month there was an event at the south east limb that was probably associated with a filament eruption and/or CME, since SXT was able to observe an expanding set of X-ray loops. After the AR7869/7870 complex rotated off the disk the SXT went back to quiet Sun observations. Filament watch campaigns will continue to be attempted when the conditions are appropriate. << Campaigns >> Page 2 SXT provided planning images for the SERTS (NASA/GSFC Solar Extreme- ultraviolet Rocket Telescope and Spectrograph) rocket flight which took place on 15 May 1995 from White Sands, NM. According to L. Action, the SXT Chief Observer at the time, "the SERTS investigators were incredibly lucky! At the time of their launch. a nicely developed complex of activity centered around AR7870 was perfectly situated for their spectrograph. This region produces some beautiful sequences which should help illuminate problems of the formation of active region interconnections and neutral line arcades." It appears that the coordinated observations were very successful. The filament watch campaign was tried towards the end of the month. This campaign seeks to obtain good observations in X-rays and from the ground of a filament eruption. The method for coordination with Mees and with the Soon system has been refined, but we have not yet had the success of a coordinated observation of an actual eruption. Future plans include campaigns to observe filaments and XBPs as well as to support SPARTAN, and Ulysses' passage over the northern pole of the Sun in the coming months. << Science >> The main scientific activity of the month was the IAU Colloquium No. 153 (Magnetodynamic Phenomena in the Solar Atmosphere -- Prototypes of Stellar Magnetic Activity), which was held in Makuhari, near Tokyo, on 22-26 May 1995. There was a tremendous use of the SXT data during the meeting. Many preparations are being made by various SXT team members to present SXT results at the upcoming AGU meeting (Baltimore), SPD meeting (Memphis) and SolWind 8 (in Dana Point, Ca). << Publications>> The following is an incomplete listing of work in progress on papers and presentations that include scientists that are supported by the NASA SXT contract. - Papers Published (1) - "The Point Spread Function of the Soft X-ray Telescope Aboard Yohkoh": Petrus C. Martens, Loren W. Acton, and James R. Lemen, Solar Phys., Solar Phys. 157, 141-168 (1995) - Papers accepted (1) - "X-Ray Bright Point Flares Due to Magnetic Reconnection," L. van Driel-Gesztelyi, B. Schmieder, G. Cauzzi, N. Mein, A. Hoffmann, N. Nitta, H. Kurokawa, P. Mein, J. Staiger, Solar Physics - Papers Submitted (1) - Page 3 "Flares in Active Region NOAA 7260 (I): Overview," N. Nitta, L. van Driel-Gesztelyi, K. D. Leka, K. T. Strong, J. R. Lemen, S. L. Freeland, T. Kosugi, T. Sakurai, K. Ichimoto, Solar Physics - Presentations (1) - Active region evolution and flare activity - a case study of NOAA 7260 N. Nitta, L. van Driel-Gesztelyi, K. D. Leka, and H. S. Hudson (IAU Colloq 153) - Abstracts submitted(0) - << Public Use of SXT Images >> We continue to submit and have published our monthly article on solar weather in "Sky & Telescope". Next month this will change. Due to space constraints in the magazine, we will no longer have a monthly column. Instead, we will have inputs when there are significant events to report. We are dealing with a new editor, Barlow Pepin, who is the "Observer's Page Editor." Gary Linford continues to coordinate this activity. << Yohkoh Operations and Health >> Yohkoh and the SXT continue to function very well. No significant degradation in the instrument has occurred since the loss of the front thermal shield in 1992. SXT experienced a normal level of Single Event Upset (SEU) events during the month: SXT warm reset During week of 22-28 May Testing for the Santiago ground station was conducted during this month. During the week of 29 May JPL began to schedule Santiago contacts for Yohkoh and ASCA use. There is a strong overlap between Santiago and KSC and this helps when there is a conflict between the Yohkoh and ASCA spacecraft and for weekend operations. The combined daily usage of Santiago by Yohkoh and ASCA is not to exceed three hours total, which includes pre-calibration, post-calibration, and post-pass playbacks. Page 4 << Data Flow >> ------------------------------------------------------------------------------ Month Full Frame Images Observing Region Images Received Lost Received Lost Loss % QT FL Tot Thru Feb-93 105985 50255 385810 192719 578529 209163 26.41 Mar-93 7177 3460 25874 19537 45411 14657 24.40 Apr-93 7754 3644 34128 8352 42480 17967 29.72 May-93 8571 3950 41832 7518 49350 21971 30.81 Jun-93 7340 2589 64545 12539 77084 26299 25.44 Jul-93 8259 3650 47561 5352 52913 24213 31.39 Aug-93 7628 3638 30705 3563 34268 17436 33.72 Sep-93 6875 2899 22697 5600 28297 11252 28.45 Oct-93 7474 3657 33782 7548 41330 20104 32.72 Nov-93 8504 3864 42953 5849 48802 23896 32.87 Dec-93 5898 3047 21128 13297 34425 13001 27.41 Jan-94 6934 2804 28567 10960 39527 13746 25.80 Feb-94 7000 2840 23021 5819 28840 11257 28.07 Mar-94 7736 2627 69273 3733 73006 31464 30.12 Apr-94 6142 2741 22707 3390 26097 12338 32.10 May-94 7070 2679 25260 3040 28300 10862 27.74 Jun-94 7417 2738 36795 1996 38791 15760 28.89 Jul-94 7488 2941 50540 3275 53815 24153 30.98 Aug-94 7370 2337 35067 3993 39060 13485 25.66 Sep-94 7079 2552 25131 2855 27986 10677 27.62 Oct-94 7244 2497 25868 5884 31752 10319 24.53 Nov-94 6569 1941 26243 1956 28199 9293 24.79 Dec-94 6429 2456 26763 2583 29346 11904 28.86 Jan-95 6870 2349 26103 1699 27802 10211 26.86 Feb-95 6556 2545 23635 3825 27460 10111 26.91 Mar-95 5915 2082 21485 3448 24933 8485 25.39 Apr-95 6244 2266 22946 4493 27439 9688 26.09 May-95 6355 2411 27092 2647 29739 13547 31.30 Jun-95 0 0 0 0 0 0 0.00 Total 297883 127459 1267511 347470 1614981 627259 27.97 Number of Full Frame Images Received: 297883 Number of Observing Region Images Received: 1614981 Total: 1912864 Approximate Number of Shutter Moves/CCD Readouts: 3337566 NOTES: * The loss of images is mainly due to BDR overwrites, but there are also occasional DSN dumps which are lost. * It is common to have observing regions which contain more than 64 lines, which requires multiple exposures to make a single observing region image. This is why the number of shutter moves is larger than the number of images received plus those lost. Page 5 << Engineering Summary Table >> -------------------------------------------------------------------------------- Month Avg Dark Level # of Dark Spikes CCD Warmings Front Optical (DN) (e/sec) Over 48 Over 64 High / # Support Trans Temp /Days Temp (%) Mar-93 43.14 473.8 14047 2151 17.7 N/A Apr-93 43.13 473.4 14304 2146 23.8 / 2 16.9 N/A May-93 43.45 485.3 16405 2357 17.3 N/A Jun-93 44.03 507.2 20037 2531 16.3 N/A Jul-93 44.46 523.4 23020 2600 22.5 / 2 17.7 N/A Aug-93 44.20 513.6 21319 2598 25.2 / 3 17.2 N/A Sep-93 45.07 546.2 27469 2745 17.5 N/A Oct-93 45.40 558.6 31684 2982 17.7 N/A Nov-93 45.33 555.8 32047 3210 23.8 / 3 19.7 N/A Dec-93 45.92 578.1 38515 3101 19.2 N/A Jan-94 46.00 580.9 39074 3088 22.5 / 2 20.3 N/A Feb-94 46.03 582.1 40449 3246 19.3 N/A Mar-94 45.92 578.0 39715 3420 18.2 N/A Apr-94 45.97 579.9 41302 3721 25.2 / 3 17.8 N/A May-94 46.25 590.3 45476 3557 18.3 N/A Jun-94 45.83 574.6 39340 3547 17.8 N/A Jul-94 46.76 609.5 53417 3990 18.2 N/A Aug-94 46.98 617.6 57624 4050 25.2 / 3 18.2 N/A Sep-94 47.07 620.9 58580 4028 18.3 N/A Oct-94 47.34 631.3 64974 4346 19.0 N/A Nov-94 47.64 642.4 70877 4703 20.4 N/A Dec-94 47.82 649.1 74246 4917 21.5 N/A Jan-95 48.55 676.7 89758 5457 20.0 N/A Feb-95 48.70 682.1 92457 5781 25.2 / 3 20.5 N/A Mar-95 48.35 668.9 85527 5271 19.4 N/A Apr-95 48.72 682.8 93904 5627 19.1 N/A May-95 48.76 684.4 94721 5850 18.9 N/A Jun-95 N/A N/A N/A N/A 0.0 N/A NOTES: * The dark current calculations are using full half resolution 2.668 sec images not taken in during the SAA. The dark current rate assumes a "fat zero" of 30.5 DN and a gain of 100 e/DN. * The entrance filter failure of 13-Nov-92 eliminated the capability of taking optical images, so the optical transmission is not available after Nov-92. It also caused an increase in the dark current signal, however some of the increase shown here is an increase in the readout noise and is not a function of exposure duration. Page 6 << Personnel Travel >> SXT Foreign Travel between 1-MAY-95 and 31-MAY-95 ACTON 1-MAY-95 * 28-MAY-95 28 (total of 28 days) HUDSON 1-MAY-95 * 31-MAY-95 * 31 (total of 31 days) LEMEN 1-MAY-95 * 3-MAY-95 3 (total of 3 days) NITTA 20-MAY-95 31-MAY-95 * 12 (total of 12 days) SLATER 2-MAY-95 31-MAY-95 * 30 (total of 30 days) WUELSER 1-MAY-95 * 5-MAY-95 5 (total of 5 days) STURROCK 1-MAY-95 7-MAY-95 7 (total of 7 days) ---------------------------------------------------------------- Grand Total of 116 days for 7 people NOTE: The "*" signifies travel that actually ends after 31-MAY-95 SXT Foreign Travel between 1-JUN-95 and 30-JUN-95 ALEXANDER 4-JUN-95 30-JUN-95 * 27 (total of 27 days) HUDSON 1-JUN-95 * 3-JUN-95 3 10-JUN-95 28-JUN-95 19 (total of 22 days) LINFORD 20-JUN-95 30-JUN-95 * 11 (total of 11 days) NITTA 1-JUN-95 * 23-JUN-95 23 (total of 23 days) SLATER 1-JUN-95 * 2-JUN-95 2 (total of 2 days) METCALF 13-JUN-95 30-JUN-95 * 18 (total of 18 days) ---------------------------------------------------------------- Grand Total of 103 days for 6 people NOTE: The "*" signifies travel that actually ends after 30-JUN-95 Respectfully submitted, James R. Lemen Frank M. Friedlaender Page 7 ------------------------------------------------------------------------------- NASA REPORT DOCUMENTATION PAGE (IN LIEU OF NASA FORM 1626) --------------------|--------------------------|------------------------------- 1. REPORT NO. | 2. GOVERNMENT | 3. RECIPIENT'S DR-01 | ACCESSION NO. | CATALOG NO. --------------------|--------------------------|------------------------------- 4. TITLE AND SUBTITLE | 5. REPORT DATE Monthly progress report - for the month of | 10 June 1995 May 1995 |------------------------------- | 6. PERFORMING ORG | CODE: O/91-30 -----------------------------------------------|------------------------------- 7. AUTHOR(S) | 8. PERFORMING ORGANIZA- J. R. Lemen | TION REPORT NO: F. M. Friedlaender | |------------------------------- -----------------------------------------------|10. WORK UNIT NO. 9. PERFORMING ORGANIZATION NAME AND ADDRESS | Lockheed Palo Alto Research Labs B/252 |------------------------------- Solar & Astrophysics Laboratory O/91-30 |11. CONTRACT OR GRANT NO. 3251 Hanover Street, Palo Alto Ca. 94304 | NAS8 - 37334 -----------------------------------------------|------------------------------- 12. SPONSORING AGENCY NAME AND ADDRESS |13. TYPE OF REPORT AND Marshall Space Flight Center (Explorer Program)| PERIOD COVERED Huntsville Alabama 35812 | Progress report for the month | of May 1995 |------------------------------- |14. SPONSORING AGENCY | CODE MSFC / AP32 -----------------------------------------------|------------------------------- 15. SUPPLEMENTARY NOTES ------------------------------------------------------------------------------- 16. ABSTRACT The SOLAR-A Mission is a program of the Institute of Space and Astronautical Science (ISAS), the Japanese agency for scientific space activity. The SOLAR-A satellite was launched on August 30, 1991, to study high energy phenomena in solar flares. As an international cooperative agreement, Lockheed, under NASA contract, is providing a scientific investigation and has prepared the Soft X-ray Telescope (SXT), one of the two primary experiments of the mission. --------------------------------------|---------------------------------------- 17. KEY WORDS (SUGGESTED BY | 18. DISTRIBUTION STATEMENT AUTHOR(S)) Solar-A, X-ray, CCD, | Space Science, Solar Physics ------------------------|-------------|----------|-----------------|----------- 19. SECURITY CLASSIF. | 20. SECURITY CLASSIF. | 21. NO OF PAGES |22. PRICE (OF THIS REPORT) | (OF THIS PAGE) | | None | None | 7 | ------------------------|------------------------|-----------------|----------- For sale by: Superintendent of Documents, U.S. Government Printing Office