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March 1996                                 Volume 4, No. 2


This is an electronic newsletter edited by the IUE Data Analysis Center intended to inform the numerous remote and local users of the IUEDAC software of recent software updates and project changes.

In This Issue

ESA Announces September end of orbital operations support
IRAF/FITS wavelength-flux file
new USER account quotas

  • Uh-oh! IUE Suffers Gyro Failure!
  • On the evening of March 5, during normal spacecraft house-keeping operations, the Sigma 5 ground computer (for reasons at present known only to itself) sent three anomalous commands to IUE in succession. One of those commands in effect turned off the electronics for the gyro package, causing the two functioning gyros to spin down. When the electronics was reactivated, one of the gyros did not resume operation. At present, Operations Control Center personnel have successfully transferred IUE control to the one-gyro system and are solving a few related technical problems, and OCC, VILSPA, and NASA staff are considering options for the future. The one-gyro system is useful only for those targets having bright (say 8th magnitude or brighter) guide stars in the Fine Error Sensor field of view when the target is in the desired science aperture. The DAC will keep the community appraised of the situation (readers are particularly encouraged to check the IUE Web pages).

    This anomaly follows the recent announcement by ESA Science Director Roger Bonnet that ESA did not plan to fund VILSPA IUE orbital operations support beyond September of this year. This decision was made in response to financial constraints at ESA. The text of the ESA announcement can be found at


  • IUEDAC Software and Hardware Updates
  • Recent Software Changes (since 04-Jan-1996)
    The DAC added a new routine to the experimental library called WFIRAF which stores wavelength and flux vectors in an IRAF compatible FITS file.

    The DAC added a new version of IUEASTRO to the experimental library which corrects a problem when converting or precessing degrees between values of 0 and -1.

    The and files have been changed in order to simplify IUEDAC software installation at remote nodes. The changes should be transparent to the users.

    The disk quotas for IUE USER accounts have been increased to 50000 VMS blocks.


  • DAC Libraries Updated
  • The libraries for the production and experimental software were updated for the anonymous ftp distribution in early February. An updated version of the Merged Log should be available in about a week. The VMS libraries can be found at in the IUEDAC subdirectory. Links to the Unix, Ultrix, PC (Windows), and Macintosh libraries can be found on the IUEDAC web page.

    The distribution form of the Mac software has also been changed to (hopefully) simplify the installation. These files are now stored as self-extracting archive files in BinHex4 format. They should be transferred in ASCII format and then converted from BinHex4 format with an appropriate converter; one can be found in the archive program Compact Pro under the Misc menu. The files can then be extracted just by clicking on their names.


  • User-developed Software
  • Hey, we're not proud! Who can afford to be now days? If you have developed software to analyze IUE data that you think might be useful to other users, and if you have an interest in making this code more generally available, the DAC would like to hear from you! We are considering establishing a subdirectory specifically for such contributed code. IUE has traditionally benefitted greatly from this kind of user input. Please contact Randy Thompson or Rich Arquilla.


  • IUE and Education
  • During November through February, the IUE Project conducted an educational project providing students with hands-on experience in spacecraft operations and satellite astronomy. The brain-child of IUE Project Scientist Dr. Yoji Kondo, and CSC's Peter Perry and Terry Teays, the project made use of the time during which the IUE spacecraft is parked for eight hours/day. Four students, two college and two high school, were trained in conducting basic science operations with IUE. Terry Teays was the instructor, with assistance from other IUE Project staff, Judy Pepoy and Jim Caplinger, as well as Fred Bruhweiler of the Catholic University of America. After training "off-line", the students conducted real-time science operations during several of the US Maintenance Shifts. They performed spacecraft maneuvers, identified and acquired targets, obtained spectra, and archived the data.

    In addition to these activities, the students received lectures on spacecraft operations in general, spacecraft hardware, ultraviolet astronomy, and IUE data reduction and analysis. They also were given lectures on the targets which they observed, so that they would understand the nature of the objects and the scientific relevance of the ultraviolet spectra.

    The students' "final exam" was to conduct a shift during which the Director of Goddard Space Flight Center, Joe Rothenberg, observed them at work. They did an excellent job, and had a good time as well. It was especially rewarding to see the excitement of NASA's space science being communicated to these young people.


    Dr. Richard Arquilla
    Mr. Randy Thompson
    Mr. Jim Caplinger
    Dr. Cathy Imhoff
    Ms. Karen Levay
    Dr. Joy Nichols
    Dr. Terry Teays

    Back to the IUE Data Analysis Center

    Web Curator

    Mr. James Caplinger, Computer Sciences Corporation

    Responsible NASA Organization/Official

    Dr. Don West, IUE Operations Scientist