***** File ACKNWLDG.TXT ACKNOWLEDGEMENTS Malcolm B. Niedner, Jr. Large-Scale Phenomena Discipline Specialist Laboratory for Astronomy and Solar Physics Code 684.1 NASA--Goddard Space Flight Center Greenbelt, MD 20771 This has been a vast enterprise. o Setting up a worldwide network of participating observatories with wide-field imaging capability; o collecting thousands of the resulting images of Halley's Comet, and o digitizing a respectable fraction of them with computed astrometry; o constructing a database to record all incoming material and track all images while being processed; o checking all the "metadata" about the imagery against observing logs, letters from observers, and other listings; o generating film copies of the best plates for publication in a photo- graphic atlas of the 1985--1986 apparition; o running tests on data compression techniques for use on compact disc-- read-only memory (CD-ROM); o making decisions about content and format of tables, indices, and text files appropriate for the CD-ROMs; and, finally, o depositing the final data on CD-ROM in compressed form, were but a few of the things which happened in my Laboratory during the 1980s as a result of its involvement in the Large-Scale Phenomena (L-SP) Discipline of the International Halley Watch (IHW). L-SP was a project so large that it nearly defeats any attempt to describe it fully, accurately, and fairly. It is, however, an absolute joy to try, for this is really a tribute to the people I was associated with who helped make this happen, who made the endeavour a success. ------------------------------- First, and very important to state early, thanks go to all the many observers in the Large-Scale Phenomena Network (LSPN) who submitted to us their precious plates, films, and prints of a unique celestial happening, not only for archiving but for physical and scientific safekeeping. As many of our network colleagues as possible are listed in the LSPNOBS.TXT file in this directory. It sounds terribly trite to say, but I can think of nothing more true than "it wouldn't have happened without you." Thank you for your competence, your dedication, and, in the body of the imagery you submitted to the IHW/L-SP Discipline, your contribution to the advancement of science. My colleagues and fellow Large-Scale Phenomena Discipline Specialists (DS) JOHN C. ("Jack") BRANDT and JURGEN RAHE were highly instrumental in the late-1970s and early-1980s in helping develop the very concept of the IHW, and of what turned out to be the "Large-Scale Phenomena Network". Interestingly, a year or two before there was a formal IHW, Jack, Jurgen, and I had sent out letters to hundreds of international observers asking for cooperation in a wide-field network to support any possible NASA mission to Halley's Comet. The mission didn't become reality, but Louis Friedman's idea--the IHW--did. Jack and Jurgen were especially helpful through the years in supplementing whatever efforts the writer was able to mount to secure important imaging material from the LSPN observers. I wish to take special note of the fact that on several occasions I was "striking out", but either Jack or Jurgen had that "magic touch" and saved the day. Thanks go to both of them for continuing, steadfast support to make the project as successful as it seems to have been. While the digital L-SP archive has been assembled at NASA/GSFC, I have also been involved, and have enjoyed, working with Jack and his colleagues at the University of Colorado on the construction of a wide-field photographic atlas of Halley's Comet, 1985--1986. There are several remarkable individuals employed by the ST Systems Corporation (STX) in Lanham, MD who worked on the L-SP DS Team as archivists and software specialists, and who deserve much of the credit for whatever success has accompanied this project. BARBARA B. PFARR and ARCHIBALD ("Archie") WARNOCK III have each served as Task Leader on the contract between STX and NASA/GSFC for the Large-Scale Phenomena archiving work, and any sane person (which I think I am) would trumpet their accomplishments loudly. Much of the bedrock structure of our operation at NASA/GSFC was either devised, or was heavily influenced, by ARCHIE WARNOCK, our Senior Software Specialist. A good example is the code I still find remarkable--that which computes a rigorous astrometric plate solution at the microdensitometer before the plate scan has even commenced! When our team speaks the software elements by name--SETUP and ASTROM--we think of Archie immediately, and for very good reason. Perhaps as much as any other, those pieces of software were the essential core in making our digital data "useful" to the outside community. Archie is also a wizard with personal computers (PCs), CD-ROMs, and database management systems, and I think all of us on the Team have learned a little more in these areas just being around him and absorbing a fraction of what he knows. More important, many of the IHW's good ideas about how to deposit the Halley data on CD-ROM (in compressed form for L-SP) were first heard from his lips. Regrettably, space (and not my memory) does not permit a listing of all his contributions. Suffice it to say that Archie is an "ideas man" whose expertise in many vital areas areas went far beyond the boundaries of Large-Scale Phenomena work, and into the larger arena of the IHW project as a whole. The IHW benefited a great deal. BARB PFARR, our Archive Manager, took over the Task Leader position from Archie when he became heavily involved with the GHRS experiment on Space Telescope, but the impression would be totally false that Barb was not already a tremendous leader in almost all aspects of the operation. Incredibly, she was a leader at the same time she was keeping herself immersed in the project's most minute details. I would be very hard-pressed indeed to think of an individual more capable than she of keeping a large, complicated project running as smoothly as it did. By anticipating possible problems well in advance, many of them were skillfully avoided. When hurdles did come up, Barb didn't simply come to me with them, she presented possible solutions and made recommendations. You name it--the development of high-level code, the skillful assignment of tasks to others (called good management), the constant verification of data quality, the resolution of thorny problems with some of the images, keeping the DS fully-informed and, when necessary, "on track"--Barb did it all (digitizing over 200 images herself, by the way), and it still leaves me wondering "How, Barb, how?" How did one person--how COULD one person--do all you did? Working weekends would be the quick answer; being good at what you do AND dedicated is closer to the truth. I will come back to the STX personnel momentarily. First a word about a NASA/GSFC colleague in Code 684, DANIEL A. KLINGLESMITH III. From time to time during the IHW's long history we had meetings called "SAM i", where SAM = Software (and) Archive Meeting and "i" is a running index (i=I,II,...V,..). It is fair to say that Dan is the "Father of SAM". It was primarily his idea, a long time ago in 1983, that the success of the IHW would depend not only on the amount of data collected by the various disciplines, but also on how we archived the data and deposited them on CD-ROM. SAM I was held at the NASA/Goddard Space Flight Center in 1983, and Dan called and chaired that two-day meeting at which many of our "archiving principles" were established. It was a nice piece of work and it led to many future SAMs (the final "i" is not known, but is not small). A huge accomplishment of Dan Klinglesmith's, the one for which I will be eternally grateful, has been rather recent. It was he who reasoned out how we were going to take our 1,439 digitized images of Halley, deposited on so many unsorted "archive tapes", and: get them "on- line" in one location (an IBM mainframe), compress them, store the compressed images "on-line", and write the images in chronological order to high density magnetic tapes (all this was required for premastering the L-SP images). If the reader knows how large 20 gigabytes of data are in the context of on-line storage, then perhaps the magnitude of Dan's achievement becomes clear. No one on this project grew or flourished more than JOAN E. ISENSEE of ST Systems Corporation. It is hard to express adequately my admiration for Joan, who went from being my NASA Branch secretary to not only our expert on "Datatrieve" (our database system), but also our top digitizer of Halley images and our most invaluable day-to-day programmer. Joan patiently set up, then scanned, 352 plates of all sizes and descriptions; her plate solutions were consistently as good as anyone's. Having scanned 160 Halley plates myself (and being easily able to remember how tiring it was) makes me really appreciate her dedication and her achievement. As for her programming skills, nearly every time I asked that Datatrieve do something a little better or a little different, Joan took on the job and completed the task with consummate skill. Joan was also the member of our Team who was primarily responsible for monitoring the enormous flow of magnetic tapes associated with converting the original microdensitometer data to FITS format. Along with Barb Pfarr, she was a key person in displaying our scanned images on an image-processing workstation, with particular emphasis on the excellence of the plate solution. I am extremely grateful for all Joan has meant to our success, and wish her well as she begins a promising new career. EDWIN J. GRAYZECK, of Interferometrics, Inc., has been affiliated with the L-SP Discipline for years and has been a pleasure to work with. Probably Ed's first IHW/L-SP interest was the creation of some scheme by which the many images flowing to the DS Team in 1985--1986 could be "browsed" in an efficient manner, that is, without having to pull plates, films, and prints out of jackets. I remember Ed "frame-grabbing" plates and prints with a CCD camera, depositing them on videotape, and playing them back on a VCR; it was a noble concept which would come to full fruition years later with the "browse images" deposited on CD-ROM along with the full-resolution, compressed L-SP images. Bigger and better things were coming as Ed began to get involved in the relatively new technology of CD-ROM, especially as it related to the IHW. Through sheer force of newly-acquired expertise, Ed began to be recognized within the IHW project as a very key player in the assembly of the final CD-ROM archive. As these Acknowledgements are being written, Ed is heavily involved in pre-mastering the first of the compressed image (L-SP) discs. The entire IHW owes him a huge debt of gratitude. NANCY E. PODGER, who left us in 1988, worked with STX for several years on the L-SP task. "Nanc" really made her mark by taming our database system and making it more relational than it was upon installation. She accomplished this by writing a great number of Fortran programs which allowed the user to perform certain key functions within the "domains" of the system. Well over 3,000 images were eventually entered into our database, and it was Nancy's very well-designed series of menu-driven "log-in pages" that made for an accurate entry of the image metadata onto the computer. The software which writes the so-called "printed archive" was originally written by Nancy, and recent changes to it mostly treat special cases. It was a pleasure having Nancy Podger on our Team, and her good work is felt to this day as we finish the L-SP part of the IHW archive. MICHAEL R. GREASON, also employed by STX, was the person who kept the microdensitometers running, and he did his fair share of the scanning. Anyone who thinks that a microdensitometer is capable of a 4096x4096 (pixel) scan once or twice a day for four years, without breakdown, is sadly mistaken. The trick is to minimize the "down time" by anticipating breakdowns and replacing parts before they wreak havoc with the machines. Mike really kept on top of things in the "PDS Room", and if the "up time" wasn't quite continuous, it was close enough to being so that we met our goals with something to spare. Back in the very early (pre-data) years of the IHW, we adopted the goal of scanning 1,000 good plates of Halley. In reality we scanned more than 1,200 images, with several hundred more coming in digital form from a few observers. That we topped 1,200 scans is due in part to Mike keeping us going on numerous occasions when things looked hopeless. Thank you, Mike. JOHN M. BOGERT III, of NASA/GSFC, worked closely with Dan Klinglesmith on the immense problems associated with storing and manipulating our large images on the IBM 3081 mainframe computer. As I said in Dan's write-up, 20 gigabytes of data pose some daunting challenges if one wants the data to be "on-line" in some sense. John's insight into the world of mainframes (which many of us have drifted from) was a key ingredient in us doing what we wanted with the 1,612 digital data files of Halley and calibration objects. It needs be said loudly that John's programming did not simply move the images around in the IBM archiving system during the various processing steps associated with final preparation of the data; just as important, he wrote the previous pixel code (PACKER.FOR) which compressed the images. When we reached the critical phase of data preparation in the last months preceding CD-ROM generation, it was comforting to have pros like John and Dan at the helm. The following individuals made important contributions to the success of the L-SP Team and are thanked here. STEVEN B. HOWELL, then of STX, wrote some code during 1986-87 which allowed us to display and manipulate images at the workstation level; he was also a regular scanner of images early in our pipeline. WAYNE B. LANDSMAN and other STX employees working on the Ultraviolet Imaging Telescope (UIT) project have developed an extensive image processing system in IDL called "MOUSSE"; much use was made of MOUSSE by the L-SP Discipline after Steve left the project, and it is a pleasure to thank Wayne and the UIT personnel for the user of their software. LYLA L. TAYLOR, also then of STX, worked on our Team during 1988-89. One of Lyla's major responsibilities was to "Gould-check" the FITS-formatted images for accuracy in the astrometric plate solution. In addition, Lyla probably scanned more images per unit time than anybody, except perhaps Joan Isensee and JANET SINCLAIR. Janet, of the Royal Greenwich Observatory, accompanied her husband Andrew to NASA/GSFC during his 1988 summer faculty appointment. Rather than sit in an apartment watching American soap operas, she decided to work, even if it was without compensation. In that one short summer she scanned 50 images, the oversize difficult ones at that. JINNY RHEE, KANAV BHAGAT, and JENNIFER GAGLIARDI were three Summer students who worked with us during the Summers of 1987-1989; they were a breath of fresh air as they gladly took on some of the tasks that had the rest of us gasping. MARGARET ("Meg") PERKINS was a Summer student who came to work with us in mid-May of 1990; her tragic and untimely death by murder at the age of 22 shocked and saddened her friends at NASA/GSFC. Meg's three weeks with us were characterized by her special achievement and dedication, and she will always be remembered. CHRISTOPHER A. ("Kit") HARVEL was involved many years ago in thinking through some of the requirements an archive system would have to have to handle our eventual data. WALT BELL, of NASA/GSFC, helped Mike Greason keep the microdensitometers going. Many thanks to one and all of you. I would like to acknowledge the very substantial contributions of three university colleagues who either contributed data or ideas to the Discipline. WILLIAM LILLER, of the Instituto Isaac Newton in Vina del Mar, Chile, was my closest collaborator in the L-SP "Island Network", a small set of 5 remote sites around the world which, equipped with portable (8"-class) telescopes in the hands of competent observers, were thought capable of greatly filling in the gaps of coverage caused by the world's great oceans. Bill conducted an incredible post-perihelion campaign from Easter Island, submitting 35mm images of such quality that we digitized a large fraction of them for placement on these CD-ROMs. FREEMAN D. MILLER, of the University of Michigan, secured some of the best and most voluminous plate material we received from any observer. Freeman observed on the Curtis Schmidt at CTIO during the post-perihelion interval, and like Bill Liller (who had the pre-perihelion Curtis run, by the way), was possessed of tremendous weather and unbelievable consecutive-nights- with-plates statistics. PETER D. USHER, of the Pennsylvania State University, did not contribute data, but the most detailed thinking yet on an important concept: how to use standard stars in wide-field plates as absolute calibrators of the H & D curve of uncalibrated plates. We hope at some point in the near future to use Peter's techniques to analyze the changing rate of injection of ions into the plasma tail. Many thanks go to these three individuals for their contributions to the L-SP Team. No Acknowledgements would be complete without mentioning the excellent relationship which has existed between my Team and the IHW Lead Center at the Jet Propulsion Laboratory (JPL). To RAY NEWBURN, MO GELLER, ZDENEK SEKANINA, and MIKAEL ARONSSON, I say it's been good fun and we've enjoyed it. Thanks for all your encouragement and support through the years; you've done a good job and should be proud of it. ---------- Last, but most important to me personally, I would like to dedicate whatever contribution I made to this project--whatever share of the success is mine--to the memory of my dear Mother. MBN, Jr. June 11, 1990