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EXPANDING V I S I O N SPACE TELESCOPE SCIENCE INSTITUTE | ANNUAL REPORT 03 EVTHE CONTINUING OLUTIO EVOLUTION OF THE HUBBLE SPACE TELESCOPEN EVTHE CONTINUING OLUTIO EVOLUTION OF THE HUBBLE SPACE TELESCOPEN E V O L U T I O N STEVEN BECKWITH he year 2003 began with the tragic loss of the space shuttle Columbia and its crew of seven astronauts on February 1st. It ended with Hubble returning data of unprecedented quality and size as a result of the instrument upgrades made by TColumbia’s crew on its last mission prior to the disaster, Servicing Mission 3B (SM3B). In between, we saw the continued growth of new ideas to use Hubble to understand the cosmos, stimulated by its evolution as the world’s only serviceable space telescope. Almost 60% of Hubble’s observing time in the current cycle uses the Advanced Camera for Surveys, installed during SM3B in April 2002. The growth of interest is only in part because ACS is new. The more important reasons are that Hubble can uniquely resolve the small structures of galaxies in the early universe, as demonstrated first with the Hubble Deep Field (HDF) observations in 1996, and that understanding galaxy formation has moved to center stage in astronomy as a key problem to be solved. Four major surveys of distant galaxies are complete or underway: the Great Observatories Origins Deep Survey (GOODS), Galaxy Evolution from Morphologies and Sprectral Energy Distributions (GEMS), Cosmic Evolution Survey, and the Hubble Ultra Deep Field (HUDF). These in turn were stimulated by the discoveries of the 1990s involving Hubble and the big ground-based telescopes. EVOLVINGEXPANDING VISION PERSPECTIVE The discovery of the acceleration of the universe in the late 1990s also This supple transition from one area to another is characteristic of a carved out a unique new role for Hubble. Its ability to measure the magnitudes of distant complete observatory, which is a general-purpose facility, not designed to answer a supernovae make it the telescope of choice for understanding the era when the universe specific scientific question but rather to investigate many. Hubble’s ability to improve its transitioned from slowing down to speeding up in its expansion. The Near Infrared Camera instruments through servicing gives it added agility, allowing us to tailor its strengths to and Multi-Object Spectrometer, restored to life by the astronauts during SM3B, is essential the most important problems of the era. As science evolves, so too does Hubble, keeping it for these observations and underscores our ability by means of servicing missions to adapt on the cutting edge for decades. None of NASA’s other missions has been able to evolve so Hubble to the important science of the day. adroitly as Hubble. The new instruments will enter the hunt for extrasolar planetary systems with Of course, this continuing evolution makes the operations more complex a series of observations scheduled in Hubble’s Cycle 12 to search for occultations by than would be those of a single-purpose facility. Over the course of 20 years, the Institute planets surrounding stars in the bulge of our Galaxy, a search for which Hubble is uniquely will go through four generations of computing systems and software. It will create entirely suited. Discovered in the mid-1990s, extrasolar planetary systems have become a central new architectures for its data delivery systems as the data rates increase by orders of 5 theme of modern astrophysical study as well as a motivation for the next generation of magnitude. It will produce new instrument handbooks, methods of calibration, space telescopes. visualization and analysis tools, and even public outreach products as we move into the era of IMAX and HDTV. But the incremental cost of these complex operations is repaid many H u b b l e w a s designed for an entirely different set of scientific problems than times over in the value returned to science. those it is solving now. Most of the original problems were solved in Hubble’s first decade, and it is now concentrating on the most important topics of today, none of which were The staff at the Institute is proud to be part of Hubble’s constant evolution, developed or even imagined during Hubble’s design. Yet Hubble is now a dominant force in exemplified so well by the successes of 2003. We hope you enjoy what you read in our these new topics, in some cases uniquely so. Annual Report, a mixture of fascinating science and the people and systems needed to bring it to you. As you ponder the wonders of the cosmos brought to you by Hubble, think of the great engineers at NASA who built the telescope, the courage of the astronauts who improve it, and the hard work of the people at the Institute who will ensure it continues as one of the most important facilities in the history of science. 19 Hubble is launched aboard space shuttle Discovery. After analyzing Hubble’s first pictures in June, astronomers discover that the telescope has “blurred vision,” caused by a slight distortion in the 2.4-meter primary mirror. EVOLVING 90 The telescope resolves a ring of material around Supernova 1987A. NEWS NEWS 19 90 91 Hubble’s detection of blue straggler stars in the core of a globular star cluster supports the theory that they result from stellar collisions and mergers. More information about ViewSpace and related projects is available at http://hubblesource.stsci.edu. “When we took you up on your ViewSpace offer, we did not know how good it was going to be for us,” wrote Judith James, planetarium director at the Brazosport Nature Center and Planetarium on the Texas gulf coast. “Dow Chemical Company came through with a generous donation for equipment large enough to do ViewSpace and an upgrade on our projection equipment in the dome. We now have a high-end graphics computer and a 42-inch wall-mounted plasma screen in our lobby viewing area…. It’s been a real magnet for us.” NEWS ViewSpace: Now Playing at a Planetarium Near You John Stoke People visit museums, science centers, and planetariums in search of connections to the universe beyond their everyday experience. They expect science to be presented in a way that informs and entertains. They tacitly assume that their local museum or planetarium has the curatorial resources necessary to keep abreast of the latest developments in science—and to keep their exhibits and programs up-to-date. In 2003, the Informal Science Education group in the Institute’s Office of Public Outreach worked to make those assumptions a reality, at least in the realm of astronomy. We developed ViewSpace, an innovative program that links the Institute to popular venues of public science education across the country. ViewSpace uses the Internet and inexpensive hardware to deliver a continuous ‘feed’ of visually rich, astronomically- themed story segments from Hubble and other space-science missions. At the venues, these segments are presented in mini-theaters set up in astronomy exhibit halls and planetarium lobbies. Images, interpretive text, digital animation, and evocative music combine to create low-cost experiences that many visitors find simply mesmerizing. Word about the availability of ViewSpace is spreading rapidly. In the first year, over 40 institutions— in communities large and small—installed ViewSpace or committed to the program. Dozens more have 7 expressed interest. Current venues include Boston’s Museum of Science, the Cleveland Museum of Natural History, the New York Hall of Science, Honolulu’s Bishop Museum, the Houston Museum of Natural Science, and the National Air & Space Museum. At the 2003 conference of the American Association of Museums, ViewSpace was awarded a Bronze MUSE Award “in recognition of the highest standards of excellence in the use of media and technology for interpretation and education in science.” One judge commented: “This was great. It was like seeing a sky show on my PC. And while the images were spectacular, it wasn’t just about the images. The content was great, too—interesting, clear, well-presented, and wonderfully illustrated with these great photos.” The wider astronomical community has discovered that ViewSpace offers a fresh, appealing way to convey its latest science results to audiences eager to receive them. We have collaborated with the Chandra, Spitzer, and SOHO missions to create educational story segments and ongoing mission updates. 19 90 91 92 Hubble identifies nearby intergalactic clouds. NEWS Independent Detector Testing Laboratory Donald Figer, Michael Regan, In 2003, the Independent Detector Testing Laboratory (IDTL) completed a critical task for NASA, the Bernard Rauscher characterization of candidate near-infrared detector technologies for the James Webb Space Telescope. On the basis of IDTL results, two Webb scientific instrument teams selected HgCdTe detectors made by Rockwell Scientific Company. The Institute and The Johns Hopkins University established the IDTL in 1999 to provide world-class testing and development facilities for astronomical detectors and associated technology. The IDTL serves the astronomical community with expertise, technical information, and facilities, and also provides training for graduate students in detector technology. The IDTL tests of near-infrared detectors for the Webb involved measuring first-order detector properties such as read noise, dark current, persistence, and quantum efficiency. These were measured as functions of environmental parameters (radiation exposure, thermal conditions, and operating modes) for two candidate detector types. The tests were conducted using the same procedures, setups, dewars, light sources, targets, electronics, acquisition software, analysis software, and staff. The completed Webb detector characterization project obtained two terabytes of data over two years from six prototype detectors during 25 cool-downs. 9 The measured performance of the Rockwell detector is impressive, with dark current as low as 1.3 e- per 1000 seconds per pixel, the lowest ever measured for an array having a long wavelength sensitivity cutoff at 5 µm.