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: http://www.stsci.edu/stsci/meetings/space_detectors/hasan.htm
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NASA’s Astronomical Search for Origins Program Hashima Hasan, Office of Space Science, NASA Headquarters, Washington DC 20546 Introduction Science programs within NASA’s Office of Space Science (OSS) have been placed into four scientific categories or themes:
Each science theme develops a set of compelling scientific goals and a roadmap to achieve those goals through a series of flight missions. This talk outlines the roadmap for the ASO theme (Black et al, 2000; Origins homepage) emphasizing those aspects which are relevant to the present workshop. In particular, the Large Telescope Systems Initiative (LTSI) program is presented. LTSI will address the technology needs of future missions and is one of the programs through which detectors will be developed. The need for high performing detectors required to achieve the breakthrough science envisaged in long term visionary missions is well recognized. The Origins Roadmap The two defining questions of the ASO science theme
The hierarchical structure of the ASO plan begins with the two defining questions, which are then translated into four goals, eight objectives, and sixteen investigations (Figure 1). The bottom of the pyramid consists of a set of space flight missions, a robust research and analysis program designed to respond directly to the investigations, and technological development to enable the missions. As a recognition of the fact that it is extremely important to kindle and keep alive public excitement and participation in the Origins program, Education and Public Outreach (E/PO) is injected at all levels of the ASO plan. The ASO theme’s two highest priority missions in the near term (2003-2007 window) are:
In addition to their primary goals, NGST and TPF will carry out a broad range of other astrophysics investigations. Two notional missions are envisioned in the mid term (2008-2013).
Finally, in the long term (beyond 2013), ASO hopes to achieve its strategic goals through a spectroscopy mission to search for the "smoking gun" for evidence of life on other planets, and an imaging mission to obtain high resolution images of distant planets. The hallmark or the Origins Observatories is that each mission builds on scientific and technological foundations created by the prior missions and feeds forward science and technology to the follow-on missions. Thus, NGST builds on the legacy of HST scientifically in the areas of the origins and evolution of galaxies, structure and chemistry of the Universe, and the physics of stars and planet formation., and technologically in the areas of ultra-lightweight large optics, cryogenic deformable mirror, cryogenic actuator, detector technology, and precision deployable structure. Figure 2 summarizes enabling technologies between the missions currently under development, Space Interferometry Mission (SIM), Space Infrared Telescope Facility (SIRTF), ST-3, a technology development demonstration mission, the new starts, NGST and TPF, and the next generation missions. The ASO theme is working on a strategy to lay down the groundwork for achieving science goals for which we have no in hand technologies. In this spirit, the Large Telescopes Systems Initiative (LTSI) is proposed to address the next series of science grand challenges which require large telescopes to respond to the needs for very high sensitivity and resolution (spectral and spatial.) Four focus areas have been identified under LTSI.
In summary, LTSI will develop the breakthrough capabilities needed for UV to far-IR astrophysics by making telescopes an order of magnitude more lightweight than NGST using new materials, on-orbit deployment, and advanced micro-electronic mechanical (MEMS) devices for precision wavefront control. LTSI will develop the detectors and cooling needed to take full advantage of the low background space environment. LTSI is not about missions but about making possible the measurements that the community will need a decade from now to achieve important scientific goals. Astrobiology For completeness, it is worth mentioning that ASO is the "home" to astrobiology within OSS. Its goals are to understand the evolution of life on Earth so as to know how and where to search for life on other planets. Astrobiology objectives are:
These objectives have been translated into a series of investigations, which are currently being developed. Astrobiology is a major new initiative for NASA and promises cutting edge science which should help answer both of ASO’s defining questions. Summary The scientific community has laid out an extremely exciting and challenging roadmap for the ASO theme. A key component in achieving its scientific goals is the development of detectors in the wavelength range spanning from the UV to the infrared. The next step is to develop a research roadmap for detector development, so that ASO can achieve its long term science goals. Acknowledgements I would like to thank Anne Kinney, David Black, Charles Beichman, and Richard Capps for providing me the material presented in this talk. References Black, D.C., Kinney, A., Allamandola, L., Beichman, C., Bodenheimer, P., Cochran, W., Hammel, H., Johnston, K., McAlister, H., Neff, S.G., Ruden, S. P., Steidel, C. C., Stockman, H.S., 2000, Roadmap for the Office of Space Science Origins Theme (NASA, Pasadena: JPL) Origins web page http://origins.jpl.nasa.gov/ |