The use of graphite fiber composites to fabricate mirrors and telescope structures promises to make available, in the near term, a versatile and cost-effective tool for optical astronomy, including the economical fabrication and operation of telescopes ranging from small (~1m) aperture for education and research to extremely large (30m+) segmented telescopes (ELTs) for cutting-edge research. The focus of this proposal is a three-year program to develop, test, and decisively demonstrate the astronomical capabilities of this technology. The project, known as ULTRA (Ultra-Lightweight Telescope for Research in Astronomy), draws upon the resources of private industry (Composite Mirror Applications, Inc. – CMA, Inc., Astronomical Research Cameras, Inc.- ARC, Inc.) and five academic departments at four institutions of higher education (University of Kansas - Aerospace Engineering and Physics & Astronomy, Dartmouth Astronomy, San Diego State University Astronomy, Physics and Computer Science, Emporia State University).

This project intends to demonstrate to the astronomical community that a viable alternative exists to traditional glass-mirror technology. We will design, test, build, and operate a 1m-class, research telescope at Mt. Laguna Observatory (MLO), a dark, remote observing site with well-developed infrastructure, located 50 miles east of San Diego. It is structured in three phases:

1) CMA, Inc., in collaboration with the Aerospace Engineering team at KU, will build and test the structural characteristics of several mirror types and at least two optical tube assemblies (OTA). Finite-element analyses of the structures will be performed at KU, allowing computer simulations of the optimal design for the support assembly. Wind tunnel testing will be performed at KU to assess the aerodynamic loading experienced by the telescope assembly during normal operating conditions. Based upon these test results, two scale-model telescopes with 0.4 m mirrors will be built. One, a working telescope, will be equipped with a CCD camera and attached to the 2.4 m telescope at MDM Observatory on Kitt Peak in Arizona. The optical image quality of the prototype will be tested by direct simultaneous comparison of its images to those obtained with the 2.4 m telescope. The second model will undergo further wind tunnel tests, as well as detailed stress analyses and quantification of the torsional and vibrational modes of the optics and the OTA, at the KU Engineering facility. Finite-element analyses will be revised, refined, and used to improve the final design of a 1.0 m-Cassegrain telescope.

2) Manufacture of the 1.0 m-telescope optics and OTA will occur while the 0.4 m-telescope mount and dome at MLO are renovated. The telescope instrumentation, an ARC, Inc. CCD imaging camera, will be constructed and the pieces integrated into a working telescope and dome, remotely operated over the Internet, by the end of the second year. Prior to installation at MLO, the mirror will be independently tested and characterized by an optical lab in Tucson.

3) The telescope will be tested at MLO in operational mode for the third year, with the primary focus on repeated imaging of the same fields of clusters, nebulae, and galaxies, as well as reproducing projects completed on 0.9 -1.0 m telescopes of traditional technology. When combined with independent seeing measurements made with a dedicated differential image motion monitor at MLO, a comparison of the quality and stability of the ULTRA optics will be made. The mirror will be removed after one year and independently retested by the same optical lab for comparison to the condition prior to installation.

The broader impact of the technology includes greater access to affordable, state-of-the-art telescopes for educational and public institutions at all levels. In addition to aiding the research programs of KU and SDSU astronomers, the completed telescope will be (a) a research tool available to all qualified observers within the state of Kansas, (b) accessible to the community colleges in the SDSU area for both research and education, (c) incorporated into the teaching mission for undergraduate and Master’s degree students at both institutions, and (d) used for public education by promoting the new technology and the science both on-site at Mt. Laguna and via Web access to observers and to observations in progress.