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Optical Arrays For Future Astronomical Telescopes In Space

In a study being conducted for the NASA Marshall Space Flight Center Perkin-Elmer is evaluating several advanced optical space telescope concepts for achieving both higher sensitivity and higher angular resolution than the Hubble Space Telescope. These concepts include one-dimensional and two-dimensional coherent arrays of mirrors in both focal and afocal configurations. We will discuss some of the configurations that have been proposed for achieving a major advance in optical astronomy by means of arrays that might be launched and assembled in space about the year 2005. A fundamental trade-off concerns synthetic aperture concepts that provide very high angular resolution and designs that provide sensitivity for faint extended source imaging. We will review some of the advantages and disadvantages of several possible concepts with an emphasis on the technology development plans required to implement them.