On Monday, April 28, 2014 7:50:06 PM UTC-4, haitic...@gmail.com wrote:   
   > Dear interested parties:   
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   > I saw this technical tidbit on seti.org. The name, Khayyam, is a famous name    
   in Persian history - The village of Khayyam is in the mountain in Northern    
   Iran. There is the source of underground tunnels which extend for hundreds of    
   miles. Omar Khayyam is famous for his Rubbaiyyat, and the poet Coleridge wrote   
    a poem about these tunnels. They used night sky IR cooling for climate    
   control.    
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   > I reproduce the Seti.org posting here:   
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   > Abstract: Sona Hosseini will report on progress toward development of a    
   tunable spatial heterodyne spectrometer (TSHS) at the fixed focus of the   
   Coudé    
   Auxiliary Telescope (CAT) in the Shane Telescope at Lick Observatory   
   (Khayyam).    
   Spatial Heterodyne Spectrometer (SHS) instruments are a class of    
   interferometric sensor capable of providing a combination of large étendue,    
   high resolving power (R=λ/dλ~ 105) and wide field of view (FOV~0.5 degree)   
   at    
   Optical and NUV wavelengths in a compact format.    
      
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   > The TSHS implementation addresses the bandpass limitation of the basic SHS    
   through controlled rotation of pilot mirrors in the interferometer. The use of   
    a single grating as both a dispersing and beam-splitting element in the all    
   reflective SHS greatly relaxes the precision required in the alignment of the    
   other optical elements relative to a more typical scanning Fourier Transform    
   Spectrometer and allows the TSHS implementation to be accomplished with low    
   cost commercial rotation stages. The new design builds on a previous design    
   originally tested in 2007, and will address several issues identified with the    
   input beam, output imaging, and grating efficiency. Here she will discuss the    
   design considerations going into this new system and the initial results of   
   the    
   installation and testing of the TSHS and the future plans.   
      
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   > Following completion of the ground based TSHS version (Khayyam), the longer   
   term goals of the TSHS project are to provide in flight testing on a sounding   
   rocket platform that Sona’s research group is developing and then ultimately   
   a translation to    
   satellite applications.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)