|MadSci Network: Physics|
Schmidt-cassegrain telescope. Corrector plate collects dew under certain conditions. I read the posted article re dew. Corrector plate radiates to 3 degree Kelvin sky. Air molecules contribute air temperature heating to outside of corrector plate. Inside telescope, walls of telescope conduct heat from outside, warming the air molecules which transfer heat by conduction to the inside of the corrector plate. Air inside also presumably radiates heat through the corrector plate. Assuming thin steel telescope walls 25 inches in length and a corrector plate thickness of 3/8 inch and diameter 10 inches, it should be possible to calculate the surface temperature of the outside of the corrector plate using the heat equation, the thermal conductivity of steel (.115), air (.0000568), glass (.002) and the air temperature. (Does the radiative efficiency of glass also play a part?) The dew point can then be used to determine approximately when dew will start forming. (I think if my old college professors had thought of this, it would have been on one of my tests. It is only at this time of year that this begins to be a problem for me here in Arizona... See my web site http://www.astroshow.com and you will see why it matters to me.)
Re: How can I predict when dew will form on a corrector plate.
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