| Popis: |
Seeing is generally caused by non-homogeneous variations in the refractive index of the column of air in the observed light path. The refractive index is affected by wavelength, air pressure, temperature and relative humidity. In this paper the Cauchy-Lorenz formula for the refractive index of air is evaluated to find the relative dependence of seeing on each of these parameters. A standard atmospheric model is used to evaluate the effect of altitude on each term, and from this an expression for the variation of seeing as a function of altitude is derived. |
