Tramonto sul mare: la rifrazione differenziale e la forma del Sole; Tramonto sul mare: la rifrazione differenziale e la forma del Sole
Differential refraction near the horizon is a parameter which has to be directly measured, since it depends on meteo conditions. A method for measuring it is presented, and two cases are discussed in detail: an observation without sea horizon available and a photo with sea horizon made by Aldo Bambini. The equation for differential refraction Yr=a·Y+b is given in this particular case (Y being the altitude of a solar point; a=0.8, b=6') and the effects of its variation with altitude are shown.
Astronomia. La rivista dell' Unione Astrofili Italiani
- Pub Date:
- June 2006
- Differential Refraction