Solar Calculations, Ecliptic
Daniel Perez Astudillo May 15, 2026From time to time, some of the planets in our solar system appear close in our sky. On the 20th of June, 2015, for example, the Moon, Venus and Jupiter had a close encounter, as seen from Earth, around sunset.
Fig.1: The Moon, Jupiter and Venus at 6:58 pm (Doha time) on 20/Jun/2015.
Fig.2: Simulated view, with ecliptic shown. Made with Stellarium (https://stellarium.org/).
Astronomical calculations allow us to know the position of the Sun in the sky of any observer on Earth at any time of the year; in other words, we can track the Sun, the fuel of solar technologies. Knowing the Suns position is fundamental for most solar data quality checks done on measurements of solar radiation, and tracking the Sun is essential to take some of those measurements, as well as for some solar energy conversion technologies.