1–3 Jul 2026
Astronomical Observatory, Cluj-Napoca, Romania
Europe/Bucharest timezone

Aspects of celestial mechanics pertinent to sundial construction

Not scheduled
20m
Astronomical Observatory, Cluj-Napoca, Romania

Astronomical Observatory, Cluj-Napoca, Romania

Ciresilor 19 Street, Cluj-Napoca, Cluj
Poster

Speaker

Dr Iharka Csillik (Romanian Academy. Astronomical Institute. Cluj-Napoca Astronomical Observatory)

Description

The construction of a sundial represents a practical application of celestial mechanics, converting the perceived movement of the Sun into a measurement of local time. The precision of a sundial is contingent upon a comprehensive understanding of the Earth's rotation, the tilt of its axis, and the principles of its orbital mechanics. For example, the equation of time is derived from two primary factors: the eccentricity of Earth's orbit, as described by Kepler's second law, and the obliquity of the ecliptic, which refers to the tilt of the Earth. This equation quantifies the discrepancy in minutes that must be accounted for to synchronize the time shown by a sundial with standard clock time. The objective of this research is to present alternative approximations for straightforward yet precise equations, along with practical implementations illustrated through specific models of sundials.

Authors

Dr Iharka Csillik (Romanian Academy. Astronomical Institute. Cluj-Napoca Astronomical Observatory) Tamás Schefler (Babeș-Bolyai University)

Presentation materials

There are no materials yet.