- Horologium (constellation) (Wikipedia)
Horologium (Latin hōrologium, the pendulum clock, from Greek ὡρολόγιον, lit. ‘an instrument for telling the hour’) is a constellation of six stars faintly visible in the southern celestial hemisphere. It was first described by the French astronomer Nicolas-Louis de Lacaille in 1756 and visualized by him as a clock with a pendulum and a second hand. In 1922 the constellation was redefined by the International Astronomical Union (IAU) as a region of the celestial sphere containing Lacaille’s stars, and has since been an IAU designated constellation. Horologium’s associated region is wholly visible to observers south of 23°N.
- Star Tales - Horologium (ianridpath.com)
One of the small southern constellations introduced by the Frenchman Nicolas Louis de Lacaille after he mapped the southern stars in 1751–52. Lacaille wrote that the constellation represented a pendulum clock beating seconds, as used for timing his observations. Lacaille introduced it on his first chart in 1756 under the French name l’Horloge, but this was Latinized to Horologium on the second edition of 1763.
