Horologium is a constellation of six faintly visible stars 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. The boundaries of Horologium (literally 'an instrument for telling the hour') were specified in 1922 by the International Astronomical Union, and it has since been one of their designated constellations. All parts of the constellation are visible to observers south of 23°N. The constellation's brightest star – and the only one brighter than an apparent magnitude of 4 – is Alpha Horologii (at 3.85), an ageing orange giant star that has swollen to around 11 times the diameter of the Sun. The long-period variable-brightness star, R Horologii (4.7 to 14.3), has one of the largest variations in brightness known for stars in the night sky visible to the unaided eye. Four star systems in the constellation are known to have exoplanets; one – Gliese 1061 – contains an exoplanet in its habitable zone.
Read more: <https://en.wikipedia.org/wiki/Horologium_%28constellation%29> _______________________________ Today's selected anniversaries: 1802: English poet William Wordsworth and his sister Dorothy encountered a "long belt" of daffodils while walking around Ullswater in the Lake District, inspiring him to pen his best-known work, "I Wandered Lonely as a Cloud". <https://en.wikipedia.org/wiki/I_Wandered_Lonely_as_a_Cloud> 1994: At a GATT ministerial meeting in Marrakesh, Morocco, representatives of 123 countries and the European Communities signed an agreement to establish the World Trade Organization. <https://en.wikipedia.org/wiki/World_Trade_Organization> 2019: A fire severely damaged the Notre-Dame de Paris cathedral, destroying the building's timber spire and much of its roof. <https://en.wikipedia.org/wiki/Notre-Dame_de_Paris_fire> _____________________________ Wiktionary's word of the day: mummy brown: 1. (painting, historical) A brown pigment originally prepared from the ground-up remains of Egyptian animal or human mummies mixed with bitumen, etc. 2. The colour of this pigment, a variable brown intermediate between raw umber and burnt umber. mummy brown colour: <https://en.wiktionary.org/wiki/mummy_brown> ___________________________ Wikiquote quote of the day: Doubt comes in at the window, when Inquiry is denied at the door. --Benjamin Jowett <https://en.wikiquote.org/wiki/Benjamin_Jowett> _______________________________________________ Wikipedia Daily Article mailing list. To unsubscribe, visit: https://lists.wikimedia.org/mailman/listinfo/daily-article-l Questions or comments? Contact [email protected]
