- A small, faint constellation of the far southern sky invented by the French astronomer Nicolas Louis de Lacaille to commemorate Table Mountain near Cape Town, South Africa, from where he catalogued the southern stars in 1751–52. Lacaille originally gave it the French name Montagne de la Table on the first version of his planisphere published in 1756 but this was Latinized to Mons Mensae on the second edition of 1763. In 1844 the English astronomer John Herschel proposed shortening it to Mensa. Francis Baily adopted this suggestion in his British Association Catalogue of 1845, and it has been known as Mensa ever since.
- Beta Ophiuchi (Wikipedia)
Beta Ophiuchi or β Ophiuchi, also named Cebalrai /ˌsɛbəlˈreɪ.iː/, is a star in the equatorial constellation of Ophiuchus. The apparent visual magnitude of this star is 2.7, which is readily visible to the naked eye even from urban skies. The distance to this star can be estimated using parallax measurements, yielding a value of 83.4 light-years (25.6 parsecs) from the Sun.