Abbreviation: Men    
Genitive: Mensae    
Pronunciation: /ˈmɛnsə/ genitive: /ˈmɛnsiː/    
Symbolism: the Table Mountain    
Right ascension: 4 ~ 7.5    
Declination: −71 ~ −85.5    
Family: La Caille    
Quadrant: SQ1    
Area: 153 sq. deg. (75th)    
Main stars: 4    
Bayer/Flamsteed stars: 16    
Stars with planets: 2    
Stars brighter than 3.00m: none    
Stars within 10.00 pc (32.62 ly): none    
Brightest star: α Men (5.09m)    
Nearest star: α Mensae (33.10 ly, 10.15 pc)    
Messier objects: none    
Meteor showers: none    
Bordering constellations: Chamaeleon Dorado Hydrus Octans Volans    
Visible at latitudes between +4° and −90°. Best visible at 21:00 (9 p.m.) during the month of January.    

Mensa is a constellation in the southern sky, created in the 18th century. Its name is Latin for table. It covers a keystone-shaped wedge of sky stretching from approximately 4h to 7.5h of right ascension, and −71 to −85.5 degrees of declination. Other than the south polar constellation of Octans, it is the most southerly of constellations. As a result, it is essentially unobservable from the Northern Hemisphere. Besides those already mentioned, its other neighbouring constellations are Chamaeleon, Dorado, Hydrus, and Volans. It is the only constellation named after a feature on Earth.

History
Mensa was created by Nicolas Louis de Lacaille out of dim Southern Hemisphere stars in honor of Table Mountain, a South African mountain. Although the stars of Mensa do not feature in any ancient mythology, the mountain it is named after has a rich mythology. Called "Tafelberg" in Dutch and German, the mesa has two neighboring mountains called "Devil's Peak" and "Lion's Head". Table Mountain features in the mythology of the Cape of Good Hope, notorious for its storms—the explorer Bartolomeu Dias saw the mesa as a mythical anvil for storms. Another myth relating to its dangers comes from Sinbad the Sailor, an Arabic folk hero who saw the mountain as a magnet pulling his ships to the bottom of the sea.

Notable features
Stars
Mensa contains no bright stars, with Alpha Mensae its brightest star at a barely visible magnitude 5.09, making it the faintest constellation in the entire sky. Alpha Mensae is a solar-type star (class G5 V) 33 light-years from Earth, and is considered a good prospect for harboring an Earth-like planet. Pi Mensae, on the other hand, while also solar-type (G1) and at 59 light-years, has been found to have a large gas giant in an eccentric orbit crossing the habitable zone, which would effectively rule out the existence of any habitable planets.

Deep-sky objects
Mensa contains part of the Large Magellanic Cloud (the rest being in Dorado).
The first images taken by the Chandra X-Ray Observatory were of PKS 0637-752, a quasar in Mensa with a large gas jet visible in both optical and x-ray wavelengths.

References
^ Staal 1988, p. 259.

Citations
Ridpath, Ian; Tirion, Wil (2007), Stars and Planets Guide, Princeton University Press, ISBN 978-0-691-13556-4 
Staal, Julius D.W. (1988), The New Patterns in the Sky: Myths and Legends of the Stars, The McDonald and Woodward Publishing Company, ISBN 0-939923-04-1 

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