Tucana

Tucana is a constellation of stars in the southern sky, named after the toucan, a South American bird. It is bordered by Hydrus to the east, Grus and Phoenix to the north, Indus to the west and Octans to the south. The constellation contains 47 Tucanae, one of the brightest globular clusters in the sky, and most of the Small Magellanic Cloud. It ranks 48th of the 88 constellation in size.

About Tucana in brief

Tucana is a constellation of stars in the southern sky, named after the toucan, a South American bird. It is one of twelve constellations conceived in the late sixteenth century by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman. Tucana is bordered by Hydrus to the east, Grus and Phoenix to the north, Indus to the west and Octans to the south. The constellation contains 47 Tucanae, one of the brightest globular clusters in the sky, and most of the Small Magellanic Cloud. The recommended three-letter abbreviation for the constellation, as adopted by the International Astronomical Union in 1922, is “Tuc”. The official constellation boundaries, as set by Belgian astronomer Eugène Delporte in 1930, are defined by a polygon of 10 segments. Within the constellation’s boundaries are around 80 stars brighter than an apparent magnitude of 2.2. Five star systems have been found to have exoplanets to date. The brightest star in the constellation is Alpha Tucanai, with an apparent visual magnitude of 87.3. It remains below the horizon at latitudes north of the 30th parallel in the Northern Hemisphere, and is circumpolar at latitude south of the 50th Parallel in the Southern Hemisphere.

French explorer and astronomer Nicolas Louis de Lacaille gave its stars Bayer designations in 1756. In 1879, American astronomer Benjamin Gould labelled a pair of stars close together as Lambda Tucana and a group of three stars Beta Tucana, now known as the globular cluster Mu. The layout of the stars of the constellation has been likened to a kite, with Tucana’s brightest star Alpha being brighter in the middle than Mu’s Alpha. It ranks 48th of the 88 constellation in size. It was first appeared on a 35-centimetre-diameter celestial globe published in 1598 in Amsterdam by Plancius with Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in the German cartographer Johann Bayer’s Uranometria of 1603. Although he depicted Tucana on his chart, Bayer did not assign its starsayer designations. It has been named after a particular bird with a long beak, a hornbill, a bird native to the East Indies, by Johannes Kepler and Giovanni Battista Riccioli, and Caesius as Pica Indica. In English, it was interpreted on Chinese charts as Niǎohuì “bird’s beak”, and in England as “Brasilian Pye”, while Johannes Kepler termed it Anser Americanus American Goose and Caesius as Pica Indica.