Former constellations are old historical Western constellations that for various reasons are no longer widely recognised or are not officially recognised by the International Astronomical Union (IAU). [1] Prior to 1930, many of these defunct constellations were traditional in one or more countries or cultures. Some only lasted decades but others were referred to over many centuries. All are now recognised only for having classical or historical value. [2] Many former constellations had complex Latinised names after objects, people, or mythological or zoological creatures. [2] Others with unwieldy names were shortened for convenience. For example, Scutum Sobiescianum was reduced to Scutum, Mons Mensae to Mensa, and Apparatus Sculptoris to Sculptor.
Some of the Northern Sky's former constellations were placed in the less populated regions between the traditional brighter constellations just to fill gaps. In the Southern Sky, new constellations were often created from about the 15th century by voyagers who began journeying south of the Equator. European countries like England, France, the Netherlands, German or Italian states, etc., often supported and popularised their own constellation outlines. In some cases, different constellations occupied overlapping areas and included the same stars. These former constellations are often found in older books, star charts, or star catalogues.
The 88 modern constellation names and boundaries were standardised by Eugene Delporte for the IAU in 1930, under an international agreement, removing any possible astronomical ambiguities between astronomers from different countries. [3] Nearly all former or defunct constellations differ in their designated boundaries in as much as they have outlines that do not follow the exact lines of right ascension and declination. [4]
Argo Navis is the only constellation from Ptolemy's original list of 48 constellations that is no longer officially recognized. Due to its large size, it was split into three constellations by Nicolas Louis de Lacaille: Carina (the keel), Puppis (the poop deck), and Vela (the sails). [5] The new constellations were introduced in the 1763 star catalog Coelum Australe Stelliferum, which was published soon after de Lacaille's death.
Quadrans Muralis was originally created in 1795, placed in the northern skies between the still-accepted constellations Boötes and Draco. The Quadrantids meteor shower is named after this former constellation.
Argo Navis, or simply Argo, is one of Ptolemy's 48 constellations, now a grouping of three IAU constellations. It is formerly a single large constellation in the southern sky. The genitive is "Argus Navis", abbreviated "Arg". Flamsteed and other early modern astronomers called it Navis, genitive "Navis", abbreviated "Nav".
A Bayer designation is a stellar designation in which a specific star is identified by a Greek or Latin letter followed by the genitive form of its parent constellation's Latin name. The original list of Bayer designations contained 1,564 stars. The brighter stars were assigned their first systematic names by the German astronomer Johann Bayer in 1603, in his star atlas Uranometria. Bayer catalogued only a few stars too far south to be seen from Germany, but later astronomers supplemented Bayer's catalog with entries for southern constellations.
Canes Venatici is one of the 88 constellations designated by the International Astronomical Union (IAU). It is a small northern constellation that was created by Johannes Hevelius in the 17th century. Its name is Latin for 'hunting dogs', and the constellation is often depicted in illustrations as representing the dogs of Boötes the Herdsman, a neighboring constellation.
A Flamsteed designation is a combination of a number and constellation name that uniquely identifies most naked eye stars in the modern constellations visible from southern England. They are named for John Flamsteed who first used them while compiling his Historia Coelestis Britannica.
Abbé Nicolas-Louis de Lacaille, formerly sometimes spelled de la Caille, was a French astronomer and geodesist who named 14 out of the 88 constellations. From 1750 to 1754, he studied the sky at the Cape of Good Hope in present-day South Africa. Lacaille observed over 10,000 stars using a refracting telescope.
Octans is a faint constellation located in the deep Southern Sky. Its name is Latin for the eighth part of a circle, but it is named after the octant, a navigational instrument. Devised by French astronomer Nicolas Louis de Lacaille in 1752, Octans remains one of the 88 modern constellations. The southern celestial pole is located within the boundaries of Octans.
Pisces is a constellation of the zodiac. Its vast bulk – and main asterism viewed in most European cultures per Greco-Roman antiquity as a distant pair of fishes connected by one cord each that join at an apex – are in the Northern celestial hemisphere. Its old astronomical symbol is (♓︎). Its name is Latin for "fishes". It is between Aquarius, of similar size, to the southwest and Aries, which is smaller, to the east. The ecliptic and the celestial equator intersect within this constellation and in Virgo. The Sun passes directly overhead of the equator, on average, at approximately this point in the sky, at the March equinox.
Triangulum Australe is a small constellation in the far Southern Celestial Hemisphere. Its name is Latin for "the southern triangle", which distinguishes it from Triangulum in the northern sky and is derived from the acute, almost equilateral pattern of its three brightest stars. It was first depicted on a celestial globe as Triangulus Antarcticus by Petrus Plancius in 1589, and later with more accuracy and its current name by Johann Bayer in his 1603 Uranometria. The French explorer and astronomer Nicolas Louis de Lacaille charted and gave the brighter stars their Bayer designations in 1756.
Scutum is a small constellation. Its name is Latin for shield, and it was originally named Scutum Sobiescianum by Johannes Hevelius in 1684. Located just south of the celestial equator, its four brightest stars form a narrow diamond shape. It is one of the 88 IAU designated constellations defined in 1922.
Sculptor is a faint constellation in the southern sky. It represents a sculptor. It was introduced by Nicolas Louis de Lacaille in the 18th century. He originally named it Apparatus Sculptoris, but the name was later shortened.
Volans is a constellation in the southern sky. It represents a flying fish; its name is a shortened form of its original name, Piscis Volans. Volans was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman and it first appeared on a 35-cm (14") diameter celestial globe published in 1597 in Amsterdam by Plancius with Jodocus Hondius. The first depiction of this constellation in a celestial atlas was in Johann Bayer's Uranometria of 1603.
Lacerta is one of the 88 modern constellations defined by the International Astronomical Union. Its name is Latin for lizard. A small, faint constellation, it was defined in 1687 by the astronomer Johannes Hevelius. Its brightest stars form a "W" shape similar to that of Cassiopeia, and it is thus sometimes referred to as 'Little Cassiopeia'. It is located between Cygnus, Cassiopeia and Andromeda on the northern celestial sphere. The northern part lies on the Milky Way.
Columba is a faint constellation designated in the late sixteenth century, remaining in official use, with its rigid limits set in the 20th century. Its name is Latin for dove. It takes up 1.31% of the southern celestial hemisphere and is just south of Canis Major and Lepus.
Antinous is an obsolete constellation no longer in use by astronomers, having been merged into Aquila, which it bordered to the north.
Felis was a constellation created by French astronomer Jérôme Lalande in 1799. He chose the name partly because, as a cat lover, he felt sorry that there was not yet a cat among the constellations. It was between the constellations of Antlia and Hydra.
Taurus Poniatovii was a constellation created by the former rector of Vilnius University, Marcin Odlanicki Poczobutt, in 1777 to honor Stanislaus Poniatowski, King of Poland and Grand Duke of Lithuania. It consisted of stars that are today considered part of Ophiuchus and Aquila. It is no longer in use. It was wedged in between Ophiuchus, Aquila and Serpens Cauda. A depiction of the constellation can be found on the wall of the Vilnius University Astronomical Observatory.
Jordanus was a constellation introduced in 1612 on a globe by Petrus Plancius and first shown in print by Jakob Bartsch in his book Usus Astronomicus Planisphaerii Stellati (1624).
53 Eridani, also designated l Eridani, is a binary star in the constellation of Eridanus. The system has a combined apparent magnitude of 3.87. Parallax estimates made by the Hipparcos spacecraft put it at a distance of about 110 light-years, or 33.7 parsecs, from the Sun.
Urania's Mirror; or, a view of the Heavens is a set of 32 astronomical star chart cards, first published in November 1824. They are illustrations based on Alexander Jamieson's A Celestial Atlas, but the addition of holes punched in them allow them to be held up to a light to see a depiction of the constellation's stars. They were engraved by Sidney Hall, and were said to be designed by "a lady", but have since been identified as the work of the Reverend Richard Rouse Bloxam, an assistant master at Rugby School.