All 88 Constellations: 38 Were Added After 1500

Ptolemy's 48, and the 50 that descend from them

Ptolemy's star catalogue fills books 7 and 8 of the Almagest. In the Greek text edited by J. L. Heiberg it runs through 48 constellation headings: 21 northern, 12 along the zodiac and 15 southern. Its closing tally gives 1,022 stars in all. Counting Argo's three later parts, Ptolemy's 48 make 50 of today's 88.

The exception to a one-to-one match is Argo, the ship. Lacaille lettered its stars in three parts, the keel, the stern and the sails, and the IAU list keeps them as Carina, Puppis and Vela. English Wikipedia's Argo Navis article dates that split to Lacaille's "1755 catalogue" in its opening and to his catalogue of 1763 further down. Wikipedia's table of the 88 gives 1756.

Ptolemy also listed stars outside any figure. Among the "unformed" stars around Leo he records "νεφελοειδοῦς συστροφῆς καλουμένου Πλοκάμου," "a cloudy cluster called the Lock" (Translation: Where Tales Began), in Almagest 7.5. The Latin De Astronomia credited to Hyginus says that Conon of Samos and Callimachus took those stars to be Queen Berenice's hair, which she had vowed to cut off if her husband came home victorious (book 2, chapter 24).

As one of today's constellations, the Lock is younger. English Wikipedia credits Caspar Vopel's celestial globe of 1536 with making it one, and also credits Tycho Brahe, who catalogued it in 1602. The same article notes that the ancient astronomers Hipparchus and Geminus had already recognized it as a distinct constellation.

The 88 at a glance

The timeline below places Ptolemy's 48 at about AD 150 and each later constellation at the year a globe or map maker first showed it, in the sources checked. Where those sources give two years, the square sits at the later one. Each year comes from the source named in its row of the index, following how this site dates a record.

The names come from two kinds of source. The IAU's page describes its list as a mix of the ancient Greek patterns recorded by Ptolemy and patterns added later by astronomers. The table gives each newer constellation's mapmaker, from Vopel in 1536 to Lacaille in 1756. In 1922 the IAU fixed one Latin name and one abbreviation for every entry.

Table data: 88-constellations-index.csv Data source on record: IAU constellation names, abbreviations and English names (The Constellations, read 2026-10-18), IAU, CC BY 4.0, https://iauarchive.eso.org/public/themes/constellations/, with each row's source and link, plus the Aratus line, Ovid passage and Hyginus chapter behind the matrix further down.

Navigators' stars and Bayer's 1603 atlas

Twelve of the 38 later constellations are credited to a trading voyage. Pieter Dirkszoon Keyser was chief navigator on the first Dutch voyage to the East Indies, which left Texel on April 2, 1595. According to E. B. Knobel's 1917 study of the southern constellations, the cartographer Petrus Plancius had taught him mathematics and astronomy. English Wikipedia adds that Plancius asked him to map the southern sky.

Keyser probably made most of his observations at Madagascar, where the fleet stopped from September 1595, English Wikipedia says. He died in 1596. Wikipedia names Frederick de Houtman among his helpers, but Knobel, calling his evidence circumstantial, credited the twelve new constellations to Keyser alone. Wikipedia says Plancius put them on a globe published by Jodocus Hondius in late 1597, and its table of the 88 gives 1598.

Writing in 1917, Knobel gave three works of 1603 as the earliest publications of them: Johann Bayer's atlas Uranometria, de Houtman's star catalogue and a globe by Willem Blaeu. Bayer printed all twelve on one plate and credited them to "Petrus Theodori," a Latin form of Keyser's name, and he is often wrongly credited with them, English Wikipedia notes. Most are named after animals that 16th-century explorers had encountered, among them the bird of paradise (Apus), the toucan (Tucana), the flying fish (Volans) and the chameleon.

According to Knobel, one of the twelve, Triangulum Australe, was already on a world map that Plancius made in 1594, before the fleet sailed. Knobel could not trace where it came from.

Plancius added more of his own. As English Wikipedia summarizes it, he drew Columba, which he called Noah's Dove, on a wall map of 1592. He put Camelopardalis (the giraffe) and Monoceros (the unicorn) on a globe of 1612 or 1613.

Crux, the Southern Cross, is the knottiest row. Navigators described it before the mapmakers did: Knobel cites Antonio Pigafetta on Magellan's voyage of 1519 and a sketch by Andrea Corsali, in a letter that Knobel dates to 1517 and English Wikipedia to 1516. Wikipedia's Crux article says a globe by Emery Molyneux and a map by Plancius showed it in 1592, in the wrong place, and that globes by Plancius and Hondius placed it correctly in 1598 and 1600. Wikipedia's table of the 88 gives 1589 instead.

Hevelius adds seven, 1690

Johannes Hevelius, an astronomer and city councillor in Danzig (Gdańsk), described ten new constellations, of which seven are still in use. His star atlas Firmamentum Sobiescianum appeared around 1690, three years after his death in 1687, and English Wikipedia credits his widow, Elisabeth, with publishing two of his works posthumously. The seven are Canes Venatici (the hunting dogs), Lacerta (the lizard), Leo Minor, Lynx, Scutum, Sextans and Vulpecula (the fox).

The IAU's history notes that astronomers were free to invent figures between the existing ones, often to flatter a patron or a monarch. According to English Wikipedia, Hevelius named Scutum Scutum Sobiescianum, Sobieski's Shield, to mark King John III Sobieski's victory at the Battle of Vienna in 1683. Sextans recalls the sextant he lost when fire destroyed his observatory on September 26, 1679.

Lacaille's fourteen: instruments and a mountain

Nicolas-Louis de Lacaille studied the southern sky from the Cape of Good Hope between 1750 and 1754. A planisphere of the southern sky dated 1756 already shows several of his new figures, under French names such as "Octans de Reflexion," "Montagne de la Table" and "Reticule Romboide." His full catalogue, Coelum Australe Stelliferum, came out in 1763. That was the year after his death.

Thirteen of the fourteen take their names from instruments and tools. Their English names in the IAU's list include the Air Pump, the Furnace, the Clock, the Microscope, the Octant and the Telescope. English Wikipedia's table records that Sculptor began as Apparatus Sculptoris, the sculptor's tools. The fourteenth, Mensa, is named for Table Mountain at the Cape, which English Wikipedia calls the only constellation named after a feature on Earth.

Illustration

The map below shades Lacaille's fourteen on the IAU borders around the south celestial pole. Pyxis, the compass, lies near what was once counted as part of Argo's mast, as English Wikipedia's Argo Navis article notes, yet Lacaille treated it as a separate instrument.

Where the myths are written

Not every constellation has a myth in the three classical sources checked for this page. By this page's count, 50 of today's 88 appear in at least one of them and 38 in none. The 38 are Equuleus, the little horse that Ptolemy lists, and every post-1500 addition except Coma Berenices.

The oldest of the texts checked is the Phaenomena of Aratus, a Greek poem from the third century BC. The poem puts a lost work by Eudoxus into verse. It describes 47 of Ptolemy's 48, all except Equuleus, and it gives the stars of the Southern Crown as a ring without a name (lines 400–401). Aratus is frank about the kneeling figure.

τὸ μὲν οὔτις ἐπίσταται ἀμφαδὸν εἰπεῖν, οὐδʼ ὅτινι κρέμαται κεῖνος πόνῳ, ἀλλά μιν αὕτως Ἐγγόνασιν καλέουσι. (Aratus, Phaenomena 64–66, Greek text ed. G. R. Mair, 1921)

No one knows how to say plainly what it is, or at what labor he toils; they simply call him the Kneeler. (Translation: Where Tales Began)

The Latin De Astronomia credited to Hyginus covers 47 of the 48 in 41 chapters, some shared by two or three figures, and it tucks Berenice's hair into the chapter on Leo. Its date is uncertain. English Wikipedia places it probably in the reign of Augustus, while noting that its star lists follow Ptolemy's order, which supports the idea of a second-century compilation.

Ovid's Fasti, a poem on the Roman calendar made public in AD 8, names many of Ptolemy's figures as stars. With his Metamorphoses, it names 28 of the 48 by this page's count, plus Capella, the goat star in Auriga.

Perseus, Andromeda, Cepheus and Cassiope all appear in book 4 of the Metamorphoses, but not as stars. The matrix leaves out the Greek star-myth collection known as the Catasterismi, as no edition of it was read for this page. Cassiopeia is one of Aratus's 47 (line 189) with her own chapter in Hyginus (2.10); the Cassiopeia entry follows her further.

How the list and the borders became official

By the 19th century more than a hundred constellations could be found on star charts, the IAU's history notes, because nothing stopped astronomers from inventing new ones. At its first General Assembly, in Rome in 1922, the IAU's Commission on Notations and Units agreed on a list of 88. The list covers the whole sky, and each name has a three-letter abbreviation.

At the 1925 General Assembly in Cambridge, England, Eugène Delporte of the Royal Observatory in Brussels proposed a set of borders. They ran along lines of right ascension and declination, the sky's longitude and latitude. The IAU asked him to keep every known variable star in the constellation it already belonged to, which produced some awkward outlines. His boundaries were approved at Leiden in 1928 and published in 1930 in Délimitation scientifique des constellations, with an Atlas céleste.

Since then, a star or galaxy is "in" a constellation when it lies inside those borders, whatever figure is drawn around it. Where Tales Began treats the borders as a modern administrative survey, approved at a General Assembly in 1928, not as a legacy of the myths.