Chamaeleon () is a small

constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object. The first constellati ...

in the deep

southern sky The southern celestial hemisphere, also called the Southern Sky, is the southern half of the celestial sphere; that is, it lies south of the celestial equator. This arbitrary sphere, on which seemingly fixed stars form constellations, appears ...

. It is named after the

chameleon Chameleons or chamaeleons (Family (biology), family Chamaeleonidae) are a distinctive and highly specialized clade of Old World lizards with 200 species described as of June 2015. The members of this Family (biology), family are best known for ...

, a kind of

lizard Lizard is the common name used for all Squamata, squamate reptiles other than snakes (and to a lesser extent amphisbaenians), encompassing over 7,000 species, ranging across all continents except Antarctica, as well as most Island#Oceanic isla ...

. It was first defined in the 16th century.

History

Chamaeleon was one of twelve constellations created by

Petrus Plancius Petrus Plancius (; born Pieter Platevoet ; 1552 – 15 May 1622) was a Dutch- Flemish astronomer, cartographer and clergyman. Born, in Dranouter, now in Heuvelland, West Flanders, he studied theology in Germany and England. At the age of 24 ...

from the observations of

Pieter Dirkszoon Keyser Pieter Dirkszoon Keyser (occasionally Petrus Theodorus; – 11 September 1596) was a Dutch navigator and celestial cartographer who mapped several constellations on the southern celestial hemisphere. Voyages and star observation Little is ...

and

Frederick de Houtman Frederick de Houtman ( – 21 October 1627) was a Dutch explorer, navigator, and colonial governor who sailed on the first Dutch expedition to the East Indies from 1595 until 1597, during which time he made observations of the southern cel ...

. It first appeared on a 35-cm diameter celestial globe published in 1597 (or 1598) in

Amsterdam Amsterdam ( , ; ; ) is the capital of the Netherlands, capital and Municipalities of the Netherlands, largest city of the Kingdom of the Netherlands. It has a population of 933,680 in June 2024 within the city proper, 1,457,018 in the City Re ...

by Plancius and

Jodocus Hondius Jodocus Hondius (Latinized version of his Dutch name: ''Joost de Hondt'') (17 October 1563 – 12 February 1612) was a Flemish and Dutch engraver and cartographer. He is sometimes called Jodocus Hondius the Elder to distinguish him from h ...

Johann Bayer Johann Bayer (; 1572 – 7 March 1625) was a German lawyer and uranographer (celestial cartographer). He was born in Rain in 1572. In 1592, aged 20, he began his study of philosophy and law at the University of Ingolstadt, after which he ...

was the first uranographer to put Chamaeleon in a celestial atlas. It was one of many constellations created by European explorers in the 15th and 16th centuries out of unfamiliar Southern Hemisphere stars.

Features

Stars

There are four bright stars in Chamaeleon that form a compact diamond-shape approximately 10 degrees from the

south celestial pole The north and south celestial poles are the two points in the sky where Earth's axis of rotation, indefinitely extended, intersects the celestial sphere. The north and south celestial poles appear permanently directly overhead to observers at ...

and about 15 degrees south of Acrux, along the axis formed by Acrux and

Gamma Crucis Gacrux is the third-brightest star in the southern constellation of Crux, the Southern Cross. It has the Bayer designation Gamma Crucis, which is Latinised from γ Crucis and abbreviated Gamma Cru or γ Cru. With an apparent visual magn ...

. Alpha Chamaeleontis is a white-hued star of magnitude 4.1, 63 light-years from Earth.

Beta Chamaeleontis Beta Chamaeleontis, Latinized from β Chamaeleontis, is the third-brightest star in the southern constellation A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy) ...

is a blue-white hued star of magnitude 4.2, 271 light-years from Earth. Gamma Chamaeleontis is a red-hued giant star of magnitude 4.1, 413 light-years from Earth. The other bright star in Chamaeleon is Delta Chamaeleontis, a wide

double star In observational astronomy, a double star or visual double is a pair of stars that appear close to each other as viewed from Earth, especially with the aid of optical telescopes. This occurs because the pair either forms a binary star (i.e. a ...

. The brighter star is Delta² Chamaeleontis, a blue-hued star of magnitude 4.4. Delta¹ Chamaeleontis, the dimmer component, is an orange-hued giant star of magnitude 5.5. They both lie about 350 light years away. Chamaeleon is also the location of Cha 110913, a unique dwarf star or proto solar system.

Deep-sky objects

In 1999, a nearby

open cluster An open cluster is a type of star cluster made of tens to a few thousand stars that were formed from the same giant molecular cloud and have roughly the same age. More than 1,100 open clusters have been discovered within the Milky Way galaxy, and ...

was discovered centered on the star η Chamaeleontis. The cluster, known as either the

Eta Chamaeleontis cluster Eta Chamaeleontis, Latinisation of names, Latinized from η Chamaeleontis, is a star in the constellation Chamaeleon. It has an apparent magnitude of about 5.5, meaning that it is just barely visible to the naked eye. Based upon parallax ...

or Mamajek 1, is 8 million years old, and lies 316

light years A light-year, alternatively spelled light year (ly or lyr), is a unit of length used to express astronomical distances and is equal to exactly , which is approximately 9.46 trillion km or 5.88 trillion mi. As defined by the International Astro ...

from Earth. The constellation contains a number of

molecular clouds A molecular cloud—sometimes called a stellar nursery if star formation is occurring within—is a type of interstellar cloud of which the density and size permit absorption nebulae, the formation of molecules (most commonly molecular hydrogen, ...

(the Chamaeleon dark clouds) that are forming low-mass

T Tauri star T Tauri stars (TTS) are a class of variable stars that are less than about ten million years old. This class is named after the prototype, T Tauri, a young star in the Taurus Molecular Cloud, Taurus star-forming region. They are found near mo ...

s. The cloud complex lies some 400 to 600

from Earth, and contains tens of thousands of solar masses of gas and dust. The most prominent cluster of T Tauri stars and young B-type stars are in the Chamaeleon I cloud, and are associated with the reflection nebula IC 2631. Chamaeleon contains one planetary nebula, NGC 3195, which is fairly faint. It appears in a telescope at about the same apparent size as

Jupiter Jupiter is the fifth planet from the Sun and the List of Solar System objects by size, largest in the Solar System. It is a gas giant with a Jupiter mass, mass more than 2.5 times that of all the other planets in the Solar System combined a ...

Equivalents

Chinese astronomy Astronomy in China has a long history stretching from the Shang dynasty, being refined over a period of more than 3,000 years. The Ancient China, ancient Chinese people have identified stars from 1300 BCE, as Chinese star names later categori ...

, the stars that form Chamaeleon were classified as the

Little Dipper Ursa Minor (, contrasting with Ursa Major), also known as the Little Bear, is a constellation located in the far northern sky. As with the Great Bear, the tail of the Little Bear may also be seen as the handle of a ladle, hence the North Amer ...

() among the Southern Asterisms () by

Xu Guangqi Xu Guangqi or Hsü Kuang-ch'i (April 24, 1562– November 8, 1633), also known by his baptismal name Paul or Paul Siu, was a Chinese agronomist, astronomer, mathematician, scholar-bureaucrat, politician, and writer during the late Ming dynasty ...

. Chamaeleon is sometimes also called the Frying Pan in Australia.

Citations

References

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External links

The Deep Photographic Guide to the Constellations: Chamaeleon

"The eta Chamaeleontis Cluster: A Remarkable New Nearby Young Open Cluster" (Mamajek, Lawson, & Feigelson 1999)

"WEBDA open cluster database entry for Mamajek 1"

NGC 3620 Barred spiral galaxy
{{DEFAULTSORT:Chamaeleon Southern constellations Constellations listed by Petrus Plancius