Chamaeleon

Lore & Background

Chamaeleon was one of twelve constellations created by Petrus Plancius from the observations of Pieter Dirkszoon Keyser and Frederick de Houtman. It first appeared on a 35-cm diameter celestial globe published in 1597 (or 1598) in Amsterdam by Plancius and Jodocus Hondius. Johann Bayer 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.

Lacaille gave 17 stars Bayer designations Alpha through Pi in 1756, but omitted Omicron and Xi, and labelled two stars as Delta, Mu and Pi. In 1879, Benjamin Gould included Lambda Chamaeleontis and Pi2 Chamaeleontis as part of Musca and the designations were no longer used. There are four bright stars in Chamaeleon that form a compact diamond-shape approximately 10 degrees from the south celestial pole and about 15 degrees south of Acrux. Alpha Chamaeleontis is a white-hued star of magnitude 4.1, Beta Chamaeleontis is blue-white, Gamma Chamaeleontis is a red giant, and Delta Chamaeleontis is a wide double star.

In Chinese astronomy, the stars that form Chamaeleon were classified as the Little Dipper among the Southern Asterisms by Xu Guangqi. Chamaeleon is sometimes also called the Frying Pan in Australia.

Reader's Guide

Chamaeleon's significance lies in its role as one of the constellations created from early European exploration of the southern skies, first recorded on a celestial globe by Plancius and Hondius. Its four bright stars form a compact diamond shape near the south celestial pole, aiding navigation. The constellation contains the Eta Chamaeleontis cluster, a nearby young open cluster discovered in 1999, which is 8 million years old and lies 316 light-years from Earth. The Chamaeleon dark clouds are molecular clouds forming low-mass T Tauri stars, located 400 to 600 light-years away and containing tens of thousands of solar masses of gas and dust. The most prominent cluster of T Tauri stars and young B-type stars is in the Chamaeleon I cloud, associated with the reflection nebula IC 2631. Chamaeleon also hosts the planetary nebula NGC 3195, which appears in a telescope at about the same apparent size as Jupiter. Additionally, the constellation is the location of Cha 110913, a sub-brown dwarf or rogue planet with planets or moons, depending on classification. Its inclusion in Chinese astronomy as the Little Dipper and its Australian nickname of the Frying Pan reflect its cross-cultural recognition.

Did You Know?

• Chamaeleon was first defined at the end of the 16th century and appeared on a 35-cm celestial globe in 1597 (or 1598).
• The constellation contains a sub-brown dwarf or rogue planet called Cha 110913, which may have planets or moons.
• Chamaeleon is sometimes called the Frying Pan in Australia.