07 Dec 2025
The Chamaeleon molecular cloud complex occupies most of the eastern and central regions of the homonymous constellation, spreading also in the neighboring Apus, Musca, Carina and Octans. Deep, widefield images show the entre region swathed in smeary palls of interstellar dust. It is one of the nearest star-forming regions at a distance of 500-600 light-years. The complex comprises 3 molecular subgroups – Cha I, II and III.
Infrared observations have revealed each cloud has a different star formation history and structure, even though they are all physically related. Cha I has established stars and appears to have arrived at the end of its main star-formation phase. Cha II is actively forming stars and has a more fragmented appearance. Cha III (showed in the picture) appears quiet and shows no clear signs of star formation.
The differences in evolution resides in the different exposure to the Scorpius-Centaurus OB association, a site of many supernovae. Also, the matter distribution played a significant role. Magnetic lines add to the differences in star formation, by shaping the cloud structure.
Cha I
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