This NASA Hubble Space Telescope image captures one of three segments that comprise a 65-light-year wide star-forming region named the Chamaeleon Cloud Complex. The segment in this Hubble composite image, called Chamaeleon Cloud I (Cha I), reveals dusty-dark clouds where stars are forming, dazzling reflection nebulae glowing by the light of bright-blue young stars, and radiant knots called Herbig-Haro objects.
Herbig-Haro objects are bright clumps and arcs of interstellar gas shocked and energized by jets expelled from infant “protostars” in the process of forming. The white-orange cloud at the bottom of the image hosts one of these protostars at its center. Its brilliant white jets of hot gas are ejected in narrow torrents from the protostar’s poles, creating the Herbig-Haro object HH 909A.
The cross-like spikes around bright stars in the image occur when light waves from a very bright point source (like a star) bend around Hubble’s cross-shaped struts that support the telescope’s secondary mirror. As the light waves pass these struts, they coalesce on the other side, creating the bright, spikey starburst effect we see.
Hubble studied Cha I as part of a search for extremely dim, low-mass brown dwarfs. These “failed stars” lie somewhere in size between a large planet and a small star (10 to 90 times the mass of Jupiter), and do not have enough mass to ignite and sustain nuclear fusion in their cores. Hubble’s search found six new low-mass brown dwarf candidates that are helping astronomers better understand these objects.
This 315-million-pixel composite image is comprised of 23 observations made by Hubble’s Advanced Camera for Surveys. Gaps between those observations were filled by 20 Wide Field and Planetary Camera 2 images. Any remaining gaps were filled with ground-based data from ESO’s VISTA VIRCAM. To download the full high-resolution version of this image, visit Hubble Captures Chamaeleon Cloud I.