A stunning new image captured by the Dark Energy Camera (DECam) reveals the Circinus West molecular cloud, a dense, dark region where young stars are actively forming. Located about 2,500 light-years away, this vast stellar nursery stretches 180 light-years across and contains gas and dust amounting to 250,000 times the mass of the Sun.
Cosmic Gems in Circinus West. Some of the interesting features found in the celestial shadow known as the Circinus West molecular cloud. This image was taken with the Department of Energy-fabricated 570-megapixel Dark Energy Camera (DECam) — one of the most powerful digital cameras in the world. Within this stellar nursery's opaque boundaries, infant stars ignite from cold, dense gas and dust, while outflows hurtle leftover material into space. DECam is mounted on the U.S. National Science Foundation Víctor M. Blanco 4-meter telescope at Cerro Tololo Inter-American Observatory in Chile, a Program of NSF NOIRLab. Image Credit: CTIO/NOIRLab/DOE/NSF/AURA. Image Processing: T.A. Rector (University of Alaska Anchorage/NSF NOIRLab), D. de Martin & M. Kosari (NSF NOIRLab)
The Circinus West molecular cloud, which is known for its abundance of newly formed stars and is rich in gas and dust, is this winding, shadowy structure that is emphasized by a densely packed starry background.
The cradles of star formation are interstellar clouds known as “molecular clouds,” which are so cold and dense that atoms there form molecules through bonding. They are known as dark nebulae because some, like Circinus West, are so dense that light cannot pass through, giving them a mottled, dark appearance.
Astronomers have gained a great deal of knowledge about the mechanisms underlying star formation and the evolution of molecular clouds, thanks to the cloud's thriving population of young stars.
The Dark Energy Camera (DECam), developed by the Department of Energy, was used to take this picture. It was installed on the Víctor M. Blanco 4-meter telescope at the Cerro Tololo Inter-American Observatory in Chile, which is a program of NSF NOIRLab.
It displays the western part of the larger Circinus molecular cloud, a striking celestial object in the constellation Circinus that is roughly 2500 light-years away from Earth. It has a mass 250,000 times that of the Sun and is 180 light-years across.
Numerous young stellar objects, or stars that are still developing, are known to exist in Circinus West. These young stars stand out despite being covered in a thick layer of gas and dust. Zooming in reveals different hints of their presence scattered throughout the snaking tendrils of Circinus West.
The faint patches of light that can be seen bursting through the hazy clouds are one sign of recently formed stars. Molecular outflows, powerful jets launched by protostars to shed excess gas and momentum gathered during their formation, have sculpted the cavities around the actively forming stars that are emitting this light.
These energetic outflows are a powerful tool for studying stellar nurseries and are far easier for astronomers to locate than the embedded stars themselves.
Many of the bright spots scattered throughout the dark clouds mark the locations of young stars that have expelled the material once surrounding them. Circinus West's central black plume, or the Cir-MMS region, which roughly resembles a downward-stretched hand with long, shadowy fingers, contains multiple outflow sources.
A cavity is being carved out of the opaque cloud near the center of this region by the radiation from a newborn star. And with a burst of light at the very bottom left of the main cloud, another declares its birth.
The existence of Herbig-Haro (HH) objects is another indication of star formation, and Circinus West is full of them. HH objects are luminous red nebulosity patches that are frequently located close to young stars.
They are created when fast-moving gas expelled by stars collides with slower-moving gas in the interstellar medium or surrounding molecular cloud. Numerous HH objects can be seen when visually scanning Circinus West. Three newly found HH objects are visible, fluttering across the face of the dark clouds to the left of Cir-MMS.
In addition to providing important hints about the star formation process, examining the outflows in Circinus West may also show how young stars affect their surroundings. Because of its wide range of outflows, it provides an ideal environment for researching not only star life cycles but also molecular cloud dynamics and the processes that control galaxy evolution. We may be able to learn more about the processes that led to the emergence of the Universe from the massive outflows that are taking place there, which may even resemble the conditions under which the Solar System formed.