This breathtaking visible-light image, taken with the Gemini South
telescope, looks as though it is ready to flutter off the screen. This
apparently wispy object is an outflow of gas known as the Chamaeleon
Infrared Nebula—so named because it is bright at some infrared wavelengths
of light, although it can also be seen in visible light, as in this view.
Hidden at the core of this reflection nebula, and at the center of this
image, is the engine of the nebula, a low-mass star (less massive than our
sun) that is eclipsed by a dark vertical band.
Even though it is concealed from view, this young, cool star emits streams
of fast-moving gas that have carved a tunnel through the interstellar cloud
from which the young star formed. Infrared and visible light emitted by the
star escapes along this tunnel and scatters off its walls, giving rise to
the wispy reflection nebula.
The bright red object to the right of the image center marks where some of
the fast-moving stream of gas lights up after colliding with slower-moving
gas in the nebula. It is known as a Herbig-Haro (HH) object and has the
designation HH 909A. Other Herbig-Haro objects have been found along the
axis of the star's outflow beyond the edges of the image to the right and
left.
Astronomers have suggested that the dark band at the center of the
Chamaeleon Infrared Nebula is a circumstellar disk—a reservoir of gas and
dust orbiting the star. Circumstellar disks are typically associated with
young stars and provide the materials needed to build planets. The reason
the disk appears as a band rather than a circle in this image is because it
is edge-on, only revealing one edge to observers here on Earth. Astronomers
believe that the nebula's central star is a young stellar object embedded
within the disk.
The background nebulosity, appearing in blue in this image, is reflecting
light from a nearby star located outside the frame.
The Chamaeleon Infrared Nebula resides within the larger Chamaeleon I dark
cloud, which is neighbored by the Chamaeleon II and Chamaeleon III dark
clouds. These three dark clouds collectively comprise the Chamaeleon
Complex, a large area of star formation that occupies almost the entirety of
the constellation Chamaeleon in the southern sky.
The detail in this image is thanks to the southern edition of the twin
Gemini Multi-Object Spectrographs (GMOS), located atop Cerro Pachón in Chile
at Gemini South, part of the international Gemini Observatory, a Program of
NSF's NOIRLab. GMOS has imaging capabilities in addition to being a
spectrograph, which makes it a versatile instrument.
"GMOS-South is the perfect instrument to make this observation, because of
its field of view, which can nicely capture the whole nebula, and because of
its ability to capture the emission from the nebula's ionized gas," said
NOIRLab instrument scientist German Gimeno.
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