via Wired: Wired Science by Lisa
Grossman on 6/30/10

This wispy blue cloud of gas and dust is a star-forming region surrounding
the star R Coronae Australis, which is about 420 light-years away. The new
portrait was taken with the Wide Field Imager at the La Silla Observatory in
Chile. The image, a combination of 12 separate snapshots in three different
colors, depicts a young family of stars still embedded in and interacting with
the cloud of dust and gas from which they formed.

The image spans about 4 light-years, and focuses on a nascent star-forming
region located in the small, tiara-shaped constellation Coronae Australis, the
Southern Crown. The infant stars there give off hot, intense radiation, and the
surrounding gas and dust either reflects or absorbs this radiation and re-emits
it at a different wavelength.

While most nebulae glow with a characteristic red tint, the R Coronae
Australis region takes an unusual blue hue. The stars are about the mass of the
sun, and don’t emit enough ultraviolet light to strip the surrounding hydrogen
gas of its electrons, which would produce the familiar red glow. The blue fog is
mostly due to starlight reflecting off small dust particles.

In some regions, like the dark band that crosses the image from the bottom
left, the starlight is completely absorbed by dust. Any stars hiding in this
region would only be visible with an infrared telescope that can detect their

High-resolution versions of the image are here.

Image: ESO

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