New image of a rare blue nebula

This blue cloud of gas and dust is a star-forming region around the star R Coronae Australis, which is 420 light years away. The picture was taken from the La Silla Observatory in Chile. The image is a combination of 12 separate images in three different colors, depicting a young family of stars still in the mother cloud and interacting with it.



The image spans about 4 light-years and focuses on a star-forming region located in a small cluster in the Southern Crown. Young stars emit powerful radiation and the surrounding gas and dust reflect and absorb this radiation, releasing again from another long wave.

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At a time when most of the nebulae glow with a characteristic red glow, the R Coronae Australis region has an unusual bluish tint. The stars there have a mass approximately equal to the mass of the Sun and do not emit enough ultraviolet light to knock electrons from the orbits of the surrounding hydrogen, which would create the usual red glow.



In some regions, such as in the photo on the left below, light is completely absorbed by dust. Any stars located in this region can be detected only with the help of IR telescopes that record their heat.



Hi-res image: http://www.eso.org/public/images/eso1027a/ (specifically here: http://www.eso.org/public/archives/images/screen/eso1027a.jpg )