Anne’s Picture of the Day: Emission Nebula NGC 6164

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February 15, 2013

NGC 6164, an emission nebula in Norma

Image Credit & Copyright: Don Goldman, Astrodon Imaging (http://www.astrodonimaging.com)

NGC 6164 is a bipolar emission nebula of about 4 light-years across that lies some 4,200 light-years away from Earth in the southern constellation of Norma. It is approaching us at approximately 53.9 kilometers per second.

Its symmetric gaseous shroud and faint halo surround the blue, young, central star HD 148937, the brightest member of a triple star system orbiting around each other, which fierce stellar winds – of about 8 million kilometers per hour – created this nebula. This hot, luminous O-type star is some 40 times as massive as the Sun and just 3 to 4 million years old. In another 3 to 4 million years the massive star will end its life in a supernova explosion.

NGC 6164’s bipolar symmetry, as well as its extensive halo makes it similar in appearance to planetary nebulae – the gaseous shrouds surrounding dying Sun-like stars. Expanding into the surrounding interstellar medium, the material in this halo is likely from an earlier outburst of the central star, about 4000 years ago.

This image is a composite of narrow-band image data highlighting the glowing gas, and broad-band data of the surrounding starfield.

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