This object is a bipolar emission nebula located 2000 light years away in the constellation of Cygnus at a declination of +37 degrees. It is about 2 light years long and is nicknamed the Hourglass Nebula.
A young massive star, hidden in this image, emits a strong stellar wind from its poles and ionizes the gas and dust around it. Twin lobes of super-hot gas, glowing red in this image, stretch outward from each pole of the central star. This hot gas creates the ends of the hourglass. A ring of dust and gas orbiting the star acts like a belt, cinching the expanding nebula into the hourglass shape.
I find the extended surrounding nebulosity, visible most strongly at the left and right edges of the image, to be interesting. It is not clear to me how this nebulosity would have developed.
So why isn’t this object categorized as a planetary nebula? That is a good question. I usually see that a planetary nebula is defined as a shell of ionized gas ejected from a red giant star late in its life – the “last hurrah” of a star, as some say. Since this is not a star late in life, I don’t think this should be called a planetary nebula, and most sources simply refer to this object as an emission nebula. But other unusually shaped small emission objects, such as
KjPn 8, are called planetary nebula, even though they don't appear to be "late life" objects. So, despite owning numerous textbooks and studying many papers on these wonderful objects, I am still confused about the terminology.
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