The Calabash Nebula, also known as the Rotten Egg Nebula is a protoplanetary nebula 1.4 light years long and located some 5,000 light years from Earth in the constellation Puppis. Violent gas collisions that produced supersonic shock fronts in a dying star are seen in a new, detailed image from NASA's Hubble Space Telescope. The object is sometimes called the Rotten Egg Nebula because it contains a relatively large amount of sulfur. The densest parts of the nebula are composed of material ejected recently by the central star and accelerated in opposite directions. This material, shown as yellow in the image, is zooming away at speeds up to one and a half million kilometers per hour (one million miles per hour). Most of the star's original mass is now contained in these bipolar gas structures.
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