Historically, the term nebula was used by astronomers to refer to any "fuzzy" patches seen in observations. They were described as "fuzzy" or hazy extended objects, in comparison to stars, which appear as points of light, and star clusters, which are extended groupings of many stars. A nebula can either be a light patch or a dark patch, depending on its internal characteristics and how it interacts with external radiation. Sort the following images as either a nebula or not a nebula.
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some astrology imges are shown