When Dutch astronomer Christiaan Huygens published his detailed sketches and drawings of the Orion Nebula’s (M42) central parts (now known as Huygens’ Region) in 1659, other observers began to follow suit.
Over the next two centuries, astronomers compared the published results and pondered whether the nebula underwent periodic changes. Alternatively, they wondered: Did the differences between the drawings actually reflect more mundane issues, such as the vagaries of Earth’s atmosphere, differing telescope sizes, magnifications used, and the artist’s impression?
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