Concept explainers
The reason the astronomers in the nineteenth-century thought that the“spiral nebulae” are a part of the Milky Way.
Explanation of Solution
Introduction:
Spiral nebulas have a very different shape when compared with other nebulas. Our Milky Way itself is a spiral galaxy with arching spiral arms that are active sites of star formation. Other nebulae are ellipse-shaped agglomerations of stars. Most galaxies are located as groups or clusters.
In 1755, the German philosopher Immanuel Kant suggested that vast collections of stars lie outside the confines of the Milky Way and introduced the concept of “island universes”. Many nineteenth-century astronomers who believed the concept of “island universe” think that the “spiral nebulae” are part of the Milky Way because they are relatively small and they look like nearby objects scattered around our galaxy like globular clusters.
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Chapter 23 Solutions
UNIVERSE (LOOSELEAF):STARS+GALAXIES
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