Concept explainers
The reason for galaxies not to go from elliptical to spiral and from spiral to elliptical.
Answer to Problem 1RQ
The galaxies cannot go from elliptical to spiral because elliptical galaxies cannot have the dense cloud required to form spiral galaxies. The spiral galaxies cannot become elliptical galaxies because they cannot lose the well defined structure.
Explanation of Solution
Elliptical galaxies have very old stars, little to no dust and there is no star formation. On the other hand, spiral galaxies have well defined disks, have a dense cloud and thus, have high rate of star formation. Also, spiral galaxies have considerable young stars.
The elliptical galaxy cannot become spiral galaxies because they lack the high density cloud and almost no young stars to be able to become spiral galaxies.
Spiral galaxies cannot become elliptical ones even if there is no new star formation. This is because the elliptical galaxies have well defined disks and it cannot have the irregularity of elliptical galaxies.
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Chapter 16 Solutions
EBK FOUNDATIONS OF ASTRONOMY
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