14.9: The Milky Way Galaxy’s Shape

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In his 1755 work Allgemeine Naturgeschichte und Theorie des Himmels , Immanuel Kant (1724-1804) correctly hypothesized that the Milky Way Galaxy might be a rotating body of an innumerous number of stars that were held together by gravitational forces, much like our Solar System yet on a more-grand scale. Kant based his work on that of Thomas Wright.

Here, you see a prepared sketch by William Herschel of the Milky Way Galaxy’s shape based on his 1785 star counts. Herschel believed the Solar System was at or near the center of his sketch.

Image of William Herschel’s sketch of the Milky Way Galaxy’s shape based on his 1785 star count. Sketch on white background with black point-like stars. The shape of our Galaxy as deduced from star counts by William Herschel in 1785; the solar system was assumed near center. (NOTE: The image shown is flipped 180 degrees on the horizontal axis from the original, as first published in the Philosophical Transactions of the Royal Society in 1785; the bifurcated arms of the illustration should be on the left.)

Public Domain | Image courtesy of NASA.

Provided by: Florida State College at Jacksonville. License: CC BY: Attribution