The Elephant in the Universe: 100-year search for dark matter Author: Govert Schilling Theoretical Stability and Observational Proof of Dark Matter Halos

Sep 06, 11:59 PM

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The Elephant in the Universe: 100-year search for dark matter Author: Govert Schilling


Theoretical Stability and Observational Proof of Dark Matter Halos

Headline: Galaxies Need Invisible Halos: Ostriker and Rubin Provide Evidence

In the late 1960s, theorist Jeremiah Ostriker calculated that a flattened galaxy like the Milky Way could not remain stable without a large, spherical "halo" of unseen matter surrounding it, providing a theoretical basis for dark matter. This theoretical need was then powerfully confirmed by the observational work of American astronomer Vera Rubin and her colleague Kent Ford throughout the 1970s. Studying distant galaxies, including Andromeda, they discovered that stars on the outer edges rotated at unexpectedly high, constant velocities, rather than slowing down as predicted. This "flattening the curve" of rotational velocities offered the first concrete proof for the existence of dark matter, whose gravity was necessary to prevent galaxies from flying apart.

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