Astronomers have discovered the Milky Way's disk is warped and twisted, not flat like a pancake. The authors hypothesize that as the Milky Way’s inner disk of stars rotates, it drags on the outer disk as well, distorting the flat spiral.

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Astronomers have discovered the Milky Way's disk is warped and twisted, not flat like a pancake. The authors hypothesize that as the Milky Way’s inner disk of stars rotates, it drags on the outer disk as well, distorting the flat spiral.