Spinning galaxies question dark matter

New ‘law of nature’ predicts galaxy rotation.

X-rays and visible light from the radio galaxy 3C31, located 240 million light-years from Earth. Calculating how fast such galaxies spin doesn't need to take dark matter into account, according to a new paper. Credit: X-ray: NASA / CXC / Univ. of Bristol / M. Hardcastle et al; Optical: NASA / STScI