Dark Matter in the Universe

Dark Matter in the Universe

coma-galaxy-annotatedIn 1933, Swiss astronomer Fritz Zwicky discovered that the visible matter contained in the galaxies of the vast Coma cluster is barely 10% of the amount needed to keep the galaxies bound together. This is the first indication that the universe has vast quantities of dark matter, which gives off no light but possesses gravity. Recent observations by the European Space Agency’s Planck satellite show this still mysterious stuff makes up 27% of the mass-energy content of the universe, more than 5 times what normal matter contributes.