What evidence suggests that the Milky Way contains dark matter?
Answer
A) We observe clouds of atomic hydrogen far from the galactic center orbiting the galaxy at unexpectedly high speeds, higher speeds than they would have if they felt only the gravitational attraction from objects that we can see.B) We see many lanes of dark material blocking out the light of stars behind them along the band of the Milky Way.
C) We see many dark voids between the stars in the halo of the Milky Way.
D) When we observe in different wavelengths, such as infrared or radio, we see objects that don't appear in visible-light observations.
E) When we look at the galactic center, we are able to observe a large black hole that is composed of dark matter.
