Figure 5: The rotation curve of the Milky Way. In the left-hand panel are the measured rotation speeds given by the average values from a number of measurements on different objects [50]. The right hand panel shows the various mass components that combine together to reproduce the observed curve between 5 and 25 kpc [72]. The dotted lines are the bulge and disk contributions, and the short-dashed curve is the dark matter contribution. The solid curve shows the combined effect of all three, and this is compared to the long-dashed curve which approximates the measured data in the left-hand panel below 25 kpc.