With data like these, you can do an unprecedentedly good job at constraining cosmological parameters. Here is a plot with the density of matter on the horizontal axis, and the cosmological constant on the vertical axis, using only CMB data. Show this to any remaining friends of yours who are still skeptical about the supernova observations that revealed the acceleration of the universe (if you have such friends). This is an independent detection of the cosmological constant at better than five sigma.

Carroll Article

Chris