The Cosmic Microwave Background is the most accurately measured and mapped stellar phenomenon known to scientists. The history, however, surrounding its early detection and later confirmation is generally distorted. This story illustrates much about how science can be serendipitous and requires theory to inform both observations and conclusions.

One of the most pressing problems facing today’s astronomers and cosmologists is that of ‘dark matter.’ Given the prominent role played by dark matter in modern astronomy and cosmology, it’s important to understand the history of dark matter. This story examines the eccentric scientists Fritz Zwicky and Vera Rubin and how they concluded that dark matter exists.

Neptune, the first planet to be found by mathematical prediction rather than empirical observation was discovered on September 23, 1846 by two astronomers and one mathematician working independently in different countries. This story illustrates important aspects of how science works and exemplifies the social nature of science.

On April 26, 1920, astronomer Harlow Shapley took the podium at the annual meeting of the National Academy of Sciences to argue against the existence of external galaxies, also called ‘island universes.’ His opponent, Heber D. Curtis, followed Shapley’s speech with a technical and dense speech arguing for the existence of island universes, sparking what was later called “Great Debate”.