An extensive was produced to accompany the documentary. The online companion covers history of cosmology, unanswered questions and other topics related to the program. It was designed to function as both a supplement to the series and a stand-alone web piece. Along with details explaining terminology, different models of the universe, biographies of famous historical figures in cosmology and content derived from the program, the web companion included discussions by contemporary cosmologists of "unsolved mysteries", an opportunity to ask questions, as well as suggestions for experiments.
One of the episodes, "On the dark side", related the possibility of hyperspace travel and explored the technology of the Star Wars franchise.