The telescope was not the instrument through which Galileo opened the skies four centuries ago, forever changing our concepts of worlds terrestrial and celestial. No, Galileo’s breakthrough was not a technological one, nor an intellectual one per se. Copernicus and Kepler had laid out the concepts before Galileo pointed his modest tube into the sky. What made all the difference, the lever that finally displaced the constraining, earth-centered Ptolemaic cosmos and ushered in a heliocentric worldview and the many advances that came in the wake of empirical science, was nothing so concrete as lenses nor so abstract as mathematical formulas. No, it was Galileo’s strategy for freely and publicly communicating his findings. Galileo opened the heavens with Open Access.