The WorldWide Telescope (WWT) software environment gives explorers a Universe at their fingertips. Views of the Sky at wavelengths invisible to the human eye, virtual "3D" space travel, and seamless connections to the ever-expanding web of information online about our understanding of the Universe are available to anyone seeking to explore. WWT lets teachers and students learn in completely new, more engaging and data-rich ways, and it lets scientists communicate results, and share and contextualize data much more effectively than they ever have before. In this short article, written to commemorate the full "open-sourcing" of WorldWide Telescope software by Microsoft in 2015, we highlight just a few of the ways WWT has, and will continue to, change education, research, and scholarly communication. Detailed examples of how WorldWide Telescope is used in various settings are described at wwtstories.org.