Mike Rowe is the narrator of How The Universe Works: Season 1. Eric Dellums voiced season 2 when it moved to the Science Channel, and Mike Rowe was asked to record season 3 and then RE-record season 2.
The narrator Erik Dellums is also the voice for Bethesdas Elder Scrolls V: Skyrim's Nazir in the Dark Brotherhood faction.
Mike Rowe also narrated Season 5.