Today in History—July 16: The Day the End of the World Began: References & Edit History

Article Contributors

Primary Contributors

• Erik Gregersen
  Erik Gregersen is a senior editor at Encyclopaedia Britannica, specializing in the physical sciences and technology. Before joining Britannica in 2007, he worked at the University of Chicago Press on the Astrophysical Journal. Prior to that, he worked at McMaster University on the ODIN radio astronomy satellite project. 

Other Encyclopedia Britannica Contributors

• Mindy Johnston