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Dr. Kevin R. Grazier is the scientific advisor for the Re-imagined Series, and one of two writers of The Science of Battlestar Galactica—a book discussing the science depicted and hinted at in the Re-imagined Series.
Grazier earned B.S. degrees in Computer Science and Geology from Purdue University, and a B.S. in Physics from Oakland University, as well as M.S. degrees in physics from Purdue and Geophysics and Space Physics from UCLA. He did his Ph.D. in Planetary Physics at UCLA, and his dissertation title was "The Stability of Planetesimal Niches in the Outer Solar System: A Numerical Investigation". 
He currently works at NASA's Jet Propulsion Laboratory (JPL) on the Cassini/Huygens Mission to Saturn. In addition to that he is teaching classes in astronomy, planetary science and cosmology at UCLA and Santa Monica College, and is a planetarium lecturer at LA's Griffith Observatory.
Grazier's involvement in Battlestar Galactica started when he worked alongside Richard Hatch in Battlestar Galactica: The Second Coming, in which he was Hatch's scientific advisor, general "jack of all trades," and portrayed a Centurion in Hatch's proof-of-concept trailer. Due to his work with Hatch, Hatch attempted to pitch Grazier to Ronald D. Moore during their initial discussions regarding the character of Tom Zarek. While Moore said they already had someone in mind, neither person knew they were talking about the same person -- as Bryan Fuller (Star Trek:Voyager, Dead Like Me) had brought Grazier to Moore's attention previously.
For the Re-imagined Series, Grazier typically supplies the production with information related to astronomy and general space information. He also admits to coming up with occasional technobable for scripts, the usage of which is typically saddled on James Callis' shoulders.