Gregory Whiffen

  • Program Years: 1991-1995
  • Academic Institution: Cornell University
  • Field of Study: Environmental Systems Engineering
  • Academic Advisor: Christine Shoemaker
  • Practicum(s):
    Argonne National Laboratory (1992)
  • Degree(s):
    Ph.D. Environmental Systems Engineering, Cornell University, 1995
    M.S. Environmental Systems Engineering, Cornell University, 1993
    B.S. Math, B.S. Astronomy and B.S. Physics, with honors University of Wisconsin-Madison, 1987

Current Status

  • Status: Principal Engineer, Outer Planets Mission Design Group, NASA Jet Propulsion Laboratory, Pasadena CA.
  • Research Area: Deep Space Trajectory and Mission Design, Low-Thrust Mission Design, and Nonlinear Optimal Control


Dr. Whiffen is currently developing trajectories for NASA's Dawn Discovery Mission to orbit the giant metallic asteroid Psyche launching in 2022. Previously, Dr. Whiffen served as lead mission designer on the Dawn mission to asteroid Vesta and dwarf planet Ceres. Dawn used ion propulsion. If a spacecraft's capability is measured by its ability to change its velocity, then Dawn will be the most capable spacecraft ever launched by a factor of three. This tremendous propulsive capability is required to visit and stay at both Vesta and Ceres.


(Selected Publications)
Mathis J.S., Whiffen G., "Composite Interstellar Grains," Astrophysical Journal, 341, pp808-822, 1989.
Whiffen G.J., Shoemaker C.A., "Nonlinear Weighted Feedback Control of Groundwater Remediation Under Uncertainty," Water Resources Research, 29(9), pp3277-3289, 1993.
Whiffen G.J,, "Static/Dynamic for Optimizing a Useful Objective," United States Patent No. 6,496,741, Issued 12/17 2002, Filed 3/35 1999.
Whiffen G.J., Sims, J.A., "Application of SDC Optimal Control Algorithm to Low-Thrust Escape and Capture Including Fourth Body Effects," 2nd International Symposium on Low Thrust Trajectories, Toulouse, France, June 18-20, 2002
Whiffen G.J., "An Investigation Of a Jupiter Galilean Moon Orbiter Trajectory," Paper AAS03-544, AAS/AIAA Astrodynamics Specialists Conference, 2003.
Whiffen G.J., "Optimal Low-Thrust Orbital Transfers Around a Rotating Non-Spherical Body," Paper AAS04-264, AAS/AIAA Space Flight Mechanics Meeting, 2004.
Whiffen G.J., "Jupiter Icy Moons Orbiter Reference Trajectory," Paper 06-186, AAS/AIAA Space Flight Mechanics Conference, 2006.
Whiffen G.J., "The Stability of Powered Flight Around Asteroids With Application to Vesta", Paper 11-186, Proceedings of the AIAA/AAS Astrodynamics Specialist Conference, New Orleans, Louisiana, Feb 13-17, 2011
Whiffen G.J., "Low Altitude Mapping Orbit Design and Maintenance For the Dawn Discovery Mission at Vesta," Paper 11-182, Proceedings of the AIAA/AAS Astrodynamics Specialist Conference, New Orleans, Louisiana, Feb 13-17, 2011


Co-recipient of International SpaceOps Award for Outstanding Achievement for 2021
NASA Honors Award, Exceptional Engineering Achievement Medal, 2016
Elected to Pi Mu Epsilon National Mathematics Honorary Society, as a person who has special distinction in mathematics, 2016
Co-recipient Collier Trophy, for Greatest Achievement in Aeronautics and Astronautics in America, 2015
NASA Honors Award, Exceptional Achievement Medal, 2013
NASA Honors Award, Exceptional Achievement Medal, 2008.
Jet Propulsion Laboratory, 2008 Explorer Award, Outstanding innovation and technical excellence.
Jet Propulsion Laboratory, 2007 Ranger Award, Dawn mission support.
Jet Propulsion Laboratory, 2007 Mariner Award, for increasing the number and quality of Cassini's Enceladus flybys.
Phi Beta Kappa (University of Wisconsin)