Institute Scientist
Department of Space Studies
Southwest Research Institute
1050 Walnut Street, Suite 426
Boulder, Colorado 80302
(303) 546-9670
Fax (303) 546-9687



Ph.D., Planetary Sciences, Caltech, 1972

B.S., Physics (with highest distinction), University of Missouri, Kansas City, 1968

B.S., Mathematics, University of Missouri, Kansas City, 1968

Recent Employment

Institute Scientist, Department of Space Studies, Southwest Research Institute, June 1998 to present

Senior Research Scientist, Jet Propulsion Laboratory, June 1984 to June 1998

Awards & Recognition

Fellow, American Academy of Arts and Sciences, 2012.

Kuiper Prize, Division of Planetary Sciences, Career achievement award, American Astronomical Society, 2011

Fellow, American Association for the Advancement of Science, 2006

Alumnus of distinction, UMKC, 2006.

Fellow, American Geophysical Union, 2005

Brouwer Award, Division of Dynamical Astronomy, Career achievement award, American Astronomical Society, 2004

Asteroid (7812) Billward = 1984 UT, 1999.

Letter of Commendation, Icarus, 1998

Exceptional Scientific Achievement Medal, For discovery of Mars obliquity oscillations, NASA, 1981

Certificate of Recognition, NASA Lunar Program, 1979

NDEA Fellowship, Caltech, 1968 to 1972

Selected Service & Memberships

Division of Planetary Sciences and Division on Dynamical Astronomy, American Astronomical Society; American Association for the Advancement of Science; American Geophysical Union; International Astronomical Union; Sigma Xi Honor Society; Planetary Society Founding Member.

Lunar and Planetary Review Panel, NASA; 1980-1983, 1990-1992, 1996-1997.

Origins Review Panel, NASA, member 1998-2000; Theory Group Chief, 2001; member 2003.

Technical Thesis Advisor to J.M. Hahn, Physics Ph.D. at University of Notre Dame, 1992 to 1996

Visiting Scientist, Lunar & Planetary Institute, spring, 1997

DDA Local Arrangements Committee, Estes Park meeting, 1998; Banquet speaker "Time and Tides".

Professor Adjunct, University of Colorado, 1999-present

Icarus editorial Board, 1999-2002

Technical Thesis Advisor, C. B. Agnor,Physics Ph.D. at University of Colorado, 2001-2002.

Scientific Organizing Committee, IAP Conference on Extra-solar Planets, Paris, 2003.

Origins Review Panel, Chief Detection Group 2006; Outer Planets Research Review Panel member, 2006.

Vice-chair and Chair-elect of the Division on Dynamical Astronomy, AAS, 2006-2008.

Selected Recent Publications

Ward, W. R. 2014.Evolution of the protolunar disk. Lunar & Planetary Sci. XLV.

Ward, W. R. 2013. On the evolution of the protolunar disk. Proc. Royal Society, in press.

Ward, W. R. 2012. On the vertical structure of the protolunar disk. Astrophys. J. 744, 140-150.

Ward, W. R. Vertical structure of a two-phase pre-lunar disk. Lunar & Planetary Sci. XLII.

Ward, W. R. and R. M. Canup 2010. Circumplantary disk formation.Astron. J.140, 1168-1193.

Ward, W. R. 2009. Particle filtering by a planetary gap.Lunar & Planet Abs. XL. 40.1477W

Canup, R. M. and W. R. Ward 2009. Origin of Europa and the Galilean satellites. In Europa

(Univ. Arizona Press)

Ward, W. R. and R. M. Canup 2006. Forced resonant migration of Pluto's outer satellites by an impact-produced Charon.  Science 313, 1107-1109.


Canup, R. M. and W. R. Ward 2006. A common mass scaling for satellite systems of gaseous planets.  Nature 441, 834-839.

Ward, W. R. and R. M. Canup 2006.  The obliquity of Jupiter. Astrophys. J. Lett.640, L91-L94.

Ward, W. R. 2005.  Early clearing of the asteroid belt.  Lunar & Planetary Sci. XXXVI.

Ward, W. R., and D. P. Hamilton, 2004.  Tilting Saturn. I. Analytic model. Astron. J. 128, 2501-2509.


Hamilton, D. P. and W. R. Ward, 2004.  Tilting Saturn. II. Numerical model.  Astron. J. 128, 2510-2517.


Tanaka, H. and W. R. Ward, 2003.  Three-dimensional interaction between a planet and an isothermal gaseous disk: II. Eccentricity waves and bending waves.  Astrophys. J. 602, 388-395.

Ward, W. R. and J. M. Hahn 2003. Spiral bending waves launched at a vertical secular resonance. Astron. J. 125, 3389-3397.

Ward, W. R. 2003. The Kuiper belt as a resonant cavity.Astrophys. J. Lett. 584, L39-L42.

Ward, W. R. 2003.  Type II migration and giant planet survival.  Lunar & Planetary Sci. XXXIV.

Canup, R. M. and W. R. Ward 2003. Formation of the Galilean satellites: Conditions of accretion. Astron. J. 124, 3404-3423.

Agnor, C. B. and W. R. Ward 2002. Damping of terrestrial planet eccentricities by density wave interaction with a remnant gaseous disk.    Astrophys. J. 567, 579-586.

Canup, R. M., W. R. Ward and A. G. W. Cameron 2001. A scaling relationship for satellite-forming impacts. Icarus 158, 288-296.

Ward, W. R. and R. M. Canup 2000. Origin of the Moon's orbital inclination from resonant disk interactions. Nature 403, 741-743.

Ward, W. R. 2000. On planetesimal formation: The role of collective behavior. In Origins of the Earth & Moon (Eds. R. M. Canup and K. Righter).

W. R. Ward and J.M. Hahn, 1998. Disk-planet interactions and the formation of planetary systems. In Protostars and Planets, IV, (Eds. V. Manning, A. Boss).

Ward, W.R., and J.M. Hahn, 1998. Neptune's eccentricity and the nature of the Kuiper belt. Science, 280, 2104-2106.

Ward, W.R. and J.M. Hahn, 1998. Dynamics of the trans-Neptune region: Apsidal waves in the Kuiper disk, Astronomical Journal, 116, 489-498.

Selected Invited Presentations and Seminars:

Planetary Obliquities”, Kuiper Prize Lecture, DPS-EPSC Mtg, Nantes, Fr. Oct. 2011

Formation of circumplanetary disks” , Dept. of Applied Math and Theoretical Physics, Cambridge University, UK, Nov 2009.

The obliquities of the gas giants” Caltech, March 2006.


An overview of migration mechanisms in gaseous disks”, Aspen Winter Workshop on formation and detection of exoplanets, Feb. 2005.


Navigating the Nebula”, Brouwer Award Lecture, DDA Meeting, Cannes, Fr. April, 2004


Obliquities of the gas giants”, Kavli Institute for Theoretical Physics, March 2004.


Formation of Uranian satellites”, Workshop, Observatoire de Meudon, June 2003.


Obliquities of the giant planets” , Univ. Calf. Berkeley, Dec. 2002.


Dynamical history of the Earth-Moon system, IAU Coll.on Tides, Nanking, China, Sept. 2002.


Obliquities of the giant planets”, IAP, Paris, Sept. 2002, and Tokyo Institute of Technology , Tokyo 2002.


Formation of giant planets”, M. Mayor 60th birthday conf., Saas Fee, Switzerland, Sept. 2002.


                        Disk-planet interactions: Implications for planetary systems formation and evolution”, invited review talk at the annual meeting of the Division of Planetary Sciences/AAS, at Pasadena, CA, Oct., 2000.

Early dynamical history of the Earth-Moon system”, at Queens Univ. & Univ. Toronto, Feb., 2000.

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