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 Asteroids, Comets & Satellites (3224): People
Bruce  Bills's Picture
Jet Propulsion Laboratory
M/S 183-301
4800 Oak Grove Drive
Pasadena, CA 91109
818 393-6307
818 393-4445
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Curriculum Vitae:

Bruce Bills

  • Ph.D., California Institute of Technology, Planetary Science / Geophysics, (1978)
  • B.S., Brigham Young University, Mathematics / Physics, (1973)

Professional Experience
  • Jet Propulsion Laboratory, Pasadena, California, (2008-present)
  • Visiting Research Geophysicist, Scripps Institution of Oceanography, La Jolla, California, (1998-present)
  • Geophysicist, Geodynamics Branch, Goddard Space Flight Center, Greenbelt, Maryland, (1990-2008)
  • Adjunct Professor, Department of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, Maryland, (1991-1998)
  • Staff Scientist, Lunar and Planetary Institute, Houston, Texas, (1984-1990)
  • Jet Propulsion Laboratory, Pasadena, California, (1977-1984)
    • Senior Scientist, Planetary Radar Group, Earth and Space Sciences Division, (1983-1984)
    • Senior Scientist, Planetary Dynamics and Geophysics Group, Earth and Space Sciences Division, (1979-1983)
    • Senior Engineer, Tracking and Orbit Determination Group, Systems Division, (1977-1979)

Selected Awards
  • NASA Group Achievement Award, Dawn Science Team (2013)

Selected Publications

104 Vance, S.D., B.G. Bills, et al. (2018),  Geophysical investigations of habitability in ice-covered ocean worlds, J. Geophys. Res., 123, 180-205.

103 Konopliv, A.S., B.G. Bills, et al. (2017),  The Ceres gravity field, spin pole, rotation period and orbit, Icarus, 299, 411-429.

102 Bills, B.G., B.R. Scott (2017),  Secular obliquity variations of Ceres and Pallas, Icarus, 284, 59-69.

101 Adams, K.D., B.G. Bills, (2016),. Isostatic rebound and palinspastic restoration of the Bonneville and Provo shorelines in the Bonneville Basin, UT, NV, and ID. In: Oviatt, C.G., Shroder Jr., J. (Eds.). Lake Bonneville: A Scientific Update. Elsevier B.V., vol. 20, pp 88-104.

100 Park, R.S., B.G. Bills, et al. (2016),  A partially differentiated interior for (1) Ceres deduced from its gravity field and shape, Nature, 537, 515-517.

99   Romero-Wolf, A., B.G. Bills, et al. (2016),  Prospects of passive radio detection of a subsurface ocean on Europa Plan. Space Sci., 129, 118-121.

98   Hurford, T.A., B.G. Bills, et al. (2014), Tidal disruption of Phobos as the cause of surface fractures, J. Geophys. Res., 121, 1054-1065.

97   Oviatt, C.G., B.G. Bills, et al. (2014),  Interpretation of evidence for large Pleistocene paleolakes in the Bonneville basin, Paleogeo. Paleoclim. Paleoeco., 401, 173-176

96   Park, R.S., B.G. Bills, et al. (2014),  Gravity field expansion in ellipsoidal harmonics applied to Vesta, Icarus, 240, 118-132.

95   Konopliv, A.S. B.G. Bills, et al. (2014),  The Vesta gravity field, spin pole and rotation period, Icarus, 240, 103-117.

94   Bills, B.G., S.W. Asmar, A.S. Konopliv et al. (2014),  Harmonic and statistical analyses of the gravity and topography of Vesta, Icarus, 240, 161-173.

93   Siegler, M.A., B.G. Bills, D.A. Paige (2013),  Orbital eccentricity driven temperature variation at Mercury’s poles, J. Geophys. Res., 118, 930-937.

92   Pappalardo, R.T., B.G. Bills, et al. (2013),  Science potential of a Europa lander, Astrobiology, 13, 740-773.

91   Konopliv, A.S., S.W. Asmar, B.G. Bills, N. Mastrodemos, R.S. Park, C.A. Raymond, D.E. Smith, M.T. Zuber (2011),  The DAWN gravity investigation at Vesta and Ceres, Space Sci. Rev., 163, 461-486.

90   F. Nimmo, B.G. Bills, P.C. Thomas (2011),  Geophysical implications of the long-wavelength topography of the Saturnian satellites, J. Geophys. Res., 116, E11001.

89   Park, R.S., S.W. Asmar, B. Buffington, B.G. Bills, S. Campagnola, P. W. Chodas, W. M. Folkner, A.S. Konopliv, and A.E. Petropoulos (2011),  Detecting tides and gravity at Europa from multiple close flybys, Geophys. Res. Lett., (nov 2011)

88   Bills, B.G., and F. Nimmo (2011),  Rotational dynamics and internal structure of Titan , Icarus, 214, 351-355.

87   Bills, B.G., and F. Nimmo (2011),  Forced obliquities and moments of inertia of Ceres and Vesta, Icarus, 213, 496-509.

86   Siegler, M.A., B.G. Bills, and D.A. Paige (2011),  Effects of orbital evolution on lunar ice stability, J. Geophys. Res., 116, E03010.

85   D.A. Paige, B.G. Bills, and 23 others (2010),  Diviner lunar radiometer observations of cold traps in the Moon’s south polar region, Science, 330, 479-482.

84   Nimmo, F., B.G. Bills, P.C. Thomas, and S.W. Asmar (2010),  Geophysical implications of the long-wavelength topography of Rhea, J. Geophys. Res., 115, E10008.

83   Weber, R.C., B.G. Bills, and C.L. Johnson (2010),  A simple physical model for deep moonquake occurrence times, Phys. Earth Plan. Inter., 182, 152-160.

82   Matsuyama, I., and B.G. Bills (2010),  Global contraction of planetary bodies due to despinning: Application to Mercury and Iapetus, Icarus, 29, 271-279.

81   Nimmo, F. and B.G. Bills (2010),  Shell thickness variations and the long-wavelength topography of Titan, Icarus, 208, 896-904.

80   Bills, B.G., F. Nimmo, O. Karatekin, T. Van Hoolst, N. Rambaux, B. Levrard, and J. Laskar (2010),  Rotational dynamics of Europa, in Europa, eds. R. Pappalardo, W. McKinnon, and K. Khurana, Univ. Arizona Press.

79   Weber, R.C., B.G. Bills, and C.L. Johnson, (2009),  Constraints on deep moonquake focal mechanisms through analysis of tidal stress, J. Geophys. Res., 114, E05001

78   Hurford, T.A., B.G. Bills, P. Helfenstein, R. Greenberg, G.V. Hoppa, and D.P. Hamilton (2009),  Geological implications of a physical libration on Enceladus, Icarus, 203, 541-552

77   Hurford, T.A., A.R. Sarid, R. Greenberg, and B.G. Bills (2009) The influence of obliquity on Europan cycloid formation, Icarus, 202, 197-215.

76   B.G. Bills (2009),  Tidal flows in satellite oceans, Nature Geoscience, 2, 13-14

75   Borsa, A.A., B.G. Bills, and J.B. Minster (2008) Modeling the topography of the salar de Uyuni, Bolivia, as an equipotential surface of Earth’s gravity field, J. Geophys. Res., B10408.

74   B.G. Bills, and F. Nimmo (2008),  Forced obliquity and moments of inertia of Titan, Icarus, 196, 293-297.

73   Hurford, TA., P. Helfenstein, G.V. Hoppa, R. Greenberg, and, B.G. Bills (2007),  Eruptions arising from tidally controlled periodic openings of rifts on Enceladus, Nature, 447, 292-294.

72   Bulow, R.C., C.L. Johnson, B.G. Bills, and P.M. Shearer (2007),  Temporal and spatial properties of some deep Moonquake clusters, J. Geophys. Res., 112, E09003.

71   Luttrell, K., D Sandwell, B. Smith-Konter, B.G. Bills, and Y. Bock (2007),  Modulation of the earthquake cycle at the southern San Andreas fault by lake loading J. Geophys. Res., 112, B08411.

70   Borsa, A., H.A. Fricker, B.G. Bills, J-B, Minster, C. Carabajol, and K. Quinn (2008),  Topography of the salar de Uyuni, Bolivia from kinematic GPS, Geophys. J. Int.., 172, 31-40.

69   Borsa, A.A., J-B Minster, B.G. Bills, and H A. Fricker (2007),  Modeling long-period noise in kinematic GPS applications, J. Geodesy, 81, 157-170.

68   Bills, B.G., A.A. Borsa, and R.L. Comstock (2007),  MISR-based passive optical bathymetry from orbit with cm-level accuracy on the salar de Uyuni, Bolivia Remote. Sens. Environ., 107, 240-255.

67   Bills, B.G., K.D. Adams, and S.G. Wesnousky (2007),  Viscosity structure of the crust and upper mantle in western Nevada from isostatic rebound patterns of Lake Lahontan shorelines, J.Geophys. Res., 112, B06405..

66   Bills, B.G., (2005),  Variations in the rotation rate of Venus due to orbital eccentricity modulation of solar tidal torques, J. Geophys. Res. Planets, 110, E11007.

65   Fricker, H.A., A.A. Borsa, J.B. Minster, C. Carabajal, K. Quinn, and B.G. Bills (2005),  Assessment of ICESat performance at the salar de Uyuni, Bolivia Geophys. Res. Lett. 32, L21S06.

64   Munk, W.H., and B.G. Bills (2007),  Tides and the climate: some speculations, J. Phys. Ocean. 37, 135-147.

63   Bills, B.G., G.A. Neumann, D.E. Smith, and M.T. Zuber (2005),  Improved estimate of tidal dissipation within Mars from MOLA observations of the shadow of Phobos, J. Geophys. Res. Planets, 110, E07004.

62   B.G. Bills, and R.L. Comstock (2005),  Forced obliquity variations of Mercury, J. Geophys. Res. Planets, 110, E04006.

61   B.G. Bills, and R.L. Comstock (2005),  Spatial and temporal patterns of solar eclipses by Phobos on Mars, J. Geophys. Res. Planets, 110, E04004.

60   B.G. Bills (2005),  Free and forced obliquities of the Galilean satellites of Jupiter, Icarus, 175, 233-247.

59   Egbert, G.D., R.D. Ray, and B.G. Bills (2004),  Numerical modeling of the global semidiurnal tide in the present day and in the last glacial maximum, J. Geophys. Res. Oceans, 109, C03003.

58   Comstock, R.L., and B.G. Bills (2003),  A solar system survey of forced librations in longitude, J. Geophys. Res. Planets, 108, 5100.

57   Bills, B.G., T.J. Wambeam, and D.R. Currey (2002),  Geodynamics of Lake Bonneville, in Great Salt Lake: An overview of change, , ed. J. Wallace Gwynn, Utah Geol. Survey, pp. 7-32.

56   Bills, B.G., and R.S. Nerem (2001),  Mars topography: Lessons learned from spatial and spectral domain comparisons of Mars Orbiter Laser Altimeter and U.S. Geological Survey data, J. Geophys. Res., 106, 32, 915-32, 925.

55   Bills, B.G., and R.D. Ray (2000),  Galilean satellite obliquities, J. Geophys. Res., 105, 29.277-29, 282.

54   Clifford, S.M., B.G. Bills et al. (2000),  The state and future of Mars polar science and exploration, Icarus, 144, 210-242.

53   Bills, B.G., and R.D. Ray (1999),  Lunar orbital evolution: Synthesis of recent results, Geophys. Res. Lett. 26, 3045-3048.

52   Bills, B.G. (1999),  Obliquity-oblateness feedback on Mars, J. Geophys. Res. 104, 30, 773-30, 798.

51   Ray, R.D., B.G. Bills, and B.F. Chao (1999),  Lunar and solar torques on the oceanic tides, J. Geophys. Res. 104, 17, 653-17, 659.

50   Adams, K.D., S.G. Wesnousky, and B.G. Bills (1999),  Isostatic rebound, active faulting, and potential geomorphic effects in the Lake Lahontan Basin, Nevada and CaliforniaGeol. Soc. Amer. Bull., 111, 1739-1756.

49   Tackman, G.E., B.G. Bills, T.S. James, and D.R. Currey (1999),  Lake gauge evidence for regional postglacial tilting in Southern ManitobaGeol. Soc. Amer. Bull., 111, 1684-1699.

48   Bills, B.G., J.G. Mengel, and T.S. James (1999),  Climatic impact of glacial cycle polar motion: Coupled oscillations of ice sheet mass and rotation pole position, J. Geophys. Res., 104, 1059-1075.

47   Bills, B.G. (1999),  Tidal despinning of the mantle, inner core super-rotation, and outer core effective viscosityJ. Geophys. Res. 104, 2653-2666.

46   Bills, B.G., and T.S. James (1999),  Moments of inertia and rotational stability of Mars: Lithospheric support of sub-hydrostatic rotational flattening, , J. Geophys. Res. 104, 9081-9096.

45   Tackman, G.E., D.R. Currey, B.G. Bills, and T.S. James (1998),  Paleoshoreline evidence for postglacial tilting in Southern Manitoba, J. Paleolimnology, 19, 343‑363.

44   Bills, B.G., and T.S. James (1997),  Polar motion of a viscoelastic Earth due to glacial cycle mass loading, J. Geophys. Res. 102, 7579-7602.

43   Folkner, W.M., R.D. Kahn, R.A. Preston, C.F. Yoder, C.D. Edwards, R. Hellings, E. M. Standish, M. Eubanks, and B.G. Bills (1997),  Mars dynamics from Earth-based tracking of the Mars Pathfinder Lander, J. Geophys. Res. 102, 4057-4064.

42   Shirron, P.J, M.J DiPirro, S.H. Castles, B.G. Bills, H.J Paik, E.R. Canavan and M.V. Moody (1996),  Mission concepts for the Superconducting Gravity Gradiometer, Cryogenics, 36, 805-813.

41        Bills, B.G., and T.S. James (1996),  Late Quaternary variations in relative sea level due to glacial cycle polar wander, Geophys. Res. Lett. 23, 3023-3026.

40   Frey, H.V., B.G. Bills, R.S. Nerem, and J.H. Roark (1996),  The isostatic state of Martian topography revisited, Geophys. Res. Lett. 23, 721-724.

39   Kiefer, W.S., B.G. Bills, and R.S. Nerem (1996),  An inversion of gravity and topography for mantle and crustal structure on Mars, J. Geophys. Res. 101, 9239-9252.

38   Bills, B.G., and F.G. Lemoine (1995),  Gravitational and topographic isotropy of the Earth, Moon, Mars and Venus, J. Geophys. Res. 100, 26, 275-26, 295

37   Bills, B.G. (1995)Discrepant estimates of the moments of inertia of the Moon J. Geophys. Res. 100, 26, 297-26, 303.

36   Bills, B.G., and D.P. Rubincam (1995),  Constraints on density models from radial moments: Application to the Earth, Moon and Mars, J. Geophys. Res. 100, 26, 305-26, 315.

35   Bills, B.G., and R.R. Nerem (1995),  A harmonic analysis of Martian topography, J. Geophys. Res. 100, 26, 317-26, 326.

34   Bills, B.G., D.R. Currey, and G.A. Marshall (1994),  Viscosity estimates for the crust and upper mantle from patterns of lacustrine shoreline deformation in the eastern Great Basin, J. Geophys. Res., 99, 22, 059-22, 086.

33   Bills, B.G., S.L. de Silva, D.R. Currey, R.S. Emenger, K. Lillquist, A. Donnellan, and B. Worden (1994),  Hydro-isostatic deflection and tectonic tilting in the Central Andes: Initial results of a GPS survey of Lake Minchin shorelines, Geophys. Res. Lett., 21, 293-296.

32   Bills, B.G. (1994)Obliquity-oblateness feedback: Are climatically sensitive values of obliquity dynamically unstable?Geophys. Res. Lett., 21, 177-180.

31   Nerem, R.S., B.G. Bills, and J.B. McNamee (1993),  A high resolution gravity model for Venus: GVM-1, Geophys. Res. Lett., 20, 599-602.

30   Bills, B.G. (1993),  Geodynamic contributions to global climatic change, in Orbital, Rotational and Climatic Interactions, NASA Conf. Publ. 3815, pp. 1-33.

29   Bills, B.G., and M.A. Fischer (1992),  A spatial domain Stokes flow model for the gravity and topography of the middle latitudes of Venus, J. Geophys. Res., 97, 18, 285-18, 294.

28   Esposito, P.B., W.B. Banerdt, G.F. Lindal, W.L. Sjogren, M.A. Slade, B.G. Bills, D.E. Smith, and G. Balmino, Gravity and topography, in Mars, edited by H.H. Kiefer, B.M. Jakosky, C.W. Snyder and M.S. Mathews, University of Arizona Press, pp. 209-248.

27   Bills, B.G. (1992),  Venus: Satellite orbital decay, ephemeral ring formation, and subsequent crater production, Geophys. Res. Lett., 19, 1025-1028.

26   May, G.M., B.G. Bills, and D.S. Hodge (1991),  Far-field flexural response of Lake Bonneville from paleopluvial lake elevations, Phys. Earth Planet. Inter., 68, 274-284.

25   Bills, B.G. (1990),  The rigid body obliquity history of Mars, J. Geophys. Res., 95, 14, 137-14, 153.

24   Bills, B.G. (1990),  Geodetic constraints on the composition of Mars, J. Geophys. Res., 95, 14, 131-14, 136.

23   Bills, B.G. (1989),  Comment on "More about the moment of inertia of Mars", Geophys. Res. Lett., 11, 1337-1338.

22   Bills, B.G. (1989),  Planetary geodesy, in The Encyclopedia of Solid Earth Geophysics, edited by D.E. James, Van Nostrand Reinhold, pp. 931-938.

21   Bills, B.G. (1989),  The moments of inertia of Mars, Geophys. Res. Lett., 16, 385-388.

20   Herrick, R.R., B.G. Bills, and S.A. Hall (1989),  Variations in effective compensation depth across Aphrodite Terra, Venus, Geophys. Res. Lett., 16, 543-546.

19   Bills, B.G., and G.M. May (1987),  Lake Bonneville: Constraints on lithospheric thickness and upper mantle viscosity from isostatic warping of shorelines, J. Geophys. Res., 92, 11, 493-11, 508.

18   Bills, B.G., W.S. Kiefer, and R.L. Jones (1987),  Venus gravity: A harmonic analysis, J. Geophys. Res., 92, 10, 335-10, 351.

17   Bills, B.G., and S.P. Synnott (1987),  Planetary geodesy, Rev. Geophys., 25, 833-839.

16   Nakamura, Y., J. Oberst, S.M. Clifford, and B.G. Bills (1986),  Comments on the letter "On the influx of small comets into the Earth's upper atmosphere", Geophys. Res. Lett., 13, 1184-1185.

15   Kiefer, W.S., M.A. Richards, B.H. Hager, and B.G. Bills (1986),  A dynamic model of Venus's gravity field, Geophys. Res. Lett., 13, 14-17.

14   Mottinger, N.A., W.L. Sjogren, and B.G. Bills (1985),  Venus gravity: A harmonic analysis and geophysical implications, J. Geophys. Res., 90, C739-C756.

13   Bills, B.G., and M. Kobrick (1985),  Venus topography: A harmonic analysis, J. Geophys. Res., 90, 827-836.

12   Sjogren, W.L., B.G. Bills, and N.A. Mottinger (1984),  Venus: Ishtar gravity anomaly, Geophys. Res. Lett., 11, 489-491.

11   Reasenberg, R.D., and B.G. Bills (1983),  Critique of "Elastic thickness of the Venus lithosphere estimated from topography and gravity", Geophys. Res. Lett., 10, 93-96.

10   Sjogren, W.L., B.G. Bills, P.W. Birkeland, P.W. Esposito, A.R. Konopliv, N.A. Mottinger, S.J. Ritke, and R.J. Phillips (1983),  Venus gravity anomalies and their correlation with topography, J. Geophys. Res., 88, 1119-1128.

9     Bills, B.G. (1983),  Thermoelastic bending of the lithosphere, Geophys. J. Roy. Astr. Soc., 75, 169-200.

8     Esposito, P.B., W.L. Sjogren, N.A. Mottinger, B.G. Bills, and E. Abbott (1982),  Venus gravity: Analysis of Beta Regio, Icarus, 51, 448-459.

7     Ananda, M.P., W.L. Sjogren, R.J. Phillips, and B.G. Bills (1980),  A low-order global gravity field of Venus and dynamical implications, J. Geophys. Res., 85, 8303-8318.

6     Bills, B.G., and A.J. Ferrari (1980),  A harmonic analysis of lunar gravity, J. Geophys. Res., 85, 1013-1025.

5     Ferrari, A.J., and B.G. Bills (1979),  Planetary geodesy, Rev. Geophys. Space Phys., 17, 1663-1677.

4     Bills, B.G., and A.J. Ferrari (1978),  Mars topography harmonics and geophysical implications, J. Geophys. Res., 83, 3497-3508.

3     Bills, B.G., and A.J. Ferrari (1977),  A lunar density model consistent with topographic, gravitational, librational and seismic data, J. Geophys. Res., 82, 1306-1314.

2     Bills, B.G., and A.J. Ferrari (1977),  A harmonic analysis of lunar topography, Icarus, 31, 244-259.

1          McNamara, D.H., and B.G. Bills (1973),  Photometric and spectrographic observations of HR6684, Pub. Astron. Soc. Pac., 85, 632-636.

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