Isamu M Matsuyama

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Scholarly Contributions

Chapters

• Keane, J. T., Matsuyama, I., Bierson, C. J., & Trinh, A. (2023). Tidal Heating and the Interior Structure of Io. In Io: A New View of Jupiter’s Moon(pp 95-146). Springer International Publishing.

Journals/Publications

• Andrews-Hanna, J. C., Weber, R. C., Garrick-Bethell, I., Evans, A. J., Kiefer, W. S., Grimm, R. E., Keane, J. T., Laneuville, M., Ishihara, Y., Kamata, S., & Matsuyama, I. (2023). The Structure and Evolution of the Lunar Interior. Reviews in Mineralogy and Geochemistry, 89(1), 243-292.
• Downey, B. G., Nimmo, F., & Matsuyama, I. (2023). The thermal-orbital evolution of the Earth-Moon system with a subsurface magma ocean and fossil figure. Icarus, 389, 115257.
• Gevorgyan, Y., Matsuyama, I., & Ragazzo, C. (2023). Equivalence between simple multilayered and homogeneous laboratory-based rheological models in planetary science. Monthly Notices of the Royal Astronomical Society, 523(2), 1822-1831.
• Rovira-Navarro, M., Matsuyama, I., & Berne, A. (2023). A Spectral Method to Compute the Tides of Laterally-Heterogeneous Bodies. arXiv e-prints, arXiv:2311.15710.
• Rovira-Navarro, M., Matsuyama, I., & Hay, H. C. (2023). Thin-shell Tidal Dynamics of Ocean Worlds. The Planetary Science Journal, 4(2), 23.
• Hay, H., Matsuyama, I., & Pappalardo, R. (2022). The High-Frequency Tidal Response of Ocean Worlds: Application to Europa and Ganymede. Journal of Geophysical Research (Planets), 127(5), e07064.
• Matsuyama, I. N., Steinke, T., & Nimmo, F. (2022). Tidal Heating in Io. Elements, 18(6), 374--378.
• Johnson, P. E., Keane, J. T., Young, L. A., & Matsuyama, I. (2021). New Constraints on Pluto's Sputnik Planitia Ice Sheet from a Coupled Reorientation-Climate Model. The Planetary Science Journal, 2(5), 194.
• Matsuyama, I., Keane, J., Trinh, A., Beuthe, M., & Watters, T. (2021). Global tectonic patterns of the Moon. Icarus, 358, 114202.
• Matsuyama, I., Trinh, A., & Keane, J. T. (2021). The Lunar Fossil Figure in a Cassini State. The Planetary Science Journal, 2(6), 232.
• Sutton, S. S., Moullet, A., McEwen, A. S., Matsuyama, I., Harris, W. M., Keane, J., Ahern, A. A., Bagenal, F., Mlinar, A. C., Basu, K., Becerra, P., Bertrand, T., Beyer, R. A., Bierson, C. J., Bland, M. T., Breuer, D., Davies, A. G., Kleer, K. d., Pater, I. d., , DellaGiustina, D. N., et al. (2021). The Science Case for Io Exploration. Bulletin of the AAS, 53(4). doi:10.3847/25c2cfeb.f844ca0e
• Sutton, S. S., Noonan, J. W., Matsuyama, I., Keane, J., Ahern, A. A., Bagenal, F., Mlinar, A. C., Basu, K., Becerra, P., Bertrand, T., Beyer, R. A., Bierson, C. J., Bland, M. T., Breuer, D., Davies, A. G., Kleer, K. d., Pater, I. d., DellaGiustina, D. N., Denk, T., , Echevarria, A., et al. (2021). Recommendations for Addressing Priority Io Science in the Next Decade. Bulletin of the AAS, 53(4). doi:10.3847/25c2cfeb.3de45b59
• Bouley, S., Keane, J. T., Baratoux, D., Langlais, B., Matsuyama, I. M., Costard, F., Hewins, R., Payré, V., Sautter, V., Séjourné, A., Vanderhaeghe, O., & Zanda, B. (2020). A thick crustal block revealed by reconstructions of early Mars highlands. Nature, 13(2), 105-109.
• Downey, B. G., Nimmo, F., & Matsuyama, I. (2020). Inclination damping on Callisto. Monthly Notices of the Royal Astronomical Society, 499(1), 40-51.
• Hay, H. C., Trinh, A., & Matsuyama, I. (2020). Powering the Galilean Satellites with Moon-Moon Tides. Geophysical Research Letters, 47(15), e88317.
• Matsuyama, I., Downey, B. G., & Nimmo, F. (2020). Inclination damping on Callisto. Monthly Notices of the Royal Astronomical Society, 499(1), 40-51. doi:10.1093/mnras/staa2802
• Matsuyama, I., Hay, H. C., & Trinh, A. (2020). Powering the Galilean Satellites with Moon‐Moon Tides. Geophysical Research Letters, 47(15). doi:10.1029/2020gl088317
• Matsuyama, I., Schenk, P., & Nimmo, F. (2020). A Very Young Age for True Polar Wander on Europa From Related Fracturing. Geophysical Research Letters, 47(17). doi:10.1029/2020gl088364
• Schenk, P., Matsuyama, I., & Nimmo, F. (2020). A Very Young Age for True Polar Wander on Europa From Related Fracturing. Geophysical Research Letters, 47(17), e88364.
• Bouley, S., Keane, J., Baratoux, D., Langlais, B., Matsuyama, I., Costard, F., Hewins, R., Sautter, V., S{\'ejourn\'e}, A., Vanderhaeghe, O., & Zanda, B. (2019). Structure of the Martian Highlands Without Impact Basins and Volcanoes. LPI Contributions, 2089, 6014.
• Cruikshank, D. P., Umurhan, O. M., Beyer, R. A., Schmitt, B., Keane, J. T., Runyon, K. D., Atri, D., White, O. L., Matsuyama, I., Moore, J. M., McKinnon, W. B., {Sand, f., Singer, K. N., Grundy, W. M., Dalle, O., Cook, J. C., Bertrand, T., Stern, S. A., Olkin, C. B., , Weaver, H. A., et al. (2019). Recent cryovolcanism in Virgil Fossae on Pluto. Icarus, 330, 155-168.
• Hay, H. C., & Matsuyama, I. (2019). Nonlinear tidal dissipation in the subsurface oceans of Enceladus and other icy satellites. Icarus, 319, 68--85.
• Hay, H. C., & Matsuyama, I. (2019). Tides Between the TRAPPIST-1 Planets. The Astrophysical Journal, 875(1), 22.
• Nimmo, F., & Matsuyama, I. (2019). Tidal dissipation in rubble-pile asteroids. Icarus, 321, 715--721.
• Matsuyama, I. M., Beuthe, M., Hay, H. C., & Nimmo, F. (2018). Ocean tidal heating in icy satellites with solid shells. Icarus, 312, 208-230. doi:10.1016/j.icarus.2018.04.013
• Hay, H. C., & Matsuyama, I. M. (2017). Numerically Simulating Ocean Dissipation in the Icy Satellites. Icarus.
• Hemingway, D., & Matsuyama, I. (2017). Isostatic equilibrium in spherical coordinates and implications for crustal thickness on the Moon, Mars, Enceladus, and elsewhere. Geophysical Research Letters, 44, 7695-7705.
• Keane, J., & Matsuyama, I. (2017). Reorientation Histories of Mercury, Venus, the Moon, and Mars. European Planetary Science Congress, 11, EPSC2017-415.
• Matsuyama, I., & Hemingway, D. J. (2017). Isostatic equilibrium in spherical coordinates and implications for crustal thickness on the Moon, Mars, Enceladus, and elsewhere: ISOSTASY ON A SPHERE. Geophysical Research Letters, 44(15), 7695-7705. doi:10.1002/2017gl073334
• Bouley, S., Baratoux, D., Matsuyama, I., Froget, F., Séjourné, A., Turbet, M., & Costard, F. (2016). Late Tharsis Formation and implications for Early Mars. Nature.
• Keane, J. T., Matsuyama, I. M., Kamata, S., & Steckloff, J. K. (2016). Reorientation of Pluto due to the formation and evolution of Sputnik Planum.. Nature.
• Matsuyama, I. M., Nimmo, F., Keane, J. T., Chan, N. H., Taylor, G. J., Kiefer, W. S., & Williams, J. G. (2016). GRAIL, LLR, and LOLA constraints on the interior structure of the Moon. Geophysical Research Letters, 43, 8365–8375. doi:10.1002/2016GL069952
• Matsuyama, I., Nimmo, F., Keane, J. T., Chan, N. H., Taylor, G. J., Wieczorek, M. A., Kiefer, W. S., & Williams, J. G. (2016). GRAIL, LLR, and LOLA constraints on the interior structure of the Moon. Geophysical Research Letters, 43(16), 8365-8375. doi:10.1002/2016gl069952
• Siegler, M. A., Miller, R. S., Keane, J. T., Laneuville, M., Paige, D. A., Matsuyama, I., Lawerence, D. J., Crotts, A., & Boston, M. J. (2016). Lunar True Polar Wander Inferred from Polar Hydrogen. Nature.
• Zuber, M. T., Smith, D. E., Neumann, G. A., Goossens, S., Andrews-Hanna, J. C., Head, J. W., Kiefer, W. S., Asmar, S. W., Konopliv, A. S., Lemoine, F. G., Matsuyama, I., Melosh, H. J., McGovern, P. J., Nimmo, F., Phillips, R. J., Solomon, S. C., Taylor, G. J., Watkins, M. M., Wieczorek, M. A., , Williams, J. G., et al. (2016). Gravity field of the Orientale basin from the Gravity Recovery and Interior Laboratory Mission. Science, 354, 438-441.
• Kamata, S., Matsuyama, I., & Nimmo, F. (2015). Tidal resonance in icy satellites with subsurface oceans. Journal of Geophysical Research (Planets), 120, 1528-1542.
• Matsuyama, I., Kamata, S., & Nimmo, F. (2015). Tidal resonance in icy satellites with subsurface oceans: TIDAL RESONANCE IN ICY SATELLITES. Journal of Geophysical Research: Planets, 120(9), 1528-1542. doi:10.1002/2015je004821
• Chan, N., Mitrovica, J. X., Matsuyama, I. M., Daradich, A., Stanley, S., & Creveling, J. R. (2014). Time-dependent rotational stability of dynamic planets with elastic lithospheres. Journal of Geophysical Research (Planets), 119, 169-188.
• Keane, J. T., & Matsuyama, I. (2014). Evidence for lunar true polar wander and a past low-eccentricity, synchronous lunar orbit. Geophysical Research Letters, 41, 6610-6619.
• Matsuyama, I. M. (2014). Tidal dissipation in the oceans of icy satellites. Icarus, 242, 11-18.
• Matsuyama, I. M., Nimmo, F., & Mitrovica, J. X. (2014). Planetary Reorientation. Annual Review of Earth and Planetary Sciences, 42, 605-634.
• Matsuyama, I., & Keane, J. T. (2014). Evidence for lunar true polar wander and a past low-eccentricity, synchronous lunar orbit: The Origin of the Lunar Figure. Geophysical Research Letters, 41(19), 6610-6619. doi:10.1002/2014gl061195
• Matsuyama, I., Nimmo, F., & Mitrovica, J. X. (2014). Planetary Reorientation. Annual Review of Earth and Planetary Sciences, 42(1), 605-634. doi:10.1146/annurev-earth-060313-054724
• Matsuyama, I., Williams, J. G., Konopliv, A. S., Boggs, D. H., Park, R. S., Yuan, D., Lemoine, F. G., Goossens, S., Mazarico, E., Nimmo, F., Weber, R. C., Asmar, S. W., Melosh, H. J., Neumann, G. A., Phillips, R. J., Smith, D. E., Solomon, S. C., Watkins, M. M., Wieczorek, M. A., , Andrews-Hanna, J. C., et al. (2014). Lunar interior properties from the GRAIL mission: Lunar Interior Properties. Journal of Geophysical Research: Planets, 119(7), 1546-1578. doi:10.1002/2013je004559
• Williams, J. G., Konopliv, A. S., Boggs, D. H., Park, R. S., Yuan, D., Lemoine, F. G., Goossens, S., Mazarico, E., Nimmo, F., Matsuyama, I. M., Weber, R. C., Asmar, S. W., Melosh, H. J., Neumann, G. A., Phillips, R. J., Smith, D. E., Solomon, S. C., Watkins, M. M., Wieczorek, M. A., , Andrews-Hanna, J. C., et al. (2014). Lunar interior properties from the GRAIL mission. Journal of Geophysical Research (Planets), 119, 1546-1578.
• Andrews-Hanna, J. C., Asmar, S. W., W., J., Kiefer, W. S., Konopliv, A. S., Lemoine, F. G., Matsuyama, I., Mazarico, E., McGovern, P. J., Melosh, H. J., Neumann, G. A., Nimmo, F., Phillips, R. J., Smith, D. E., Solomon, S. C., Taylor, G. J., Wieczorek, M. A., Williams, J. G., & Zuber, M. T. (2013). Ancient igneous intrusions and early expansion of the moon revealed by GRAIL gravity gradiometry. Science, 339(6120), 675-678.
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  PMID: 23223393;Abstract: The earliest history of the Moon is poorly preserved in the surface geologic record due to the high flux of impactors, but aspects of that history may be preserved in subsurface structures. Application of gravity gradiometry to observations by the Gravity Recovery and Interior Laboratory (GRAIL) mission results in the identification of a population of linear gravity anomalies with lengths of hundreds of kilometers. Inversion of the gravity anomalies indicates elongated positive-density anomalies that are interpreted to be ancient vertical tabular intrusions or dikes formed by magmatism in combination with extension of the lithosphere. Crosscutting relationships support a pre-Nectarian to Nectarian age, preceding the end of the heavy bombardment of the Moon. The distribution, orientation, and dimensions of the intrusions indicate a globally isotropic extensional stress state arising from an increase in the Moon's radius by 0.6 to 4.9 kilometers early in lunar history, consistent with predictions of thermal models.
• Matsuyama, I. (2013). Fossil figure contribution to the lunar figure. Icarus, 222(1), 411-414.
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  Abstract: The unusual shape of the Moon given its present rotational and orbital state has been explained as due to a fossil figure preserving a record of remnant rotational and tidal deformation (Jeffreys, H. [1915]. Mem. R. Astron. Soc. 60, 187-217; Lambeck, K., Pullan, S. [1980]. Phys. Earth Planet. Interiors 22, 29-35; Garrick-Bethell, I., Wisdom, J., Zuber, M.T. [2006]. Science 313, 652-655). However, previous studies assume infinite rigidity and ignore deformation due to changes in the rotational and orbital potentials as the Moon evolves to the present state. We interpret the global lunar figure with a physical model that takes into account this deformation. Although the Moon deforms in response to rotational and orbital changes, a fossil figure capable of explaining the observed figure can be preserved by an elastic lithosphere. © 2012 Elsevier Inc.
• Matsuyama, I., Andrews-Hanna, J. C., Asmar, S. W., Head, J. W., Kiefer, W. S., Konopliv, A. S., Lemoine, F. G., Mazarico, E., McGovern, P. J., Melosh, H. J., Neumann, G. A., Nimmo, F., Phillips, R. J., Smith, D. E., Solomon, S. C., Taylor, G. J., Wieczorek, M. A., Williams, J. G., & Zuber, M. T. (2013). Ancient Igneous Intrusions and Early Expansion of the Moon Revealed by GRAIL Gravity Gradiometry. Science, 339(6120), 675-678. doi:10.1126/science.1231753
• Creveling, J. R., Mitrovica, J. X., Chan, N. -., Latychev, K., & Matsuyama, I. (2012). Mechanisms for oscillatory true polar wander. Nature, 491(7423), 244-248.
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  PMID: 23135471;Abstract: Palaeomagnetic studies of Palaeoproterozoic to Cretaceous rocks propose a suite of large and relatively rapid (tens of degrees over 10 to 100 million years) excursions of the rotation pole relative to the surface geography, or true polar wander (TPW). These excursions may be linked in an oscillatory, approximately coaxial succession about the centre of the contemporaneous supercontinent. Within the framework of a standard rotational theory, in which a delayed viscous adjustment of the rotational bulge acts to stabilize the rotation axis, geodynamic models for oscillatory TPW generally appeal to consecutive, opposite loading phases of comparable magnitude. Here we extend a nonlinear rotational stability theory to incorporate the stabilizing effect of TPW-induced elastic stresses in the lithosphere. We demonstrate that convectively driven inertia perturbations acting on a nearly prolate, non-hydrostatic Earth with an effective elastic lithospheric thickness of about 10 kilometres yield oscillatory TPW paths consistent with palaeomagnetic inferences. This estimate of elastic thickness can be reduced, even to zero, if the rotation axis is stabilized by long-term excess ellipticity in the plane of the TPW. We speculate that these sources of stabilization, acting on TPW driven by a time-varying mantle flow field, provide a mechanism for linking the distinct, oscillatory TPW events of the past few billion years. © 2012 Macmillan Publishers Limited. All rights reserved.
• Chan, N. -., Mitrovica, J. X., Matsuyama, I., Creveling, J. R., & Stanley, S. (2011). The rotational stability of a convecting earth: Assessing inferences of rapid TPW in the late cretaceous. Geophysical Journal International, 187(3), 1319-1333.
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  Abstract: We outline a linearized rotational stability theory for predicting the time dependence of true polar wander (TPW) on a Maxwell viscoelastic body in response to mantle convective loading. The new theory is based on recent advances in ice age rotation theory. A comparison between predictions based on the new theory and analytic expressions for equilibrium (infinite-time) TPW on planetary models with elastic lithospheres demonstrates that the linearized theory can, in the case of loading at mid-latitudes, predict TPW of over 20° to better than 5 per cent accuracy. We present predictions of TPW for loading with periodic and net ramp-up time histories. Moreover, we compare the time dependence of TPW under assumptions consistent with the canonical equilibrium stability theory adopted in most previous analyses of convection-induced TPW, and a stability theory that includes two effects that have not been considered in previous geophysical analyses: (1) the so-called 'remnant rotational bulge' associated with the imperfect reorientation of the rotational bulge due to the presence of an elastic lithosphere; and (2) a stable (over the timescale of the forcing) excess ellipticity. As a first application of the new theory, we consider recent inferences of rapid (order 1 Myr) TPW motion of amplitude 10°-20° during the Late Cretaceous. We conclude that excursions of this amplitude and timescale are physically implausible. © 2011 The Authors Geophysical Journal International © 2011 RAS.
• Chan, N. -., Mitrovica, J. X., Matsuyama, I., Latychev, K., Creveling, J. R., Stanley, S., & Morrow, E. (2011). The rotational stability of a convecting Earth: The Earth's figure and TPW over the last 100 Myr. Geophysical Journal International, 187(2), 773-782.
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  Abstract: Palaeomagnetic records spanning the last 100 Myr indicate that the reorientation of the Earth's rotation axis relative to the surface geography (or true polar wander, TPW) has been confined to a range less than 6° from its present location. This limited TPW is unexpected given that a canonical theory for the rotational stability of the Earth generally predicts that mantle convection should drive larger displacements of the pole. We argue, following earlier work, that the muted TPW is a consequence of the stable, excess flattening of the Earth's figure driven by plate subduction and deep mantle superplumes rising beneath Africa and the Pacific. In particular, we show that the TPW record is consistent with convection-induced perturbations to the Earth's inertia tensor of order 20 per cent or less of the excess flattening over the last 100 Myr; this upper bound will be higher if the Earth's lithosphere retains any significant elastic strength over such long timescales. This inferred stability of the Earth's figure has important implications for our understanding of deep mantle structure and the long-term, global-scale evolution of the Earth. © 2011 The Authors Geophysical Journal International © 2011 RAS.
• Matsuyama, I., & Nimmo, F. (2011). Reorientation of Vesta: Gravity and tectonic predictions. Geophysical Research Letters, 38(14).
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  Abstract: Vesta's large southern hemisphere impact basin is likely to have caused reorientation. However, because the basin is not centred at the south pole, Vesta likely also has a remnant rotational figure. Reorientation of 6 is predicted to have occurred based on the dimensions of the basin. Existing measurements of Vesta's shape are consistent with 20 or less reorientation, and 20% or less despinning. Both the remnant rotational figure and the basin contribute to the degree-2 gravity coefficients, which will be measured by the Dawn mission and will provide a test of the reorientation hypothesis. Reorientation and despinning also give rise to stresses. Vesta's stress state is likely to be dominated by isotropic contraction due to cooling (which does not affect the gravity coefficients). However, the orientation of the resulting thrust features will be controlled by the amount of reorientation and despinning, providing another observational test. Copyright 2011 by the American Geophysical Union.
• Matsuyama, I. (2010). Dispersal of protoplanetary disks by wind stripping. EAS Publications Series, 41, 171-175.
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  Abstract: We present a model for the dispersal of protoplanetary disks by winds from either the central star or the inner disk. These winds obliquely strike the flaring disk surface and strip away disk material by entraining it in an outward radial-moving flow at the disk-wind interface. This interface lies several disk scale heights above the mid plane. The disk dispersal time depends on the velocity at which disk material flows into the mixing layer. If this velocity is ∼10% of the sound speed, the disk dispersal time at ∼1-10 AU is ∼ 5, for a 0.01,M disk around a solar mass star, with a spherical wind launched from the inner disk or central star with a typical mass loss rate of 10 8, and terminal velocity of v {w}=100\,{-1}. We conclude that wind stripping is not a dominant disk dispersal mechanism compared with viscous accretion and photoevaporation. Nevertheless, wind stripping may affect the evolution of the intermediate disk regions. © EAS, EDP Sciences, 2010.
• Matsuyama, I., & Bills, B. G. (2010). Global contraction of planetary bodies due to despinning: Application to Mercury and Iapetus. Icarus, 209(2), 271-279.
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  Abstract: We extend previous work on the global tectonic patterns generated by despinning with a self-consistent treatment of the isotropic despinning contraction that has been ignored. We provide simple analytic approximations that quantify the effect of the isotropic despinning contraction on the global shape and tectonic pattern. The isotropic despinning contraction of Mercury is ∼93m (T/1day)-2, where T is the initial rotation period. If we take into account both the isotropic contraction and the degree-2 deformations associated with despinning, the preponderance of compressional tectonic features on Mercury's surface requires an additional isotropic contraction ≳1km (T/1day)-2, presumably due to cooling of the interior and growth of the solid inner core. The isotropic despinning contraction of Iapetus is ∼9m (T/16h)-2, and it is not sensitive to the presence of a core or the thickness of the elastic lithosphere. The tectonic pattern expected for despinning, including the isotropic contraction, does not explain Iapetus' ridge. Furthermore, the ridge remains unexplained with the addition of any isotropic compressional stresses, including those generating by cooling. © 2010 Elsevier Inc.
• Matsuyama, I., & Manga, M. (2010). Mars without the equilibrium rotational figure, Tharsis, and the remnant rotational figure. Journal of Geophysical Research E: Planets, 115(12).
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  Abstract: We use a revised partitioning of the planet figure into equilibrium and nonequilibrium contributions that takes into account the presence of an elastic lithosphere to study the Martian gravity field and shape. The equilibrium contribution is associated with the present rotational figure, and the nonequilibrium contribution is dominated by Tharsis and a remnant rotational figure supported by the elastic lithosphere that traces the paleopole location prior to the formation of Tharsis. We calculate the probability density functions for Tharsis' size and location, the paleopole location, and the global average thickness of the elastic lithosphere at the time Tharsis was emplaced. Given the observed degree-3 spherical harmonic gravity coefficients, the expected Tharsis center location is 258.6 ± 4.2°E, 9.8 ± 0.9°N, where the uncertainties represent the 90% confidence interval. Given this Tharsis center location and the observed degree-2 spherical harmonic gravity coefficients, the expected paleopole location prior to the emplacement of Tharsis is 259.5 ± 49.5°E, 71.1-14.4+17.5°N, and the expected elastic lithospheric thickness at the time of loading is 58-32+34 km. Our estimated paleopole colatitude implies 18.9-17.5+14.4° of true polar wander (TPW) driven by the emplacement of Tharsis, in disagreement with previous studies that invoke large TPW. The remnant rotational figure is visible in both the nonequilibrium degree-2 geoid (areoid) without Tharsis and the nonequilibrium degree-2 topography without Tharsis. The remnant rotational figure is also visible in the total nonequilibrium geoid without Tharsis, but it is not visible in the total nonequilibrium topography without Tharsis due to the strong signal of the north-south dichotomy. Shorter wavelength geological features become significantly more visible in the geoid with the removal of the long wavelength contributions of the equilibrium rotational figure, Tharsis, and the remnant rotational figure. Removal of the equilibrium rotational figure and Tharsis from the topography reveals a better defined north-south dichotomy boundary. Copyright 2010 by the American Geophysical Union.
• Matsuyama, I., Mitrovica, J. X., Daradich, A., & Gomez, N. (2010). The rotational stability of a triaxial ice-age Earth. Journal of Geophysical Research B: Solid Earth, 115(5).
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  Abstract: Mitrovica et al. (2005), following calculations by Nakada (2002), demonstrated that the traditional approach for computing rotation perturbations driven by glacial isostatic adjustment significantly overestimates present-day true polar wander (TPW) speeds by underestimating the background oblateness on which the ice-age loading is superimposed. The underestimation has two contributions: the first originates from the treatment of the hydrostatic form and the second from the neglect of the Earth?s excess ellipticity supported by mantle convection. In Mitrovica et al. (2005), the second of these two contributions was computed assuming a biaxial nonhydrostatic form (i.e., the principal equatorial moments of inertia were assumed to be equal to their mean value). In this article we outline an extended approach that accounts for a triaxial planetary form. We show that differences in the TPW speed predicted using the Mitrovica et al. (2005) approach and our triaxial theory are relatively minor (∼0.1°/Myr) and are limited to Earth models with lower mantle viscosity less than ∼5 × 1021 Pa s. However, for this same class of Earth models, the angle of TPW predicted for a triaxial Earth is rotated westward (toward the axis of maximum equatorial inertia) by as much as ∼20° relative to the biaxial case. We demonstrate that these effects are a consequence of the geometry of the ice-age forcing, which has a dominant equatorial direction that is intermediate to the axes defining the principal equatorial moments of inertia of the planet. We complete the study by computing updated Frechet kernels for the TPW speed datum, which provide a measure of the detailed depth-dependent sensitivity of the predictions to variations in mantle viscosity. We show, in contrast to earlier efforts to explore this sensitivity based on the traditional rotation theory, that the datum does not generally have a sensitivity to viscosity that peaks near the base of the mantle. Copyright 2010 by the American Geophysical Union.
• Vicente, S., Alves, J., Matsuyama, I., Bouy, H., Spezzi, L., Ascenso, J., Santos, F. D., & Prusti, T. (2010). VLT/NACO detection of a proplyd/jet candidate in the core of Trumpler 14. Proceedings of the International Astronomical Union, 6(S275), 412-413.
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  Abstract: This paper reports the discovery and presents the results of a first analysis of the observed morphology of a candidate external irradiated circumstellar disk/jet system found in the deep core of Trumpler 14, a cluster an order of magnitude more massive than the only cluster where bona-fide proplyds have been found, the Trapezium cluster in the Orion Nebula. © International Astronomical Union 2011.
• Kite, E. S., Matsuyama, I., Manga, M., Perron, J. T., & Mitrovica, J. X. (2009). True Polar Wander driven by late-stage volcanism and the distribution of paleopolar deposits on Mars. Earth and Planetary Science Letters, 280(1-4), 254-267.
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  Abstract: The areal centroids of the youngest polar deposits on Mars are offset from those of adjacent paleopolar deposits by 5-10°. We test the hypothesis that the offset is the result of True Polar Wander (TPW), the motion of the solid surface with respect to the spin axis, caused by a mass redistribution within or on the surface of Mars. In particular, we consider the possibility that TPW is driven by late-stage volcanism during the Late Hesperian to Amazonian. There is observational and qualitative support for this hypothesis: in both north and south, observed offsets lie close to a great circle 90° from Tharsis, as expected for polar wander after Tharsis formed. We calculate the magnitude and direction of TPW produced by mapped late-stage lavas for a range of lithospheric thicknesses, lava thicknesses, eruption histories, and prior polar wander events. We find that if Tharsis formed close to the equator, the stabilizing effect of a fossil rotational bulge located close to the equator leads to predicted TPW of < 2°, too small to account for observed offsets. If, however, Tharsis formed far from the equator, late-stage TPW driven by low-latitude, late-stage volcanism would be 6-33°, similar to that inferred from the location of paleopolar deposits. A volume of 4.4 ± 1.3 × 1019 kg of young erupted lava can account for the offset of the Dorsa Argentea Formation from the present-day south rotation pole. This volume is consistent with prior mapping-based estimates and would imply a mass release of CO2 by volcanic degassing similar to that in the atmosphere at the present time. The South Polar Layered Deposits are offset from the present rotation pole in a direction that is opposite to the other paleopolar deposits. This can be explained by either a sequential eruption of late-stage lavas, or an additional contribution from a plume beneath Elysium. We predict that significant volcanic activity occurred during the time interval represented by the Basal Unit/Planum Boreum unconformity; Planum Boreum postdates the Promethei Lingula Lobe; and that the north polar deposits span a substantial fraction of Solar System history. If the additional contribution to TPW from plumes is small, then we would also predict that Tharsis Montes Formation postdates the Promethei Lingula Lobe of the South Polar Layered Deposits. We conclude with a list of observational tests of the TPW hypothesis. © 2009 Elsevier B.V.
• Matsuyama, I., & Nimmo, F. (2009). Gravity and tectonic patterns of Mercury: Effect of tidal deformation, spin-orbit resonance, nonzero eccentricity, despinning, and reorientation. Journal of Geophysical Research E: Planets, 114(1).
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  Abstract: We consider the effect of spin-orbit resonance, nonzero eccentricity, despinning, and reorientation on Mercury's gravity and tectonic pattern. Large variations of the gravity and shape coefficients from the synchronous rotation and zero eccentricity values, J2/C22 = 10/3 and (b - c)/(a - c) = 1/4, arise because of nonsynchronous rotation and nonzero eccentricity even in the absence of reorientation or despinning. Reorientation or despinning induces additional variations. The large gravity coefficients J2 = (6 ± 2) × 10-5 and C22 = (1 ± 0.5) × 10-5 estimated from the Mariner 10 flybys cannot be attributed to Caloris alone since the required mass excess in this case would have caused Caloris to migrate to one of Mercury's hot poles. Similarly, a large remnant bulge due to a smaller semimajor axis and spin-orbit resonance can be dismissed since the required semimajor axis is unphysically small (
• Matsuyama, I., Johnstone, D., & Hollenbach, D. (2009). Dispersal of Protoplanetary Disks by Central Wind Stripping. The Astrophysical Journal, 700(1), 10-19. doi:10.1088/0004-637x/700/1/10
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  We present a model for the dispersal of protoplanetary disks by winds from either the central star or the inner disk. These winds obliquely strike the flaring disk surface and strip away disk material by entraining it in an outward radial-moving flow at the wind-disk interface, which lies several disk scale heights above the midplane. The disk dispersal time depends on the entrainment velocity, vd = cs , at which disk material flows into this turbulent shear layer interface, where is a scale factor and cs is the local sound speed in the disk surface just below the entrainment layer. If ~ 0.1, a likely upper limit, the dispersal time at 1 AU is ~6 Myr for a disk with a surface density of 103 g cm–2, a solar mass central star, and a wind with an outflow rate and terminal velocity vw = 200kms–1. When compared with photoevaporation and viscous evolution, wind stripping can be a dominant mechanism only for the combination of low accretion rates (10–8 M ☉ yr–1) and wind outflow rates approaching these accretion rates. This case is unusual since generally outflow rates are 0.1 of accretion rates.
• Daradich, A., Mitrovica, J. X., Matsuyama, I., Perron, J. T., Manga, M., & Richards, M. A. (2008). Equilibrium rotational stability and figure of Mars. Icarus, 194(2), 463-475.
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  Abstract: Studies extending over three decades have concluded that the current orientation of the martian rotation pole is unstable. Specifically, the gravitational figure of the planet, after correction for a hydrostatic form, has been interpreted to indicate that the rotation pole should move easily between the present position and a site on the current equator, 90° from the location of the massive Tharsis volcanic province. We demonstrate, using general physical arguments supported by a fluid Love number analysis, that the so-called non-hydrostatic theory is an inaccurate framework for analyzing the rotational stability of planets, such as Mars, that are characterized by long-term elastic strength within the lithosphere. In this case, the appropriate correction to the gravitational figure is the equilibrium rotating form achieved when the elastic lithospheric shell (of some thickness LT) is accounted for. Moreover, the current rotation vector of Mars is shown to be stable when the correct non-equilibrium theory is adopted using values consistent with recent, independent estimates of LT. Finally, we compare observational constraints on the figure of Mars with non-equilibrium predictions based on a large suite of possible Tharsis-driven true polar wander (TPW) scenarios. We conclude, in contrast to recent comparisons of this type based on a non-hydrostatic theory, that the reorientation of the pole associated with the development of Tharsis was likely less than 15° and that the thickness of the elastic lithosphere at the time of Tharsis formation was at least ∼ 50   km. Larger Tharsis-driven TPW is possible if the present-day gravitational form of the planet at degree 2 has significant contributions from non-Tharsis loads; in this case, the most plausible source would be internal heterogeneities linked to convection. © 2007 Elsevier Inc. All rights reserved.
• Matsuyama, I., & Nimmo, F. (2008). Tectonic patterns on reoriented and despun planetary bodies. Icarus, 195(1), 459-473.
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  Abstract: Several processes may produce global tectonic patterns on the surface of a planetary body. The stresses associated with distortions of biaxial figures due to despinning or reorientation were first calculated by Vening Meinesz [Vening Meinesz, F.A., 1947. Trans. Am. Geophys. Union 28 (1), 1-23]. We adopt a mathematically equivalent, but physically more meaningful treatment for distortions associated with rotation. The new approach allows us to find analytic solutions for the general case of stresses associated with distortions of biaxial or triaxial planetary figures. Distortions of biaxial figures may be driven by variations in rotation rate, rotation axis orientation, or the combination of both. Distortions of triaxial figures may be driven by the same mechanisms and/or variations in tidal axis orientation for tidally deformed satellites. While the magnitude of the resulting stresses depends on the adopted elastic and physical parameters, the expected tectonic pattern is independent of these parameters for these mechanisms. Reorientation of the rotation/tidal axis alone is expected to produce normal/thrust faulting provinces enclosing the initial rotation/tidal poles, and thrust/normal faulting provinces enclosing the final rotation/tidal poles. Reorientation of both the rotation and tidal axis results in a wide variety of tectonic patterns for different reorientation geometries. On Europa, the tidal axis reorientation which generally accompanies rotation axis reorientations may provide an alternative explanation for tectonic features that have been interpreted as evidence for non-synchronous rotation. The observed tectonic pattern on Enceladus is more easily explained by a large reorientation (∼90°) of the rotation axis, than by rotation rate variations. © 2007 Elsevier Inc. All rights reserved.
• Schenk, P., Matsuyama, I., & Nimmo, F. (2008). True polar wander on Europa from global-scale small-circle depressions. Nature, 453(7193), 368-371.
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  PMID: 18480819;Abstract: The tectonic patterns and stress history of Europa are exceedingly complex and many large-scale features remain unexplained. True polar wander, involving reorientation of Europa's floating outer ice shell about the tidal axis with Jupiter, has been proposed as a possible explanation for some of the features. This mechanism is possible if the icy shell is latitudinally variable in thickness and decoupled from the rocky interior. It would impose high stress levels on the shell, leading to predictable fracture patterns. No satisfactory match to global-scale features has hitherto been found for polar wander stress patterns. Here we describe broad arcuate troughs and depressions on Europa that do not fit other proposed stress mechanisms in their current position. Using imaging from three spacecraft, we have mapped two global-scale organized concentric antipodal sets of arcuate troughs up to hundreds of kilometres long and 300 m to ∼1.5 km deep. An excellent match to these features is found with stresses caused by an episode of ∼80° true polar wander. These depressions also appear to be geographically related to other large-scale bright and dark lineaments, suggesting that many of Europa's tectonic patterns may also be related to true polar wander. ©2008 Nature Publishing Group.
• Matsuyama, I., & Nimmo, F. (2007). Rotational stability of tidally deformed planetary bodies. Journal of Geophysical Research E: Planets, 112(11).
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  Abstract: We consider the true polar wander (rotational variations driven by mass redistribution) of tidally deformed planetary bodies. The rotation pole of bodies without tidal deformation is stabilized by the component of the rotational bulge which retains a memory for prior rotational states, that is, a remnant rotational bulge. For planetary bodies with tidal deforination, the additional stabilizing effect of a remnant tidal bulge results in less permissive excursions of the rotation pole. The magnitude of the load driving reorientation is parameterized by Q, the ratio between the degree-2 gravitational potential of the load and the remnant rotational bulge. Reorientation is favored if the initial load longitude is close to 90°, that is, close to the center of the leading or trailing hemisphere. As an illustration of the new theory, we consider reorientation driven by internal loading on Saturn's moon Enceladus. Small loads ( Q ≈ 1) are inconsistent with significant reorientation because of the small present-day angular separation between the load and the rotation axis. Larger loads ( Q ≈ 2) permit reorientations approaching 90°. Large reorientation scenarios are consistent with the present-day equatorial location of a geologically inferred ancient polar terrain. Copyright 2007 by the American Geophysical Union.
• Matsuyama, I., Nimmo, F., & Mitrovica, J. X. (2007). Reorientation of planets with lithospheres: The effect of elastic energy. Icarus, 191(2), 401-412.
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  Abstract: It is commonly assumed that internal energy dissipation will ultimately drive planets to principal axis rotation, i.e., where the rotation vector is aligned with the maximum principle axis, since this situation corresponds to the minimum rotational energy state. This assumption simplifies long-term true polar wander (TPW) studies since the rotation pole can then be found by diagonalizing the appropriate (non-equilibrium) inertia tensor. We show that for planets with elastic lithospheres the minimum energy state does not correspond to principal axis rotation. As the planet undergoes reorientation elastic energy is stored in the deforming lithosphere, and the state of minimum total energy is achieved before principal axis rotation. We find solutions for the TPW of planets that include this effect by calculating the elastic stresses associated with deformation, and then minimizing the total (rotational and elastic) energy. These expressions indicate that the stored elastic energy acts to reduce the effective size of the driving load (relative to predictions which do not include this energy term). Our derivation also yields expressions for the TPW-induced stress field that generalizes several earlier results. As an illustration of the new theory, we consider TPW driven by the development of the Tharsis volcanic province on Mars. Once the size of the Tharsis load and the Mars model is specified, the extended theory yields a more limited range on the possible TPW. © 2007 Elsevier Inc. All rights reserved.
• Nimmo, F., & Matsuyama, I. (2007). Reorientation of icy satellites by impact basins. Geophysical Research Letters, 34(19).
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  Abstract: Large impact basins are present on many of the icy satellites of the outer solar system. Assuming that their present-day topography is uncompensated, such basins can cause significant poleward reorientations for slow-rotating satellites, This reorientation may have been accompanied by transient large-amplitude wobble. The largest basins on Tethys, Rhea and Titania are predicted to have caused reorientations of roughly 4°, 7° and 12°, respectively, resulting in global tectonic stresses up to ∼0.5 MPa. The potential anomalies associated with the basins can be up to one-third of those expected for a hydrostatic, tidally-and rotationally-deformed body, and may complicate interpretation of the satellite interior structure. Pluto and Charon, because of their slow rotation, are also likely to have undergone reorientation of 10-20° if they possess impact basins of comparable sizes to those of the Saturnian satellites. Copyright 2007 by the American Geophysical Union.
• Perron, J. T., Mitrovica, J. X., Manga, M., Matsuyama, I., & Richards, M. A. (2007). Evidence for an ancient martian ocean in the topography of deformed shorelines. Nature, 447(7146), 840-843.
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  PMID: 17568743;Abstract: A suite of observations suggests that the northern plains of Mars, which cover nearly one third of the planet's surface, may once have contained an ocean. Perhaps the most provocative evidence for an ancient ocean is a set of surface features that ring the plains for thousands of kilometres and that have been interpreted as a series of palaeoshorelines of different age. It has been shown, however, that topographic profiles along the putative shorelines contain long-wavelength trends with amplitudes of up to several kilometres, and these trends have been taken as an argument against the martian shoreline (and ocean) hypothesis. Here we show that the long-wavelength topography of the shorelines is consistent with deformation caused by true polar wander - a change in the orientation of a planet with respect to its rotation pole - and that the inferred pole path has the geometry expected for a true polar wander event that postdates the formation of the massive Tharsis volcanic rise. ©2007 Nature Publishing Group.
• Matsuyama, I., Mitrovica, J. X., Manga, M., Perron, J. T., & Richards, M. A. (2006). Rotational stability of dynamic planets with elastic lithospheres. Journal of Geophysical Research E: Planets, 111(2).
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  Abstract: We revisit the classic problem of the secular rotational stability of planets in response to loading using the fluid limit of viscoelastic Love number theory. Gold (1955) and Goldreich and Toomre (1969) considered the stability of a hydrostatic planet subject to an uncompensated surface mass load and concluded that a mass of any size would drive true polar wander (TPW) that ultimately reorients the load to the equator. Willemann (1984) treated the more self-consistent problem where the presence of a lithosphere leads to both imperfect load compensation and a remnant rotational bulge. Willemann considered axisymmetric loads and concluded that the equilibrium pole location was governed by a balance, independent of elastic lithospheric thickness, between the load-induced TPW and stabilization by the remnant bulge. Our new analysis demonstrates that the equilibrium pole position is a function of the lithospheric strength, with a convergence to Willemann's results evident at high values of elastic thickness (>400 km for an application to Mars), and significantly larger predicted TPW for planets with thin lithospheres. Furthermore, we demonstrate that nonaxisymmetric surface mass loads and internal (convective) heterogeneity, even when these are small relative to axisymmetric contributions, can profoundly influence the rotational stability. Indeed, we derive the relatively permissive conditions under which nonaxisymmetric forcing initiates an inertial interchange TPW event (i.e., a 90° pole shift). Finally, Willemann's analysis is often cited to argue for a small (
• Mitrovica, J. X., Wahr, J., Matsuyama, I., Paulson, A., & Tamisiea, M. E. (2006). Reanalysis of ancient eclipse, astronomic and geodetic data: A possible route to resolving the enigma of global sea-level rise. Earth and Planetary Science Letters, 243(3-4), 390-399.
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  Abstract: Predictions of the Earth's response to the ice age appear to simultaneously reconcile a set of astronomical, geodetic and ancient eclipse observations related to changes in rotation, thus ruling out ice melting as a major contributor to 20th century sea-level rise. We demonstrate that the reconciliation disappears when an improved theory of rotational stability is applied. Furthermore, our reanalysis of longer satellite records renders previous estimates of the secular change in rotation rate suspect. The updated ice-age predictions and observations permit an anomalous 20th century ice flux of ∼1 mm/yr equivalent sea-level rise. Thus, the full suite of Earth rotation observations are consistent with a connection between climatic warming and recent melting of ice reservoirs. © 2006 Elsevier B.V. All rights reserved.
• Mitrovica, J. X., Wahr, J., Matsuyama, I., & Paulson, A. (2005). The rotational stability of an ice-age earth. Geophysical Journal International, 161(2), 491-506.
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  Abstract: Predictions of glaciation-induced changes in the Earth's rotation vector exhibit sensitivities to Earth structure that are unique within the suite of long-wavelength observables associated with glacial isostatic adjustment (henceforth GIA), and, despite nearly a quarter of a century of research, these sensitivities remain enigmatic. Previous predictions of present-day true polar wander (TPW) speed driven by GIA have indicated, for example, a strong sensitivity to variations in the thickness of the elastic lithosphere and the treatment (phase or chemical?) of the density discontinuity at 670-km depth. Nakada recently presented results that suggest that the predictions are also sensitive to the adopted rheology of the lithosphere; however, his results have introduced an intriguing paradox. In particular, predictions generated using a model with an extremely high-viscosity lithospheric lid do not converge to results for a purely elastic lithosphere of the same thickness. Mitrovica (as cited by Nakada) has suggested that the paradox originates from an inaccuracy in the traditional rotation theory (e.g. Wu & Peltier) associated with the treatment of the background equilibrium rotating form upon which any load- and rotation-induced perturbations are superimposed. We revisit these issues using a new treatment of the linearized Euler equations governing load-induced rotation perturbations on viscoelastic earth models. We demonstrate that our revised theory, in which the background form of the planet combines a hydrostatic component and an observationally inferred excess ellipticity, resolves the apparent paradox. Calculations using the revised theory indicate that earlier predictions based on earth models with purely elastic lithospheric lids are subject to large errors; indeed, previously noted sensitivities of TPW speed predictions to the thickness and rheology (elastic versus viscous) of the lithosphere largely disappear in the application of the new theory. Significant errors are also incurred by neglecting the stabilizing influence of the Earth's excess ellipticity. Finally, we demonstrate that the contribution from rotational feedback on predictions of present-day rates of change of the geoid (sea surface) and crustal velocities are overestimated by the traditional rotation theory, and this has implications for analyses of ongoing satellite (e.g. GRACE) missions and geodetic GPS surveys. © 2005 RAS.
• Johnstone, D., Matsuyama, I., McCarthy, I. G., & Font, A. S. (2004). Destruction of stellar disks by photoevaporation. Revista Mexicana de Astronomia y Astrofisica: Serie de Conferencias, 22, 38-41.
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  Abstract: Photoevaporation may provide an explanation for the short lifetimes of disks around young stars. With the exception of neutral oxygen lines, the observed low-velocity forbidden line emission from T Tauri stars can be reproduced by photoevaporating models. The natural formation of a gap in the disk at several AU due to photoevaporation and viscous spreading provides a possible halting mechanism for migrating planets and an explanation for the abundance of observed planets at these radii.
• Johnstone, D., Matsuyama, I., Mccarthy, I. G., & Font, A. S. (2004). DESTRUCTION OF STELLAR DISKS BY PHOTOEVAPORATION. Revista Mexicana De Astronomia Y Astrofisica, 22, 38-41.
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  Photoevaporation may provide an explanation for the short lifetimes of disks around young stars. With the exception of neutral oxygen lines, the observed low-velocity forbidden line emission from T Tauri stars can be reproduced by photoevaporating models. The natural formation of a gap in the disk at several AU due to photoevaporation and viscous spreading provides a possible halting mechanism for migrating planets and an explanation for the abundance of observed planets at these radii.
• Hogerheijde, M. R., Johnstone, D., Matsuyama, I., Jayawardhana, R., & Muzerolle, J. (2003). Indications for grain growth and mass decrease in cold dust disks around classical T Tauri stars in the MBM 12 young association. Astrophysical Journal Letters, 593(2 II), L101-L104.
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  Abstract: We report the detection of continuum emission at λ = 850 and 450 μm from disks around four classical T Tauri stars in the MBM 12 (L1457) young association. Using a simple model, we infer masses of 0.0014-0.012 M ⊙ for the disk of LkHα 263 ABC, 0.005-0.021 M ⊙ for S18 ABab, 0.03-0.18 M⊙ for LkHα 264 A, and 0.023-0.23 M⊙ for LkHα 262. The disk mass found for LkHα 263 ABC is consistent with the 0.0018 M⊙ inferred from the scattered-light image of the edge-on disk around component C. Comparison to earlier 13CO line observations indicates CO depletion by up to a factor of 300 with respect to dark-cloud values. The spectral energy distributions (SEDs) suggest grain growth, possibly to sizes of a few hundred microns, but our spatially unresolved data cannot rule out opacity as an explanation for the SED shape. Our observations show that these T Tauri stars are still surrounded by significant reservoirs of cold material at an age of 1-5 Myr. We conclude that the observed differences in disk mass are likely explained by binary separation affecting the initial value. With available accretion rate estimates we find that our data are consistent with theoretical expectations for viscously evolving disks having decreased their masses by ∼30%.
• Matsuyama, I., Johnstone, D., & Hartmann, L. (2003). Viscous diffusion and photoevaporation of stellar disks. Astrophysical Journal Letters, 582(2 I), 893-904.
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  Abstract: The evolution of a stellar disk under the influence of viscous evolution, photoevaporation from the central source, and photoevaporation by external stars is studied. We take the typical parameters of T Tauri stars (TTSs) and the Trapezium Cluster conditions. The photoionizing flux from the central source is assumed to arise from both the quiescent star and accretion shocks at the base of stellar magnetospheric columns, along which material from the disk accretes. The accretion flux is calculated self-consistently from the accretion mass-loss rate. We find that the disk cannot be entirely removed using only viscous evolution and photoionization from the disk-star accretion shock. However, when FUV photoevaporation by external massive stars is included, the disk is removed in 106-107 yr, and when EUV photoevaporation by external massive stars is included, the disk is removed in 105-106 yr. An intriguing feature of photoevaporation by the central star is the formation of a gap in the disk at late stages of the disk evolution. As the gap starts forming, viscous spreading and photoevaporation work in resonance. When viscous accretion and photoevaporation by the central star and external massive stars are considered, the disk shrinks and is truncated at the gravitational radius, where it is quickly removed by the combination of viscous accretion, viscous spreading, photoevaporation from the central source, and photoevaporation by the external stars. There is no gap formation for disks nearby external massive stars because the outer annuli are quickly removed by the dominant EUV flux. On the other hand, at larger, more typical distances (d ≫0.03 pc) from the external stars the flux is FUV-dominated. As a consequence, the disk is efficiently evaporated at two different locations, forming a gap during the last stages of the disk evolution.
• Matsuyama, I., Johnstone, D., & Murray, N. (2003). HALTING PLANET MIGRATION BY PHOTOEVAPORATION FROM THE CENTRAL SOURCE. The Astrophysical Journal, 585(2), L143-L146. doi:10.1086/374406
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  The recent discovery of Jupiter mass planets orbiting at a few AU from their stars complements earlier detections of massive planets on very small orbits. The short-period orbits strongly suggest that planet migration has occurred, with the likely mechanism being tidal interactions between the planets and the gas disks out of which they formed. The newly discovered long-period planets, together with the gas giant planets in our solar system, show that migration is either absent or rapidly halted in at least some systems. We propose a mechanism for halting type II migration at several AU in a gas disk. Photoevaporation of the disk by irradiation from the central star can produce a gap in the disk at a few AU, preventing planets outside the gap from migrating down to the star. This would result in an excess of systems with planets at or just outside the photoevaporation radius.
• Matsuyama, I., Johnstone, D., & Murray, N. (2003). Halting planet migration by photoevaporation from the central source. Astrophysical Journal Letters, 585(2 II), L143-L146.
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  Abstract: The recent discovery of Jupiter mass planets orbiting at a few AU from their stars complements earlier detections of massive planets on very small orbits. The short-period orbits strongly suggest that planet migration has occurred, with the likely mechanism being tidal interactions between the planets and the gas disks out of which they formed. The newly discovered long-period planets, together with the gas giant planets in our solar system, show that migration is either absent or rapidly halted in at least some systems. We propose a mechanism for halting type II migration at several AU in a gas disk. Photoevaporation of the disk by irradiation from the central star can produce a gap in the disk at a few AU, preventing planets outside the gap from migrating down to the star. This would result in an excess of systems with planets at or just outside the photoevaporation radius.

Proceedings Publications

• Downey, B., Nimmo, F., & Matsuyama, I. (2022, mar). Evolution of the Lunar Inclination. In 53rd Lunar and Planetary Science Conference, 2678.
• Keane, J., James, P., & Matsuyama, I. (2022, mar). The Moon Without Impact Basins, and the Nature of the South Pole Aitken Basin and the Farside Highlands. In 53rd Lunar and Planetary Science Conference, 2678.
• Rovira-Navarro, M., Matsuyama, I., & Hay, H. C. (2022, sep). A General Formulation of Thin-Shell Tidal Dynamics. In European Planetary Science Congress.
• Schenk, P., Buratti, B., Clark, R., Byrne, P., McKinnon, W., Matsuyama, I., Nimmo, F., & Scipioni, F. (2022, sep). Red Streaks on Tethys: Evidence for Recent Activity. In European Planetary Science Congress.
• Downey, B., Nimmo, F., & Matsuyama, I. (2021, mar). Early Dynamical Evolution of the Moon with a Subsurface Magma Ocean. In 52nd Lunar and Planetary Science Conference.
• Hay, H., Matsuyama, I., & Pappalardo, R. (2021, mar). Can High-Frequency Tidal Deformation Help Constrain the Ocean Thickness of Europa and Ganymede?. In 52nd Lunar and Planetary Science Conference.
• Johnson, P., Keane, J., Young, L., & Matsuyama, I. (2021, oct). Wanderlust on Pluto: Forming Sputnik Planitia with a Coupled True Polar Wander Climate Model. In AAS/Division for Planetary Sciences Meeting Abstracts, 53.
• Keane, J., Ahern, A. A., Bagenal, F., Barr, M., Basu, K. o., Becerra, P., Bertrand, T., Beyer, R. A., Bierson, C. J., Bland, M. T., Breuer, D., Davies, A. G., Kleer, K., Pater, I., DellaGiustina, D. N., Denk, T., Echevarria, A., Elder, C. M., Feaga, L. M., , Grava, C., et al. (2021, may). Recommendations for Addressing Priority Io Science in the Next Decade. In Bulletin of the American Astronomical Society, 53.
• Keane, J., Ahern, A. A., Bagenal, F., Barr, M., Basu, K. o., Becerra, P., Bertrand, T., Beyer, R. A., Bierson, C. J., Bland, M. T., Breuer, D., Davies, A. G., Kleer, K., Pater, I., DellaGiustina, D. N., Denk, T., Echevarria, A., Elder, C. M., Feaga, L. M., , Grava, C., et al. (2021, may). The Science Case for Io Exploration. In Bulletin of the American Astronomical Society, 53.
• Matsuyama, I., & Trinh, A. (2020, may). Gravity constraints on the interior structure of Europa. In EGU General Assembly Conference Abstracts.
• McEwen, A., Kleer, K., Park, R., Bierson, C., Davies, A., DellaGuistina, D., Ermakov, A., Fuller, J., Hamilton, C., Harris, C., Hay, H., Keane, J., Kestay, L., Khurana, K., Kirby, K., Lainey, V., Matsuyama, I., Mandt, K., McCarthy, C., , Nimmo, F., et al. (2020, feb). Tidal Heating: Lessons from Io and the Jovian System; Relevance to Exoplanets. In Exoplanets in Our Backyard: Solar System and Exoplanet Synergies on Planetary Formation, Evolution, and Habitability, 2195.
• Bouley, S., Keane, J., Baratoux, D., Langlais, B., Matsuyama, I., Costard, F., Hewins, R., Sautter, V., S{\'ejourn\'e}, A., Vanderhaeghe, O., & Zanda, B. (2019, Mar). Crustal Structure of Early Mars Without Impact Basins and Volcanoes. In Lunar and Planetary Science Conference.
• Cruikshank, D., Umurhan, O., Beyer, R., Schmitt, B., Keane, J., Runyon, K., Atri, D., White, O., Matsuyama, I., Moore, J., {Sand, f. S., Singer, K., Grundy, W., Dalle, O. C., Cook, J., Bertrand, T., Stern, S., Olkin, C., Weaver, H., , Young, L., et al. (2019, Jul). Cryovolcanism on Pluto. In Pluto System After New Horizons, 2133.
• Hay, H., & Matsuyama, I. (2019, Mar). Nonlinear Tidal Dissipation in Enceladus' Subsurface Ocean and Beyond. In Lunar and Planetary Science Conference.
• Hay, H., & Matsuyama, I. (2019, Mar). Planet-Planet Tidal Heating in the TRAPPIST-1 System. In Lunar and Planetary Science Conference.
• Hay, H., & Matsuyama, I. (2019, May). Ocean-Ice Shell Coupling and Nonlinear Tidal Dissipation in Ocean Worlds. In Ocean Worlds 4, 2168.
• Hay, H., Kleer, K., McEwen, A., Park, R., Bierson, C., Davies, A., DellaGiustina, D., Ermakov, A., Fuller, J., Hamilton, C., Harris, C., Jacobson, R., Keane, J., Kestay, L., Khurana, K., Kirby, K., Lainey, V., Matsuyama, I., McCarthy, C., , Nimmo, F., et al. (2019, May). Tidal Heating: Lessons from Io and the Jovian System (Report from the KISS Workshop). In Ocean Worlds 4, 2168.
• Keane, J., & Matsuyama, I. (2019, Jul). True Polar Wander of Pluto. In Pluto System After New Horizons, 2133.
• Matsuyama, I., Keane, J., Watters, T., & Nimmo, F. (2019, Apr). Global tectonic patterns of the Moon. In EGU General Assembly Conference Abstracts.
• Nimmo, F., & Matsuyama, I. (2019, Mar). Tidal Dissipation in Rubble-Pile Asteroids and Icy Bodies. In Lunar and Planetary Science Conference.
• Park, R., Kleer, K., McEwen, A., Bierson, C., Davies, A., DellaGiustina, D., Ermakov, A., Fuller, J., Hamilton, C., Harris, C., Hay, H., Jacobson, R., Keane, J., Kestay, L., Khurana, K., Kirby, K., Lainey, V., Matsuyama, I., McCarthy, C., , Nimmo, F., et al. (2019, Mar). Tidal Heating: Lessons from Io and the Jovian System (Report from the KISS Workshop). In Lunar and Planetary Science Conference.
• Trinh, A., Beuthe, M., & Matsuyama, I. (2019, Sep). A comparison between physical and classical prescriptions of isostasy. In EPSC-DPS Joint Meeting 2019, 2019.
• Hay, H., & Matsuyama, I. (2018). Tidal Dissipation in Subsurface Oceans: Enceladus and Other Icy Moons. In AGU Fall Meeting Abstracts.
• Hay, H., & Matsuyama, I. (2018, mar). Icy Satellite Subsurface Oceans: Tidal Dynamics, Dissipation, and the Solid Shell. In Lunar and Planetary Science Conference, 49.
• Keane, J., & Matsuyama, I. (2018, may). True Polar Wander of Mercury. In Mercury: Current and Future Science of the Innermost Planet, 2047.
• Keane, J., Johnson, B., Matsuyama, I., & Siegler, M. (2018, apr). New Views of the Moon's Spin. In New Views of the Moon 2 - Asia, 2070.
• Keane, J., Johnson, B., Matsuyama, I., & Siegler, M. (2018, mar). The Tumbling Moon: Rotational Dynamics in the Aftermath of Impact Basin Formation. In Lunar and Planetary Science Conference, 49.
• McCarthy, C., Alfred, M., Kleer, K., Park, R. S., Bierson, C. J., DellaGiustina, D., Khurana, K. K., Davies, A. G., Ermakov, A., Fuller, J., & others, . (2018). How do planetary bodies respond to periodic tidal forcing and how does that influence heat flow and orbital evolution?-Report from the KISS Workshop entitled" Tidal Heating-Lessons from Io and the Jovian System". In AGU Fall Meeting Abstracts.
• Andrews-Hanna, J., Weber, R., Ishihara, Y., Kamata, S., Keane, J., Kiefer, W., Matsuyama, I., Siegler, M., & Warren, P. (2017, may). Structure and Evolution of the Lunar Interior. In New Views of the Moon 2 - Europe, 1988.
• Hay, H., & Matsuyama, I. (2017, oct). Ocean Tidal Dynamics and Dissipation in the Thick Shell Worlds. In AAS/Division for Planetary Sciences Meeting Abstracts \#49, 49.
• Keane, J., & Matsuyama, I. (2017, mar). Reorientation Histories of the Moon, Mercury, Venus, and Mars. In Lunar and Planetary Science Conference, 48.
• Tuttle Keane, J., Johnson, B., Matsuyama, I., & Siegler, M. (2017, oct). The Wibbly-Wobbly Moon: Rotational Dynamics of the Moon After Large Impacts. In AAS/Division for Planetary Sciences Meeting Abstracts \#49, 49.
• Keane, J. T., Matsuyama, I., & Siegler, M. A. (2016). IMPACT-DRIVEN TRUE POLAR WANDER OF THE MOON AND ITS IMPLICATIONS FOR THE LONG-TERM STABILITY OF POLAR VOLATILES. In GSA Annual Meeting.
• Keane, J. T., Matsuyama, I., Kamata, S., & Steckloff, J. K. (2016). PLUTO FOLLOWED ITS HEART: REORIENTATION AND FAULTING OF PLUTO DUE TO VOLATILE LOADING IN SPUTNIK PLANUM. In GSA Annual Meeting.
• {Bouley}, S., {Baratoux}, D., {Matsuyama}, I., {Forget}, F., {S{\'e}journ{\'e}}, A., {Turbet}, M., , F. (2016, apr). Late Tharsis Formation and New Perspesctives for Early Mars. In EGU General Assembly Conference Abstracts, 18.
• {Hay}, H., , I. (2016, mar). Numerically Simulating Ocean Dissipation in the Icy Satellites. In Lunar and Planetary Science Conference, 47.
• {Keane}, J. T., , I. (2016, mar). Pluto Followed Its Heart: True Polar Wander of Pluto Due to the Formation and Evolution of Sputnik Planum. In Lunar and Planetary Science Conference, 47.
• {Keane}, J., {Matsuyama}, I., , M. (2016, may). New Insights into Lunar True Polar Wander. In LPI Contributions, 1911, 6085.
• {Kiefer}, W., {Andrews-Hanna}, J., {Evans}, A., {Head}, J., {Matsuyama}, I., {McGovern}, P., {Nimmo}, F., {Soderblom}, J., {Sori}, M., {Taylor}, G., {Weber}, R., {Wieczorek}, M., {Williams}, J., , M. (2016, may). GRAIL Mission Constraints on the Thermal Structure and Evolution of the Moon. In LPI Contributions, 1911, 6031.
• {Matsuyama}, I., , J. (2016, oct). Cassini State Transitions with a Fossil Figure. In AAS/Division for Planetary Sciences Meeting Abstracts, 48.
• {Matsuyama}, I., {Nimmo}, F., {Keane}, J., {Taylor}, G., {Chan}, N., {Williams}, J., {Wieczorek}, M., , W. (2016, may). GRAIL, LLR, and LOLA Constraints on the Interior Structure of the Moon. In LPI Contributions, 1911, 6002.
• {Tuttle Keane}, J., {Matsuyama}, I., {Kamata}, S., , J. (2016, oct). Pluto followed its heart: reorientation and faulting of Pluto due to volatile loading in Sputnik Planum. In AAS/Division for Planetary Sciences Meeting Abstracts, 48.
• Bouley, S., Baratoux, D., Matsuyama, I., Forget, F., Costard, F., & S'ejourn'e, A. (2015, mar). True Polar Wander Recorded by the Distribution of Martian Valley Networks. In Lunar and Planetary Science Conference, 46, 1887.
• Hay, H. C., & Matsuyama, I. (2015, mar). Numerically Simulating Tidal Dissipation in the Icy Satellites. In Lunar and Planetary Science Conference, 46, 1329.
• Kamata, S., Matsuyama, I., & Nimmo, F. (2015, oct). Tidal resonance in icy satellites with subsurface oceans. In European Planetary Science Congress 2015, held 27 September - 2 October, 2015 in Nantes, France, 10, EPSC2015-834.
• Keane, J. T., & Matsuyama, I. (2015, mar). Cleaning Up Degree-2: The Contribution of Impact Basins and Mascons to the Gravity Fields of the Moon, Mercury, and Other Terrestrial Planets. In Lunar and Planetary Science Conference, 46, 2967.
• Keane, J. T., & Matsuyama, I. (2015, mar). Rejuvenating Asteroids During Planetary Flybys: Applications to (99942) Apophis and Other Near-Earth Asteroids. In Lunar and Planetary Science Conference, 46, 2996.
• Siegler, M. A., Miller, R. S., Keane, J. T., Matsuyama, I., Paige, D. A., Poston, M. J., & Lawrence, D. J. (2015, mar). Hidden in the Neutrons: Physical Evidence for Lunar True Polar Wander. In Lunar and Planetary Science Conference, 46, 2675.
• Zuber, M. T., Smith, D. E., Goossens, S. J., Andrews-Hanna, J. C., Head, J. W., Kiefer, W. S., Asmar, S. W., Konopliv, A. S., Lemoine, F. G., Matsuyama, I., McGovern, P. J., Melosh, H. J., Neumann, G. A., Nimmo, F., Phillips, R. J., Solomon, S. C., Taylor, G. J., Watkins, M. M., Wieczorek, M. A., , Johnson, B. C., et al. (2015, mar). Gravity Field of the Orientale Basin from the Gravity Recovery and Interior Laboratory (GRAIL) Mission. In Lunar and Planetary Science Conference, 46, 1447.
• Keane, J. T., & Matsuyama, I. M. (2014, nov). Rejuvenating NEOs: the Efficiency of Asteroid Resurfacing via Planetary Flybys. In AAS/Division for Planetary Sciences Meeting Abstracts, 46, #403.08.
• Matsuyama, I. M. (2014, nov). Tidal Dissipation in the Oceans of Icy Satellites. In AAS/Division for Planetary Sciences Meeting Abstracts, 46, #405.07.
• Matsuyama, I. M., & Keane, J. (2014, 17-21 March). Hill Slope Failure as a Mechanism to Resurface Asteroids During Planetary Flybys. In 45th Lunar and Planetary Science Conference.
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  LPI Contribution No. 1777
• Matsuyama, I. M., Keane, J., & Matsayuma, I. (2014, 17-21 March). The Contribution of Mascons to the Lunar Figure. In 45th Lunar and Planetary Science Conference.
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  LPI Contribution No. 1777
• {Keane}, J., , I. (2014, dec). "{The Contribution of Impact Basins and Mascons to the Lunar Figure: Evidence for Lunar True Polar Wander, and a Past Low-Eccentricity, Synchronous Lunar Orbit}". In AGU Fall Meeting Abstracts.
• {Matsuyama}, I. (2014, dec). "{Tidal Dissipation in the Oceans of Icy Satellites}". In AGU Fall Meeting Abstracts.
• Keane, J., & Matsuyama, I. M. (2013, Fall). The Contribution of Mascons to the Lunar Figure. In American Geophysical Union.
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  Abstract #P51C-1748
• Keane, J., & Matsuyama, I. M. (2013, oct). Hill Slope Failure as a Mechanism to Resurface Asteroids During Planetary Flybys. In AAS/Division for Planetary Sciences Meeting Abstracts, 45, #301.04.
• Matsuyama, I. M., Matsayuma, I., & Nimmo, F. (2013, March 18-22). Pluto's Tectonic Pattern Predictions. In 44th Lunar and Planetary Science Conference.
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  LPI Contribution No. 1719
• Matsuyama, I. M., Zuber, M., Smith, D., Asmar, S., Knonopliv, A., Lemoine, F., Melosh, J., Neumann, G., Phillips, R., Solomon, S., Watkins, M., Wieczorek, M., Williams, J., Andrws-Hanna, J., Garrick-Bethill, I., Head, J., Keifer, W., Matsayuma, I., & McGovern, P. (2013, March 18-22). Gravity Recovery and Interior Laboratory (GRAIL): Extended Mission and Endgame Status. In 44th Lunar and Planetary Science Conference.
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  LPI Contribution No. 1719
• Matsuyama, I. M., Zuber, M., Smith, D., Asmar, S., Knonopliv, A., Lemoine, F., Melosh, J., Neumann, G., Phillips, R., Solomon, S., Watkins, M., Wieczorek, M., Williams, J., Andrws-Hanna, J., Garrick-Bethill, I., Head, J., Keifer, W., Matsayuma, I., McGovern, P., , Nimmo, F., et al. (2013, Fall). What can be learned about the lunar mantle from the Gravity Recovery and Interior Laboratory (GRAIL)?. In American Geophysical Union.
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  Abstract #G31B-06
• Matsuyama, I. M., & Matsayuma, I. (2012, Fall). Constraints on the deep interior structure of the Moon. In American Geophysical Union.
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  Abstract #G33B-0957
• Matsuyama, I. M., & Matsayuma, I. (2012, March 19-23). Tidal Dissipation in the Subsurface Oceans of Icy Satellites. In 43rd Lunar and Planetary Science Conference.
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  LPI Contribution No. 1659; id.2068

Presentations

• Matsuyama, I. M. (2012, Fall). Lunar and Planetary Laboratory. University of Arizona.