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Conditions for aeolian transport in the Solar System

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Abstract

Sand dunes, which arise wherever loose sediment is mobilized by winds that exceed threshold speed and grains are sufficiently strong to survive collisions1, are ubiquitous in the Solar System2. However, current threshold theories usually neglect physical processes that become relevant under exotic conditions3,4, and are in disagreement when extrapolated to extraterrestrial planetary bodies5,6,7,8,9. Here we draw on results in contact10, rarefied gas11, statistical12 and adhesion13 mechanics to present a theory for the fluid and impact thresholds of aeolian transport that encompasses the various conditions present in Solar System bodies. Our theoretical predictions are consistent with available experimental threshold observations and indicate that these thresholds strongly depend on local environmental conditions everywhere but Earth. Our results suggest, among other things, that Titan’s dunes are locally sourced4 and that Mars’s high threshold makes its dunes more resistant to motion14. This work highlights the role of dunes in understanding atmospheric dynamics and surface sediment. Further studies are needed to include hitherto neglected and still poorly understood processes.

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Fig. 1: Dunes and the forces that create them.
Fig. 2: Fluid threshold prediction and observations.
Fig. 3: Impact threshold prediction and observations.

Data availability

All data are available in the Supplementary Data files. Source data are provided with this paper.

Code availability

The code used to produce this paper can be accessed at https://doi.org/10.5281/zenodo.6480898.

References

  1. Bagnold, R. A. The Physics of Blown Sand and Desert Dunes (Courier, 1941).

  2. Hayes, A. G. Dunes across the Solar System. Science 360, 960–961 (2018).

    ADS  Article  Google Scholar 

  3. Telfer, M. W. et al. Dunes on Pluto. Science 360, 992–997 (2018).

    ADS  Article  Google Scholar 

  4. Yu, X., Hörst, S. M., He, C., McGuiggan, P. & Crawford, B. Where does Titan sand come from: insight from mechanical properties of Titan sand candidates. J. Geophys. Res. Planets 123, 2310–2321 (2018).

    ADS  Article  Google Scholar 

  5. Kok, J. F. An improved parameterization of wind-blown sand flux on Mars that includes the effect of hysteresis. Geophys. Res. Lett. 37, L12202 (2010).

  6. Pähtz, T. & Durán, O. The cessation threshold of nonsuspended sediment transport across aeolian and fluvial environments. J. Geophys. Res. Earth Surf. 123, 1638–1666 (2018).

    ADS  Article  Google Scholar 

  7. Claudin, P. & Andreotti, B. A scaling law for aeolian dunes on Mars, Venus, Earth, and for subaqueous ripples. Earth Planet. Sci. Lett. 252, 30–44 (2006).

    ADS  Article  Google Scholar 

  8. Shao, Y. & Lu, H. A simple expression for wind erosion threshold friction velocity. J. Geophys. Res. Atmos. 105, 22437–22443 (2000).

    ADS  Article  Google Scholar 

  9. Iversen, J. D. & White, B. R. Saltation threshold on Earth, Mars and Venus. Sedimentology 29, 111–119 (1982).

    ADS  Article  Google Scholar 

  10. Johnson, K. L. Contact Mechanics (Cambridge Univ. Press, 1987).

  11. Loth, E. Compressibility and rarefaction effects on drag of a spherical particle. AIAA J. 46, 2219–2228 (2008).

    ADS  Article  Google Scholar 

  12. Byron Bird, R. Transport phenomena. Appl. Mech. Rev. 55, R1–R4 (2002).

    Article  Google Scholar 

  13. Israelachvili, J. N. Intermolecular and Surface Forces (Academic, 2011).

  14. Ayoub, F. et al. Threshold for sand mobility on Mars calibrated from seasonal variations of sand flux. Nat. Commun. 5, 5096 (2014).

    ADS  Article  Google Scholar 

  15. Wiberg, P. L. & Smith, J. D. Calculations of the critical shear stress for motion of uniform and heterogeneous sediments. Water Resour. Res. 23, 1471–1480 (1987).

    ADS  Article  Google Scholar 

  16. Loth, E. Lift of a spherical particle subject to vorticity and/or spin. AIAA J. 46, 801–809 (2008).

    ADS  Article  Google Scholar 

  17. Anderson, R. S. & Haff, P. K. Simulation of eolian saltation. Science 241, 820–823 (1988).

    ADS  Article  Google Scholar 

  18. Beladjine, D., Ammi, M., Oger, L. & Valance, A. Collision process between an incident bead and a three-dimensional granular packing. Phys. Rev. E 75, 061305 (2007).

    ADS  Article  Google Scholar 

  19. Andreotti, B. A two-species model of aeolian sand transport. J. Fluid Mech. 510, 47–70 (2004).

    ADS  MATH  Article  Google Scholar 

  20. Gondret, P., Lance, M. & Petit, L. Bouncing motion of spherical particles in fluids. Phys. Fluids 14, 643–652 (2002).

    ADS  MATH  Article  Google Scholar 

  21. Pähtz, T. & Durán, O. Unification of aeolian and fluvial sediment transport rate from granular physics. Phys. Rev. Lett. 124, 168001 (2020).

    ADS  Article  Google Scholar 

  22. Durán, O., Claudin, P. & Andreotti, B. On aeolian transport: grain-scale interactions, dynamical mechanisms and scaling laws. Aeolian Res. 3, 243–270 (2011).

    ADS  Article  Google Scholar 

  23. Jerolmack, D. J., Reitz, M. D. & Martin, R. L. Sorting out abrasion in a gypsum dune field. J. Geophys. Res. Earth Surf. 116, F02003 (2011).

  24. Ghadiri, M. & Zhang, Z. Impact attrition of particulate solids. Part 1: A theoretical model of chipping. Chem. Eng. Sci. 57, 3659–3669 (2002).

    Article  Google Scholar 

  25. Crouvi, O., Amit, R., Enzel, Y., Porat, N. & Sandler, A. Sand dunes as a major proximal dust source for late Pleistocene loess in the Negev Desert, Israel. Quat. Res. 70, 275–282 (2008).

    Article  Google Scholar 

  26. Swet, N., Kok, J., Huang, Y., Yizhaq, H. & Katra, I. Low dust generation potential from active sand grains by wind abrasion. J. Geophys. Res. Earth Surf. 125, e2020JF005545 (2020).

    ADS  Article  Google Scholar 

  27. Martin, R. L. & Kok, J. F. Size-independent susceptibility to transport in aeolian saltation. J. Geophys. Res. Earth Surf. 124, 1658–1674 (2019).

    ADS  Article  Google Scholar 

  28. McKenna Neuman, C. & Sanderson, S. Humidity control of particle emissions in aeolian systems. J. Geophys. Res. Earth Surf. 113, F02S14 (2008).

  29. Kok, J. F. & Renno, N. O. Electrostatics in wind-blown sand. Phys. Rev. Lett. 100, 014501 (2008).

    ADS  Article  Google Scholar 

  30. Gladstone, G. R. & Young, L. A. New Horizons observations of the atmosphere of Pluto. Annu. Rev. Earth Planet. Sci. 47, 119–140 (2019).

    ADS  Article  Google Scholar 

  31. Sagan, C. & Chyba, C. Triton’s streaks as windblown dust. Nature 346, 546–548 (1990).

    ADS  Article  Google Scholar 

  32. Burr, D. M. et al. Higher-than-predicted saltation threshold wind speeds on Titan. Nature 517, 60–63 (2015).

    ADS  Article  Google Scholar 

  33. Weitz, C. M. et al. Sand grain sizes and shapes in eolian bedforms at Gale Crater, Mars. Geophys. Res. Lett. 45, 9471–9479 (2018).

    ADS  Article  Google Scholar 

  34. Banfield, D. et al. The atmosphere of Mars as observed by InSight. Nat. Geosci. 13, 190–198 (2020).

  35. Ewing, R. C., Peyret, A.-P. B., Kocurek, G. & Bourke, M. Dune field pattern formation and recent transporting winds in the Olympia Undae Dune Field, north polar region of Mars. J. Geophys. Res. Planets 115, E08005 (2010).

  36. Gunn, A. et al. Circadian rhythm of dune-field activity. Geophys. Res. Lett. 48, e2020GL090924 (2021).

    ADS  Article  Google Scholar 

  37. Guo, J. & Julien, P. Y. Buffer Law and Transitional Roughness Effect in Turbulent Open-Channel Flows Civil Engineering Faculty Publications 5 (Univ. of Nebraska—Lincoln, 2007).

  38. Yu, X., Hörst, S. M., He, C., McGuiggan, P. & Bridges, N. T. Direct measurement of interparticle forces of titan aerosol analogs (‘tholin’) using atomic force microscopy. J. Geophys. Res. Planets 122, 2610–2622 (2017).

    ADS  Article  Google Scholar 

  39. Swann, C., Sherman, D. & Ewing, R. Experimentally-derived thresholds for windblown sand on Mars. Geophys. Res. Lett. 47, e2019GL084484 (2019).

  40. Baas, A. C. & Sherman, D. J. Spatiotemporal variability of aeolian sand transport in a coastal dune environment. J. Coast. Res. 22, 1198–1205 (2006).

    Article  Google Scholar 

  41. Bagnold, R. A. The size-grading of sand by wind. Proc. R. Soc. A 163, 250–264 (1937).

    ADS  Google Scholar 

  42. Burr, D. M. et al. A wind tunnel study of the effect of intermediate density ratio on saltation threshold. Aeolian Res. 45, 100601 (2020).

    Article  Google Scholar 

  43. Chepil, W. Dynamics of wind erosion: II. Initiation of soil movement. Soil Sci. 60, 397 (1945).

    ADS  Article  Google Scholar 

  44. Chepil, W. Properties of soil which influence wind erosion: IV. State of dry aggregate structure. Soil Sci. 72, 387–402 (1951).

    ADS  Article  Google Scholar 

  45. Del Bello, E. et al. Experimental simulations of volcanic ash resuspension by wind under the effects of atmospheric humidity. Sci. Rep. 8, 14509 (2018).

    ADS  Article  Google Scholar 

  46. Dong, Z., Liu, X., Wang, H. & Wang, X. Aeolian sand transport: a wind tunnel model. Sediment. Geol. 161, 71–83 (2003).

    ADS  Article  Google Scholar 

  47. Fletcher, B. The incipient motion of granular materials. J. Phys. D 9, 2471 (1976).

    ADS  Article  Google Scholar 

  48. Greeley, R., Iversen, J., Pollack, J., Udovich, N. & White, B. Wind tunnel studies of Martian aeolian processes. Proc. R. Soc. A 341, 331–360 (1974).

    ADS  Google Scholar 

  49. Greeley, R., White, B., Leach, R., Iversen, J. & Pollack, J. Mars: wind friction speeds for particle movement. Geophys. Res. Lett. 3, 417–420 (1976).

    ADS  Article  Google Scholar 

  50. Greeley, R., Leach, R., White, B., Iversen, J. & Pollack, J. Threshold windspeeds for sand on Mars: wind tunnel simulations. Geophys. Res. Lett. 7, 121–124 (1980).

    ADS  Article  Google Scholar 

  51. Greeley, R. et al. Windblown sand on Venus: preliminary results of laboratory simulations. Icarus 57, 112–124 (1984).

    ADS  Article  Google Scholar 

  52. Hong, C., Xueyong, Z., Chenchen, L., Jiajia, H. & Yongqiu, W. Transport mass of creeping sand grains and their movement velocities. J. Geophys. Res. Atmos. 118, 6374–6382 (2013).

    ADS  Article  Google Scholar 

  53. Horikawa, K. & Shen, H. W. Sand Movement by Wind Action: on the Characteristics of Sand Traps Technical Memorandum 119 (US Beach Erosion Board, 1960).

  54. Iversen, J. D. & Rasmussen, K. R. The effect of surface slope on saltation threshold. Sedimentology 41, 721–728 (1994).

    ADS  Article  Google Scholar 

  55. Iversen, J., Pollack, J. B., Greeley, R. & White, B. R. Saltation threshold on Mars: the effect of interparticle force, surface roughness, and low atmospheric density. Icarus 29, 381–393 (1976).

    ADS  Article  Google Scholar 

  56. Kadib, A. A Function for Sand Movement by Wind Technical Report (Univ. of California, Berkeley, Institute of Engineering Research, 1965).

  57. Li, B. & McKenna Neuman, C. Boundary-layer turbulence characteristics during aeolian saltation. Geophys. Res. Lett. 39, L11402 (2012).

  58. Marshall, J. R. & Greeley, R. An experimental study of aeolian structures on Venus. J. Geophys. Res.: Planets 97, 1007–1016 (1992).

    ADS  Article  Google Scholar 

  59. Martin, R. L. & Kok, J. F. Wind-invariant saltation heights imply linear scaling of aeolian saltation flux with shear stress. Sci. Adv. 3, e1602569 (2017).

    ADS  Article  Google Scholar 

  60. McKenna-Neuman, C. & Nickling, W. A theoretical and wind tunnel investigation of the effect of capillary water on the entrainment of sediment by wind. Can. J. Soil Sci. 69, 79–96 (1989).

    Article  Google Scholar 

  61. Merrison, J., Jensen, J., Kinch, K., Mugford, R. & Nørnberg, P. The electrical properties of Mars analogue dust. Planet. Space Sci. 52, 279–290 (2004).

    ADS  Article  Google Scholar 

  62. Nalpanis, P., Hunt, J. & Barrett, C. Saltating particles over flat beds. J. Fluid Mech. 251, 661–685 (1993).

    ADS  Article  Google Scholar 

  63. Nickling, W. The stabilizing role of bonding agents on the entrainment of sediment by wind. Sedimentology 31, 111–117 (1984).

    ADS  Article  Google Scholar 

  64. Selah, A. & Fryrear, D. Threshold wind velocities of wet soils as affected by wind blown sand. Soil Sci. 160, 304–309 (1995).

    ADS  Article  Google Scholar 

  65. Shao, Y. & Mikami, M. Heterogeneous saltation: theory, observation and comparison. Bound.-Layer Meteorol. 115, 359–379 (2005).

    ADS  Article  Google Scholar 

  66. Svasek, J. & Terwindt, J. Measurements of sand transport by wind on a natural beach. Sedimentology 21, 311–322 (1974).

    ADS  Article  Google Scholar 

  67. Williams, J. J., Butterfield, G. R. & Clark, D. G. Aerodynamic entrainment threshold: effects of boundary layer flow conditions. Sedimentology 41, 309–328 (1994).

    ADS  Article  Google Scholar 

  68. Williams, J. J. Aeolian Entrainment Thresholds in a Developing Boundary Layer. PhD thesis, Queen Mary Univ. of London (1986).

  69. Seiphoori, A., Ma, X.-g., Arratia, P. E. & Jerolmack, D. J. Formation of stable aggregates by fluid-assembled solid bridges. Proc. Natl Acad. Sci. USA 117, 3375–3381 (2020).

    ADS  Article  Google Scholar 

  70. Bergström, L. Hamaker constants of inorganic materials. Adv. Colloid Interface Sci. 70, 125–169 (1997).

    Article  Google Scholar 

  71. Médout-Marère, V. A simple experimental way of measuring the Hamaker constant a11 of divided solids by immersion calorimetry in apolar liquids. J. Colloid Interface Sci. 228, 434–437 (2000).

    ADS  Article  Google Scholar 

  72. Neufeld, P. D., Janzen, A. & Aziz, R. Empirical equations to calculate 16 of the transport collision integrals ω(l, s)* for the Lennard-Jones (12–6) potential. J. Chem. Phys. 57, 1100–1102 (1972).

    ADS  Article  Google Scholar 

  73. Virtanen, P. et al. SciPy 1.0: fundamental algorithms for scientific computing in Python. Nat. Methods 17, 261–272 (2020).

    Article  Google Scholar 

  74. Andreotti, B., Claudin, P. & Pouliquen, O. Measurements of the aeolian sand transport saturation length. Geomorphology 123, 343–348 (2010).

    ADS  Article  Google Scholar 

  75. Andreotti, B., Claudin, P., Iversen, J. J., Merrison, J. P. & Rasmussen, K. R. A lower-than-expected saltation threshold at Martian pressure and below. Proc. Natl Acad. Sci. USA 118, e2012386118 (2021).

    Article  Google Scholar 

  76. Cornelis, W. M., Gabriels, D. & Hartmann, R. A parameterisation for the threshold shear velocity to initiate deflation of dry and wet sediment. Geomorphology 59, 43–51 (2004).

    ADS  Article  Google Scholar 

  77. Iversen, J. D. & Rasmussen, K. R. The effect of wind speed and bed slope on sand transport. Sedimentology 46, 723–731 (1999).

    ADS  Article  Google Scholar 

  78. Jones, J. & Willetts, B. Errors in measuring uniform aeolian sand flow by means of an adjustable trap. Sedimentology 26, 463–468 (1979).

    ADS  Article  Google Scholar 

  79. Li, B., Ellis, J. T. & Sherman, D. J. Estimating the impact threshold for wind-blown sand. J. Coast. Res. 70, 627–632 (2014).

    Article  Google Scholar 

  80. Zingg, A. Wind tunnel studies of the movement of sedimentary material. In Proc. 5th Hydraulic Conference Bulletin Vol. 34, 111–135 (Institute of Hydraulics Iowa City, 1953).

  81. Anderson, R. S. & Haff, P. K. Wind modification and bed response during saltation of sand in air. In Aeolian Grain Transport 1 (eds Barndorff-Nielsen, O.E. & Willetts, B.B.) 21–51 (Springer, 1991).

  82. Charru, F., Mouilleron, H. & Eiff, O. Erosion and deposition of particles on a bed sheared by a viscous flow. J. Fluid Mech. 519, 55–80 (2004).

    ADS  MATH  Article  Google Scholar 

  83. Ferdowsi, B., Ortiz, C. P., Houssais, M. & Jerolmack, D. J. River-bed armouring as a granular segregation phenomenon. Nat. Commun. 8, 1363 (2017).

    ADS  Article  Google Scholar 

  84. Nishimura, K. & Hunt, J. Saltation and incipient suspension above a flat particle bed below a turbulent boundary layer. J. Fluid Mech. 417, 77–102 (2000).

    ADS  MATH  Article  Google Scholar 

  85. Rice, M. A., Willetts, B. B. & McEwan, I. An experimental study of multiple grain-size ejecta produced by collisions of saltating grains with a flat bed. Sedimentology 42, 695–706 (1995).

    ADS  Article  Google Scholar 

  86. Rioual, F., Valance, A. & Bideau, D. Experimental study of the collision process of a grain on a two-dimensional granular bed. Phys. Rev. E 62, 2450 (2000).

    ADS  Article  Google Scholar 

  87. Creyssels, M. et al. Saltating particles in a turbulent boundary layer: experiment and theory. J. Fluid Mech. 625, 47–74 (2009).

    ADS  MATH  Article  Google Scholar 

  88. Werner, B. T. A Physical Model of Wind-Blown Sand Transport. PhD thesis, California Institute of Technology (1987).

  89. Werner, B. & Haff, P. The impact process in aeolian saltation: two-dimensional simulations. Sedimentology 35, 189–196 (1988).

    ADS  Article  Google Scholar 

  90. Gondret, P., Hallouin, E., Lance, M. & Petit, L. Experiments on the motion of a solid sphere toward a wall: from viscous dissipation to elastohydrodynamic bouncing. Phys. Fluids 11, 2803–2805 (1999).

    ADS  MATH  Article  Google Scholar 

  91. Schmeeckle, M. W., Nelson, J. M., Pitlick, J. & Bennett, J. P. Interparticle collision of natural sediment grains in water. Water Resour. Res. 37, 2377–2391 (2001).

    ADS  Article  Google Scholar 

  92. Evans, B. & Goetze, C. The temperature variation of hardness of olivine and its implication for polycrystalline yield stress. J. Geophys. Res. Solid Earth 84, 5505–5524 (1979).

    Article  Google Scholar 

  93. Courtney, T. H. Mechanical Behavior of Materials (Waveland, 2005).

  94. Domokos, G., Jerolmack, D. J., Kun, F. & Török, J. Plato’s cube and the natural geometry of fragmentation. Proc. Natl Acad. Sci. USA 117, 18178–18185 (2020).

    MathSciNet  Article  Google Scholar 

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Acknowledgements

We thank P. Claudin, B. Andreotti, C. Thom, A. Seiphoori and B. Ferdowsi for insightful discussions. D.J.J. acknowledges support from the Army Research Office, grant 569074. Acknowledgement is made to the Donors of the American Chemical Society Petroleum Research Fund for partial support of this research through grant 61536-ND8 to D.J.J.

Author information

Authors and Affiliations

Authors

Contributions

Conceptualization, data curation, formal analysis, investigation, software, validation, visualization, writing—original draft, A.G.; methodology, project administration, writing—review & editing, A.G. and D.J.J.; resources, funding acquisition, supervision, D.J.J.

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Correspondence to Douglas J. Jerolmack.

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Nature Astronomy thanks Ping Wang and Hezi Yizhaq for their contribution to the peer review of this work.

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Extended data

Extended Data Fig. 1 Wind profiles.

(a) Mean horizontal wind speed with elevation for a fixed friction velocity (u* = 0.3 m/s) and grain size (d = 100μm) for the six bodies of interest using the empirical relation in Supplementary Information Text S4. The grain center is denoted with a black line. (b) Dimensionless presentation of (a), where \({u}_{x}^{+}=u/{u}_{* }\) and z+ = zu*/υ.

Extended Data Fig. 2 Fluid threshold prediction comparison to data.

Four methods for predicting the fluid threshold are compared to observed data, where the vertical axis is u*,observed/u*,predicted − 1 (for the labelled prediction) and the horizontal axis is the Galileo number, \({{{\mathcal{G}}}}\). References for the observations are given on the right, where markers with shaded interiors signify experiments not using standard Earth conditions. The correlation coefficient (r2) for each log-log comparison of u*,observed versus is u*,predicted (that is Fig. 2c) is annotated. (a) The prediction in the main text, where A=1. (b) The prediction except \({{{\mathcal{A}}}}\) is a free-parameter. (c) The prediction using the empirical relation of Iversen & White (1982). (d) The prediction using the semiempirical theory of Shao & Lu (2000).

Source data

Extended Data Fig. 3 Fluid threshold prediction comparison to each other.

The relative error between the alternative predictions of Shao & Lu (2000) (S&L) and Iversen & White (1982) (I&W) with the prediction in the main text for the fluid threshold for average conditions on each body. Each sediment candidate is given for (a) Earth, (b) Mars, (c) Titan, (d) Venus, (e) Pluto and (f) Triton.

Extended Data Fig. 4 Restitution mechanics and empirical fit.

References for the observations are given on the bottom right, where markers with shaded interiors signify experiments not using standard Earth conditions or field data, markers with solid interiors signify explicit measurements of the restitution coefficients outside wind tunnels. Magenta and yellow markers are from studies where the restitution coefficient is measured or noted, values for the vertical-axes of markers with other colors are inferred from simulated trajectories. All horizontal-axes are the Galileo number \({{{\mathcal{G}}}}\). (a) The ratio of the ejection to impact velocity of a characteristic saltating grain, that is the restitution coefficient e. (b) The angle the grain impacts the bed, with the theoretical fixed ejection angle denoted (cyan line). (c) The restitution coefficient normalized such that it impacted the bed at a fixed angle (θ = − 10), e10, with the empirical relationship used in the main text relating the two axes (cyan line) (Methods).

Source data

Extended Data Fig. 5 Impact threshold prediction comparison to data.

Four methods for predicting the impact threshold are compared to observed data, where the vertical axis is u*,observed/u*,predicted − 1 (for the labelled prediction) and the horizontal axis is the Galileo number, \({{{\mathcal{G}}}}\). References for the observations are given on the right, where markers with shaded interiors signify experiments not using standard Earth conditions or field data. The correlation coefficient (r2) for each log-log comparison of u*,observed versus is u*,predicted (that is Fig. 3c) is annotated. (a) The prediction in the main text. (b) The prediction using the semiempirical theory of Kok (2010) (note: the vertical axis bounds are extended in the inset to show the full data extent). (c) The prediction using the semiempirical theory of Pähtz & Durán (2018). (d) The prediction using the semiempirical theory of Claudin & Andreotti (2006).

Source data

Extended Data Fig. 6 Impact threshold prediction comparison to each other.

The relative error between the alternative predictions of Kok (2010) (K), Pähtz & Durán (2018) (P&D) and Claudin & Andreotti (2006) (C&A) with the prediction in the main text for the impact threshold for average conditions on each body. Each sediment candidate is given for (a) Earth, (b) Mars, (c) Titan, (d) Venus, (e) Pluto and (f) Triton.

Extended Data Fig. 7 Trajectory analysis example.

(a-c) Each point on the lines with color corresponding to the colorbar on the left are for a trajectory of a 1 mm quartz grain at average Earth conditions leaving the bed with an ejection velocity of v from the horizontal axis. The solid black line denotes the impact threshold friction velocity, while the black dot and the corresponding dashed black lines denote the unique pair of the friction velocity and ejection velocity at the impact threshold. (a) The ratio of the ejection to impact speeds for a trajectory. (b) The impact angle for a trajectory, with the cyan line indicating the ejection angle. (c) The ratio of the ejection to impact speeds for a trajectory, normalized as if the impact angle was fixed (θ = − 10), e10 (Methods). The green line (also in (d)) is the ‘target’ restitution coefficient for this case using the empirical relation found in Extended Data Figure 4c. (d) The minima for each line in (c) plotted against the friction velocity. We define the impact threshold as the intersection of the trend and the green line.

Extended Data Fig. 8 Contrasting trajectory examples.

Trajectories like Extended Data Figure 7c for Basalt grains at average Mars conditions of size (a) d = 1 mm and (b) d = 10μm. The green lines are the ‘target’ restitution coefficient for each case using the empirical relation found in Extended Data Figure 4c. The qualitatively different behavior in the neighborhood of the solution shows how this formulation of the impact threshold loses meaning for small grains. The minima for each successive curve of fixed friction velocity in (a) are close and transition smoothly, and u* and v are not extremely different. This is in contrast with (b), where the minima close to the target restitution rapidly diverges as u* changes, and v is extremely small at the minima relative to u*.

Extended Data Fig. 9 Trajectory diagnostics.

Predictions for the characteristic saltator trajectory at the impact threshold with varying grain diameter for (a) impact speed, (b) impact angle, (c) hop height and (d) hop duration. Bands show the range for different candidate and known sediments on each planetary body (see legends in (c) and (d)) based on known temperature and pressure variability.

Supplementary information

Supplementary Information

Supplementary Sections 1–6, Tables 1–3 and Figs. 1 and 2.

Supplementary Data 1

Fluid threshold measurements. All collated data used in the fluid threshold fit for each measurement (Methods). Additionally, the phrase used to explain the threshold in the literature is given, as is the wind-tunnel name and height. Note that some of the values in this spreadsheet are assumed and not explicitly stated in the paper in which the threshold measurements are reported; see Methods for an explanation of how these are calculated.

Supplementary Data 2

Impact threshold measurements. All collated data used in the impact threshold fit for each measurement (Methods). Additionally, the phrase used to explain the threshold in the literature is given, as is the wind-tunnel name and height. Note that some of the values in this spreadsheet are assumed and not explicitly stated in the paper in which the threshold measurements are reported; see Methods for an explanation of how these are calculated.

Supplementary Data 3

Restitution coefficient measurements. All collated data used in the impact threshold fit for each measurement (Methods). A cell entry of ‘−9999’ denotes a parameter that does not exist for that experiment (wind-tunnel name and height, for example). Note that some of the values in this spreadsheet are assumed and not explicitly stated in the paper in which the measurements are reported; see Methods for an explanation of how these are calculated.

Source data

Source Data Fig. 2

Data for panels bd.

Source Data Fig. 3

Data for panels c and d.

Source Data Extended Data Fig. 2

Data for all panels.

Source Data Extended Data Fig. 4

Data for all panels.

Source Data Extended Data Fig. 5

Data for all panels.

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Gunn, A., Jerolmack, D.J. Conditions for aeolian transport in the Solar System. Nat Astron (2022). https://doi.org/10.1038/s41550-022-01669-0

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