Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data

Abstract

The detection of liquid water by the Mars Advanced Radar for Subsurface and Ionosphere Sounding (MARSIS) at the base of the south polar layered deposits in Ultimi Scopuli has reinvigorated the debate about the origin and stability of liquid water under present-day Martian conditions. To establish the extent of subglacial water in this region, we acquired new data, achieving extended radar coverage over the study area. Here, we present and discuss the results obtained by a new method of analysis of the complete MARSIS dataset, based on signal processing procedures usually applied to terrestrial polar ice sheets. Our results strengthen the claim of the detection of a liquid water body at Ultimi Scopuli and indicate the presence of other wet areas nearby. We suggest that the waters are hypersaline perchlorate brines, known to form at Martian polar regions and thought to survive for an extended period of time on a geological scale at below-eutectic temperatures.

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Fig. 1: Ultimi Scopuli Mars Orbiter Laser Altimeter topographic map and location of MARSIS profiles collected in the region.
Fig. 2: SPLD thickness.
Fig. 3: Data collected outside and inside the bright area.
Fig. 4: Spatial distribution of normalized basal reflectivity and acuity.
Fig. 5: Relative dielectric permittivity map computed by inverting the radar data considering all regions where the number of samples is larger than 100.

Data availability

Data reported in this paper are available through the Zenodo research data repository (https://zenodo.org/record/3948005).

Code availability

The code used to produce the figures and numerical results stated in the text is available from the corresponding author on reasonable request.

References

  1. 1.

    Laskar, J. et al. Long term evolution and chaotic diffusion of the insolation quantities of Mars. Icarus 170, 343–364 (2004).

    ADS  Google Scholar 

  2. 2.

    Murray, B. C., Ward, W. R. & Yeung, S. C. Periodic insolation variations on Mars. Science 180, 638–640 (1973).

    ADS  Google Scholar 

  3. 3.

    Ward, W. R. Large-scale variations in the obliquity of Mars. Science 181, 260–262 (1973).

    ADS  Google Scholar 

  4. 4.

    Ward, W. R. in Mars (eds Kieffer, H. H. et al.) 298–320 (Univ. Arizona Press, 1992).

  5. 5.

    Laskar, J., Levrard, B. & Mustard, J. F. Orbital forcing of the Martian polar layered deposits. Nature 419, 375–377 (2002).

    ADS  Google Scholar 

  6. 6.

    Byrne, S. The polar deposits of Mars. Annu. Rev. Earth Planet. Sci. 37, 535–560 (2009).

    ADS  Google Scholar 

  7. 7.

    Guallini, L. et al. Regional stratigraphy of the south polar layered deposits (Promethei Lingula, Mars): “discontinuity-bounded” units in images and radargrams. Icarus 308, 76–107 (2018).

    ADS  Google Scholar 

  8. 8.

    Smith, I. B. et al. 6th International Conference on Mars Polar Science and Exploration: conference summary and five top questions. Icarus 308, 2–14 (2018).

    ADS  Google Scholar 

  9. 9.

    Phillips, R. J. et al. Mars north polar deposits: stratigraphy, age, and geodynamical response. Science 320, 1182–1185 (2008).

    ADS  Google Scholar 

  10. 10.

    Head, J. W. & Pratt, S. Extensive Hesperian-aged south polar ice sheet on Mars: evidence for massive melting and retreat, and lateral flow and ponding of meltwater. J. Geophys. Res. 106, 12275–12299 (2001).

    ADS  Google Scholar 

  11. 11.

    Fastook, J. L., Head, J. W., Marchant, D. R., Forget, F. & Madeleine, J.-B. Early Mars climate near the Noachian–Hesperian boundary: independent evidence for cold conditions form basal melting of the south polar ice sheet (Dorsa Argentea Formation) and implications for valley network formation. Icarus 219, 25–40 (2012).

    ADS  Google Scholar 

  12. 12.

    Grott, M. et al. Long-term evolution of the Martian crust-mantle system. Space Sci. Rev. 174, 49–111 (2013).

    ADS  Google Scholar 

  13. 13.

    Grima, C. et al. Large asymmetric polar scarps on Planum Australia, Mars: characterization and evolution. Icarus 212, 96–109 (2011).

    ADS  Google Scholar 

  14. 14.

    Guallini, L., Brozzetti, F. & Marinangeli, L. Large-scale deformational systems in the South Polar Layered Deposits (Promethei Lingula, Mars): “soft-sediment” and deep-seated gravitational slope deformations mechanisms. Icarus 220, 821–843 (2012).

    ADS  Google Scholar 

  15. 15.

    Guallini, L. et al. “Unconformity-bounded” stratigraphic units in the South Polar Layered Deposits (Promethei Lingula, Mars). In STRATI 2013 331–335 (Springer, 2014).

  16. 16.

    Wieczorek, M. A. Constraints on the composition of the Martian south polar cap from gravity and topography. Icarus 196, 506–517 (2008).

    ADS  Google Scholar 

  17. 17.

    Fisher, D. A., Hecht, M. H., Kounaves, S. P. & Catling, D. C. A perchlorate brine lubricated deformable bed facilitating flow on the north polar cap of Mars: possible mechanism for water table recharging. J. Geophys. Res. 115, E00E12 (2010).

    ADS  Google Scholar 

  18. 18.

    Sori, M. M. & Bramson, A. M. Water on Mars, with a grain of salt: local heat anomalies are required for basal melting of ice at the south pole today. Geophys. Res. Lett. 46, 1222–1231 (2019).

    ADS  Google Scholar 

  19. 19.

    Hamilton, C. W., Fagents, S. A. & Wilson, L. Explosive lava-water interactions in Elysium Planitia, Mars: geologic and thermodynamic constraints on the formation of the Tartarus Colles cone groups. J. Geophys. Res. 115, E09006 (2010).

    ADS  Google Scholar 

  20. 20.

    Horvath, D. G. & Andrews-Hanna, J. C. The thickness and morphology of a young pyroclastic deposit in Cerberus Palus, Mars: implications for the formation sequence. In 49th Lunar Planet. Sci. Conference Abstract number 2435 (Lunar and Planetary Institute, 2018).

  21. 21.

    Souček, O., Bourgeois, O., Pochat, S. & Guidat, T. A 3 Ga old polythermal ice sheet in Isidis Planitia, Mars: dynamics and thermal regime inferred from numerical modeling. Earth Planet. Sci. Lett. 426, 176–190 (2015).

    ADS  Google Scholar 

  22. 22.

    Siegert, M. J. A 60-year international history of Antarctic subglacial lake exploration. J. Geol. Soc. Lond. 461, 7–21 (2018).

    Google Scholar 

  23. 23.

    Picardi, G. et al. Radar soundings of the subsurface of Mars. Science 310, 1925–1928 (2005).

    ADS  Google Scholar 

  24. 24.

    Clifford, S. M. et al. Depth of the Martian cryosphere: revised estimates and implications for the existence and detection of subpermafrost groundwater. J. Geophys. Res. 115, E07001 (2010).

    ADS  Google Scholar 

  25. 25.

    Lasue, J., Clifford, S. M., Conway, S. J., Mangold, N. & Butcher, F. E. in Volatiles in the Martian Crust 185–246 (Elsevier, 2019).

  26. 26.

    Orosei, R. et al. Radar evidence of subglacial liquid water on Mars. Science 361, 490–493 (2018).

    ADS  Google Scholar 

  27. 27.

    Oswald, G. K. A. & Gogineni, S. P. Recovery of subglacial water extent from Greenland radar survey data. J. Glaciol. 54, 94–106 (2008).

    ADS  Google Scholar 

  28. 28.

    Carter, S. P. et al. Radar-based subglacial lake classification in Antarctica. Geochem. Geophys. Geosys. 8, Q03016 (2007).

    ADS  Google Scholar 

  29. 29.

    Young, D. A., Schroeder, D. M., Blankenship, D. D., Kempf, S. D. & Quartini, E. The distribution of basal water between Antarctic subglacial lakes from radar sounding. Phil. Trans. R. Soc. A 374, 20140297 (2016).

    ADS  Google Scholar 

  30. 30.

    Palmer, S. J. et al. Greenland subglacial lakes detected by radar. Geophys. Res. Lett. 40, 6154–6159 (2013).

    ADS  Google Scholar 

  31. 31.

    Bowling, J. S., Livingstone, S. J., Sole, A. J. & Chu, W. Distribution and dynamics of Greenland subglacial lakes. Nat. Commun. 10, 2810 (2019).

    ADS  Google Scholar 

  32. 32.

    Rutishauer, A. et al. Discovery of a hypersaline subglacial lake complex beneath Devon Ice Cap, Canadian Arctic. Sci. Adv. 4, eaar4353 (2018).

    ADS  Google Scholar 

  33. 33.

    Oswald, G. K., Rezvanbehbahani, S. & Stearns, L. A. Radar evidence of ponded subglacial water in Greenland. J. Glaciol. 64, 711–729 (2018).

    ADS  Google Scholar 

  34. 34.

    Jordan, T. M. et al. A constraint upon the basal water distribution and thermal state of the Greenland Ice Sheet from radar bed echoes. Cryosphere 12, 2831–2854 (2018).

    ADS  Google Scholar 

  35. 35.

    Dowdeswell, J. A. & Siegert, M. J. The physiography of modern Antarctic subglacial lakes. Glob. Planet. Change 35, 221–236 (2003).

    ADS  Google Scholar 

  36. 36.

    Lauro, S. E. et al. Liquid water detection under the south polar layered deposits of Mars—a probabilistic inversion approach. Remote Sens. 11, 2445 (2019).

    ADS  Google Scholar 

  37. 37.

    Hubbard, A., Lawson, W., Anderson, B., Hubbard, B. & Blatter, H. Evidence for subglacial ponding across Taylor Glacier, Dry Valleys, Antarctica. Ann. Glaciol. 39, 79–84 (2004).

    ADS  Google Scholar 

  38. 38.

    Brass, G. W. Stability of brines on Mars. Icarus 42, 20–28 (1980).

    ADS  Google Scholar 

  39. 39.

    Rennó, N. O. et al. Possible physical and thermodynamical evidence for liquid water at the Phoenix landing site. J. Geophys. Res. 114, E00E03 (2009).

    Google Scholar 

  40. 40.

    Hecht, M. H. et al. Detection of perchlorate and soluble chemistry of Martian soil at the Phoenix Lander site. Science 325, 64–67 (2009).

    ADS  Google Scholar 

  41. 41.

    Osterloo, M. M., Anderson, F. S., Hamilton, V. E. & Hynek, B. M. Geologic context of proposed chloride‐bearing materials on Mars. J. Geophys. Res. 115, E10012 (2010).

    ADS  Google Scholar 

  42. 42.

    Hanley, J., Chevrier, V. F., Berget, D. J. & Adams, R. D. Chlorate salts and solutions on Mars. Geophys. Res. Lett. 39, L08201 (2012).

    ADS  Google Scholar 

  43. 43.

    Glavin, D. P. et al. Evidence for perchlorates and the origin of chlorinated hydrocarbons detected by SAM at the Rocknest Aeolian deposit in Gale Crater. J. Geophys. Res. 118, 1955–1973 (2013).

    Google Scholar 

  44. 44.

    Zorzano, M.-P., Mateo-Martí, E., Prieto-Ballesteros, O., Osuna, S. & Renno, N. Stability of liquid saline water on present day Mars. Geophys. Res. Lett. 36, L20201 (2009).

    ADS  Google Scholar 

  45. 45.

    Gough, R. V., Chevrier, V. F. & Tolbert, M. A. Formation of aqueous solutions on Mars via deliquescence of chloride–perchlorate binary mixtures. Earth Planet. Sci. Lett. 393, 73–82 (2014).

    ADS  Google Scholar 

  46. 46.

    Gough, R. V., Chevrier, V. F. & Tolbert, M. A. Formation of liquid water at low temperatures via the deliquescence of calcium chloride: implications for Antarctica and Mars. Planet. Space Sci. 131, 79–87 (2016).

    ADS  Google Scholar 

  47. 47.

    Gough, R. V., Chevrier, V. F., Baustian, K. J., Wise, M. E. & Tolbert, M. A. Laboratory studies of perchlorate phase transitions: support for metastable aqueous perchlorate solutions on Mars. Earth Planet. Sci. Lett. 312, 371–377 (2011).

    ADS  Google Scholar 

  48. 48.

    Primm, K. M., Gough, R. V., Chevrier, V. F. & Tolbert, M. A. Freezing of perchlorate and chloride brines under Mars-relevant conditions. Geochim. Cosmochim. Acta 212, 211–220 (2017).

    ADS  Google Scholar 

  49. 49.

    Primm, K. M., Stillman, D. E. & Michaels, T. I. Investigating the hysteretic behavior of Mars-relevant chlorides. Icarus 342, 113342 (2020).

    Google Scholar 

  50. 50.

    Toner, J. D. & Catling, D. C. Chlorate brines on Mars: implications for the occurrence of liquid water and deliquescence. Earth Planet. Sci. Lett. 497, 161–168 (2018).

    ADS  Google Scholar 

  51. 51.

    Pestova, O. N., Myund, L. A., Khripun, M. K. & Prigaro, A. V. Polythermal study of the systems M(ClO4)2-H2O (M2+ = Mg2+, Ca2+, Sr2+, Ba2+). Russ. J. Appl. Chem. 78, 409–413 (2005).

    Google Scholar 

  52. 52.

    Chevrier, V. F., Hanley, J. & Altheide, T. S. Stability of perchlorate hydrates and their liquid solutions at the Phoenix landing site, Mars. Geophys. Res. Lett. 36, L10202 (2009).

    ADS  Google Scholar 

  53. 53.

    Toner, J. D., Catling, D. C. & Light, B. The formation of supercooled brines, viscous liquids, and low-temperature perchlorate glasses in aqueous solutions relevant to Mars. Icarus 233, 36–47 (2014).

    ADS  Google Scholar 

  54. 54.

    Arnold, N. S., Conway, S. J., Butcher, F. E. & Balme, M. R. Modeled subglacial water flow routing supports localized intrusive heating as a possible cause of basal melting of Mars' south polar ice cap. J. Geophys. Res. 124, 2101–2116 (2019).

    Google Scholar 

  55. 55.

    Willis, I. C., Pope, E. L., Gwendolyn, J. M., Arnold, N. S. & Long, S. Drainage networks, lakes and water fluxes beneath the Antarctic ice sheet. Ann. Glaciol. 57, 96–108 (2016).

    ADS  Google Scholar 

  56. 56.

    Livingstone, S., Clark, C., Woodward, J. & Kingslake, J. Potential subglacial lake locations and meltwater drainage pathways beneath the Antarctic and Greenland ice sheets. Cryosphere 7, 1721–1740 (2013).

    ADS  Google Scholar 

  57. 57.

    Maus, D. et al. Methanogenic archaea can produce methane in deliquescence-driven Mars analog environments. Sci. Rep. 10, 6 (2020).

    ADS  Google Scholar 

  58. 58.

    Stamenković, V., Ward, L. M., Mischna, M. & Fischer, W. W. O2 solubility in Martian near-surface environments and implications for aerobic life. Nat. Geosci. 11, 905–909 (2018).

    ADS  Google Scholar 

  59. 59.

    Cicchetti, A. et al. Observations of Phobos by the Mars Express radar MARSIS: description of the detection techniques and preliminary results. Adv. Space Res. 60, 2289–2302 (2017).

    ADS  Google Scholar 

  60. 60.

    Schroeder, D. M., Blankenship, D. D. & Young, D. A. Evidence for a water system transition beneath Thwaites Glacier, West Antarctica. Proc. Natl Acad. Sci. USA 110, 12225–12228 (2013).

    ADS  Google Scholar 

  61. 61.

    Li, J. et al. Density variations within the south polar layered deposits of Mars. J. Geophys. Res. 117, E04006 (2012).

    ADS  Google Scholar 

  62. 62.

    Mouginot, J. et al. MARSIS surface reflectivity of the south residual cap of Mars. Icarus 201, 454–459 (2009).

    ADS  Google Scholar 

  63. 63.

    Lauro, S. E. et al. Dielectric constant estimation of the uppermost Basal Unit layer in the Martian Boreales Scopuli region. Icarus 219, 458–467 (2012).

    ADS  Google Scholar 

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Acknowledgements

This work was supported by the Italian Space Agency (ASI) through contract ASI-INAF 2019–21-HH.0 and, in part, by EU H2020 agreement 776276 Planmap. MARSIS is operating onboard the European Space Agency spacecraft Mars Express. We would like to thank S. E. Beaubien for careful proofreading of the manuscript and improvement of the English.

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S.E.L. and E.P. designed the research, developed the methodology, performed data analysis and wrote the manuscript. G.C., L.G. and A.P.R. developed the geological context and contributed to writing relevant sections of the manuscript. G.C. and E.P. developed and wrote the geochemical discussion. E.M. and B.C. performed data analysis, contributed text and figures, and co-wrote the manuscript. A.C. conducted data pre-processing. F.S. contributed to inverse electromagnetic modelling, to the interpretation of the geophysical data and to writing of the manuscript. M.C. contributed to data acquisition and analysis and discussed ideas. F.D.P. contributed text and figures and discussed ideas. R.N. contributed to data acquisition and analysis. R.O. discussed ideas and co-wrote the manuscript. S.E.L., E.P., G.C., L.G., A.P.R., E.M., B.C., F.S. and R.O. edited and revised the manuscript.

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Correspondence to Elena Pettinelli.

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Lauro, S.E., Pettinelli, E., Caprarelli, G. et al. Multiple subglacial water bodies below the south pole of Mars unveiled by new MARSIS data. Nat Astron (2020). https://doi.org/10.1038/s41550-020-1200-6

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