https://www.nature.com/articles/s41550-022-01775-z Skip to main content Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles and JavaScript. Advertisement Advertisement Nature Astronomy * View all journals * Search * My Account Login * Explore content * About the journal * Publish with us * Subscribe * Sign up for alerts * RSS feed 1. nature 2. nature astronomy 3. matters arising 4. article * Matters Arising * Published: 26 September 2022 Explaining Bright Radar Reflections Below The South Pole of Mars Without Liquid Water * D. E. Lalich ORCID: orcid.org/0000-0003-2091-6991^1, * A. G. Hayes^1 & * V. Poggiali ORCID: orcid.org/0000-0003-1053-3225^1 Nature Astronomy (2022)Cite this article * 228 Accesses * 381 Altmetric * Metrics details Subjects * Cryospheric science * Hydrology The Original Article was published on 28 September 2020 Access through your institution Buy or subscribe arising from: S. E. Lauro et al. Nature Astronomy https://doi.org/ 10.1038/s41550-020-1200-6 (2021). This is a preview of subscription content, access via your institution Access options Access through your institution Access through your institution Change institution Buy or subscribe Subscribe to Nature+ Get immediate online access to the entire Nature family of 50+ journals $29.99 monthly Subscribe Subscribe to Journal Get full journal access for 1 year $119.00 only $9.92 per issue Subscribe All prices are NET prices. VAT will be added later in the checkout. Tax calculation will be finalised during checkout. Buy article Get time limited or full article access on ReadCube. $32.00 Buy All prices are NET prices. Additional access options: * Log in * Learn about institutional subscriptions Fig. 1: Schematic diagrams of the three simulated scenarios. [41550_2022_1775_Fig1_HTML] Fig. 2: Comparison between observed and simulated MARSIS echoes. [41550_2022_1775_Fig2_HTML] Fig. 3: Simulated normalized basal echo power as a function of layer thickness. [41550_2022_1775_Fig3_HTML] Data availability MARSIS data is available through the ESA Planetary Science Archive as well as the NASA Planetary Data System. Superframe data is available through the Orosei et al.^2 supplementary material. References 1. Byrne, S. The polar deposits of Mars. Annu. Rev. Earth Planet. Sci. 37, 535-560 (2009). ADS Article Google Scholar 2. Orosei, R. et al. Radar evidence of subglacial liquid water on Mars. Science 361, 490-493 (2018). ADS Article Google Scholar 3. Lauro, S. E. et al. 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Frequency and time domain permittivity measurements on solid CO[2] and solid CO[2]-soil mixtures as Martian soil simulants. J. Geophys. Res. Planets 108, 8029 (2003). ADS Article Google Scholar Download references Acknowledgements This work was funded in part by a NASA Mars Data Analysis grant awarded to D.E.L. Author information Authors and Affiliations 1. Cornell Center for Astrophysics and Space Science, Ithaca, NY, USA D. E. Lalich, A. G. Hayes & V. Poggiali Authors 1. D. E. Lalich View author publications You can also search for this author in PubMed Google Scholar 2. A. G. Hayes View author publications You can also search for this author in PubMed Google Scholar 3. V. Poggiali View author publications You can also search for this author in PubMed Google Scholar Contributions D.E.L. conceptualized the study, performed simulations, and prepared the manuscript. A.G.H. assisted with conceptualization, interpretation, and manuscript preparation. V.P. assisted with simulations, data analysis, and manuscript preparation. Corresponding author Correspondence to D. E. Lalich. Ethics declarations Competing interests The authors declare no competing interests. Peer review Peer review information Nature Astronomy thanks the anonymous reviewers for their contribution to the peer review of this work. Additional information Publisher's note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations. Rights and permissions Reprints and Permissions About this article Verify currency and authenticity via CrossMark Cite this article Lalich, D.E., Hayes, A.G. & Poggiali, V. Explaining Bright Radar Reflections Below The South Pole of Mars Without Liquid Water. Nat Astron (2022). https://doi.org/10.1038/s41550-022-01775-z Download citation * Received: 17 May 2021 * Accepted: 28 July 2022 * Published: 26 September 2022 * DOI: https://doi.org/10.1038/s41550-022-01775-z Share this article Anyone you share the following link with will be able to read this content: Get shareable link Sorry, a shareable link is not currently available for this article. 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