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Polar Ice in the Solar System

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Polar Ice in the Solar System Recommended Reading List for Polar Ice in the Inner Solar System Compiled by: Shane Byrne Lunar and Planetary Laboratory, University of Arizona. April 23rd, 2007 Polar Ice on Airless Bodies................................................................................................. 2 Initial theories and modeling results for these ice deposits: ........................................... 2 Observational evidence (or lack of) for polar ice on airless bodies:............................... 3 Martian Polar Ice................................................................................................................. 4 Good (although dated) introductory material ................................................................. 4 Polar Layered Deposits:...................................................................................................... 5 Ice-flow (or lack thereof) and internal structure in the polar layered deposits............... 5 North polar basal-unit ..................................................................................................... 6 Geologic Mapping and impact cratering......................................................................... 6 Connection of polar layered deposits (PLD) to climate.................................................. 7 Formation of troughs, scarps and chasmata.................................................................... 7 Surface Properties of the PLD ........................................................................................ 8 Eolian Processes and circumpolar dunes ........................................................................ 8 Residual Ice Caps:............................................................................................................. 10 Geomorphology, composition and changes within the Southern Residual Ice Cap..... 10 Geomorphology and composition of the Northern Residual Ice Cap........................... 11 Seasonal Ice Caps: ............................................................................................................ 12 Omissions A reading list for terrestrial polar ice deposits and processes is totally beyond the scope of a document like this, so I have only included papers discussing terrestrial ice when there is a useful analogy to some extra-terrestrial example. Outer solar system satellites are often primarily composed of various ices and display their own menagerie of surface processes and morphologies. A complete treatment of these bodies requires a separate reading list. 1 Polar Ice on Airless Bodies Icy deposits have been hypothesized to exist in permanently shadowed craters in the polar regions of the Moon and Mercury for some time e.g. Watson et al. [1961]. A planet’s atmosphere can usually transport heat into areas where the sun never reaches; however, on an airless body this process is absent. In permanently shadowed areas, such as within polar impact craters, ice may collect and remain stable over the age of the solar system. Strong evidence for Mercury’s polar ice deposits has been acquired; however, evidence for substantial amounts of polar ice on the Moon remains weak. Despite this, there is currently considerable interest in any possible lunar ice due to its potential to be explored by a manned mission. Initial theories and modeling results for these ice deposits: Arnold, J. R. (1979), Ice in the lunar polar regions, J. Geophys. Res., 84(B10), 5659– 5667. Butler, B. J. (1997), The migration of volatiles on the surfaces of Mercuryand the Moon, J. Geophys. Res., 102(E8), 19,283– 19,291. Cocks, F., P. Klenk, S. Watkins, W. Simmons, J. Cocks, E. Cocks, and J. Sussingham (2002), Lunar ice: Adsorbed water on subsurface polar dust, Icarus, 160, 386–397. Moses, J. I., K. Rawlins, K. Zahnle, and L. Dones (1999), External sources of water for Mercury’s putative ice deposits, Icarus, 137, 197–221, doi:10.1006/icar.1998.6036. Lanzerotti, L., W. L. Brown, and R. E. Johnson (1981), Ice in the polar regions of the moon, J. Geophys. Res., 86, 3949–3950. Lawrence, D. J., W. C. Feldman, R. C. Elphic, J. J. Hagerty, S. Maurice, G. W. McKinney, and T. H. Prettyman (2006), Improved modeling of Lunar Prospector neutron spectrometer data: Implications for hydrogen deposits at the lunar poles, J. Geophys. Res., 111, E08001, doi:10.1029/2005JE002637. Salvail, J. R. and F. P. Fanale (1994), Near-surface ice on Mercury and the Moon: A topographic thermal model, Icarus, 111, 441-455. Schorghofer, N. and G. J. Taylor (2007), Subsurface migration of H2O at lunar cold traps, J. Geophys. Res., 112, 2010 Vasavada, A. R., D. A. Paige, and S. E. Wood (1999), Near-surface temperatures on Mercury and the Moon and the stability of polar ice deposits, Icarus, 141, 179-193. Watson, K., B. Murray, and H. Brown (1961), On the Possible Presence of Ice on the Moon, J. Geophys. Res., 66, 1598 Watson, K., B. C. Murray, and H. Brown (1961), The behavior of volatiles on the lunar surface, J. Geophys. Res., 66, 3033-3045. Watson, K., B. C. Murray, and H. Brown (1962), The stability of volatiles in the solar system, Icarus, 1, 317-327. Zuber, M. T. and D. E. Smith (1997), Topography of the lunar south polar region: Implications for the size and location of permanently shaded areas, Geophys. Res. Lett., 24, 2183 2 Observational evidence (or lack of) for polar ice on airless bodies: Bussey, D. B. J., P. G. Lucey, D. Steutel, M. S. Robinson, P. D. Spudis, and K. D. Edwards (2003), Permanent shadow in simple craters near the lunar poles, Geophys. Res. Lett., 30, 11-1. Butler, B. J., D. O. Muhleman, and M. A. Slade (1993), Mercury: Full-disk radar images and the detection and stability of ice at the North Pole, J. Geophys. Res., 98(E8), 15,003– 15,024. Campbell, B. A., D. B. Campbell, A. A. H. J. F. Chandler, M. C. Nolan, and P. J. Perillat (2003), Radar imaging of the lunar poles, Nature, 426,137–138. Campbell, D. B., B. A. Campbell, L. M. Carter, J.-L. Margot, and N. J. S. Stacy (2006), No evidence for thick deposits of ice at the lunar south pole, Nature, 443, 835-837. Feldman, W., S. Maurice, B. B. A. B. Binder, R. Elphic, and D. Lawrence (1998), Fluxes of fast and epithermal neutrons from lunar prospector: Evidence for water ice at the lunar poles, Science, 281(5382), 1496–1500. Harmon, J. K., M. A. Slade, R. A. Velez, A. Crespo, M. J. Dryer, and J. M.Johnson (1994), Radar mapping of Mercury’s polar anomalies, Nature, 369, 213–215, doi:10.1038/369213a0. Harmon, J. K., P. J. Perillat, and M. A. Slade (2001), High-resolution radarimaging of Mercury’s north pole, Icarus, 149, 1 – 15, doi:10.1006/icar.2000.6544. Margot, J. L., D. B. Campbell, R. F. Jurgens, and M. A. Slade (1999), Topography of the lunar poles from radar interferometry: A survey of cold trap locations, Science, 284, 1658-1660. Nozette, S., C. L. Lichtenberg, P. D. Spudis, R. Bonner, W. Ort, E. Malaret, M. Robinson, and E. M. Shoemaker (1996), The Clementine Bistatic Radar Experiment, Science, 274, 1495–1498. Slade, M. A., B. J. Butler, and D. O. Muhleman (1992), Mercury radar imaging— Evidence for polar ice, Science, 258, 635–640. 3 Martian Polar Ice The icy polar deposits on Mars can be naturally divided into the polar layered deposits (PLD) and the residual ice caps (RIC) that partially cover them. In addition to these more permanent deposits, a seasonal ice cap of CO2 ice condenses from the atmosphere each winter season and sublimates away the following summer. Good (although dated) introductory material Clifford, S. M., et al. (2000), The state and future of Mars polar science and exploration, Icarus, 144, 210–242. James, P. B., H. H. Kieffer, and D. A. Paige (1992), The seasonal cycle of carbon dioxide on Mars, in Mars, edited by H. H. Kieffer, B. M. Jakosky, C. W. Snyder, and M. S. Matthews, pp. 934-968, Univ. of Arizona Press. Tanaka, K. L., and D. Scott (1987), Geologic Map of the Polar Regions of Mars, U.S. Geol. Surv. Misc. Invest. Ser., Map I-1802-C. Thomas, P. C., S. W. Squyres, K. E. Herkenhoff, A. Howard, and B. C. Murray (1992), Polar deposits of Mars, in Mars, edited by H. H. Kieffer, B. M. Jakosky, C. W. Snyder, and M. S. Matthews, pp. 767–795, Univ. of Arizona Press. Vasavada, A. R., J. Williams, D. A. Paige, K. E. Herkenhoff, N. T. Bridges, R. Greeley, B. C. Murray, D. S. Bass, and K. S. McBride (2000), Surface properties of Mars’ polar layered deposits and polar landing sites, J. Geophys. Res., 105 (E3), 6961–6970. Mars polar science has recently benefited immensely by three international conferences on Mars polar science and exploration. Special issues of Icarus were published for each of these conferences in volumes 144(2), 154(1) and 174(2). These volumes contain much of the recent work in this area. 4 Polar Layered Deposits: The PLD at both poles are about 3km thick, 1000km across and almost pure H2O ice (with dust contaminants on the order of 1%). Their layered nature is thought to be driven by climatic change during their deposition, in a similar way to how past climate on Earth is recorded in terrestrial ice cores. Climatic variation on Mars is primarily driven by variations in the planet’s orbital elements and obliquity, analogous to Milankovitch cycles on the Earth. Recently identified mid-latitude ice-rich deposits are though to have originated from the PLD. Ice-flow (or lack thereof) and internal structure in the polar layered deposits. Budd, W. F., D. Jenssen, J. H. I. Leach, I. N. Smith, and U. Radok (1986), The north polar cap of Mars as a steady-state system, Polarforschung, 56, 43–63. Byrne, S., and A. B.
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