DOCSLIB.ORG

Insights from the Spatial Distribution of Floor-Fractured and Concentric Craters

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Insights from the Spatial Distribution of Floor-Fractured and Concentric Craters 52nd Lunar and Planetary Science Conference 2021 (LPI Contrib. No. 2548) 2245.pdf EVIDENCE FOR THE LUNAR PROCELLARUM BASIN: INSIGHTS FROM THE SPATIAL DISTRIBUTION OF FLOOR-FRACTURED AND CONCENTRIC CRATERS. S. Ravi and M.S. Robinson, School of Earth and Space Exploration, Arizona State University, Tempe, AZ – 85282, USA (Email: [email protected]) Introduction: Floor-fractured (FFCs) and Camera (LROC) Wide Angle Camera (WAC) GLD 100 DTM concentric craters (CCs) are impact craters that [13]. underwent modification by volcano-tectonic processes Both FFCs and CCs appear to be clustered within such as viscous relaxation or magmatic intrusion impact basins, with >60% of FFCs and CCs following basin-forming events (Fig. 1) [1-6]. concentrated along the western boundary of the proposed Procellarum basin [10] (Fig. 2). Whether the spatial distribution of FFCs and CCs are random or genetically related to impact basins is not well understood. If the latter is true, then we can not only use FFCs and CCs as proxies for identifying ancient basin Figure 1: Characteristics of floor-fractured and concentric rims, but we can also infer local and regional variations craters. (A) Vitello crater (D = 40km) exhibits radial/concentric fractures, (B) Gassendi crater (D = 100km) in the strength of the lunar lithosphere. Therefore, the exhibits mare basalt infill, and (C) an unnamed concentric overarching goal of this study is to determine and crater (D = 5km) exhibits an uplifted concentric ridge. analyze the statistical significance of the spatial distribution of FFCs and CCs with respect to impact The Procellarum KREEP Terrane (PKT) is one of basins. three major crustal provinces on the Moon [7]. Data Methods: We used the multi-distance spatial from the Lunar Prospector Gamma Ray Spectrometer clustering analysis (Ripley’s K-function or RKF) tool shows that the PKT is a geochemically distinct province (ArcGIS) to compute the spatial dependence of FFCs whose boundary is marked by the abundance of rare and CCs over a range of distances, particularly with earth elements (REEs; Fig. 2) [8]. There are two respect to concentric peak rings of impact basins (Fig. 3). competing hypotheses for the origin of the PKT. 1) The The RKF computes two correlation values: observed presence of the PKT and the crustal asymmetry is K value and expected K value. If observed K value > attributed to the formation of a “Gargantuan Basin” later expected K value, then the population is clustered. If known as the Procellarum basin early in lunar history at the observed K value < expected K value, then the ~ 4.1-4.2 Ga [9-10]. The Procellarum basin is bound by population is dispersed. Mare Frigoris to the north, Mare Vaporum to the east, The diff K value (observed K – expected K) Mare Cognitum to the south and Oceanus Procellarum determines the significance of clustering. The larger the to the west (Fig. 3) [10]. 2) The presence of the PKT is diff K, the more significant the clustering of a given attributed as solely the result of the Imbrium impact population. We also computed the diff K values for the event [11-12]. In this model the proposed boundary of Procellarum basin rim that we outlined using FFCs and CCs and that of Wilhelms (1987) [10]. the Procellarum basin [10] is interpreted to be the outer ring of the Imbrian basin [11-12]. Figure 3: Baseline dataset. Concentric rings represent basin Figure 2: Spatial distribution of FFCs and CCs. The PKT is rings and zones over which the randomness of crater outlined in red. Base map: Lunar Reconnaissance Orbiter 52nd Lunar and Planetary Science Conference 2021 (LPI Contrib. No. 2548) 2245.pdf populations was calculated. Base map: LROC WAC GLD100 statistical evidence for the Procellarum basin as the [13]. origin of the enigmatic PKT. The spatial distribution of 85% FFCs and CCs Results and Discussion: Based on the RKF provides evidence for the existence of the Procellarum analysis, we noted that the observed K value is > the basin (a pre-Nectarian basin), consistent with that of expected K value for FFC and CC populations previous studies [9-10] and the argument that FFCs and associated with all basins, statistically verifying our CCs occur in regions of subdued basin topography (i.e., visual observation that FFCs and CCs are clustered thin and weak crust), in particular, where the crust- within basins. Additionally, the diff K (i.e., the mantle interface was uplifted. The evidence for the significance of clustering) is highest for FFCs and CCs existence of the Procellarum basin also addresses associated with pre-Nectarian basins (i.e., the oldest previous studies that noted the lack of floor-fractured basins which exhibit subdued topographic rims and and concentric craters associated with the Imbrium weak gravity anomalies [14]) compared to relatively basin – since it is superposed within the Procellarum younger basins (Figs. 4-5). This correlation with pre- basin, at a time when the lunar lithosphere was likely Nectarian basins suggests viscous relaxation is a relatively rigid, as evidenced by the presence of the plausible formation mechanism for FFCs and CCs. Appenine mountains, which were uplifted during the Since FFCs and CCs share the same geospatial Imbrium impact event [9-10]. distribution, but only vary in size, we interpret that these Acknowledgments: This research is supported by two landforms are on a continuum and that they were the Lunar Reconnaissance Orbiter (LRO) project. likely formed by the similar processes. References: [1] Schultz P.H. (1976) The Moon, 15, 241-273. [2] Jozwiak L.M. et al. (2012) JGR, 117, E11005. [3] Jozwiak L.M. et al. (2017) Icarus, 283, 224-231. [4] Trang D et al. (2017) Icarus, 278, 62-78. [5] Ravi S. and Robinson M.S. (2019) LPSC L #2677. [6] Hall J.L. et al. (1981) JGR, 86, 9537-9552. [7] Jolliff B.L. et al. (2000). JGR, 105, 4197-4216. [8] Wieczorek et al. (2000). JGR, 105, 20417-20430. [9] Cadogan P.H. (1974) Nature, 250, 315-316. [10] Wilhelms D.E. (1987) USGS Prof. Paper 1348. [11] Schultz P.H. and Spudis P.D. (1985) LPI 16. [12] Spudis P.D. and Schultz P.H. (1985) LPI 16. [13] Scholten F et al. (2012) Figure 4: Spatial distribution of FFCs and CCs with respect JGR, 117, E00H17. [14] Mohit P.S. and Phillips R.J. to pre-Nectarian basins. Base map: LROC WAC GLD100 (2006) JGR, 111, E12001. [13]. Figure 5: Circumstantial evidence for the Procellarum basin. Base map: LROC WAC GLD100 [13]. Diff K calculations show more significant clustering associated with our Procellarum basin rim compared to that of Wilhelms (1987) [10], thereby providing .
Load more

Recommended publications
  • No. 40. the System of Lunar Craters, Quadrant Ii Alice P
    NO. 40. THE SYSTEM OF LUNAR CRATERS, QUADRANT II by D. W. G. ARTHUR, ALICE P. AGNIERAY, RUTH A. HORVATH ,tl l C.A. WOOD AND C. R. CHAPMAN \_9 (_ /_) March 14, 1964 ABSTRACT The designation, diameter, position, central-peak information, and state of completeness arc listed for each discernible crater in the second lunar quadrant with a diameter exceeding 3.5 km. The catalog contains more than 2,000 items and is illustrated by a map in 11 sections. his Communication is the second part of The However, since we also have suppressed many Greek System of Lunar Craters, which is a catalog in letters used by these authorities, there was need for four parts of all craters recognizable with reasonable some care in the incorporation of new letters to certainty on photographs and having diameters avoid confusion. Accordingly, the Greek letters greater than 3.5 kilometers. Thus it is a continua- added by us are always different from those that tion of Comm. LPL No. 30 of September 1963. The have been suppressed. Observers who wish may use format is the same except for some minor changes the omitted symbols of Blagg and Miiller without to improve clarity and legibility. The information in fear of ambiguity. the text of Comm. LPL No. 30 therefore applies to The photographic coverage of the second quad- this Communication also. rant is by no means uniform in quality, and certain Some of the minor changes mentioned above phases are not well represented. Thus for small cra- have been introduced because of the particular ters in certain longitudes there are no good determi- nature of the second lunar quadrant, most of which nations of the diameters, and our values are little is covered by the dark areas Mare Imbrium and better than rough estimates.
    [Show full text]
  • TRANSIENT LUNAR PHENOMENA: REGULARITY and REALITY Arlin P
    The Astrophysical Journal, 697:1–15, 2009 May 20 doi:10.1088/0004-637X/697/1/1 C 2009. The American Astronomical Society. All rights reserved. Printed in the U.S.A. TRANSIENT LUNAR PHENOMENA: REGULARITY AND REALITY Arlin P. S. Crotts Department of Astronomy, Columbia University, Columbia Astrophysics Laboratory, 550 West 120th Street, New York, NY 10027, USA Received 2007 June 27; accepted 2009 February 20; published 2009 April 30 ABSTRACT Transient lunar phenomena (TLPs) have been reported for centuries, but their nature is largely unsettled, and even their existence as a coherent phenomenon is controversial. Nonetheless, TLP data show regularities in the observations; a key question is whether this structure is imposed by processes tied to the lunar surface, or by terrestrial atmospheric or human observer effects. I interrogate an extensive catalog of TLPs to gauge how human factors determine the distribution of TLP reports. The sample is grouped according to variables which should produce differing results if determining factors involve humans, and not reflecting phenomena tied to the lunar surface. Features dependent on human factors can then be excluded. Regardless of how the sample is split, the results are similar: ∼50% of reports originate from near Aristarchus, ∼16% from Plato, ∼6% from recent, major impacts (Copernicus, Kepler, Tycho, and Aristarchus), plus several at Grimaldi. Mare Crisium produces a robust signal in some cases (however, Crisium is too large for a “feature” as defined). TLP count consistency for these features indicates that ∼80% of these may be real. Some commonly reported sites disappear from the robust averages, including Alphonsus, Ross D, and Gassendi.
    [Show full text]
  • Glossary of Lunar Terminology
    Glossary of Lunar Terminology albedo A measure of the reflectivity of the Moon's gabbro A coarse crystalline rock, often found in the visible surface. The Moon's albedo averages 0.07, which lunar highlands, containing plagioclase and pyroxene. means that its surface reflects, on average, 7% of the Anorthositic gabbros contain 65-78% calcium feldspar. light falling on it. gardening The process by which the Moon's surface is anorthosite A coarse-grained rock, largely composed of mixed with deeper layers, mainly as a result of meteor­ calcium feldspar, common on the Moon. itic bombardment. basalt A type of fine-grained volcanic rock containing ghost crater (ruined crater) The faint outline that remains the minerals pyroxene and plagioclase (calcium of a lunar crater that has been largely erased by some feldspar). Mare basalts are rich in iron and titanium, later action, usually lava flooding. while highland basalts are high in aluminum. glacis A gently sloping bank; an old term for the outer breccia A rock composed of a matrix oflarger, angular slope of a crater's walls. stony fragments and a finer, binding component. graben A sunken area between faults. caldera A type of volcanic crater formed primarily by a highlands The Moon's lighter-colored regions, which sinking of its floor rather than by the ejection of lava. are higher than their surroundings and thus not central peak A mountainous landform at or near the covered by dark lavas. Most highland features are the center of certain lunar craters, possibly formed by an rims or central peaks of impact sites.
    [Show full text]
  • South Pole-Aitken Basin
    Feasibility Assessment of All Science Concepts within South Pole-Aitken Basin INTRODUCTION While most of the NRC 2007 Science Concepts can be investigated across the Moon, this chapter will focus on specifically how they can be addressed in the South Pole-Aitken Basin (SPA). SPA is potentially the largest impact crater in the Solar System (Stuart-Alexander, 1978), and covers most of the central southern farside (see Fig. 8.1). SPA is both topographically and compositionally distinct from the rest of the Moon, as well as potentially being the oldest identifiable structure on the surface (e.g., Jolliff et al., 2003). Determining the age of SPA was explicitly cited by the National Research Council (2007) as their second priority out of 35 goals. A major finding of our study is that nearly all science goals can be addressed within SPA. As the lunar south pole has many engineering advantages over other locations (e.g., areas with enhanced illumination and little temperature variation, hydrogen deposits), it has been proposed as a site for a future human lunar outpost. If this were to be the case, SPA would be the closest major geologic feature, and thus the primary target for long-distance traverses from the outpost. Clark et al. (2008) described four long traverses from the center of SPA going to Olivine Hill (Pieters et al., 2001), Oppenheimer Basin, Mare Ingenii, and Schrödinger Basin, with a stop at the South Pole. This chapter will identify other potential sites for future exploration across SPA, highlighting sites with both great scientific potential and proximity to the lunar South Pole.
    [Show full text]
  • Arxiv:0706.3947V1
    Transient Lunar Phenomena: Regularity and Reality Arlin P.S. Crotts Department of Astronomy, Columbia University, Columbia Astrophysics Laboratory, 550 West 120th Street, New York, NY 10027 ABSTRACT Transient lunar phenomena (TLPs) have been reported for centuries, but their nature is largely unsettled, and even their existence as a coherent phenomenon is still controversial. Nonetheless, a review of TLP data shows regularities in the observations; a key question is whether this structure is imposed by human observer effects, terrestrial atmospheric effects or processes tied to the lunar surface. I interrogate an extensive catalog of TLPs to determine if human factors play a determining role in setting the distribution of TLP reports. We divide the sample according to variables which should produce varying results if the determining factors involve humans e.g., historical epoch or geographical location of the observer, and not reflecting phenomena tied to the lunar surface. Specifically, we bin the reports into selenographic areas (300 km on a side), then construct a robust average count for such “pixels” in a way discarding discrepant counts. Regardless of how we split the sample, the results are very similar: roughly 50% of the report count originate from the crater Aristarchus and vicinity, 16% from Plato, 6% from recent, major impacts (Copernicus, ∼ ∼ Kepler and Tycho - beyond Aristarchus), plus a few at Grimaldi. Mare Crisium produces a robust signal for three of five averages of up to 7% of the reports (however, Crisium subtends more than one pixel). The consistency in TLP report counts for specific features on this list indicate that 80% of the reports arXiv:0706.3947v1 [astro-ph] 27 Jun 2007 ∼ are consistent with being real (perhaps with the exception of Crisium).
    [Show full text]
  • Downloaded from LRO Data Collections ( Accesed on 30 August 2020)
    remote sensing Article Maria Basalts Chronology of the Chang’E-5 Sampling Site Zhen Xu 1,2, Dijun Guo 3 and Jianzhong Liu 1,4,* 1 Center of Lunar and Planetary Sciences, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China; [email protected] 2 University of Chinese Academy of Sciences, Beijing 100049, China 3 Institute of Remote Sensing and Geographical Information System, School of Earth and Space Sciences, Peking University, Beijing 100871, China; [email protected] 4 CAS Center for Excellence in Comparative Planetology, Hefei 230026, China * Correspondence: [email protected]; Tel.: +86-137-1861-1998 Abstract: Chang’E-5 is the first lunar sample return mission of China. The spacecraft was landed in the northwest of the Procellarum KREEP Terrane (43.0576◦N, 308.0839◦E) on 1 December 2020 and returned 1731 g samples from a previously unvisited region. The landing area has been proposed as one of the youngest mare basalt units of the Moon and holds important information of lunar thermal evolution and chronology. However, the absolute model ages estimated in previous studies are quite different, ranging from 2.07 Ga to 1.21 Ga. Such significant difference may be caused by (1) different crater counting areas, (2) different crater diameter ranges, (3) effects of secondary craters, and (4) biases in crater identification. Moreover, the accurate landing site was unknown and the ages were estimated over the Eratosthenian-aged mare unit (Em4) instead. In light of the above unsatisfactory conditions, this study seeks to establish a standard crater size-frequency distribution of the CE-5 landing site.
    [Show full text]
  • Volcanoes and Lava Flows
    What Are The Types of What Did Native Volcanoes? Americans See? Craters of the Moon has three kinds of volcanoes to “The area now known as Craters of the Moon see. Laidlaw Volcano and Pillar Butte are Shield is important to the Shoshone-Bannock because Volcanoes that form when liquid rock oozes and it represents both a place of sacred power and flows out of a central vent. Pilot Butte and Lava Butte an ancestral ground crossed during seasonal are Cinder Cone Volcanoes that formed when migrations. The lava rock was heated in our liquid rocks spatters and spits up from of a central sweat lodges and it was the rock that sent our vent. Big Southern Butte, like Oregon's Mount St. prayers up to the creator. In the landscape of Helens, is a Volcanic Dome which forms when liquid the lava flows, harmony was found.” rock is at hotter temperatures and can be expolsive. -Laverne Broncho, Shoshone-Bannock Tribal Member How Old Are The Lava Flows? Southern Idaho has 12 volcanic fields that range from 0.5 million years old near its eastern border with Yellowstone National Park to 15 million years old near its western border with Oregon. Craters of the Moon is part of a volcanic field in south-central Idaho that formed 11 million years ago. At Craters of the Moon, the most recent series of lava flowed from volcanoes as recent as 2,100 years ago. Learn more. Shoshone legend speaks of a serpent on a mountain who, angered by lightning, coiled around it and squeezed until liquid rock flowed, fire shot from cracks, and the mountain exploded.
    [Show full text]
  • Geology of Shackleton Crater and the South Pole of the Moon Paul D
    GEOPHYSICAL RESEARCH LETTERS, VOL. 35, L14201, doi:10.1029/2008GL034468, 2008 Geology of Shackleton Crater and the south pole of the Moon Paul D. Spudis,1 Ben Bussey,2 Jeffrey Plescia,2 Jean-Luc Josset,3 and Ste´phane Beauvivre4 Received 28 April 2008; revised 10 June 2008; accepted 16 June 2008; published 18 July 2008. [1] Using new SMART-1 AMIE images and Arecibo and details new results on the lighting conditions of the poles Goldstone high resolution radar images of the Moon, we [e.g., Bussey et al., 2008]. investigate the geological relations of the south pole, including the 20 km-diameter crater Shackleton. The south 2. Geological Setting of the South Pole pole is located inside the topographic rim of the South Pole- Aitken (SPA) basin, the largest and oldest impact crater on [3] The dominant feature that influences the geology and the Moon and Shackleton is located on the edge of an topography of the south polar region is the South Pole- interior basin massif. The crater Shackleton is found to be Aitken (SPA) basin, the largest and oldest impact feature on older than the mare surface of the Apollo 15 landing site the Moon [e.g., Wilhelms, 1987]. This feature is over 2600 (3.3 Ga), but younger than the Apollo 14 landing site km in diameter, averages 12 km depth, and is approximately (3.85 Ga). These results suggest that Shackleton may have centered at 56° S, 180° [Spudis et al., 1994]. The basin collected extra-lunar volatile elements for at least the last formed sometime after the crust had solidified and was rigid 2 billion years and is an attractive site for permanent human enough to support significant topographic expression; thus, presence on the Moon.
    [Show full text]
  • Constraining the Size of the South Pole-Aitken Basin Impact ⇑ R.W.K
    Icarus 220 (2012) 730–743 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Constraining the size of the South Pole-Aitken basin impact ⇑ R.W.K. Potter a, , G.S. Collins a, W.S. Kiefer b,c, P.J. McGovern b,c, D.A. Kring b,c a Impacts and Astromaterials Research Centre, Dept. of Earth Science and Engineering, Imperial College London, London SW7 2AZ, UK b Center for Lunar Science and Exploration, Lunar and Planetary Institute, 3600 Bay Area Boulevard, Houston, TX 77058, USA c NASA Lunar Science Institute article info abstract Article history: The South Pole-Aitken (SPA) basin is the largest and oldest definitive impact structure on the Moon. To Received 13 October 2011 understand how this immense basin formed, we conducted a suite of SPA-scale numerical impact simu- Revised 21 May 2012 lations varying impactor size, impact velocity, and lithospheric thermal gradient. We compared our Accepted 23 May 2012 model results to observational SPA basin data to constrain a best-fit scenario for the SPA basin-forming Available online 13 June 2012 impact. Our results show that the excavation depth-to-diameter ratio for SPA-scale impacts is constant for all impact scenarios and is consistent with analytical and geological estimates of excavation depth Keywords: in smaller craters, suggesting that SPA-scale impacts follow proportional scaling. Steep near-surface ther- Impact processes mal gradients and high internal temperatures greatly affected the basin-forming process, basin structure Cratering Moon and impact-generated melt volume. In agreement with previous numerical studies of SPA-scale impacts, Collisional physics crustal material is entirely removed from the basin center which is instead occupied by a large melt pool of predominantly mantle composition.
    [Show full text]
  • North Polar Region Craterforms on Mars: Geometric Characteristics from the Mars Orbiter Laser Altimeter
    Icarus 144, 329–352 (2000) doi:10.1006/icar.1999.6298, available online at http://www.idealibrary.com on North Polar Region Craterforms on Mars: Geometric Characteristics from the Mars Orbiter Laser Altimeter James B. Garvin NASA–Goddard Space Flight Center, Geodynamics, Code 921, Greenbelt, Maryland 20771 E-mail: [email protected] Susan E. H. Sakimoto USRA at NASA–Goddard Space Flight Center, Code 921, Greenbelt, Maryland 20771 James J. Frawley Herring Bay Geophysics, Raytheon-STX, at NASA–Goddard Space Flight Center, Code 921, Greenbelt, Maryland 20771 and Charles Schnetzler SSAI at NASA–Goddard Space Flight Center, Code 920, Greenbelt, Maryland 20771 Received February 15, 1999; revised September 20, 1999 geologically recent surface, with evidence of effusive volcanism and This study focuses on topographic characterization of ice- enhanced sedimentation. In addition, the measured impact crater associated north polar region impact craters and several enigmatic depths for ice-associated craters suggest at least a few cases of en- polar craterforms using new information from the Mars Orbiter hanced excavation and thus a possibly weaker target relative to the Laser Altimeter (MOLA), an instrument aboard the Mars Global typical northern hemisphere plains. c 2000 Academic Press Surveyor (MGS) orbiter. We find that, for ice-associated craters, the Key Words: Mars; impact craters; polar processes; ejecta; topography reveals several surprising results not previously appar- volcanism. ent from orbital images alone. First, geometric properties for several impact craters associated with ice and frost deposits suggest that cavity infill is as high as 80% of reconstructed, preerosion levels. INTRODUCTION Second, craters associated with ice also demonstrate unique cav- ity geometries relative to their nonpolar counterparts.
    [Show full text]
  • Activity in the Lunar Surface: Transient Lunar Phenomena
    Activity in the lunar surface: Transient Lunar Phenomena Cruz Roa, Andr´esFelipe ∗ October 1, 2012 ABSTRACT Transient Lunar Phenomena (TLP) observed on the surface of the moon, are of high rarity, low repetition rate and very short observation times, resulting in that there is little information about this topic. This necessitates the importance of studying them in detail. They have been observed as very bright clouds of gases of past geological lunar activity. According its duration, there have been registered in different colors (yellow, orange, red). Its size can vary from a few to hundreds of kilometers. The TLP Usually occur in certain locations as in some craters (Aristarchus, Plato, Kepler, etc.) and at the edges of lunar maria (Sea of Fecundity, Alps hills area, etc.). The exposure time of a TLP can vary from a few seconds to a little more than one hour. In this paper, a literature review of the TLP is made to build a theory from the existing reports and scientific hypotheses, trying to unify and synthesize data and concepts that are scattered by different lunar research lines. The TLP need to be explained from celestial mechanics and planetary astrophysics to explain the possible causes from phenomena such as outgassing moon, moonquakes and the gravitational interaction. Extrapolating these hypothetical physical knowledge, arguments are exposed for Lunar degassing theory showing this as the most consistent. It's build also a the theory of how to observe, describe, explain and predict the TLP. Keywords: transient lunar phenomena, lunar geologic activity, lunar outgassing, moonquakes, gravitational interaction. 1 INTRODUCTION 1.1 What is TLP? A TLP is an explosive emanation of waste gases deposited under lunar soil produced by geological lunar activity, possibly originated by a moonquake because of the gravitational pull of the Earth-Moon system.
    [Show full text]
  • Two Types of Terrain Exposed in the Upper Crater Wall of Shackleton Crater, Lunar South Pole: Implications for Future Landings
    51st Lunar and Planetary Science Conference (2020) 1148.pdf TWO TYPES OF TERRAIN EXPOSED IN THE UPPER CRATER WALL OF SHACKLETON CRATER, LUNAR SOUTH POLE: IMPLICATIONS FOR FUTURE LANDINGS. Harish1, N. Barrett2, S. J. Boazman3,4, A. J. Gawronska5, C. M. Gilmour6, S.H. Halim7, K. McCanaan8, A. V. Satyakumar9, J. Shah10 and D. A. Kring11,12. 1Physical Research Laboratory, India (email: [email protected]). 2University of Alberta, Edmonton, Canada. 3Natural History Museum, London, UK. 4University College London, UK. 5Miami University, Ohio, USA. 6York University, Toronto, Canada. 7Birkbeck, University of London, UK. 8University of Manchester, UK. 9CSIR – National Geophys- ical Research Institute (CSIR-NGRI), India. 10The University of Western Ontario, London, Canada. 11Lunar and Plan- etary Institute, Universities Space Research Association, Houston, TX, USA. 12NASA Solar System Exploration Re- search Virtual Institute. Introduction: Shackleton is an Imbrian aged (~3.5 using LRO Narrow Angle Camera (NAC) images [13]. Ga), ~20 km diameter, and ~4 km deep impact crater at The NAC images were processed and projected to a lu- the lunar south pole (Fig. 1) along the margin of the nar polar stereographic perspective using the Integrated South Pole-Aitken (SPA) basin [1,2]. The site is the tar- Software for Imagers and Spectrometers (ISIS) 3 soft- get of the next human mission to the lunar surface [3] ware. and one of five proposed landing sites of potential sci- Results and discussion: Shackleton crater pene- entific interest [4]. It is an attractive landing site because trates at least two types of terrains: one dominated by of its proximity to permanently shadowed regions crystalline crustal rocks, including purest anorthosite (PSRs) that may contain water and other volatiles suita- (PAN), and the other composed of strata.
    [Show full text]