Central Peaks in Lunar Craters : Morphology and Morphometry

Total Page:16

File Type:pdf, Size:1020Kb

Central Peaks in Lunar Craters : Morphology and Morphometry CENTRAL PEAKS IN LUNAR CRATERS : MORPHOLOGY AND MORPHOMETRY. Wendy Hale and James W. Head, Dept. of Geological Sciences, Erown University, Provi- dence, R I 02912. Central peaks are an important structural and morphological feature of fresb craters on the Moon. Previous work has established their occurrence as a function of fresh crater size (100% in craters with diameters >35 km), 1 their relationship to substrate type (more frequent occurrence in mare craters than in highland craters below%35 ki lometers),' thei r abundance as a function of crater type,' that peak height is directly proportional to crater diameter (h = .006 D~,~.'~),~"and that a transition from central peak craters to cen- tral peak basins to peak ring basins occurs at d iameters between 150-250 km.4'5 A1 though virtua l l y a l l workers agree that central peaks are related to ~hcsurrounding impact crater in origin, there is uncertainty about the rode of formation, with some associating peak formation with the gravity-induced fa; ure of the transient cavity during the modification stage of the cratering event, 6 a7d others proposing that central uplift begins during the excavation stag', initiated by high stresses associated with shock and rarefaction waves ccnc~ntratedin the sub-impact p~int.~'~Relati~nships between central peak hsicjht and crater diameter,3 and the diameters of transition to central peak zna peak-ring basins on different planets4 have been cited as evidence favor- ing the latter view. The purpose of the present study is to examine central peak regions in fresh lunar craters in order to I ) define a relationship be- tlween diameter of central peaks, and crater rim crest and floor diameter, 2) characterize their morphology, 3) provide a stronger basis for comparison of central peaks to peak rings in lunar basins, and 4) assess the effects of degradation. In order to minimize effects from erosion and degradation, only the mor- pholog;cally freshest examples of craters with central peaks were chosen for study (n = 175; Copernican to lmbrian in age). Measurements were made from [Lunar Orbiter and Apol lo images and topographic Taps (LTO series). Craters in the diameter range between central peak onset and 17 km were not included because of the morphologic comp levity of the crater interior.'" The sample includes 90 nearside craters, which comprise 98% of all fresh nearside craters with central peaks as l isted in the LPL catalogue, as we1 l as 85 craters from polar and farside regions. In addition, 29 craters of pre- lmbrian age with prominent central peaks were measured to test for evidence of degradation in periods of more intense erosion. For each crater, meas- urements were made of rim crest diameter (Drc), f loor diameter (Df 1, crater age, central peak morphology, and central peak diameter (Dcp). Since central peaks commonly occur in i rregu lar clusters, the latter val ue is not as easi ly defined as Drc or Df . We def ine Dcp here as the d iameter of a best-f i t c i rc l e enclosing all of the central peak mass. I) Relationship between Drc and Dcp - A plot of Drc versus central peak region diameter (Dcp) for the fresh crater population (Figure I) shows a linear relationship defined by Dcp = 0.259 Drc - 2.57 (r = 0.88) for the popu- lation diameter range of 17-180 km. A previous study of central peak areas for central peak craters of all states of degradation in the central nearside region showed only a poor correlation between increasing peak area and crater diameter.g Apparently all craters with central peaks were included in this studyg regardless of degradation state, a factcr that may have added to the scatter of the data. 2) Relationship between Df and Dcp - Measurements of crater floor diam- eter for the same population of craters yields a linear relationship between Df and D (Dcp = 0.398 Df - 0.51; r = 87) (Figure 2). cP 0 Lunar and Planetary Institute Provided by the NASA Astrophysics Data System CENTRAL PEAKS IN LUNAR CRATERS Hale, W. and Head, J.W. 3) Morphological characteristics of central peaks - Central peaks were classified according to their morphological complexity and geometry. Simple peaks are either single peaks or single coherent ridges while complex peaks are clusters of peaks, of either symmetrica I, I inear, or arcuate geometry. The distribution of these types as a function of diameter is shown in Figure 3. The same population was subdivided according to peak geometry into I inear peaks (elongate sing l e ridges or c l usters), arcuate peaks (arcuate single ridges or clusters), and symmetrica I peaks (consisting of a single central ly located peak or centrally oriented clusters) (Figure 3). There is no clear trend in increasing peak complexity with increasing crater size. There is a sl ight tendency for peaks to be less symmetrical with increasing crater size. 4) Substrate influence on peak complexity and morphology - Table I shows the distribution of subdivisions of the complexity and geometry classifica- tions as a function of substrate type. Central peak complexity appears in- sensitive to substrate type. However, development of l inear central peaks appears to be favored in hiqhland- terrain. 5) Pre-lmbrian central peak craters - Twenty-nine central peak craters of pre-lmbrian aqe (20-186 km in diameter) were analyzed. Central peak diam- eter for these ckters increases at a lower rate, rejative to rim crest diam- eter, then for fresh craters (Drc = 3.99 Dcp + 24.6; r = .76). They also increase at a lower rate relative to the floor (Df = 2.14 Dcp t 21.651, but at the same time the floor itself is increasing at a faster rate relative to the rim crest (Drc = 1.29 Df f 14.37). If these pre-lmbrian craters formed with the same initial geometry as later craters, these trends are easily explained by small additions of material to the crater floor (probably from degradation mechanisms8), causing widening of the floor and partial covering of the central peaks. Discussion and Conclusions - For fresh lunar craters, a I inear relation- ship has been shown for the morphometric parameters central peak diameter (Dcp) and rim crest (Drc) and floor diameter (Df). Linear relationships have previously been demonstrated for Drc and peak height3 and peak ring 4 diameter, and cited as evidence for these elements being related to the kinetic energy of impact. 3'4 These relationships differ for pre- lmbrian craters with central peaks in a manner consistent with the addition of small amounts of floor material probably resulting from the more intense degrada- tion of this period. There is no evidence for size or substrate control on peak complexity. Peak geometry is apparently not influenced by crater size, but linear peaks are more prominent in the highlands than the maria, perhaps due to highland crustal fractures. lo Several l ines of evidence suggest that the transition from craters to basins (peaks to peak rings) is more com- plicated than a sim le expansion of central peak complexity and size, as pre- vious ly proposed. "" First, there is no we1 I developed trend in simple to complex peak morphology as crater diameter increases. Secondly, the slope of the Drc/Dcp, l ine differs from that of the Drc/peak ring diameter establ ished previously. Analysis of the characteristics of craters and basins with transitions l morphologies is presently underway. References: 'wood C.A. and L. Andersson (1 978) PLSC9, 1267; inta tala M., C.A. Wood and J .W. Head ( 1977) PLSC8, 3409; 3~oodc.A.973) Icarus, 503; 4~ead J.W. (1978) Lunar Science IX, 485; 'wood, C.A. and J.W. Head (1976) PLSC7, 3629; 6~enceM. --et a1 . (19m) Shock ---Met. Nat. Mat., p. 368 and Gault D. --et al. (1975) J. Geophys. Res., 2444; 'Milton D. and D.J. Roddy (1972) IGC, Sess. 24, p. I19;-'~ead J .W. (1975) --Moon 12, 299; ien C. (1975) --Moon 12,463;'UStr-om R.G. (1964) -Corn. --Lunar Plan. -Lab., 205; ll~odgesC.(1978) PLSC9, 521. 0 Lunar and Planetary Institute Provided by the NASA Astrophysics Data System urajsLs lejaa s~!silydo~jsvVSVN ayj Lq pap!aoq . ajnj!jsuI L~sjauleldpun: mun? 0 CENTRAL PEAK REGION DIAMETER (Dcp) (km) 0 10 20 30 40 50 a CENTRAL PEAK REGION DIAMETER (Dcp) (km) 0 10203040~ - - ,.-. --K! - - PPP m u' E 4 --- - - P m-- -4 L1 Lx rN'J 0 0 IF m . -3s. *¶ xi in yi - 3-4 3% 'M'T pea^ pue .M 'aj~~ S831VH3 HVNfll Nt SlV3d lVHlN33 .
Recommended publications
  • Lunar Sourcebook : a User's Guide to the Moon
    4 LUNAR SURFACE PROCESSES Friedrich Hörz, Richard Grieve, Grant Heiken, Paul Spudis, and Alan Binder The Moon’s surface is not affected by atmosphere, encounters with each other and with larger planets water, or life, the three major agents for altering throughout the lifetime of the solar system. These terrestrial surfaces. In addition, the lunar surface has orbital alterations are generally minor, but they not been shaped by recent geological activity, because ensure that, over geological periods, collisions with the lunar crust and mantle have been relatively cold other bodies will occur. and rigid throughout most of geological time. When such a collision happens, two outcomes are Convective internal mass transport, which dominates possible. If “target” and “projectile” are of comparable the dynamic Earth, is therefore largely absent on the size, collisional fragmentation and annihilation Moon, and so are the geological effects of such occurs, producing a large number of much smaller internal motions—volcanism, uplift, faulting, and fragments. If the target object is very large compared subduction—that both create and destroy surfaces on to the projectile, it behaves as an “infinite halfspace,” Earth. The great contrast between the ancient, stable and the result is an impact crater in the target body. Moon and the active, dynamic Earth is most clearly For collisions in the asteroid belt, many of the shown by the ages of their surfaces. Nearly 80% of the resulting collisional fragments or crater ejecta escape entire solid surface of Earth is <200 m.y. old. In the gravitational field of the impacted object; many of contrast, >99% of the lunar surface formed more than these fragments are then further perturbed into 3 b.y.
    [Show full text]
  • Slope - Geologic Age Relationships in Complex Lunar Craters C
    49th Lunar and Planetary Science Conference 2018 (LPI Contrib. No. 2083) 2399.pdf SLOPE - GEOLOGIC AGE RELATIONSHIPS IN COMPLEX LUNAR CRATERS C. Rojas1, P. Mahanti1, M. S. Robinson1, LROC Team1, 1LROC Science Operation Center, School of Earth and Space Exploration, Arizona State University, Tempe, Arizona ([email protected]) Table 1: List of complex craters. *Copernican craters Introduction: Impact events leading to formation Crater D (km) Model Age (Ga) Lon Lat of basins and large craters dominate the early history Moore F* 24 0.041∓0.012 [8] 37.30 185.0 of the Moon [1] leading to kilometer scale topographic Wiener F* 30 0.017∓0.002 149.9740.90 variations on the lunar surface, with smaller crater [2], Klute W* 31 0.090∓0.007 216.7037.98 progressively introducing higher frequency topography. Necho* 37 0.080∓0.024 [8] 123.3 –5.3 Crater wall slopes represent most of the overall topo- Aristarchus* 40 0.175∓0.0095 312.5 23.7 graphic variation since many locations on the Moon are Jackson* 71 0.147∓0.038 [9] 196.7 22.1 craters. While impact events lead to the formation of McLaughlin 75 3.7∓0.1 [10] 267.1747.01 steep slopes [3], they are also primarily responsible for Pitiscus 80 3.8∓0.1 [10] 30.57 -50.61 landform degradation [4]. During crater formation, tar- Al-Biruni 80 3.8∓0.1 [10] 92.62 18.09 get properties and processes controlling structural sta- La Pérouse 80 3.6∓0.1 [10] -10.66 76.18 bility limit maximum slopes [4].
    [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]
  • Summary of Sexual Abuse Claims in Chapter 11 Cases of Boy Scouts of America
    Summary of Sexual Abuse Claims in Chapter 11 Cases of Boy Scouts of America There are approximately 101,135sexual abuse claims filed. Of those claims, the Tort Claimants’ Committee estimates that there are approximately 83,807 unique claims if the amended and superseded and multiple claims filed on account of the same survivor are removed. The summary of sexual abuse claims below uses the set of 83,807 of claim for purposes of claims summary below.1 The Tort Claimants’ Committee has broken down the sexual abuse claims in various categories for the purpose of disclosing where and when the sexual abuse claims arose and the identity of certain of the parties that are implicated in the alleged sexual abuse. Attached hereto as Exhibit 1 is a chart that shows the sexual abuse claims broken down by the year in which they first arose. Please note that there approximately 10,500 claims did not provide a date for when the sexual abuse occurred. As a result, those claims have not been assigned a year in which the abuse first arose. Attached hereto as Exhibit 2 is a chart that shows the claims broken down by the state or jurisdiction in which they arose. Please note there are approximately 7,186 claims that did not provide a location of abuse. Those claims are reflected by YY or ZZ in the codes used to identify the applicable state or jurisdiction. Those claims have not been assigned a state or other jurisdiction. Attached hereto as Exhibit 3 is a chart that shows the claims broken down by the Local Council implicated in the sexual abuse.
    [Show full text]
  • Ages of Large Lunar Impact Craters and Implications for Bombardment During the Moon’S Middle Age ⇑ Michelle R
    Icarus 225 (2013) 325–341 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Ages of large lunar impact craters and implications for bombardment during the Moon’s middle age ⇑ Michelle R. Kirchoff , Clark R. Chapman, Simone Marchi, Kristen M. Curtis, Brian Enke, William F. Bottke Southwest Research Institute, 1050 Walnut Street, Suite 300, Boulder, CO 80302, United States article info abstract Article history: Standard lunar chronologies, based on combining lunar sample radiometric ages with impact crater den- Received 20 October 2012 sities of inferred associated units, have lately been questioned about the robustness of their interpreta- Revised 28 February 2013 tions of the temporal dependance of the lunar impact flux. In particular, there has been increasing focus Accepted 10 March 2013 on the ‘‘middle age’’ of lunar bombardment, from the end of the Late Heavy Bombardment (3.8 Ga) until Available online 1 April 2013 comparatively recent times (1 Ga). To gain a better understanding of impact flux in this time period, we determined and analyzed the cratering ages of selected terrains on the Moon. We required distinct ter- Keywords: rains with random locations and areas large enough to achieve good statistics for the small, superposed Moon, Surface crater size–frequency distributions to be compiled. Therefore, we selected 40 lunar craters with diameter Cratering Impact processes 90 km and determined the model ages of their floors by measuring the density of superposed craters using the Lunar Reconnaissance Orbiter Wide Angle Camera mosaic. Absolute model ages were computed using the Model Production Function of Marchi et al.
    [Show full text]
  • GRAIL Gravity Observations of the Transition from Complex Crater to Peak-Ring Basin on the Moon: Implications for Crustal Structure and Impact Basin Formation
    Icarus 292 (2017) 54–73 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus GRAIL gravity observations of the transition from complex crater to peak-ring basin on the Moon: Implications for crustal structure and impact basin formation ∗ David M.H. Baker a,b, , James W. Head a, Roger J. Phillips c, Gregory A. Neumann b, Carver J. Bierson d, David E. Smith e, Maria T. Zuber e a Department of Geological Sciences, Brown University, Providence, RI 02912, USA b NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA c Department of Earth and Planetary Sciences and McDonnell Center for the Space Sciences, Washington University, St. Louis, MO 63130, USA d Department of Earth and Planetary Sciences, University of California, Santa Cruz, CA 95064, USA e Department of Earth, Atmospheric and Planetary Sciences, MIT, Cambridge, MA 02139, USA a r t i c l e i n f o a b s t r a c t Article history: High-resolution gravity data from the Gravity Recovery and Interior Laboratory (GRAIL) mission provide Received 14 September 2016 the opportunity to analyze the detailed gravity and crustal structure of impact features in the morpho- Revised 1 March 2017 logical transition from complex craters to peak-ring basins on the Moon. We calculate average radial Accepted 21 March 2017 profiles of free-air anomalies and Bouguer anomalies for peak-ring basins, protobasins, and the largest Available online 22 March 2017 complex craters. Complex craters and protobasins have free-air anomalies that are positively correlated with surface topography, unlike the prominent lunar mascons (positive free-air anomalies in areas of low elevation) associated with large basins.
    [Show full text]
  • Science Concept 3: Key Planetary
    Science Concept 6: The Moon is an Accessible Laboratory for Studying the Impact Process on Planetary Scales Science Concept 6: The Moon is an accessible laboratory for studying the impact process on planetary scales Science Goals: a. Characterize the existence and extent of melt sheet differentiation. b. Determine the structure of multi-ring impact basins. c. Quantify the effects of planetary characteristics (composition, density, impact velocities) on crater formation and morphology. d. Measure the extent of lateral and vertical mixing of local and ejecta material. INTRODUCTION Impact cratering is a fundamental geological process which is ubiquitous throughout the Solar System. Impacts have been linked with the formation of bodies (e.g. the Moon; Hartmann and Davis, 1975), terrestrial mass extinctions (e.g. the Cretaceous-Tertiary boundary extinction; Alvarez et al., 1980), and even proposed as a transfer mechanism for life between planetary bodies (Chyba et al., 1994). However, the importance of impacts and impact cratering has only been realized within the last 50 or so years. Here we briefly introduce the topic of impact cratering. The main crater types and their features are outlined as well as their formation mechanisms. Scaling laws, which attempt to link impacts at a variety of scales, are also introduced. Finally, we note the lack of extraterrestrial crater samples and how Science Concept 6 addresses this. Crater Types There are three distinct crater types: simple craters, complex craters, and multi-ring basins (Fig. 6.1). The type of crater produced in an impact is dependent upon the size, density, and speed of the impactor, as well as the strength and gravitational field of the target.
    [Show full text]
  • Physics of the Moon
    NASA TECHNICAL NOTE -cNASA TN D-2944 e. / PHYSICS OF THE MOON SELECTED TOPICS CONCERNING LUNAR EXPLORATION Edited by George C. ‘Bucker and Henry E. Siern George C. Marsball Space Flight Center Hzmtsville, A Za: NATIONAL AERONAUTICSAND SPACEADMINISTRATION - WASHINGTON;D. C. TECH LIBRARY KAFB. NM llL5475b NASA TN D-2944 PHYSICS OF THE MOON SELECTED TOPICS CONCERNING LUNAR EXPLORATION Edited by George C. Bucher and Henry E. Stern George C. Marshall Space Flight Center Huntsville, Ala. NATIONAL AERONAUTICS AND SPACE ADMINISTRATION For sole by the Clearinghouse for Federal Scientific and Technical information Springfield, Virginia 22151 - Price 56.00 I - TABLE OF CONTENTS Page SUMMA=. 1 INTRODUCTION. i SECTION I. CHARACTERISTICS OF THE MOON. i . 3 Chapter 1. The Moon’s .History, by Ernst Stuhlinger. 5 Chapter 2. Physical Characteristics of the Lunar Surface, by John Bensko . 39 Chapter 3. The’ Lunar Atmosphere, by Spencer G. Frary . , 55 Chapter 4. Energetic Radiation Environment of the Moon, by Martin 0. Burrell . 65 Chapter 5. The Lunar Thermal Environment , . 9i The Thermal Model of the Moon, by Gerhard B. Heller . 91 p Thermal Properties of the Moon as a Conductor of Heat,byBillyP. Jones.. 121 Infrared Methods of Measuring the Moon’s Temperature, by Charles D. Cochran. 135 SECTION II. EXPLORATION OF THE MOON . .I59 Chapter I. A Lunar Scientific Mission, by Daniel Payne Hale. 161 Chapter 2. Some Suggested Landing Sites for Exploration of the Moon, by Daniel Payne Hale. 177 Chapter 3. Environmental Control for Early Lunar Missions, by ‘Herman P. Gierow and James A. Downey, III . , . .2i I Chapter 4.
    [Show full text]
  • A GEOMORPHIC ANALYSIS of HALE CRATER, MARS: the EFFECTS of IMPACT INTO ICE-RICH CRUST By
    A GEOMORPHIC ANALYSIS OF HALE CRATER, MARS: THE EFFECTS OF IMPACT INTO ICE-RICH CRUST by Andrea Jean Philippoff Jones A Thesis Submitted to the Faculty of the DEPARTMENT OF GEOSCIENCES In Partial Fulfillment of the Requirements for the Degree of MASTER OF SCIENCE In the Graduate College THE UNIVERSITY OF ARIZONA 2009 1 A geomorphic analysis of Hale crater, Mars: the effects of impact into ice-rich crust A. P. Jonesa,* A. S. McEwenb L. L. Tornabeneb D. C. Bermanc V. R. Bakerd H. J. Meloshb aDepartment of Geosciences, University of Arizona, Tucson AZ, 85721 *Corresponding author ([email protected]) bLunar and Planetary Laboratory, University of Arizona, Tucson AZ, 85721 cPlanetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson AZ, 85719 dDepartment of Hydrology and Water Resources, University of Arizona, Tucson AZ, 85721 56 Pages 19 Figures 1 Table 2 Proposed running head: A geomorphic analysis of Hale Crater, Mars Abstract Hale crater, a 125 × 150 km impact crater located at the intersection of Uzboi Vallis and the northern rim of Argyre basin at 323.6ºE, 35.7ºS, is surrounded by channels that radiate from, incise into, and transport material within its ejecta blanket. The spatial and temporal relationship between the channels and Hale’s ejecta strongly suggests the impact event created or modified the channels and emplaced fluidized debris flow lobes over an extensive area (>200,000 km2). We estimate ~1010 m3 of liquid water was required to form some of Hale’s smaller channels, a volume we propose was supplied by subsurface ice melted and mobilized by the Hale-forming impact.
    [Show full text]
  • A Geomorphic Analysis of Hale Crater, Mars: the Effects of Impact Into Ice-Rich Crust ⇑ A.P
    Icarus 211 (2011) 259–272 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus A geomorphic analysis of Hale crater, Mars: The effects of impact into ice-rich crust ⇑ A.P. Jones a, , A.S. McEwen b, L.L. Tornabene b,1, V.R. Baker c, H.J. Melosh d, D.C. Berman e a Department of Geosciences, University of Arizona, Tucson, AZ 85721, United States b Lunar and Planetary Laboratory, University of Arizona, Tucson, AZ 85721, United States c Department of Hydrology and Water Resources, University of Arizona, Tucson, AZ 85721, United States d Department of Earth and Atmospheric Sciences, Purdue University, West Lafayette, IN 47907, United States e Planetary Science Institute, 1700 East Fort Lowell Road, Suite 106, Tucson, AZ 85719, United States article info abstract Article history: Hale crater, a 125 Â 150 km impact crater located near the intersection of Uzboi Vallis and the northern Received 23 April 2010 rim of Argyre basin at 35.7°S, 323.6°E, is surrounded by channels that radiate from, incise, and transport Revised 13 October 2010 material within Hale’s ejecta. The spatial and temporal relationship between the channels and Hale’s Accepted 15 October 2010 ejecta strongly suggests the impact event created or modified the channels and emplaced fluidized debris Available online 29 October 2010 flow lobes over an extensive area (>200,000 km2). We estimate 1010 m3 of liquid water was required to form some of Hale’s smaller channels, a volume we propose was supplied by subsurface ice melted and Keywords: mobilized by the Hale-forming impact.
    [Show full text]
  • Physical Properties of Lunar Craters
    RAA 2017 Vol. 17 No. 3, 24 (16pp) doi: 10.1088/1674–4527/17/3/24 R c 2017 National Astronomical Observatories, CAS and IOP Publishing Ltd. esearch in Astronomy and http://www.raa-journal.org http://iopscience.iop.org/raa Astrophysics Physical properties of lunar craters Maitri P. Joshi, Kushal P. Bhatt and Rajmal Jain Shri Maneklal M. Patel Institute of Sciences and Research, Kadi Sarva Vishwavidhyalaya, Gandhinagar - 382015, India; rajmal [email protected] Received 2016 August 11; accepted 2016 November 25 Abstract The surface of the Moon is highly cratered due to impacts of meteorites, asteroids, comets and other celestial objects. The origin, size, structure, age and composition vary among craters. We study a total of 339 craters observed by the Lunar Reconnaissance Orbiter Camera (LROC). Out of these 339 craters, 214 craters are known (named craters included in the IAU Gazetteer of Planetary Nomenclature) and 125 craters are unknown (craters that are not named and objects that are absent in the IAU Gazetteer). We employ images taken by LROC at the North and South Poles and near side of the Moon. We report for the first time the study of unknown craters, while we also review the study of known craters conducted earlier by previous researchers. Our study is focused on measurements of diameter, depth, latitude and longitude of each crater for both known and unknown craters. The diameter measurements are based on considering the Moon to be a spherical body. The LROC website also provides a plot which enables us to measure the depth and diameter.
    [Show full text]
  • Lunar Reconnaissance Orbiter Camera (LROC) Instrument Overview
    Space Sci Rev (2010) 150: 81–124 DOI 10.1007/s11214-010-9634-2 Lunar Reconnaissance Orbiter Camera (LROC) Instrument Overview M.S. Robinson · S.M. Brylow · M. Tschimmel · D. Humm · S.J. Lawrence · P.C. Thomas · B.W. Denevi · E. Bowman-Cisneros · J. Zerr · M.A. Ravine · M.A. Caplinger · F.T. Ghaemi · J.A. Schaffner · M.C. Malin · P. Mahanti · A. Bartels · J. Anderson · T.N. Tran · E.M. Eliason · A.S. McEwen · E. Turtle · B.L. Jolliff · H. Hiesinger Received: 22 June 2009 / Accepted: 2 February 2010 / Published online: 11 March 2010 © Springer Science+Business Media B.V. 2010 Abstract The Lunar Reconnaissance Orbiter Camera (LROC) Wide Angle Camera (WAC) and Narrow Angle Cameras (NACs) are on the NASA Lunar Reconnaissance Orbiter (LRO). M.S. Robinson () · M. Tschimmel · S.J. Lawrence · B.W. Denevi · E. Bowman-Cisneros · P. Mahanti · T.N. Tran School of Earth and Space Exploration, Arizona State University, Tempe, AZ, USA e-mail: [email protected] S.M. Brylow · J. Zerr · M.A. Ravine · M.A. Caplinger · J.A. Schaffner · M.C. Malin Malin Space Science Systems, San Diego, CA, USA D. Humm Space Instrument Calibration Consulting, Annapolis, MD, USA P.C. Thomas Center for Radiophysics and Space Research, Cornell University, Ithaca, NY, USA A. Bartels National Aeronautics and Space Administration, Goddard Space Flight Center, Greenbelt, MD, USA J. Anderson Astrogeology Branch, United States Geological Survey, Flagstaff, AZ, USA F.T. Ghaemi Tony Ghaemi Optical Engineering, San Diego, CA, USA E.M. Eliason · A.S. McEwen Lunar and Planetary Lab, University of Arizona, Tucson, AZ, USA E.
    [Show full text]