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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. -
Workshop on Geology of the Apollo 17 Landing Site
NASA-CR-191637 \ WORKSHOP ON GEOLOGY OF THE APOLLO 17 LANDING SITE (NASA-CR-191637) WORKSHOP ON N93-18786 GEOLOGY OF THE APOLLO 17 LANDING --THRU-- SITE (Lunar Science Inst.) 70 p N93-18817 Unclas G3/91 0141290 __ LPI Technical Report Number 92-09, Part 1 LUNAR AND PLANETARY INSTITUTE 3600 BAY AREA BOULEVARD HOUSTON TX 77058-1113 LPI/TR--92-09, Part 1 WORKSHOP ON GEOLOGY OF THE APOLLO 17 LANDING SITE Edited by G. Ryder, H. H. Schmitt, and P. D. Spudis Held at Houston, Texas December 2-4, 1992 Sponsored by Lunar and Planetary Sample Team Lunar and Planetary Institute Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 LPI Technical Report Number 92-09, Part 1 LPI/TR--92-09, Part 1 Compiledin 1992by LUNAR AND PLANETARY INSTITUTE TheInstituteis operatedby theUniversitySpaceResearchAssociationunderContractNo. NASW- 4574with theNationalAeronauticsandSpaceAdministration. Materialin this volume may be copied without restraint for library, abstract service, education, or per- sonal research purposes; however, republication of any paper or portion thereof requires the written permission of the authors as well as the appropriate acknowledgment of this publication. This report may be cited as Ryder G., Schmitt H. H., and Spudis P. D., eds. (1992) Workshop on Geology of the Apollo 17 Landing Site. LPI Tech. Rpt. 92-09, Part 1, Lunar and Planetary Institute, Houston. 63 pp. This report is distributed by ORDER DEPARTMENT Lunar and Planetary Institute 3600 Bay Area Boulevard Houston TX 77058-1113 Mail order requestors will be invoiced for the cost of shipping and handling. Cover: Station 4 at Taurus-LiUrow, Apollo 17 landing site. -
Lunar Cold Spots and Crater Production on the Moon 10.1029/2018JE005652 J.-P
Journal of Geophysical Research: Planets RESEARCH ARTICLE Lunar Cold Spots and Crater Production on the Moon 10.1029/2018JE005652 J.-P. Williams1 , J. L. Bandfield2 , D. A. Paige1, T. M. Powell1, B. T. Greenhagen3, S. Taylor1, 4 5 6 7,8 Key Points: P. O. Hayne , E. J. Speyerer , R. R. Ghent , and E. S. Costello • We measure diameters of craters 1 2 associated with cold spots. Their Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA, USA, Space Science Institute, Boulder, CO, USA, size-frequency distribution indicates 3Applied Physics Laboratory, Johns Hopkins University, Laurel, MD, USA, 4Department of Astrophysical & Planetary Sciences, cold spots survive a few hundred kyr University of Colorado, Boulder, Boulder, CO, USA, 5School of Earth and Space Exploration, Arizona State University, Tempe, AZ, • fl The distribution of cold spots re ects USA, 6Earth Sciences, University of Toronto, Toronto, ON, Canada, 7Department of Geology and Geophysics, University of ’ the Moon s synchronous rotation ’ ā 8 with cold spots focused on the apex Hawai iatM noa, Honolulu, HI, USA, Hawaii Institute of Geophysics and Planetology, Honolulu, HI, USA of motion • The largest cold spots with source craters larger than 800 m are Abstract Mapping of lunar nighttime surface temperatures has revealed anomalously low nighttime concentrated on the trailing side of temperatures around recently formed impact craters on the Moon. The thermophysically distinct “cold the moon spots” provide a way of identifying the most recently formed impact craters. Over 2,000 cold spot source craters were measured with diameters ranging from 43 m to 2.3 km. -
Recent Extensional Tectonics on the Moon Revealed by the Lunar Reconnaissance Orbiter Camera Thomas R
LETTERS PUBLISHED ONLINE: 19 FEBRUARY 2012 | DOI: 10.1038/NGEO1387 Recent extensional tectonics on the Moon revealed by the Lunar Reconnaissance Orbiter Camera Thomas R. Watters1*, Mark S. Robinson2, Maria E. Banks1, Thanh Tran2 and Brett W. Denevi3 Large-scale expressions of lunar tectonics—contractional of the Pasteur scarp (∼8:6◦ S, 100:6◦ E; Supplementary Fig. S1) are wrinkle ridges and extensional rilles or graben—are directly ∼1:2 km from the scarp face (Fig. 1b). Unlike the Madler graben, related to stresses induced by mare basalt-filled basins1,2. the orientation of the Pasteur graben are subparallel to the scarp and Basin-related extensional tectonic activity ceased about extend for ∼1:5 km, with the largest ∼300 m in length and 20–30 m 3.6 Gyr ago, whereas contractional tectonics continued until wide (Supplementary Note S3). about 1.2 Gyr ago2. In the lunar highlands, relatively young Lunar graben not located in the proximal back-limb terrain contractional lobate scarps, less than 1 Gyr in age, were first of lobate scarps have also been revealed in LROC NAC images. identified in Apollo-era photographs3. However, no evidence Graben found in the floor of Seares crater (∼74:7◦ N, 148:0◦ E; of extensional landforms was found beyond the influence of Supplementary Fig. S1) occur in the inter-scarp area of a cluster of mare basalt-filled basins and floor-fractured craters. Here seven lobate scarps (Fig. 1c). These graben are found over an area we identify previously undetected small-scale graben in the <1 km2 and have dimensions comparable to those in back-scarp farside highlands and in the mare basalts in images from the terrain, ∼150–250 m in length and with maximum widths of Lunar Reconnaissance Orbiter Camera. -
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. -
Geoscience and a Lunar Base a Comprehensive Plan for Lunar Exploration
NASA Conference Publication 3070 Geoscience and a Lunar Base A Comprehensive Plan for Lunar Exploration Edited by G. Jeffrey Taylor Institute of Meteoritics University of New Mexico Albuquerque, New Mexico Paul D. Spudis U.S. Geological Survey Branch of Astrogeology Flagstaff, Arizona Proceedings of a workshop sponsored by the National Aeronautics and Space Administration, Washington, D.C., and held at the Lunar and Planetary Institute Houston, Texas August 25-26, 1988 N/\S/\ National Aeronautics and Space Administration Office of Management Scientific and Technical Information Division 1990 PREFACE This report was produced at the request of Dr. Michael B. Duke, Director of the Solar System Exploration Division of the NASA Johnson Space Center. At a meeting of the Lunar and Planetary Sample Team (LAPST), Dr. Duke (at the time also Science Director of the Office of Exploration, NASA Headquarters) suggested that future lunar geoscience activities had not been planned systematically and that geoscience goals for the lunar base program were not articulated well. LAPST is a panel that advises NASA on lunar sample allocations and also serves as an advocate for lunar science within the planetary science community. LAPST took it upon itself to organize some formal geoscience planning for a lunar base by creating a document that outlines the types of missions and activities that are needed to understand the Moon and its geologic history. The committee wrote a draft of the report between February and June, 1988, with the help of two other scientists (listed below) and then organized a workshop to gather the thoughts and opinions of a broad spectrum of lunar scientists on the science opportunities and technical challenges posed by a lunar base program. -
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. -
Science Concept 2: the Structure and Composition of the Lunar Interior Provide Fundamental Information on the Evolution of a Differentiated Planetary Body
Science Concept 2: The Structure and Composition of the Lunar Interior Provide Fundamental Information on the Evolution of a Differentiated Planetary Body Science Concept 2: The Structure and Composition of the Lunar Interior Provide Fundamental Information on the Evolution of a Differentiated Planetary Body Science Goals: a. Determine the thickness of the lunar crust (upper and lower) and characterize its lateral variability on regional and global scales. b. Characterize the chemical/physical stratification in the mantle, particularly the nature of the putative 500-km discontinuity and the composition of the lower mantle. c. Determine the size, composition, and state (solid/liquid) of the core of the Moon. d. Characterize the thermal state of the interior and elucidate the workings of the planetary heat engine. INTRODUCTION Each of the Science Goals addressed by Science Concept 2 is linked: data regarding the crust, mantle, and core must be obtained in order to understand the thermal state of the interior and the planetary heat engine. Much about these Science Goals is currently unknown: crustal thickness and lateral variability are constrained by gravity and seismic models which suffer from non-uniqueness and a lack of control points; mantle composition is ambiguously estimated from seismic velocity profiles and assumed lunar bulk compositions; mantle structure is obtained through seismic velocity profiles, but fine-scale structure is not resolved and any structure outside the Apollo network and below 1000 kilometers depth is unknown; the size, composition and state of the core are obtained through models with few constraints, where the size and state are dependent on an unknown composition, making any core characteristic estimates highly variable; and the thermal state of the interior is constrained by heat flow measurements and characteristics of the core, but current heat flow data are not representative of the global heat flux and core models are non-unique. -
The Bombardment History of the Moon and the Origin of Life on Earth
The Bombardment History of the Moon and the Origin of Life on Earth Charles H. Lineweaver Marc Norman Planetary Science Institute Planetary Science Institute Research School of Earth Sciences and the Research School of Earth Sciences Research School of Astronomy and Astrophysics Australian National University Australian National University Canberra, Australia and Canberra, Australia Lunar and Planetary Science Institute Email: [email protected] 3600 Bay Area Boulevard Houston, TX 77058 USA Abstract—Life on Earth probably evolved between the Moon- forming impact ∼ 4:5 billion years ago and the earliest evidence for life on Earth ∼ 3:8 billion years ago. Whether the heavy bombardment of the Earth during this period frustrated or promoted the origin of life is uncertain. However, estimates of the extent and importance of the role of bombardment could be improved if we had better contraints on the time-dependence of the bombardment, and specifically on whether there was a spike in the bombardment rate ∼ 3:85 billion years ago. We review the evidence in the on-going debate about the existence and extent of such a spike, or late heavy bombardment (LHB). We briefly summarize our analysis of the crater counts in the oldest lunar basins and explain why our analysis does not support the LHB hypothesis. We also describe how corrections for saturation effects, undetected old basins and the assumption of constant impact rates made in our analysis, all have the effect of making the case against the LHB more robust. I. PLANETARY ACCRETION ! EARLY BOMBARDMENT ! LATE BOMBARDMENT? ! LIFE The Sun, like other stars, formed during the collapse of an over-dense clump in a molecular cloud in the plane of the Galaxy. -
Image Map of the Moon
U.S. Department of the Interior Prepared for the Scientific Investigations Map 3316 U.S. Geological Survey National Aeronautics and Space Administration Sheet 1 of 2 180° 0° 5555°° –55° Rowland 150°E MAP DESCRIPTION used for printing. However, some selected well-known features less that 85 km in diameter or 30°E 210°E length were included. For a complete list of the IAU-approved nomenclature for the Moon, see the This image mosaic is based on data from the Lunar Reconnaissance Orbiter Wide Angle 330°E 6060°° Gazetteer of Planetary Nomenclature at http://planetarynames.wr.usgs.gov. For lunar mission C l a v i u s –60°–60˚ Camera (WAC; Robinson and others, 2010), an instrument on the National Aeronautics and names, only successful landers are shown, not impactors or expended orbiters. Space Administration (NASA) Lunar Reconnaissance Orbiter (LRO) spacecraft (Tooley and others, 2010). The WAC is a seven band (321 nanometers [nm], 360 nm, 415 nm, 566 nm, 604 nm, 643 nm, and 689 nm) push frame imager with a 90° field of view in monochrome mode, and ACKNOWLEDGMENTS B i r k h o f f Emden 60° field of view in color mode. From the nominal 50-kilometer (km) polar orbit, the WAC This map was made possible with thanks to NASA, the LRO mission, and the Lunar Recon- Scheiner Avogadro acquires images with a 57-km swath-width and a typical length of 105 km. At nadir, the pixel naissance Orbiter Camera team. The map was funded by NASA's Planetary Geology and Geophys- scale for the visible filters (415–689 nm) is 75 meters (Speyerer and others, 2011). -
Small-Scale Lunar Graben: Distribution, Dimensions, and Formation Processes ⇑ Renee A
Icarus 252 (2015) 95–106 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Small-scale lunar graben: Distribution, dimensions, and formation processes ⇑ Renee A. French a, , Craig R. Bina a, Mark S. Robinson b, Thomas R. Watters c a Northwestern University, Department of Earth and Planetary Sciences, 2145 Sheridan Rd, Evanston, IL 60208-3130, USA b Arizona State University, School of Earth and Space Exploration, Tempe, AZ 85287, USA c Smithsonian Institute, National Air and Space Museum, Center for Earth and Planetary Studies, Washington, DC 20013, USA article info abstract Article history: The Lunar Reconnaissance Orbiter Camera (LROC) is the first instrument to provide widespread coverage Received 14 August 2014 with a range of incidence angles at the resolution required to detect small-scale landforms. A sample Revised 4 November 2014 (n = 238) of globally distributed, small-scale graben average 26 m wide and 179 m long. When dividing Accepted 28 December 2014 the population into those located within mare and highland regions, we observe that graben located Available online 10 January 2015 within mare tend to be narrower, shorter, and more irregularly spaced than those in highland terrane. For graben associated with contractional landforms, those in mare are smaller in width and length than Keywords: those in highlands; the same is true for graben independent of contractional landforms. Assuming a sim- Moon ple geometry, widths of mare graben associated with scarps or ridges are used to estimate the minimum Tectonics Moon, surface depth range to a mechanical discontinuity (e.g., base of the regolith) resulting in values of 4–48 m. -
Lunar Sourcebook : a User's Guide to the Moon
10 GLOBAL AND REGIONAL DATA ABOUT THE MOON Paul Spudis and Carlé Pieters Despite the major achievements in studying the it has been possible, with only a few landings and Moon during the last quarter-century, our global sample returns, to establish the outlines of the knowledge is still patchy and incomplete. Although Moon’s origin and development and to identify the the Moon is so close, access has always been limited. new scientific questions to be answered by future Half of the Moon remained completely unknown until missions. spacecraft could be sent around it. Even with the The next step in lunar studies is to acquire complete Apollo program and the Soviet and U.S. robotic lunar global information. It is paradoxical that the Apollo explorations, humans have directly explored only 6 program, which provided so much information about sites on the Moon and soft-landed robots at another a few parts of the Moon, did not also produce full 10 (not counting the Surveyor 3 site, which was also global data about such key lunar characteristics as visited by the Apollo 12 mission; see Table 2.1 and surface chemistry, surface mineral composition, Figs. 2.1 and 2.2). These sites are all on the lunar gravity, magnetic fields, and topography—in short, a nearside, and most of them are near the lunar scientific database for the whole Moon as a single equator. Sample return missions (both human and world. robotic) have provided information on only nine sites; The need for more global lunar data is clear, and so even with the addition of Antarctic lunar meteorites is the method necessary to collect it—a polar-orbiting (whose exact sources are unknown), the lunar spacecraft, equipped with an array of scientific sampling grid is still minimal.