Martian Crater Morphology
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Curiosity's Candidate Field Site in Gale Crater, Mars
Curiosity’s Candidate Field Site in Gale Crater, Mars K. S. Edgett – 27 September 2010 Simulated view from Curiosity rover in landing ellipse looking toward the field area in Gale; made using MRO CTX stereopair images; no vertical exaggeration. The mound is ~15 km away 4th MSL Landing Site Workshop, 27–29 September 2010 in this view. Note that one would see Gale’s SW wall in the distant background if this were Edgett, 1 actually taken by the Mastcams on Mars. Gale Presents Perhaps the Thickest and Most Diverse Exposed Stratigraphic Section on Mars • Gale’s Mound appears to present the thickest and most diverse exposed stratigraphic section on Mars that we can hope access in this decade. • Mound has ~5 km of stratified rock. (That’s 3 miles!) • There is no evidence that volcanism ever occurred in Gale. • Mound materials were deposited as sediment. • Diverse materials are present. • Diverse events are recorded. – Episodes of sedimentation and lithification and diagenesis. – Episodes of erosion, transport, and re-deposition of mound materials. 4th MSL Landing Site Workshop, 27–29 September 2010 Edgett, 2 Gale is at ~5°S on the “north-south dichotomy boundary” in the Aeolis and Nepenthes Mensae Region base map made by MSSS for National Geographic (February 2001); from MOC wide angle images and MOLA topography 4th MSL Landing Site Workshop, 27–29 September 2010 Edgett, 3 Proposed MSL Field Site In Gale Crater Landing ellipse - very low elevation (–4.5 km) - shown here as 25 x 20 km - alluvium from crater walls - drive to mound Anderson & Bell -
Template for Two-Page Abstracts in Word 97 (PC)
GEOLOGIC MAPPING OF THE LUNAR SOUTH POLE QUADRANGLE (LQ-30). S.C. Mest1,2, D.C. Ber- man1, and N.E. Petro2, 1Planetary Science Institute, 1700 E. Ft. Lowell, Suite 106, Tucson, AZ 85719-2395 ([email protected]); 2Planetary Geodynamics Laboratory, Code 698, NASA GSFC, Greenbelt, MD 20771. Introduction: In this study we use recent image, the surface [7]. Impact craters display morphologies spectral and topographic data to map the geology of the ranging from simple to complex [7-9,24] and most lunar South Pole quadrangle (LQ-30) at 1:2.5M scale contain floor deposits distinct from surrounding mate- [1-7]. The overall objective of this research is to con- rials. Most of these deposits likely consist of impact strain the geologic evolution of LQ-30 (60°-90°S, 0°- melt; however, some deposits, especially on the floors ±180°) with specific emphasis on evaluation of a) the of the larger craters and basins (e.g., Antoniadi), ex- regional effects of impact basin formation, and b) the hibit low albedo and smooth surfaces and may contain spatial distribution of ejecta, in particular resulting mare. Higher albedo deposits tend to contain a higher from formation of the South Pole-Aitken (SPA) basin density of superposed impact craters. and other large basins. Key scientific objectives in- Antoniadi Crater. Antoniadi crater (D=150 km; clude: 1) Determining the geologic history of LQ-30 69.5°S, 172°W) is unique for several reasons. First, and examining the spatial and temporal variability of Antoniadi is the only lunar crater that contains both a geologic processes within the map area. -
Identification of the Deepest Craters on Mars Based on the Preservation
IDENTIFCATION OF THE DEEPEST CRATERS ON MARS BASED ON THE PRESERVATION OF PITTED IMPACT MELT-BEARING DEPOSITS. L. L. Tornabene1,2, V. Ling3, J. M. Boyce4, G. R. Osinski1,5, T. N. Harrison1, and A. S. McEwen6, 1Dept. of Earth Sciences & Centre for Planetary Science and Exploration, Western University, London, ON, N6A 5B7, Canada ([email protected]), 2SETI Institute, Mountain View, CA 94043, USA, 3Central Secondary School, London, ON, N6B 2P8, Canada, 4Hawaii Institute of Geophysics and Planetology, University of Hawaii, Honolulu, HI 96822, USA, 5Dept. Physics & Astronomy, Western University, London, ON, N6A 5B7, Canada, 6Lunar and Planetary Laborato- ry, University of Arizona, Tucson, AZ 85721, USA. Introduction: Crater-related pitted materials, were avoided. As such, the lowest elevation on the thought to be impact melt-rich deposits formed from floor off the central pit was used instead. Likewise, any volatile-rich substrates, have been observed in high- overprinting primary or secondary impact craters on resolution images of both the youngest and best- the host crater floors were avoided – again, using the preserved craters on both Mars and Vesta [1–3]. To next lowest elevation that clearly fell on “unmodified” date, 205 such craters have been identified on Mars host crater floor. After plotting all the dr vs. D values, ranging from 1–150 km in diameter, and are randomly outliers (i.e., extremely deep or shallow craters) were distributed between ~60°S and 60°N latitudes [1]. assessed carefully with respect to pre-existing topogra- Because pitted materials likely represent the prima- phy and post-impact modification. Craters with uneven ry crater-fill deposits, and show a strong correlation or complex background terrains, or craters that over- with crater preservation [1–3], we explore their use to printed other craters, specifically in the vicinity of the reassess depth-to-Diameter (d/D) scaling relationship rim or the floor were noted, adjusted if possible or not using Mars Orbiter Laser Altimeter (MOLA) data. -
Extensional Tectonics in Tempe Terra 8 May 2006
Extensional tectonics in Tempe Terra 8 May 2006 Tectonic processes (extensional stresses, in this case) have led to the development of these grabens. After the tectonic activity, other processes reshaped the landscape. In the scene, the results of weathering and mass transport can be seen. Due to erosion, the surface has been smoothed, giving formerly sharp edges a rounded appearance. Such terrain is called "fretted terrain" and is characteristic for the transition of highland to lowland. The valleys and grabens are 5 to 10 kilometres wide and up to 1500 metres deep. Along the graben flanks, the layering of the bedrock is exposed. The lineations on the valley floors are attributed to a slow viscous movement of material, Extensional tectonics in Tempe Terra. presumably in connection with ice. These lineations and indications of possible ice underneath the surface lead scientists to assume that the structures are rock glaciers or similar phenomena These images, taken by the High Resolution known from alpine regions on Earth. Stereo Camera (HRSC) on board ESA's Mars Express spacecraft, show the tectonic 'grabens' in The stereo and colour capabilities, and the high- Tempe Terra, a geologically complex region that is resolution coverage of extended areas, provided by part of the old Martian highlands. the HRSC camera allow for improved study of the complex geologic evolution of the Red Planet. The The HRSC obtained these images during orbit Mars Express HRSC camera gives scientists the 1180 on 19 December 2004 with a ground opportunity to better understand the tectonics of resolution of approximately 16.5 metres per pixel. -
Glossary Glossary
Glossary Glossary Albedo A measure of an object’s reflectivity. A pure white reflecting surface has an albedo of 1.0 (100%). A pitch-black, nonreflecting surface has an albedo of 0.0. The Moon is a fairly dark object with a combined albedo of 0.07 (reflecting 7% of the sunlight that falls upon it). The albedo range of the lunar maria is between 0.05 and 0.08. The brighter highlands have an albedo range from 0.09 to 0.15. Anorthosite Rocks rich in the mineral feldspar, making up much of the Moon’s bright highland regions. Aperture The diameter of a telescope’s objective lens or primary mirror. Apogee The point in the Moon’s orbit where it is furthest from the Earth. At apogee, the Moon can reach a maximum distance of 406,700 km from the Earth. Apollo The manned lunar program of the United States. Between July 1969 and December 1972, six Apollo missions landed on the Moon, allowing a total of 12 astronauts to explore its surface. Asteroid A minor planet. A large solid body of rock in orbit around the Sun. Banded crater A crater that displays dusky linear tracts on its inner walls and/or floor. 250 Basalt A dark, fine-grained volcanic rock, low in silicon, with a low viscosity. Basaltic material fills many of the Moon’s major basins, especially on the near side. Glossary Basin A very large circular impact structure (usually comprising multiple concentric rings) that usually displays some degree of flooding with lava. The largest and most conspicuous lava- flooded basins on the Moon are found on the near side, and most are filled to their outer edges with mare basalts. -
Planetary Surfaces
Chapter 4 PLANETARY SURFACES 4.1 The Absence of Bedrock A striking and obvious observation is that at full Moon, the lunar surface is bright from limb to limb, with only limited darkening toward the edges. Since this effect is not consistent with the intensity of light reflected from a smooth sphere, pre-Apollo observers concluded that the upper surface was porous on a centimeter scale and had the properties of dust. The thickness of the dust layer was a critical question for landing on the surface. The general view was that a layer a few meters thick of rubble and dust from the meteorite bombardment covered the surface. Alternative views called for kilometer thicknesses of fine dust, filling the maria. The unmanned missions, notably Surveyor, resolved questions about the nature and bearing strength of the surface. However, a somewhat surprising feature of the lunar surface was the completeness of the mantle or blanket of debris. Bedrock exposures are extremely rare, the occurrence in the wall of Hadley Rille (Fig. 6.6) being the only one which was observed closely during the Apollo missions. Fragments of rock excavated during meteorite impact are, of course, common, and provided both samples and evidence of co,mpetent rock layers at shallow levels in the mare basins. Freshly exposed surface material (e.g., bright rays from craters such as Tycho) darken with time due mainly to the production of glass during micro- meteorite impacts. Since some magnetic anomalies correlate with unusually bright regions, the solar wind bombardment (which is strongly deflected by the magnetic anomalies) may also be responsible for darkening the surface [I]. -
Lexiconordica
LexicoNordica Forfatter: Hannu Tommola og Arto Mustajoki [Den förnyade rysk-finska storordboken] Anmeldt værk: Martti Kuusinen, Vera Ollikainen og Julia Syrjäläinen. 1997. Venäjä- suomi-suursanakirja (Bol ´šoj russko-finskij slovar´) yli 90.000 hakusanaa ja sanontaa. Porvoo/Helsinki/Juva: WSOY og Moskva: Russkij jazyk, 1997. Kilde: LexicoNordica 5, 1998, s. 239-260 URL: http://ojs.statsbiblioteket.dk/index.php/lexn/issue/archive © LexicoNordica og forfatterne Betingelser for brug af denne artikel Denne artikel er omfattet af ophavsretsloven, og der må citeres fra den. Følgende betingelser skal dog være opfyldt: Citatet skal være i overensstemmelse med „god skik“ Der må kun citeres „i det omfang, som betinges af formålet“ Ophavsmanden til teksten skal krediteres, og kilden skal angives, jf. ovenstående bibliografiske oplysninger. Søgbarhed Artiklerne i de ældre LexicoNordica (1-16) er skannet og OCR-behandlet. OCR står for ’optical character recognition’ og kan ved tegngenkendelse konvertere et billede til tekst. Dermed kan man søge i teksten. Imidlertid kan der opstå fejl i tegngenkendelsen, og når man søger på fx navne, skal man være forberedt på at søgningen ikke er 100 % pålidelig. 239 Hannu Tommola & Arto Mustajoki Den förnyade rysk-finska storordboken Martti Kuusinen, Vera Ollikainen, Julia Syrjäläinen: Venäjä-suomi- suursanakirja (Bol´soj russko-finskij slovar´) yli 90.000 hakusanaa ja sanontaa. Toim. M. Kuusinen. Porvoo, Helsinki, Juva: WSOY & Moskva: Russkij jazyk, 1997, XXXI + 1575 s. Pris: FIM 554. The dictionary reviewed in this article is a revised edition of a Russian-Finnish dictionary compiled by scholars in the former Soviet Karelia. The dictionary was first published in 1963 in Moscow, then reprinted twice by the Finnish publishing house WSOY. -
Widespread Crater-Related Pitted Materials on Mars: Further Evidence for the Role of Target Volatiles During the Impact Process ⇑ Livio L
Icarus 220 (2012) 348–368 Contents lists available at SciVerse ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Widespread crater-related pitted materials on Mars: Further evidence for the role of target volatiles during the impact process ⇑ Livio L. Tornabene a, , Gordon R. Osinski a, Alfred S. McEwen b, Joseph M. Boyce c, Veronica J. Bray b, Christy M. Caudill b, John A. Grant d, Christopher W. Hamilton e, Sarah Mattson b, Peter J. Mouginis-Mark c a University of Western Ontario, Centre for Planetary Science and Exploration, Earth Sciences, London, ON, Canada N6A 5B7 b University of Arizona, Lunar and Planetary Lab, Tucson, AZ 85721-0092, USA c University of Hawai’i, Hawai’i Institute of Geophysics and Planetology, Ma¯noa, HI 96822, USA d Smithsonian Institution, Center for Earth and Planetary Studies, Washington, DC 20013-7012, USA e NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA article info abstract Article history: Recently acquired high-resolution images of martian impact craters provide further evidence for the Received 28 August 2011 interaction between subsurface volatiles and the impact cratering process. A densely pitted crater-related Revised 29 April 2012 unit has been identified in images of 204 craters from the Mars Reconnaissance Orbiter. This sample of Accepted 9 May 2012 craters are nearly equally distributed between the two hemispheres, spanning from 53°Sto62°N latitude. Available online 24 May 2012 They range in diameter from 1 to 150 km, and are found at elevations between À5.5 to +5.2 km relative to the martian datum. The pits are polygonal to quasi-circular depressions that often occur in dense clus- Keywords: ters and range in size from 10 m to as large as 3 km. -
Sky and Telescope
SkyandTelescope.com The Lunar 100 By Charles A. Wood Just about every telescope user is familiar with French comet hunter Charles Messier's catalog of fuzzy objects. Messier's 18th-century listing of 109 galaxies, clusters, and nebulae contains some of the largest, brightest, and most visually interesting deep-sky treasures visible from the Northern Hemisphere. Little wonder that observing all the M objects is regarded as a virtual rite of passage for amateur astronomers. But the night sky offers an object that is larger, brighter, and more visually captivating than anything on Messier's list: the Moon. Yet many backyard astronomers never go beyond the astro-tourist stage to acquire the knowledge and understanding necessary to really appreciate what they're looking at, and how magnificent and amazing it truly is. Perhaps this is because after they identify a few of the Moon's most conspicuous features, many amateurs don't know where Many Lunar 100 selections are plainly visible in this image of the full Moon, while others require to look next. a more detailed view, different illumination, or favorable libration. North is up. S&T: Gary The Lunar 100 list is an attempt to provide Moon lovers with Seronik something akin to what deep-sky observers enjoy with the Messier catalog: a selection of telescopic sights to ignite interest and enhance understanding. Presented here is a selection of the Moon's 100 most interesting regions, craters, basins, mountains, rilles, and domes. I challenge observers to find and observe them all and, more important, to consider what each feature tells us about lunar and Earth history. -
Analysis of Polarimetric Mini-SAR and Mini-RF Datasets for Surface Characterization and Crater Delineation on Moon †
Proceeding Paper Analysis of Polarimetric Mini-SAR and Mini-RF Datasets for Surface Characterization and Crater Delineation on Moon † Himanshu Kumari and Ashutosh Bhardwaj * Photogrammetry and Remote Sensing Department, Indian Institute of Remote Sensing, Dehradun 248001, India; [email protected] * Correspondence: [email protected]; Tel.: +91-9410319433 † Presented at the 3rd International Electronic Conference on Atmospheric Sciences, 16–30 November 2020; Available online: https://ecas2020.sciforum.net/. Abstract: The hybrid polarimetric architecture of Mini-SAR and Mini-RF onboard Indian Chan- drayaan-1 and LRO missions were the first to acquire shadowed polar images of the Lunar surface. This study aimed to characterize the surface properties of Lunar polar and non-polar regions con- taining Haworth, Nobile, Gioja, an unnamed crater, Arago, and Moltke craters and delineate the crater boundaries using a newly emerged approach. The Terrain Mapping Camera (TMC) data of Chandrayaan-1 was found useful for the detection and extraction of precise boundaries of the cra- ters using the ArcGIS Crater tool. The Stokes child parameters estimated from radar backscatter like the degree of polarization (m), the relative phase (δ), Poincare ellipticity (χ) along with the Circular Polarization Ratio (CPR), and decomposition techniques, were used to study the surface attributes of craters. The Eigenvectors and Eigenvalues used to measure entropy and mean alpha showed distinct types of scattering, thus its comparison with m-δ, m-χ gave a profound conclusion to the lunar surface. The dominance of surface scattering confirmed the roughness of rugged material. The results showed the CPR associated with the presence of water ice as well as a dihedral reflection inside the polar craters. -
Impact Cratering
6 Impact cratering The dominant surface features of the Moon are approximately circular depressions, which may be designated by the general term craters … Solution of the origin of the lunar craters is fundamental to the unravel- ing of the history of the Moon and may shed much light on the history of the terrestrial planets as well. E. M. Shoemaker (1962) Impact craters are the dominant landform on the surface of the Moon, Mercury, and many satellites of the giant planets in the outer Solar System. The southern hemisphere of Mars is heavily affected by impact cratering. From a planetary perspective, the rarity or absence of impact craters on a planet’s surface is the exceptional state, one that needs further explanation, such as on the Earth, Io, or Europa. The process of impact cratering has touched every aspect of planetary evolution, from planetary accretion out of dust or planetesimals, to the course of biological evolution. The importance of impact cratering has been recognized only recently. E. M. Shoemaker (1928–1997), a geologist, was one of the irst to recognize the importance of this process and a major contributor to its elucidation. A few older geologists still resist the notion that important changes in the Earth’s structure and history are the consequences of extraterres- trial impact events. The decades of lunar and planetary exploration since 1970 have, how- ever, brought a new perspective into view, one in which it is clear that high-velocity impacts have, at one time or another, affected nearly every atom that is part of our planetary system. -
March 21–25, 2016
FORTY-SEVENTH LUNAR AND PLANETARY SCIENCE CONFERENCE PROGRAM OF TECHNICAL SESSIONS MARCH 21–25, 2016 The Woodlands Waterway Marriott Hotel and Convention Center The Woodlands, Texas INSTITUTIONAL SUPPORT Universities Space Research Association Lunar and Planetary Institute National Aeronautics and Space Administration CONFERENCE CO-CHAIRS Stephen Mackwell, Lunar and Planetary Institute Eileen Stansbery, NASA Johnson Space Center PROGRAM COMMITTEE CHAIRS David Draper, NASA Johnson Space Center Walter Kiefer, Lunar and Planetary Institute PROGRAM COMMITTEE P. Doug Archer, NASA Johnson Space Center Nicolas LeCorvec, Lunar and Planetary Institute Katherine Bermingham, University of Maryland Yo Matsubara, Smithsonian Institute Janice Bishop, SETI and NASA Ames Research Center Francis McCubbin, NASA Johnson Space Center Jeremy Boyce, University of California, Los Angeles Andrew Needham, Carnegie Institution of Washington Lisa Danielson, NASA Johnson Space Center Lan-Anh Nguyen, NASA Johnson Space Center Deepak Dhingra, University of Idaho Paul Niles, NASA Johnson Space Center Stephen Elardo, Carnegie Institution of Washington Dorothy Oehler, NASA Johnson Space Center Marc Fries, NASA Johnson Space Center D. Alex Patthoff, Jet Propulsion Laboratory Cyrena Goodrich, Lunar and Planetary Institute Elizabeth Rampe, Aerodyne Industries, Jacobs JETS at John Gruener, NASA Johnson Space Center NASA Johnson Space Center Justin Hagerty, U.S. Geological Survey Carol Raymond, Jet Propulsion Laboratory Lindsay Hays, Jet Propulsion Laboratory Paul Schenk,