Global Variations in Regolith Properties on Asteroid Vesta from Dawnï
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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]. -
June 9, 2020 LIST of ABSENTEE VOTERS HOLDING BALLOTS – NAMES
WARSAW CENTRAL SCHOOL BUDGET/BOARD VOTE – June 9, 2020 LIST OF ABSENTEE VOTERS HOLDING BALLOTS – NAMES Abbasey, Salman Aumer, Andrew J. Bauer, James E. Abbott, John Axtell, Paula A. Bauer, Janet M. Ackerman, James Backlas, Frederick A. Jr Bauer, Michael Ackerman, Susan M. Bagg , Robert L. Bauer, Michelle Adolf, Jeremy J. Bagg, Kenneth G. Baxter, Susan Agrawal, Rajendra Bagg, Patty Bayliss, Bruce A. Aguado, Andrew E. Bagley, Raymond F. Bayoumi, Ahmed Ahl, Florence Bailey, Betty J. Beach, Douglas A. Aker, James D. Bailey, Judith L. Beach, Robert L. Akin, Claudia J. Bailey, Lyndsay Beals, Duane M. Alband, Jeffrey L. Bailey, Richard L. Beals, Shane Alcaraz, Christina M. Bailey, Stephen Beardsley, Peter G. Alderson, Donald P. Bailey, Stephen Beck, Michael J. Aldinger, Suzanne Bailey, Tara L. Beckstrand, Benjamine C. Aldrich, Heather L. Baize, Mary A. Beckstrand, Denise C. Aldrich, Jordan A. Baker, Arlene W. Beilein, Paul T. Aldrich, Kathryn J. Baker, Charles O. Beinhauer, Joseph F. Alexander, Christopher J. Baker, Frederic Belden, Barbara A. Alexander, Tara Baker, Gregory S. Belden, James C. Allen, Patricia A. Baker, Karen Bell, David K. Allison, Eddie R. Baker, Kirk E. Bell, Kathleen D. Almeter, David J Baker, Kristina Bell, Lorraine F. Almeter, George Anna Baker, Nichlos Bell, Milda Almeter, Nathan A. Baker, Peggy J. Bell, Mildred E. Almeter, Steven A. Baker, Roger O. Bellaire, Donald Ames, Gregory K. Baker, Shawn R. Bellaire, Donald W. Sr Ames, Richard A. Bakowski, Christopher Belles, Cody J. Andalora, Ingeburg Ballard, Joanne R. Bellinger, Heather Andalora, Orah Ballerstein, Lisa Bender, Gloria Andrews, Lee H. Ballew, Marjorie Bender, Sidney Antinore, Hope Bannister, Jeffrey H. -
Testing Hypotheses for the Origin of Steep Slope of Lunar Size-Frequency Distribution for Small Craters
CORE Metadata, citation and similar papers at core.ac.uk Provided by Springer - Publisher Connector Earth Planets Space, 55, 39–51, 2003 Testing hypotheses for the origin of steep slope of lunar size-frequency distribution for small craters Noriyuki Namiki1 and Chikatoshi Honda2 1Department of Earth and Planetary Sciences, Kyushu University, Hakozaki 6-10-1, Higashi-ku, Fukuoka 812-8581, Japan 2The Institute of Space and Astronautical Science, Yoshinodai 3-1-1, Sagamihara 229-8510, Japan (Received June 13, 2001; Revised June 24, 2002; Accepted January 6, 2003) The crater size-frequency distribution of lunar maria is characterized by the change in slope of the population between 0.3 and 4 km in crater diameter. The origin of the steep segment in the distribution is not well understood. Nonetheless, craters smaller than a few km in diameter are widely used to estimate the crater retention age for areas so small that the number of larger craters is statistically insufficient. Future missions to the moon, which will obtain high resolution images, will provide a new, large data set of small craters. Thus it is important to review current hypotheses for their distributions before future missions are launched. We examine previous and new arguments and data bearing on the admixture of endogenic and secondary craters, horizontal heterogeneity of the substratum, and the size-frequency distribution of the primary production function. The endogenic crater and heterogeneous substratum hypotheses are seen to have little evidence in their favor, and can be eliminated. The primary production hypothesis fails to explain a wide variation of the size-frequency distribution of Apollo panoramic photographs. -
August 2017 Posidonius P & Luther
A PUBLICATION OF THE LUNAR SECTION OF THE A.L.P.O. EDITED BY: Wayne Bailey [email protected] 17 Autumn Lane, Sewell, NJ 08080 RECENT BACK ISSUES: http://moon.scopesandscapes.com/tlo_back.html FEATURE OF THE MONTH – AUGUST 2017 POSIDONIUS P & LUTHER Sketch and text by Robert H. Hays, Jr. - Worth, Illinois, USA March 5, 2017 01:28-01:48; UT, 15 cm refl, 170x, seeing 7-8/10. I drew these craters on the evening of March 4/5, 2017 while the moon was hiding some Hyades stars. This area is in northeast Mare Serenitatis west of Posidonius itself. Posidonius P is the largest crater on this sketch. The smaller crater south of P is Posidonius F and Posidonius G is the tiny pit to the north. There is a halo around Posidonius G, but this crater is noticeably north of the halo's center. A very low round swelling is northeast of Posidonius G. Luther is the crater well to the west of Posidonius P. All four of these craters are crisp, symmetric features, differing only in size. There are an assortment of elevations near Luther. The peak Luther alpha is well to the west of Luther, and showed dark shadowing at this time. All of the other features near Luther are more subtle than Luther alpha. One mound is between Luther and Luther alpha. Two more mounds are north of Luther, and a low ridge is just east of this crater. A pair of very low mounds are south of Luther. These are the vaguest features depicted here, and may be too conspicuous on the sketch. -
Compositional and Mineralogical Characteristics of Archimedes Crater Region Using Chandrayaan – 1 M3 Data
50th Lunar and Planetary Science Conference 2019 (LPI Contrib. No. 2132) 1040.pdf COMPOSITIONAL AND MINERALOGICAL CHARACTERISTICS OF ARCHIMEDES CRATER REGION USING CHANDRAYAAN – 1 M3 DATA. P. R. Kumaresan1 and J. Saravanavel2, 1Research Scholar, 2Assistant Professor, Department of Remote Sensing, Bharathidasan University, Tiruchirappalli-23, Tamil Nadu, India, email: [email protected], [email protected] Introduction: The Earth’s natural satellite the tometry corrected reflectance data captured during the moon is nearest celestial body appears brightest object OP1B optical period. in our night sky. Moon surfaces are composed of dark and light areas. The dark areas are called Maria which is made up of basaltic terrain and light areas are high- lands mostly made up of Anorthositic rocks. The moon surface is littered with craters, which are formed when meteors hit its surface. To understand the evolution, geological process of the moon it is important to study the surface composition and minerals present in crustal surface. In this regard, in our study, we have attempted to map the minerals and surface composition of Archi- medes crater region. Study area: Archimedes crater is a large impact crater located on the eastern edges of the Mare Imbri- um of near side moon (29.7° N, 4.0° W). The diameter of the crater is 83 km with smooth floor flooded (1) with mare basalt and lack of a central peak. The rim (2) has a significant outer rampart brightened with ejecta (3) and the some portion of a terraced inner wall. Ar- chimedes Crater is named for the Greek mathematician Archimedes, who made many mathematical discoveries in the 200 B.C [1, 2]. -
A Study About the Temporal Constraints on the Martian Yardangs’ Development in Medusae Fossae Formation
remote sensing Article A Study about the Temporal Constraints on the Martian Yardangs’ Development in Medusae Fossae Formation Jia Liu 1,2 , Zongyu Yue 1,3,*, Kaichang Di 1,3 , Sheng Gou 1,4 and Shengli Niu 4 1 State Key Laboratory of Remote Sensing Science, Aerospace Information Research Institute, Chinese Academy of Sciences, Beijing 100101, China; [email protected] (J.L.); [email protected] (K.D.); [email protected] (S.G.) 2 University of Chinese Academy of Sciences, Beijing 100049, China 3 CAS Center for Excellence in Comparative Planetology, Hefei 230026, China 4 State Key Laboratory of Lunar and Planetary Sciences, Macau University of Science and Technology, Macau 999078, China; [email protected] * Correspondence: [email protected]; Tel.: +86-10-64889553 Abstract: The age of Mars yardangs is significant in studying their development and the evolution of paleoclimate conditions. For planetary surface or landforms, a common method for dating is based on the frequency and size distribution of all the superposed craters after they are formed. However, there is usually a long duration for the yardangs’ formation, and they will alter the superposed craters, making it impossible to give a reliable dating result with the method. An indirect method by analyzing the ages of the superposed layered ejecta was devised in the research. First, the layered ejecta that are superposed on and not altered by the yardangs are identified and mapped. Then, the ages of the layered ejecta are derived according to the crater frequency and size distribution on them. These ages indicate that the yardangs ceased development by these times, and the ages are valuable for studying the evolution of the yardangs. -
The Moon After Apollo
ICARUS 25, 495-537 (1975) The Moon after Apollo PAROUK EL-BAZ National Air and Space Museum, Smithsonian Institution, Washington, D.G- 20560 Received September 17, 1974 The Apollo missions have gradually increased our knowledge of the Moon's chemistry, age, and mode of formation of its surface features and materials. Apollo 11 and 12 landings proved that mare materials are volcanic rocks that were derived from deep-seated basaltic melts about 3.7 and 3.2 billion years ago, respec- tively. Later missions provided additional information on lunar mare basalts as well as the older, anorthositic, highland rocks. Data on the chemical make-up of returned samples were extended to larger areas of the Moon by orbiting geo- chemical experiments. These have also mapped inhomogeneities in lunar surface chemistry, including radioactive anomalies on both the near and far sides. Lunar samples and photographs indicate that the moon is a well-preserved museum of ancient impact scars. The crust of the Moon, which was formed about 4.6 billion years ago, was subjected to intensive metamorphism by large impacts. Although bombardment continues to the present day, the rate and size of impact- ing bodies were much greater in the first 0.7 billion years of the Moon's history. The last of the large, circular, multiringed basins occurred about 3.9 billion years ago. These basins, many of which show positive gravity anomalies (mascons), were flooded by volcanic basalts during a period of at least 600 million years. In addition to filling the circular basins, more so on the near side than on the far side, the basalts also covered lowlands and circum-basin troughs. -
Binary Asteroids and the Formation of Doublet Craters
ICARUS 124, 372±391 (1996) ARTICLE NO. 0215 Binary Asteroids and the Formation of Doublet Craters WILLIAM F. BOTTKE,JR. Division of Geological and Planetary Sciences, California Institute of Technology, Mail Code 170-25, Pasadena, California 91125 E-mail: [email protected] AND H. JAY MELOSH Lunar and Planetary Laboratory, University of Arizona, Tucson, Arizona 85721 Received April 29, 1996; revised August 14, 1996 found we could duplicate the observed fraction of doublet cra- At least 10% (3 out of 28) of the largest known impact craters ters found on Earth, Venus, and Mars. Our results suggest on Earth and a similar fraction of all impact structures on that any search for asteroid satellites should place emphasis Venus are doublets (i.e., have a companion crater nearby), on km-sized Earth-crossing asteroids with short-rotation formed by the nearly simultaneous impact of objects of compa- periods. 1996 Academic Press, Inc. rable size. Mars also has doublet craters, though the fraction found there is smaller (2%). These craters are too large and too far separated to have been formed by the tidal disruption 1. INTRODUCTION of an asteroid prior to impact, or from asteroid fragments dispersed by aerodynamic forces during entry. We propose that Two commonly held paradigms about asteroids and some fast rotating rubble-pile asteroids (e.g., 4769 Castalia), comets are that (a) they are composed of non-fragmented after experiencing a close approach with a planet, undergo tidal chunks of rock or rock/ice mixtures, and (b) they are soli- breakup and split into multiple co-orbiting fragments. -
Water on the Moon, III. Volatiles & Activity
Water on The Moon, III. Volatiles & Activity Arlin Crotts (Columbia University) For centuries some scientists have argued that there is activity on the Moon (or water, as recounted in Parts I & II), while others have thought the Moon is simply a dead, inactive world. [1] The question comes in several forms: is there a detectable atmosphere? Does the surface of the Moon change? What causes interior seismic activity? From a more modern viewpoint, we now know that as much carbon monoxide as water was excavated during the LCROSS impact, as detailed in Part I, and a comparable amount of other volatiles were found. At one time the Moon outgassed prodigious amounts of water and hydrogen in volcanic fire fountains, but released similar amounts of volatile sulfur (or SO2), and presumably large amounts of carbon dioxide or monoxide, if theory is to be believed. So water on the Moon is associated with other gases. Astronomers have agreed for centuries that there is no firm evidence for “weather” on the Moon visible from Earth, and little evidence of thick atmosphere. [2] How would one detect the Moon’s atmosphere from Earth? An obvious means is atmospheric refraction. As you watch the Sun set, its image is displaced by Earth’s atmospheric refraction at the horizon from the position it would have if there were no atmosphere, by roughly 0.6 degree (a bit more than the Sun’s angular diameter). On the Moon, any atmosphere would cause an analogous effect for a star passing behind the Moon during an occultation (multiplied by two since the light travels both into and out of the lunar atmosphere). -
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. -
Appendix I Lunar and Martian Nomenclature
APPENDIX I LUNAR AND MARTIAN NOMENCLATURE LUNAR AND MARTIAN NOMENCLATURE A large number of names of craters and other features on the Moon and Mars, were accepted by the IAU General Assemblies X (Moscow, 1958), XI (Berkeley, 1961), XII (Hamburg, 1964), XIV (Brighton, 1970), and XV (Sydney, 1973). The names were suggested by the appropriate IAU Commissions (16 and 17). In particular the Lunar names accepted at the XIVth and XVth General Assemblies were recommended by the 'Working Group on Lunar Nomenclature' under the Chairmanship of Dr D. H. Menzel. The Martian names were suggested by the 'Working Group on Martian Nomenclature' under the Chairmanship of Dr G. de Vaucouleurs. At the XVth General Assembly a new 'Working Group on Planetary System Nomenclature' was formed (Chairman: Dr P. M. Millman) comprising various Task Groups, one for each particular subject. For further references see: [AU Trans. X, 259-263, 1960; XIB, 236-238, 1962; Xlffi, 203-204, 1966; xnffi, 99-105, 1968; XIVB, 63, 129, 139, 1971; Space Sci. Rev. 12, 136-186, 1971. Because at the recent General Assemblies some small changes, or corrections, were made, the complete list of Lunar and Martian Topographic Features is published here. Table 1 Lunar Craters Abbe 58S,174E Balboa 19N,83W Abbot 6N,55E Baldet 54S, 151W Abel 34S,85E Balmer 20S,70E Abul Wafa 2N,ll7E Banachiewicz 5N,80E Adams 32S,69E Banting 26N,16E Aitken 17S,173E Barbier 248, 158E AI-Biruni 18N,93E Barnard 30S,86E Alden 24S, lllE Barringer 29S,151W Aldrin I.4N,22.1E Bartels 24N,90W Alekhin 68S,131W Becquerei