The Scientific Context for Exploration of the Moon
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Thesis Yaxuedong Feb20141.Pdf
ABSTRACT The Water Vapor and Dust Plumes of Enceladus by Yaxue Dong Enceladus is the most active moon of Saturn. Its south polar plume, composed mostly of water vapor and ice grains, is one of the groundbreaking discoveries made by the Cassini spacecraft. During Cassini’s E2, E3, E5 and E7 encounters with Enceladus, the Ion and Neutral Mass Spectrometer (INMS) measured high neutral water vapor densities up to ~109 cm-3 (Waite et al., 2006; Teolis et al., 2010; Dong et al., 2011). We have constructed a physical model for the expected water vapor density in the plumes, based on supersonic radial outflow from one or more of the surface vents. We apply this model to possible surface sources of water vapor associated with the dust jets (Spitale and Porco, 2007; Hansen et al., 2008). Our model fits well with the E3, E5, and E7 INMS data. The fit is optimized by the 28 outflow velocity of ~ 550 – 750 m/s and the total source rate of ~ 1.5 − 3.5×10 H2O molecules/s (~ 450 – 1050 kg/s). The dust (ice grain) plumes of Enceladus have been observed by multiple Cassini instruments. We propose a composite ice grain size distribution covering a continuous size range from nanometer to micrometers, by combining the CAPS (Cassini Plasma Spectrometer), CDA (Cosmic Dust Analyzer), and RPWS (Radio and Plasma Wave Science) data (Hill et al., 2012; Kempf et al., 2008; Ye et al., 2012, 2013). We also study the grain charging process using the RPWS-LP (Langmuir Probe) data (Morooka et al., 2011). -
NASA's Lunar Atmosphere and Dust Environment Explorer (LADEE)
Geophysical Research Abstracts Vol. 13, EGU2011-5107-2, 2011 EGU General Assembly 2011 © Author(s) 2011 NASA’s Lunar Atmosphere and Dust Environment Explorer (LADEE) Richard Elphic (1), Gregory Delory (1,2), Anthony Colaprete (1), Mihaly Horanyi (3), Paul Mahaffy (4), Butler Hine (1), Steven McClard (5), Joan Salute (6), Edwin Grayzeck (6), and Don Boroson (7) (1) NASA Ames Research Center, Moffett Field, CA USA ([email protected]), (2) Space Sciences Laboratory, University of California, Berkeley, CA USA, (3) Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO USA, (4) NASA Goddard Space Flight Center, Greenbelt, MD USA, (5) LunarQuest Program Office, NASA Marshall Space Flight Center, Huntsville, AL USA, (6) Planetary Science Division, Science Mission Directorate, NASA, Washington, DC USA, (7) Lincoln Laboratory, Massachusetts Institute of Technology, Lexington MA USA Nearly 40 years have passed since the last Apollo missions investigated the mysteries of the lunar atmosphere and the question of levitated lunar dust. The most important questions remain: what is the composition, structure and variability of the tenuous lunar exosphere? What are its origins, transport mechanisms, and loss processes? Is lofted lunar dust the cause of the horizon glow observed by the Surveyor missions and Apollo astronauts? How does such levitated dust arise and move, what is its density, and what is its ultimate fate? The US National Academy of Sciences/National Research Council decadal surveys and the recent “Scientific Context for Exploration of the Moon” (SCEM) reports have identified studies of the pristine state of the lunar atmosphere and dust environment as among the leading priorities for future lunar science missions. -
Argonaut #2 2019 Cover.Indd 1 1/23/20 1:18 PM the Argonaut Journal of the San Francisco Historical Society Publisher and Editor-In-Chief Charles A
1/23/20 1:18 PM Winter 2020 Winter Volume 30 No. 2 Volume JOURNAL OF THE SAN FRANCISCO HISTORICAL SOCIETY VOL. 30 NO. 2 Argonaut #2_2019_cover.indd 1 THE ARGONAUT Journal of the San Francisco Historical Society PUBLISHER AND EDITOR-IN-CHIEF Charles A. Fracchia EDITOR Lana Costantini PHOTO AND COPY EDITOR Lorri Ungaretti GRapHIC DESIGNER Romney Lange PUBLIcatIONS COMMIttEE Hudson Bell Lee Bruno Lana Costantini Charles Fracchia John Freeman Chris O’Sullivan David Parry Ken Sproul Lorri Ungaretti BOARD OF DIREctORS John Briscoe, President Tom Owens, 1st Vice President Mike Fitzgerald, 2nd Vice President Kevin Pursglove, Secretary Jack Lapidos,Treasurer Rodger Birt Edith L. Piness, Ph.D. Mary Duffy Darlene Plumtree Nolte Noah Griffin Chris O’Sullivan Richard S. E. Johns David Parry Brent Johnson Christopher Patz Robyn Lipsky Ken Sproul Bruce M. Lubarsky Paul J. Su James Marchetti John Tregenza Talbot Moore Diana Whitehead Charles A. Fracchia, Founder & President Emeritus of SFHS EXECUTIVE DIREctOR Lana Costantini The Argonaut is published by the San Francisco Historical Society, P.O. Box 420470, San Francisco, CA 94142-0470. Changes of address should be sent to the above address. Or, for more information call us at 415.537.1105. TABLE OF CONTENTS A SECOND TUNNEL FOR THE SUNSET by Vincent Ring .....................................................................................................................................6 THE LAST BASTION OF SAN FRANCISCO’S CALIFORNIOS: The Mission Dolores Settlement, 1834–1848 by Hudson Bell .....................................................................................................................................22 A TENDERLOIN DISTRIct HISTORY The Pioneers of St. Ann’s Valley: 1847–1860 by Peter M. Field ..................................................................................................................................42 Cover photo: On October 21, 1928, the Sunset Tunnel opened for the first time. -
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. -
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. -
Guide to the Betty J. Meggers and Clifford Evans Papers
Guide to the Betty J. Meggers and Clifford Evans papers Tyler Stump and Adam Fielding Funding for the processing of this collection was provided by the Smithsonian Institution's Collections Care and Preservation Fund. December 2015 National Anthropological Archives Museum Support Center 4210 Silver Hill Road Suitland, Maryland 20746 [email protected] http://www.anthropology.si.edu/naa/ Table of Contents Collection Overview ........................................................................................................ 1 Administrative Information .............................................................................................. 1 Biographical / Historical.................................................................................................... 2 Scope and Contents........................................................................................................ 5 Arrangement..................................................................................................................... 5 Bibliography...................................................................................................................... 6 Names and Subjects ...................................................................................................... 6 Container Listing ............................................................................................................. 8 Series 1: Personal, 1893-2012................................................................................. 8 Series 2: Writings, 1944-2011............................................................................... -
A Possible Albian Impact Crater at Murshid, Southern Oman
GeoArabia, Vol. 7, No. 4, 2002 Gulf PetroLink, Bahrain A possible Albian impact crater at Murshid, southern Oman Bruce Levell1, Pascal Richard2 and Folco Hoogendijk2, Petroleum Development Oman ABSTRACT During interpretation of a 3-D seismic survey in southern Oman a solitary, 2.5-km-wide circular basin with a central peak and raised rim was identified in the subsurface 35 km west of the Marmul oil field. The feature is the only one of its kind in the area. The basinal structure is probably of Late Cretaceous (Albian) age and the regional geology strongly suggests that it is neither a volcanic crater nor related to salt-dome tectonics or salt dissolution. It possibly represents a crater formed by a terrestrial impact event and has been named the Murshid crater. This report does not constitute a detailed investigation of the possible impact crater but rather records the 3-D seismic observations and the drilling that has taken place near the structure so far. INTRODUCTION During interpretation of a newly acquired 3-D seismic survey for oil exploration in southern Oman, a solitary 2.5-km-diameter circular basinal feature was identified as a possible impact structure and was named the Murshid crater. It lies 35 km west of the Marmul oil field in the South Oman Salt Basin (Figure 1). The center of the structure is at latitude 18º10’59"N, longitude 54º55’08”E, and it is buried at a depth of approximately 380 m below mean sea level (680 m below the ground surface). The authors are petroleum geologists who felt that the Murshid basinal structure needed reporting to the wider scientific community. -
Exploration of the Moon
Exploration of the Moon The physical exploration of the Moon began when Luna 2, a space probe launched by the Soviet Union, made an impact on the surface of the Moon on September 14, 1959. Prior to that the only available means of exploration had been observation from Earth. The invention of the optical telescope brought about the first leap in the quality of lunar observations. Galileo Galilei is generally credited as the first person to use a telescope for astronomical purposes; having made his own telescope in 1609, the mountains and craters on the lunar surface were among his first observations using it. NASA's Apollo program was the first, and to date only, mission to successfully land humans on the Moon, which it did six times. The first landing took place in 1969, when astronauts placed scientific instruments and returnedlunar samples to Earth. Apollo 12 Lunar Module Intrepid prepares to descend towards the surface of the Moon. NASA photo. Contents Early history Space race Recent exploration Plans Past and future lunar missions See also References External links Early history The ancient Greek philosopher Anaxagoras (d. 428 BC) reasoned that the Sun and Moon were both giant spherical rocks, and that the latter reflected the light of the former. His non-religious view of the heavens was one cause for his imprisonment and eventual exile.[1] In his little book On the Face in the Moon's Orb, Plutarch suggested that the Moon had deep recesses in which the light of the Sun did not reach and that the spots are nothing but the shadows of rivers or deep chasms. -
Crater Gradation in Gusev Crater and Meridiani Planum, Mars J
JOURNAL OF GEOPHYSICAL RESEARCH, VOL. 111, E02S08, doi:10.1029/2005JE002465, 2006 Crater gradation in Gusev crater and Meridiani Planum, Mars J. A. Grant,1 R. E. Arvidson,2 L. S. Crumpler,3 M. P. Golombek,4 B. Hahn,5 A. F. C. Haldemann,4 R. Li,6 L. A. Soderblom,7 S. W. Squyres,8 S. P. Wright,9 and W. A. Watters10 Received 19 April 2005; revised 21 June 2005; accepted 27 June 2005; published 6 January 2006. [1] The Mars Exploration Rovers investigated numerous craters in Gusev crater and Meridiani Planum during the first 400 sols of their missions. Craters vary in size and preservation state but are mostly due to secondary impacts at Gusev and primary impacts at Meridiani. Craters at both locations are modified primarily by eolian erosion and infilling and lack evidence for modification by aqueous processes. Effects of gradation on crater form are dependent on size, local lithology, slopes, and availability of mobile sediments. At Gusev, impacts into basaltic rubble create shallow craters and ejecta composed of resistant rocks. Ejecta initially experience eolian stripping, which becomes weathering-limited as lags develop on ejecta surfaces and sediments are trapped within craters. Subsequent eolian gradation depends on the slow production of fines by weathering and impacts and is accompanied by minor mass wasting. At Meridiani the sulfate-rich bedrock is more susceptible to eolian erosion, and exposed crater rims, walls, and ejecta are eroded, while lower interiors and low-relief surfaces are increasingly infilled and buried by mostly basaltic sediments. Eolian processes outpace early mass wasting, often produce meters of erosion, and mantle some surfaces. -
Mars Reconnaissance Orbiter and Opportunity Observations Of
PUBLICATIONS Journal of Geophysical Research: Planets RESEARCH ARTICLE Mars Reconnaissance Orbiter and Opportunity 10.1002/2014JE004686 observations of the Burns formation: Crater Key Point: hopping at Meridiani Planum • Hydrated Mg and Ca sulfate Burns formation minerals mapped with MRO R. E. Arvidson1, J. F. Bell III2, J. G. Catalano1, B. C. Clark3, V. K. Fox1, R. Gellert4, J. P. Grotzinger5, and MER data E. A. Guinness1, K. E. Herkenhoff6, A. H. Knoll7, M. G. A. Lapotre5, S. M. McLennan8, D. W. Ming9, R. V. Morris9, S. L. Murchie10, K. E. Powell1, M. D. Smith11, S. W. Squyres12, M. J. Wolff3, and J. J. Wray13 1 2 Correspondence to: Department of Earth and Planetary Sciences, Washington University in Saint Louis, Missouri, USA, School of Earth and Space R. E. Arvidson, Exploration, Arizona State University, Tempe, Arizona, USA, 3Space Science Institute, Boulder, Colorado, USA, 4Department of [email protected] Physics, University of Guelph, Guelph, Ontario, Canada, 5Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, California, USA, 6U.S. Geological Survey, Astrogeology Science Center, Flagstaff, Arizona, USA, 7 8 Citation: Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, Massachusetts, USA, Department Arvidson, R. E., et al. (2015), Mars of Geosciences, Stony Brook University, Stony Brook, New York, USA, 9NASA Johnson Space Center, Houston, Texas, USA, Reconnaissance Orbiter and Opportunity 10Applied Physics Laboratory, Johns Hopkins University, Laurel, Maryland, USA, 11NASA Goddard Space Flight Center, observations of the Burns formation: Greenbelt, Maryland, USA, 12Department of Astronomy, Cornell University, Ithaca, New York, USA, 13School of Earth and Crater hopping at Meridiani Planum, J. -
Archons (Commanders) [NOTICE: They Are NOT Anlien Parasites], and Then, in a Mirror Image of the Great Emanations of the Pleroma, Hundreds of Lesser Angels
A R C H O N S HIDDEN RULERS THROUGH THE AGES A R C H O N S HIDDEN RULERS THROUGH THE AGES WATCH THIS IMPORTANT VIDEO UFOs, Aliens, and the Question of Contact MUST-SEE THE OCCULT REASON FOR PSYCHOPATHY Organic Portals: Aliens and Psychopaths KNOWLEDGE THROUGH GNOSIS Boris Mouravieff - GNOSIS IN THE BEGINNING ...1 The Gnostic core belief was a strong dualism: that the world of matter was deadening and inferior to a remote nonphysical home, to which an interior divine spark in most humans aspired to return after death. This led them to an absorption with the Jewish creation myths in Genesis, which they obsessively reinterpreted to formulate allegorical explanations of how humans ended up trapped in the world of matter. The basic Gnostic story, which varied in details from teacher to teacher, was this: In the beginning there was an unknowable, immaterial, and invisible God, sometimes called the Father of All and sometimes by other names. “He” was neither male nor female, and was composed of an implicitly finite amount of a living nonphysical substance. Surrounding this God was a great empty region called the Pleroma (the fullness). Beyond the Pleroma lay empty space. The God acted to fill the Pleroma through a series of emanations, a squeezing off of small portions of his/its nonphysical energetic divine material. In most accounts there are thirty emanations in fifteen complementary pairs, each getting slightly less of the divine material and therefore being slightly weaker. The emanations are called Aeons (eternities) and are mostly named personifications in Greek of abstract ideas. -
Crater Geometry and Ejecta Thickness of the Martian Impact Crater Tooting
Meteoritics & Planetary Science 42, Nr 9, 1615–1625 (2007) Abstract available online at http://meteoritics.org Crater geometry and ejecta thickness of the Martian impact crater Tooting Peter J. MOUGINIS-MARK and Harold GARBEIL Hawai‘i Institute of Geophysics and Planetology, University of Hawai‘i, Honolulu, Hawai‘i 96822, USA (Received 25 October 2006; revision accepted 04 March 2007) Abstract–We use Mars Orbiter Laser Altimeter (MOLA) topographic data and Thermal Emission Imaging System (THEMIS) visible (VIS) images to study the cavity and the ejecta blanket of a very fresh Martian impact crater ~29 km in diameter, with the provisional International Astronomical Union (IAU) name Tooting crater. This crater is very young, as demonstrated by the large depth/ diameter ratio (0.065), impact melt preserved on the walls and floor, an extensive secondary crater field, and only 13 superposed impact craters (all 54 to 234 meters in diameter) on the ~8120 km2 ejecta blanket. Because the pre-impact terrain was essentially flat, we can measure the volume of the crater cavity and ejecta deposits. Tooting crater has a rim height that has >500 m variation around the rim crest and a very large central peak (1052 m high and >9 km wide). Crater cavity volume (i.e., volume below the pre-impact terrain) is ~380 km3 and the volume of materials above the pre-impact terrain is ~425 km3. The ejecta thickness is often very thin (<20 m) throughout much of the ejecta blanket. There is a pronounced asymmetry in the ejecta blanket, suggestive of an oblique impact, which has resulted in up to ~100 m of additional ejecta thickness being deposited down-range compared to the up-range value at the same radial distance from the rim crest.