COSPAR - IAU - LSI COLLOQUIUM on LUNAR Dynmli CS and OBSERVATIONAL COORDINATE SYSTEMS
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Advances in the Interpretation and Analysis of Lunar Occultation Light Curves
A&A 538, A56 (2012) Astronomy DOI: 10.1051/0004-6361/201118476 & c ESO 2012 Astrophysics Advances in the interpretation and analysis of lunar occultation light curves A. Richichi1,2 and A. Glindemann2 1 National Astronomical Research Institute of Thailand, 191 Siriphanich Bldg., Huay Kaew Rd., Suthep, Muang, Chiang Mai 50200, Thailand e-mail: [email protected] 2 European Southern Observatory, Karl-Schwarzschild-Str. 2, 85748 Garching bei München, Germany Received 18 November 2011 / Accepted 23 December 2011 ABSTRACT Context. The introduction of fast 2D detectors and the use of very large telescopes have significantly advanced the sensitivity and accuracy of the lunar occultation technique. Recent routine observations at the ESO Very Large Telescope have yielded hundreds of events with results, especially in the area of binary stars, which are often beyond the capabilities of any other techniques. Aims. With the increase in the quality and in the number of the events, subtle features in the light curve patterns have occasionally been detected which challenge the standard analytical definition of the lunar occultation phenomenon as diffraction from an infinite straight edge. We investigate the possible causes for the observed peculiarities. Methods. We have evaluated the available statistics of distortions in occultation light curves observed at the ESO VLT, and compared it to data from other facilities. We have developed an alternative approach to model and interpret lunar occultation light curves, based on 2D diffraction integrals describing the light curves in the presence of an arbitrary lunar limb profile. We distinguish between large limb irregularities requiring the Fresnel diffraction formalism, and small irregularities described by Fraunhofer diffraction. -
University Microfilms, a XEROX Company, Ann Arbor, Michigan
.72-4480 FAJEMIROKUN, Francis Afolabi, 1941- APPLICATION OF NEW OBSERVATIONAL SYSTEMS FOR SELENODETIC CONTROL. The Ohio State University, Ph.D., 1971 Geodesy University Microfilms, A XEROX Company, Ann Arbor, Michigan THIS DISSERTATION HAS BEEN MICROFILMED EXACTLY AS RECEIVED APPLICATION OF NEW OBSERVATIONAL SYSTEMS FOR SELENODETIC CONTROL DISSERTATION Presented in Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy in the Graduate School of The Ohio State University by Francis Afolabi Fajemirokun, B. Sc., M. Sc. The Ohio State University 1971 Approved by l/m /• A dviser Department of Geodetic Science PLEASE NOTE: Some Pages have indistinct p rin t. Filmed as received. UNIVERSITY MICROFILMS To Ijigbola, Ibeolayemi and Oladunni ACKNOW LEDGEME NTS The author wishes to express his deep gratitude to the many persons, without whom this work would not have been possible. First and foremost, the author is grateful to the Department of Geodetic Science and themembers of its staff, for the financial support and academic guidance given to him during his studies here. In particular, the author wishes to thank his adviser Professor Ivan I. Mueller, for his encouragement, patience and guidance through the various stages of this work. Professors Urho A. Uotila, Richard H. Rapp and Gerald H. Newsom served on the author’s reading committee, and offered many valuable suggestions to help clarify many points. The author has also enjoyed working with other graduate students in the department, especially with the group at 231 Lord Hall, where there was always an atmosphere of enthusiastic learning and of true friendship. The author is grateful to the various scientists outside the department, with whom he had discussions on the subject of this work, especially to the VLBI group at the Smithsonian Astrophysical Observatory in Cambridge, Ma s sachu s s etts . -
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. -
Applications of Solar Wind Particle Impact Simulations at Lunar Magnetic Anomalies to the Study of Lunar Swirls
47th Lunar and Planetary Science Conference (2016) 2648.pdf APPLICATIONS OF SOLAR WIND PARTICLE IMPACT SIMULATIONS AT LUNAR MAGNETIC ANOMALIES TO THE STUDY OF LUNAR SWIRLS. C. J. Tai Udovicic1, G. Y. Kramer2, and E. M. Harnett3, 1Dept of Earth Sciences, University of Toronto, 22 Russell St, Toronto, ON, Canada, ([email protected]), 2Lunar and Planetary Institute, 3600 Bay Area Bvld, Houston, TX, ([email protected]), 3University of Washington, Earth and Space Sciences, Seattle, WA ([email protected]). Introduction: Lunar swirls are high albedo features highlands often appear to have swirl-like anomalies due that exhibit low spectral maturity. They have been to their complicated topography. To mitigate this, we identified at various sites on the Moon, and all coincide generated a slope map from the WAC GLD100 (SLP), with a lunar magnetic anomaly (magnomaly) [1], which we overlayed with the WAC 643 nm normalized although not all magnomalies have an identifiable swirl. reflectance image to distinguish high albedo swirls from The leading hypothesis for lunar swirl origin is high albedo slopes. Even so, after one pass of the region, presented in [2] as magnetic field standoff of the solar only about half of the swirls could be detected with this wind which causes uneven space weathering at the swirl method alone. The remaining half were found after surface. This hypothesis fails to explain why lunar using particle simulations as a guide. swirls are observed at some but not all of the magnetic Solar wind particle tracking simulations: We anomalies present on the Moon. To investigate the solar used the 2D solar wind particle tracking simulation wind standoff hypothesis further and to improve swirl presented in [2]. -
Apollo 17 Index: 70 Mm, 35 Mm, and 16 Mm Photographs
General Disclaimer One or more of the Following Statements may affect this Document This document has been reproduced from the best copy furnished by the organizational source. It is being released in the interest of making available as much information as possible. This document may contain data, which exceeds the sheet parameters. It was furnished in this condition by the organizational source and is the best copy available. This document may contain tone-on-tone or color graphs, charts and/or pictures, which have been reproduced in black and white. This document is paginated as submitted by the original source. Portions of this document are not fully legible due to the historical nature of some of the material. However, it is the best reproduction available from the original submission. Produced by the NASA Center for Aerospace Information (CASI) Preparation, Scanning, Editing, and Conversion to Adobe Portable Document Format (PDF) by: Ronald A. Wells University of California Berkeley, CA 94720 May 2000 A P O L L O 1 7 I N D E X 7 0 m m, 3 5 m m, A N D 1 6 m m P H O T O G R A P H S M a p p i n g S c i e n c e s B r a n c h N a t i o n a l A e r o n a u t i c s a n d S p a c e A d m i n i s t r a t i o n J o h n s o n S p a c e C e n t e r H o u s t o n, T e x a s APPROVED: Michael C . -
Arxiv:2107.09416V1
Draft version July 21, 2021 A Typeset using L TEX twocolumn style in AASTeX631 Estimation of the Eclipse Solar Radius by Flash Spectrum Video Analysis Luca Quaglia,1 John Irwin,2 Konstantinos Emmanouilidis,3 and Alessandro Pessi4 1Sydney, New South Wales, Australia 2Guildford, England, United Kingdom 3Thessaloniki, Greece 4Milan, Italy ABSTRACT The value of the eclipse solar radius during the 2017 August 21st total solar eclipse was estimated to be S⊙ = (959.95±0.05)”at 1 au with no significant dependence on wavelength. The measurement was obtained from the analysis of a video of the eclipse flash spectrum recorded at the southern limit of the umbral shadow path. Our analysis was conducted by extracting light curves from the flash spectrum and comparing them to simulated light curves. Simulations were performed by integrating the limb darkening function (LDF) over the exposed area of photosphere. These numerical integrations relied upon very precise computations of the relative movement of the lunar and solar limbs. Keywords: Solar radius (1488) — Solar eclipses (1489) — Flash spectrum (541) — Light curves (918) — Astronomical simulations (1857) 1. INTRODUCTION rameters is now below the milliarcsecond level while the accuracy of UT1 determination is well below the mil- The value of the solar radius at unit distance S⊙ is one of the fundamental quantities needed to perform very lisecond level. Satellite missions in the last decade have precise eclipse computations. Some of the other required vastly improved the knowledge of the topography of the inputs are: accurate ephemerides for the position of the Moon (Smith et al. 2017) to better than 10 m (corre- centres of mass of the Sun and Moon; accurate models sponding to about 5 mas at the mean geocentric dis- for the orientation of the Earth and Moon; and detailed tance of the Moon), allowing accurate computations of data on the topography of the Moon and Earth. -
Strategy for Optimal, Long-Term Stationkeeping of Libration Point Orbits in the Earth-Moon System
Strategy for Optimal, Long-Term Stationkeeping of Libration Point Orbits in the Earth-Moon System Thomas A. Pavlak∗ and Kathleen C. Howelly Purdue University, West Lafayette, IN, 47907-2045, USA In an effort to design low-cost maneuvers that reliably maintain unstable libration point orbits in the Earth-Moon system for long durations, an existing long-term stationkeeping strategy is augmented to compute locally optimal maneuvers that satisfy end-of-mission constraints downstream. This approach reduces stationkeeping costs for planar and three- dimensional orbits in dynamical systems of varying degrees of fidelity and demonstrates the correlation between optimal maneuver direction and the stable mode observed during ARTEMIS mission operations. An optimally-constrained multiple shooting strategy is also introduced that is capable of computing near optimal maintenance maneuvers without formal optimization software. I. Introduction Most orbits in the vicinity of collinear libration points are inherently unstable and, consequently, sta- tionkeeping strategies are a critical component of mission design and operations in these chaotic dynamical regions. Stationkeeping is particularly important for libration point missions in the Earth-Moon system since fast time scales require that orbit maintenance maneuvers be implemented approximately once per week. Assuming that acceptable orbit determination solutions require 3-4 days to obtain, stationkeeping ∆V planning activities must be quick, efficient, and effective. Furthermore, the duration of a libration point mission is often dictated by the remaining propellant so a key capability is maintenance maneuvers that are low-cost. Thus, to accommodate a likely increase in future operations in the vicinity of the Earth-Moon libration points, fast, reliable algorithms capable of rapidly computing low-cost stationkeeping maneuvers, with little or no human interaction, are critical. -
INTERAGENCY REPORT: ASTROGEOLOGY 7 ADVANCED SYSTEMS TRAVERSE RESEARCH PROJECT REPORT by G
INTERAGENCY REPORT: ASTROGEOLOGY 7 ADVANCED SYSTEMS TRAVERSE RESEARCH PROJECT REPORT By G. E. Ulrich With a Section on Problems for Geologic Investigations of the Orientale Region of the Moon By R. S. Saunders July 1968 CONTENTS Page Abs tract . ............. 1 Introduct ion . •• # • ••• ••• .' • 2 Physiographic subdivision of the lunar surface 3 Site selection and preliminary traverse research. 8 Lunar topographic data •••••••.•.•••••• 17 Objectives and evaluation of traverse concepts • 20 Recommendations for continued traverse research .••• 26 Problems for geologic investigations of the Orientale region of the Moon, by R. S. Saunders 30 Introduct ion •.•• •••. 30 Physiography 30 Pre-Orbiter observations and i~terpretations 35 Geologic interpretations based on Orbiter photography ••••••••• 38 Conelusions •••• .•••. 54 References 56 ILLUSTRATIONS Figure 1. Map and index to photographs of Orientale basin region ••••.•••••• 4 2. Crater-size frequency distributions of Orientale basin terrain units •••••• 11 3. Orientale basin region showing pre- liminary traverse evaluation areas ••••• 14 4. Effect of photographic exposure on shadow measurements 15 5. Alternate traverse areas for short and intermediate duration missions. North eastern sector of central Orientale basin ................... 24 6. Preliminary photogeologic map of the Orientale basin region. .•• .. .. 32 iii Page Figure 7. Sketch map of Mare Orientale region prepared from Earth-based telescopic photography • 36 8-21. Orbiter IV photographs of Orientale basin region showing-- . 8. Part of wr{nk1e ridge . 41 9. Slump scarps around steptoe and collapse depression . 44 10. Slump scarps along margin of central mare basin outlining collapse depression • • . • 44 11. Possible caldera 45 12. Northeast quadrant of inner ring showing central basin material and mare units 45 13. -
Simulations of Particle Impact at Lunar Magnetic Anomalies and Comparison with Spectral Observations
Simulations of Particle Impact at Lunar Magnetic Anomalies and Comparison with Spectral Observations Erika Harnett∗ Department of Earth and Space Science, University of Washington,Seattle, WA 98195-1310, USA Georgiana Kramer Lunar and Planetary Institute, 3600 Bay Area Blvd, Houston, TX 77058, USA Christian Udovicic Department of Physics, University of Toronto, 60 St George St,Toronto, ON M5S 1A7, Canada Ruth Bamford RAL Space, STFC, Rutherford Appleton Laboratory,Chilton, Didcot Ox11 0Qx, UK (Dated: November 5, 2018) Ever since the Apollo era, a question has remained as to the origin of the lunar swirls (high albedo regions coincident with the regions of surface magnetization). Different processes have been proposed for their origin. In this work we test the idea that the lunar swirls have a higher albedo relative to surrounding regions because they deflect incoming solar wind particles that would otherwise darken the surface. 3D particle tracking is used to estimate the influence of five lunar magnetic anomalies on incoming solar wind. The regions investigated include Mare Ingenii, Gerasimovich, Renier Gamma, Northwest of Apollo and Marginis. Both protons and electrons are tracked as they interact with the anomalous magnetic field and impact maps are calculated. The impact maps are then compared to optical observations and comparisons are made between the maxima and minima in surface fluxes and the albedo and optical maturity of the regions. Results show deflection of slow to typical solar wind particles on a larger scale than the fine scale optical, swirl, features. It is found that efficiency of a particular anomaly for deflection of incoming particles does not only scale directly with surface magnetic field strength, but also is a function of the coherence of the magnetic field. -
Mars Astrobiological Cave and Internal Habitability Explorer (MACIE): a New Frontiers Mission Concept
Mars Astrobiological Cave and Internal habitability Explorer (MACIE): A New Frontiers Mission Concept By: C. Phillips-Lander ([email protected])1, A. Agha-mohamamdi2, J. J. Wynne3, T. N. Titus4, N. Chanover5, C. Demirel-Floyd6, K. Uckert2, K. Williams4, D. Wyrick1, J.G. Blank7,8, P. Boston8, K. Mitchell2, A. Kereszturi9, J. Martin-Torres10,11, S. Shkolyar12, N. Bardabelias13, S. Datta14, K. Retherford1, Lydia Sam11, A. Bhardwaj11, A. Fairén15,16, D. Flannery17, R. Wiens17 1Southwest Research Institute 2 NASA Jet Propulsion Laboratory 3Northern Arizona University 4U.S. Geological Survey 5New Mexico State University 6University of Oklahoma 7Blue Marble Space Institute of Science 8NASA Ames Research Center 9Konkoly Thege Miklos Astronomical Institute, Budapest, Hungary 10Instituto Andaluz de Ciencias de la Tierra (CSIC-UGR), Spain 11University of Aberdeen, United Kingdo 12USRA/NASA Goddard 13University of Arizona 14University of Texas-San Antonio 15Centro de Astrobiogía, Spain 16Cornell University 17Queensland University for Technology, Australia 18Los Alamos National Laboratory Cosigners 1 Summary of Key Points 1. Martian subsurface habitability and astrobiology can be evaluated via a lava tube cave, without drilling. 2. MACIE addresses two key goals of the Decadal Survey (2013-2022) and three MEPAG goals. 3. New advances in robotic architectures, autonomous navigation, target sample selection, and analysis will enable MACIE to explore the Martian subsurface. 1. Martian lava tubes are one of the best places to search for evidence of life The Mars Astrobiological Cave and Internal habitability Explorer (MACIE) mission concept is named for Macie Roberts, one of NASA’s ‘human computers’ (Conway 2007). MACIE would access the Martian subsurface via a lava tube. -
Trajectory Design Tools for Libration and Cislunar Environments
TRAJECTORY DESIGN TOOLS FOR LIBRATION AND CISLUNAR ENVIRONMENTS David C. Folta, Cassandra M. Webster, Natasha Bosanac, Andrew D. Cox, Davide Guzzetti, and Kathleen C. Howell National Aeronautics and Space Administration Goddard Space Flight Center, Greenbelt, MD, 20771 [email protected], [email protected] School of Aeronautics and Astronautics, Purdue University, West Lafayette, IN 47907 {nbosanac,cox50,dguzzett,howell}@purdue.edu ABSTRACT supplies insight into the natural dynamics associated with multi- body systems. In fact, such information enables a rapid and robust Innovative trajectory design tools are required to support methodology for libration point orbit and transfer design when challenging multi-body regimes with complex dynamics, uncertain used in combination with numerical techniques such as targeting perturbations, and the integration of propulsion influences. Two and optimization. distinctive tools, Adaptive Trajectory Design and the General Strategies that offer interactive access to a variety of solutions Mission Analysis Tool have been developed and certified to enable a thorough and guided exploration of the trajectory design provide the astrodynamics community with the ability to design space. ATD is intended to provide access to well-known solutions multi-body trajectories. In this paper we discuss the multi-body that exist within the framework of the Circular Restricted Three- design process and the capabilities of both tools. Demonstrable Body Problem (CR3BP) by leveraging both interactive and applications to confirmed missions, the Lunar IceCube CubeSat automated features to facilitate trajectory design in multi-body mission and the Wide-Field Infrared Survey Telescope Sun-Earth regimes [8]. In particular, well-known solutions from the CR3BP, such as body-centered, resonant and libration point periodic and L2 mission, are presented.