Direct Evidence of Surface Exposed Water Ice in the Lunar Polar Regions
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EPSC2012-280 2012 European Planetary Science Congress 2012 Eeuropeapn Planetarsy Science Ccongress C Author(S) 2012
EPSC Abstracts Vol. 7 EPSC2012-280 2012 European Planetary Science Congress 2012 EEuropeaPn PlanetarSy Science CCongress c Author(s) 2012 A Simulation of exosphere of Ceres Ruby Lin Tu (1), Wing-Huen Ip(1,2,3) and Yung-Ching Wang (3) (1) Institute of Space Science, National Central University, Taiwan, (2) Institute of Astronomy, National Central University, Taiwan, (3) Space Science Institute, Macau University Science and Technology, Macau Abstract For the purpose of tracing the ballistic trajectories of water molecules on Ceres’ surface, we have to After Vesta, the NASA Dawn spacecraft will visit the produce a surface temperature map by omitting the largest asteroid Ceres, to carry out in-depth topographic variations and the presence of impact observations of its surface morphology and craters. Our model solves the heat conduction mineralogical composition. We examine different equation by taking account of the energy balance source mechanisms of a possible surface-bounded condition at the surface boundary and the lower exosphere composed of water molecules and other boundary condition (with dT/dz=0) into account. In species. Our preliminary assessment is that solar between the heat diffusion equation is solved by wind interaction and meteoroid impact are not using the Crank-Nicolson finite difference routine adequate because of the large injection speed of the gas at production relative to the surface escape velocity of Ceres. One potential source is a low-level (1) outgassing effect from its subsurface due to thermal sublimation. In this work, the scenario of building up a tenuous exosphere by ballistic transport and the eventual recycling of the water molecules to the polar cold trap is described. -
Project Selene: AIAA Lunar Base Camp
Project Selene: AIAA Lunar Base Camp AIAA Space Mission System 2019-2020 Virginia Tech Aerospace Engineering Faculty Advisor : Dr. Kevin Shinpaugh Team Members : Olivia Arthur, Bobby Aselford, Michel Becker, Patrick Crandall, Heidi Engebreth, Maedini Jayaprakash, Logan Lark, Nico Ortiz, Matthew Pieczynski, Brendan Ventura Member AIAA Number Member AIAA Number And Signature And Signature Faculty Advisor 25807 Dr. Kevin Shinpaugh Brendan Ventura 1109196 Matthew Pieczynski 936900 Team Lead/Operations Logan Lark 902106 Heidi Engebreth 1109232 Structures & Environment Patrick Crandall 1109193 Olivia Arthur 999589 Power & Thermal Maedini Jayaprakash 1085663 Robert Aselford 1109195 CCDH/Operations Michel Becker 1109194 Nico Ortiz 1109533 Attitude, Trajectory, Orbits and Launch Vehicles Contents 1 Symbols and Acronyms 8 2 Executive Summary 9 3 Preface and Introduction 13 3.1 Project Management . 13 3.2 Problem Definition . 14 3.2.1 Background and Motivation . 14 3.2.2 RFP and Description . 14 3.2.3 Project Scope . 15 3.2.4 Disciplines . 15 3.2.5 Societal Sectors . 15 3.2.6 Assumptions . 16 3.2.7 Relevant Capital and Resources . 16 4 Value System Design 17 4.1 Introduction . 17 4.2 Analytical Hierarchical Process . 17 4.2.1 Longevity . 18 4.2.2 Expandability . 19 4.2.3 Scientific Return . 19 4.2.4 Risk . 20 4.2.5 Cost . 21 5 Initial Concept of Operations 21 5.1 Orbital Analysis . 22 5.2 Launch Vehicles . 22 6 Habitat Location 25 6.1 Introduction . 25 6.2 Region Selection . 25 6.3 Locations of Interest . 26 6.4 Eliminated Locations . 26 6.5 Remaining Locations . 27 6.6 Chosen Location . -
(Unin)Habitable? Runaway Greenhouse
GEOS 22060/ GEOS 32060 / ASTR 45900 What makes a planet (unin)habitable? Runaway greenhouse Lecture 8 Tuesday 30 April 2019 Logiscs • Homework 1 and Homework 2 are graded • Homework 3 will be issued on Wed or Thu and due on Fri 10 • Total number of homeworks will be 6 (hopefully 7) • Midterm feedback form results: Course outline Founda6ons (1-2 weeks) • Earth history • HZ concept, atmospheric science essenEals • Post-Hadean Earth system Principles – how are habitable planets ini6ated and sustained? (4-5 weeks) • Volale supply, volale escape TODAY • Runaway greenhouse, moist greenhouse • Long-term climate evoluEon • Specifics (2.5 weeks) • Hyperthermals on Earth Earth science • Early Mars • Oceans within ice-covered moons • Exoplanetary systems e.g. TRAPPIST-1 system planetary science Lecture 7 wrap-up • Energy-limit: XUV driven escape more-likely- than-not sculpts the exoplanet radius-period distribuEon (‘photo-evaporaon valley’) • Diffusion limit: what regulates H loss from Venus, Earth and Mars today • Impact erosion – giant impacts and planetesimal impacts Wrap-up: impact erosion Nuclear tests Hydrocode Terrestrial impact craters Two-stage gas gun Formaon of Earth-sized planets involves giant (oligarchic) impacts. Masses of resulEng planets (Earths) * = giant impacts The output underlying this plot was generated by C. Cossou. The Moon-forming Simula8on intended to impact was not reproduce “typical” the last big impact Kepler system of short-period, on Earth, but it was 8ghtly-packed inner planets the last Eme that Earth hit another planet. The atmosphere-loss escape efficiency of giant impacts is set by the ground-moEon speed Schlichng & Mukhopadhay 2018 Ocean removal by giant impacts? (Ocean vaporizaon != ocean removal) Simulaons suggest that the Moon- forming impact was marginally able to remove any pre-exisEng Earth ocean 2 Qs ~ ve for oligarchic impact Stewart et al. -
Water Loss from Terrestrial Planets with CO2-Rich Atmospheres
Water loss from terrestrial planets with CO2-rich atmospheres R. D. Wordsworth Department of the Geophysical Sciences, University of Chicago, 60637 IL, USA [email protected] and R. T. Pierrehumbert Department of the Geophysical Sciences, University of Chicago, 60637 IL, USA ABSTRACT Water photolysis and hydrogen loss from the upper atmospheres of terrestrial planets is of fundamental importance to climate evolution but remains poorly understood in general. Here we present a range of calculations we performed to study the dependence of water loss rates from terrestrial planets on a range of atmospheric and external parameters. We show that CO2 can only cause sig- nificant water loss by increasing surface temperatures over a narrow range of conditions, with cooling of the middle and upper atmosphere acting as a bottle- neck on escape in other circumstances. Around G-stars, efficient loss only occurs on planets with intermediate CO2 atmospheric partial pressures (0.1 to 1 bar) that receive a net flux close to the critical runaway greenhouse limit. Because G-star total luminosity increases with time but XUV/UV luminosity decreases, this places strong limits on water loss for planets like Earth. In contrast, for a CO2-rich early Venus, diffusion limits on water loss are only important if clouds caused strong cooling, implying that scenarios where the planet never had surface liquid water are indeed plausible. Around M-stars, water loss is primarily a func- arXiv:1306.3266v2 [astro-ph.EP] 12 Oct 2013 tion of orbital distance, with planets that absorb less flux than ∼ 270 W m−2 (global mean) unlikely to lose more than one Earth ocean of H2O over their lifetimes unless they lose all their atmospheric N2/CO2 early on. -
Icebreaker: a Lunar South Pole Exploring Robot Cmu-Ri-Tr-97-22
ICEBREAKER: A LUNAR SOUTH POLE EXPLORING ROBOT CMU-RI-TR-97-22 Matthew C. Deans Alex D. Foessel Gregory A. Fries Diana LaBelle N. Keith Lay Stewart Moorehead Ben Shamah Kimberly J. Shillcutt Professor: Dr. William Whittaker The Robotics Institute Carnegie Mellon University Pittsburgh PA 15213 Spring 1996-97 Executive Summary Icebreaker: A Lunar South Pole Exploring Robot Due to the low angles of sunlight at the lunar poles, craters and other depressions in the polar regions can contain areas which are in permanent darkness and are at cryogenic temperatures. Many scientists have theorized that these cold traps could contain large quantities of frozen volatiles such as water and carbon dioxide which have been deposited over billions of years by comets, meteors and solar wind. Recent bistatic radar data from the Clementine mission has yielded results consistent with water ice at the South Pole of the Moon however Earth based observations from the Arecibo Radar Observatory indicate that ice may not exist. Due to the controversy surrounding orbital and Earth based observations, the only way to definitively answer the question of whether ice exists on the Lunar South Pole is in situ analysis. The discovery of water ice and other volatiles on the Moon has many important benefits. First, this would provide a source of rocket fuel which could be used to power rockets to Earth, Mars or beyond, avoiding the high cost of Earth based launches. Secondly, water and carbon dioxide along with nitrogen from ammonia form the essential elements for life and could be used to help support human colonies on the Moon. -
Atmospheric Pressure As a Natural Climate Regulator for a Terrestrial Planet with a Biosphere
Atmospheric pressure as a natural climate regulator for a terrestrial planet with a biosphere King-Fai Li1, Kaveh Pahlevan, Joseph L. Kirschvink, and Yuk L. Yung Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA 91125 Edited by Norman H. Sleep, Stanford University, Stanford, CA, and approved April 10, 2009 (received for review September 24, 2008) Lovelock and Whitfield suggested in 1982 that, as the luminosity of models that include biological and geodynamic processes have the Sun increases over its life cycle, biologically enhanced silicate also been developed (10, 11), but estimates for the life span of weathering is able to reduce the concentration of atmospheric the biosphere remain at Ϸ1 Ga. carbon dioxide (CO2) so that the Earth’s surface temperature is All of these previous studies focused on the greenhouse effect maintained within an inhabitable range. As this process continues, due to direct absorption by atmospheric species such as water Ϫ2 however, between 100 and 900 million years (Ma) from now the vapor and CO2, whose radiative forcings are Ϸ80 Wm and Ϸ30 Ϫ2 CO2 concentration will reach levels too low for C3 and C4 photo- Wm , respectively. However, atmospheric pressure also plays a synthesis, signaling the end of the solar-powered biosphere. Here, critical role in the greenhouse effect through broadening of the we show that atmospheric pressure is another factor that adjusts infrared absorption lines of these gases by collisional interaction the global temperature by broadening infrared absorption lines of with other molecules (mainly N2 and O2 in the present atmo- greenhouse gases. -
Lpi Summer Intern Program in Planetary Science
LPI SUMMER INTERN PROGRAM IN PLANETARY SCIENCE Papers Presented at the August 11, 2011 — Houston, Texas Papers Presented at the Twenty-Seventh Annual Summer Intern Conference August 11, 2011 Houston, Texas 2011 Summer Intern Program for Undergraduates Lunar and Planetary Institute Sponsored by Lunar and Planetary Institute NASA Johnson Space Center Compiled in 2011 by Meeting and Publication Services Lunar and Planetary Institute USRA Houston 3600 Bay Area Boulevard, Houston TX 77058-1113 The Lunar and Planetary Institute is operated by the Universities Space Research Association under a cooperative agreement with the Science Mission Directorate of the National Aeronautics and Space Administration. Any opinions, findings, and conclusions or recommendations expressed in this volume are those of the author(s) and do not necessarily reflect the views of the National Aeronautics and Space Administration. Material in this volume may be copied without restraint for library, abstract service, education, or personal 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. 2011 Intern Conference iii HIGHLIGHTS Special Activities June 6, 2011 Tour of the Stardust Lab and Lunar Curatorial Facility JSC July 22, 2011 Tour of the Meteorite Lab JSC August 4, 2011 NASA VIP Tour JSC/ NASA Johnson Space Center and Sonny Carter SCTF Training Facility Site Visit Intern Brown Bag Seminars Date Speaker Topic Location June 8, 2011 Paul -
Sowers NIAC Final Report
Thermal Mining of Ices on Cold Solar System Bodies NIAC Phase I Final Report February 2019 George Sowers 1 Purpose This is the final report of the NASA Innovative Advanced Concepts (NIAC) Phase I study: Thermal Mining of Ices on Cold Solar System Bodies. It is submitted as partial fulfillment of the obligations of the Colorado School of Mines (CSM) under grant number 80NSSC19K0964. 2 Table of Contents List of Figures 5 List of Tables 9 1.0 Executive Summary 10 2.0 Introduction 15 3.0 Solar System Survey of Thermal Mining Targets 18 3.1 Potential Thermal Mining Targets 19 3.2 Thermal Mining Beyond the Moon 32 4.0 Thermal Mining Mission Context: Lunar Polar Ice Mining 34 4.1 Lunar Polar Ice Distribution Analysis 36 4.2 System Architecture 39 4.3 Functional Analysis 42 4.4 Ice Extraction Subsystem 46 4.5 Power Subsystem 53 4.6 Deployment and Setup 55 4.7 Operations 59 4.8 Mass and Cost Estimates 66 4.8.1 Subsystem Mass Estimates 66 4.8.2 Total Mass 70 4.8.3 Subsystem Cost Estimates 71 4.8.4 Total Cost 74 4.9 Business Case Analysis 76 4.9.1 The Propellant Market 76 4.9.2 Business Case Scenarios 80 4.9.3 Business Case Results 83 4.9.4 Comparison to Previous Analysis 87 5.0 Proof of Concept Testing 91 5.1 Testing Objectives and Approach 91 5.2 Icy Regolith Simulants 91 5.3 Block 1 Testing 95 5.3.1 Block 1 Apparatus 95 5.3.2 Block 1 Methodology 96 5.3.3 Block 1 Results 97 5.4 Block 2 Testing 105 5.4.1 Block 2 Apparatus 105 5.4.2 Block 2 Methodology 105 5.4.3 Block 2 Results 105 5.5 Test Conclusions 106 6.0 Summary and Conclusions 115 6.1 Bulletized Summary 115 6.2 Conclusions 116 6.3 Recommendations for Future Work 118 7.0 References 121 8.0 Appendix A: Solar System Catalogue 129 9.0 Appendix B: Acronym List 132 3 Acknowledgements This report was prepared by George Sowers, Ross Centers, David Dickson, Adam Hugo, Curtis Purrington, and Elizabeth Scott. -
Diving Into Exoplanets: Are Water Seas the Most Common?
ASTROBIOLOGY Volume 19, Number 5, 2019 Research Article ª Mary Ann Liebert, Inc. DOI: 10.1089/ast.2017.1720 Diving into Exoplanets: Are Water Seas the Most Common? F.J. Ballesteros,1 A. Fernandez-Soto,2,3 and V.J. Martı´nez1,3,4 Abstract One of the basic tenets of exobiology is the need for a liquid substratum in which life can arise, evolve, and develop. The most common version of this idea involves the necessity of water to act as such a substratum, both because that is the case on Earth and because it seems to be the most viable liquid for chemical reactions that lead to life. Other liquid media that could harbor life, however, have occasionally been put forth. In this work, we investigate the relative probability of finding superficial seas on rocky worlds that could be composed of nine different, potentially abundant, liquids, including water. We study the phase space size of habitable zones defined for those substances. The regions where there can be liquid around every type of star are calculated by using a simple model, excluding areas within a tidal locking distance. We combine the size of these regions with the stellar abundances in the Milky Way disk and modulate our result with the expected radial abundance of planets via a generalized Titius-Bode law, as statistics of exoplanet orbits seem to point to its adequateness. We conclude that seas of ethane may be up to nine times more frequent among exoplanets than seas of water, and that solvents other than water may play a significant role in the search for extrasolar seas. -
Lunar Pole Illumination and Communications Maps Computed from Goldstone Solar System Radar Elevation Data
IPN Progress Report 42-176 • February 15, 2009 Lunar Pole Illumination and Communications Maps Computed from Goldstone Solar System Radar Elevation Data Scott Bryant* The Goldstone Solar System Radar (GSSR) group at JPL produced a digital elevation model (DEM) of the lunar south pole using data obtained in 2006. This new DEM has 40-m hori- zontal resolution and about 5-m relative vertical accuracy. This article explains how this DEM was used to evaluate average solar illumination and Earth visibility near the lunar south pole. The elevation data were converted into local terrain horizon masks for the area within 100 km of the lunar south pole. These topocentric horizon masks were converted into selenographic latitude and longitude coordinates, then compared to regions bound- ing the maximum Sun and Earth motions relative to the Moon. Estimates of Earth visibility were computed by integrating the area of the region bounding the Earth’s motion that was below the horizon mask. Solar illumination and other metrics were computed similarly. Proposed lunar south pole base sites are examined in detail, with the best site showing multiyear averages of solar power availability of 92 percent and direct-to-Earth (DTE) com- munication availability of 51 percent. Results are compared with a theoretical model and with actual Sun and Earth visibility averaged over the years 2009 to 2028. Peaks near the lunar south pole with continuous DTE communications are also presented. Results for the lunar north pole were computed using the GSSR DEM of the lunar north pole produced in 1997. The article also explores using a heliostat to reduce the photovoltaic power system mass and complexity. -
The Behavior of Volatiles on the Lunar Surface
JOURNALOF GEOPHYSICALRESEARCH VOLUME 66. No. 9 SE•rX•a•E• 1961 The Behavior of Volatiles on the Lunar Surface KENNETHWATSON, BRUCE C. •{URRAY,AND I-IARRISON BROWN Division of GeologicalSciences, California Institute of Technology Pasadena, California Abstract. Volatiles, and water in particular, have been thought to be unstable on the lunar sur- face becauseof the rapid removal of constituentsof the lunar atmosphereby solar radiation, solar wind, and gravitational escape.The limiting factor in removal of a volatile from the moon,however, is actually the evaporationrate of the solidphase, which will be collectedat the coldestpoints on the lunar surface.We present a detailed theory of the behavior of volatiles on the lunar surface basedon solid-vaporkinetic relationships,and show that water is far more stable there than the noblegases or other possibleconstituents of the lunar atmosphere.Numerical calculationsindicate the amount of water lost from the moon sincethe present surfaceconditions were initiated is only a few gramsper squarecentimeter of the lunar surface.The amount of ice eventually detectedin lunar 'cold traps' thus will provide a sensitiveindication of the degreeof chemicaldifferentiation of the moon. 1. INTRODUCTION on the lunar surfaceover the above time period. Previousanalyses of the behavior of volatiles Conversely, the absence of lunar ice would on the lunar surface [Spitzer, 1952; Kuiper, 1952; indicate an extremelysmall amount of chemical differentiation of the lunar mass. Urey, 1952; Opik and Singer, 1960; Vestine, 1958] have all indicated that volatiles could not We will first developthe theory of the behavior of volatiles on the lunar surface, and then survive there for extended periods of time, and that water is particularly unstablebecause of its investigate the best numerical values of the low molecular weight and ease of ionization. -
Illumination Conditions of the Lunar Polar Regions Using LOLA Topography ⇑ E
Icarus 211 (2011) 1066–1081 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Illumination conditions of the lunar polar regions using LOLA topography ⇑ E. Mazarico a,b, ,1, G.A. Neumann a, D.E. Smith a,b, M.T. Zuber b, M.H. Torrence a,c a NASA Goddard Space Flight Center, Planetary Geodynamics Laboratory, Greenbelt, MD 20771, United States b Massachusetts Institute of Technology, Department of Earth, Atmospheric and Planetary Sciences, Cambridge, MA 02139, United States c Stinger Ghaffarian Technologies, Inc., Greenbelt, MD 20770, United States article info abstract Article history: We use high-resolution altimetry data obtained by the Lunar Orbiter Laser Altimeter instrument onboard Received 21 May 2010 the Lunar Reconnaissance Orbiter to characterize present illumination conditions in the polar regions of Revised 24 October 2010 the Moon. Compared to previous studies, both the spatial and temporal extent of the simulations are Accepted 29 October 2010 increased significantly, as well as the coverage (fill ratio) of the topographic maps used, thanks to the Available online 12 November 2010 28 Hz firing rate of the five-beam instrument. We determine the horizon elevation in a number of direc- tions based on 240 m-resolution polar digital elevation models reaching down to 75° latitude. The illu- Keyword: mination of both polar regions extending to 80° can be calculated for any geometry from those horizon Moon longitudinal profiles. We validated our modeling with recent Lunar Reconnaissance Orbiter Wide-Angle Camera images. We assessed the extent of permanently shadowed regions (PSRs, defined as areas that never receive direct solar illumination), and obtained total areas generally larger than previous studies (12,866 and 16,055 km2, in the north and south respectively).