DOCSLIB.ORG

Some Comparisons of Impact Craters on Mercury and the Moon

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text

Load more

VOL. 80, NO. 17 JOURNAL OF GEOPHYSICAL RESEARCH JUNE 10, 1975 Some Cømparisonsof Impact Craters on Mercury and the Moon DONALD E. GAULT,x JOHN E. GUEST,9' JOHN B. MURRAY,2 DANIEL DZURISIN,a AND MICHAEL C. MALINa Although the general morphologiesof fresh mercurian and lunar craters are remarkably similar, comparisonsof ejectadeposits, interior structures, and changesin morphologywith sizereveal important differencesbetween the two populationsof craters.The differencesare attributableto the differentgravity fieldsin whichthe craterswere formed and have significant implications for theinterpretation of cratering processesand their effectson all planetarybodies. INTRODUCTION impactvelocities, possibly thermal history, etc., may have con- With additionalevidence from the Mariner 10 photography tributed some different effects, but the influenceof these of Mercury[Murray et al., 1974a,b], as Well as the recent radar variablesshould be of second-orderimportance, at best,i n observationsof Venus[Rumsey et al., 1974],it is now firmly es- comparisonwith the gravitationaleffects. There are, for exam- tablishedthat impact crateringhas been a geologicprocess of ple, compellingarguments [Murray et al., 1974b,1975] that the primary significancein the evolution of all the terrestrial fresh mercuriancraters, which are of interestfor comparative planets (and undoubtedlyall planetary objects).The heavily purposes,have been formed in silicatesat least grosslysimilar cratered surfacesof Mercury, the moon, and Mars document to those of the moon and, hence, would provide similar the earliest stagesof their planetary histories,and it is clear physicalproperties and responseduring crateringat the scale that a thoroughunderstanding of crateringprocesses and for- of impact events of interest (diameters greater than a few mation is essentialfor gaining further insightinto the early kilometers).Similarly, although impact velocities in excessof history and subsequent development of all the terrestrial 130 km/s are possiblefor Mercury, the averagemercurian im- planets. Although the early cratering record of earth has been pact velocitiesfor comparativepurposes are probably in the erasedirrevocably and lost by the action of other more active range of 25-30 km/s, within a factor of 2 greaterthan typical geologicprocesses, the recent and relatively young terrestrial lunar values [Wetherill, 1975]. Higher impact velocitieswill impact structureshave been important for an understanding provide increasesin the vapor and melt productsof the mer- and interpretationof lunar (and martian) cratersand cratering curian events,but the effectson the styleof crateringand final processes[e.g., Shoemaker,1962; Baldwin, 1963]. Conversely, crater morphology should be negligible. studies of lunar (martian) craters offer a means for com- It is the purpose of this paper therefore to present first parisonswith terrestrialcraters and crateringphenomena in resultsof somecomparisons of the morphologyof mercurian general [e.g., Hartmann, 1972]. However, suchempirical ap- and lunar cratersin order to explore differencesin cratering proachesto the study and evaluationof crateringon different style and final landforms caused by what are probably planetary bodieshave limitations;impact crateringis a com- predominatelydifferences in gravitational forcesand induced plex physicalprocess that is dependenton many parameters, stresses.In what follows, the morphology and examplesof and unless the functional dependences are known or mercuriancraters which were studiedin detail are followedby recognizedand relationshipsare established,cratering criteria a brief considerationof scaling(crater size) relationships, com- developedfrom cratersformed in one planetaryenvironment parisonsof quantitativemeasurements of ejectadeposits sur- may not be applicable to similar processesand effectsin a rounding craters, comparisonsof statisticsof interior crater different environment. Moreover, erosion of martian and ter- morphologicalelements, and discussionwith implicationsfor restrial craters by agents foreign to the moon has been so planetary cratering in general. severethat it seemsquestionable whether valid comparisons MORPHOLOGY OF MERCURIAN CRATERS can be made between craters on the three bodies; that is, the lack of fresh, sharp impact structureson earth and Mars The morphologyof mercuriancraters is grosslysimilar to precludes,or at leastobscures, evaluation of any differencesin that of lunar craters;i.e., the morphologicelements (rim facies, satelliticcraters, inner terracedwalls, central peak(s)and inner the cratering processesand crater forms arising from differencesin their planetary environment. mountain rings) that characterizelunar impact cratersare all In marked contrast, however, the mercurian craters from associatedwith craterson Mercury. As with the moon, it can the Mariner 10 photography provide comparisonswith lunar be demonstratedthat with increasingage the morphologyof craters under almost ideal 'experimental' conditions.With no cratersbecomes less sharp until most of the crater elementsare appreciableatmosphere having envelopedeither body since barely recognizableand the crater is degradedto a low rim the very earlieststages of their history nor any fluvial action superposedwith large numbersof impact craters.The domi- [Murray et al., 1974b,1975], only one prime crateringvariable nant denudation processis apparently, as on the moon, the has been different between the two crater populations, sameprocess which producedthe original crater, erosionand gravitationalacceleration. Differences in physicalproperties, sedimentationby meteoritic bombardment. The freshestcraters away from the terminator have well- developedand extensivebright ray systems,many of them ex- • Ames ResearchCenter, NASA, Moffett Field, California 94035. 2 University of London Observatory, Mill Hill Park, London, tendingfor hundredsof kilometersand a few extendingin ex- England. cessof 1000 km (Figure 1). Some cratersare also surrounded 3 Division of Geological and PlanetarySciences, California Institute by dark halos resemblingthose associatedwith such lunar of Technology, Pasadena, California 91109. craters as Tycho and Aristarchus; these are best seennear the Copyright¸ 1975by the AmericanGeophysical Union. limb underconditions approaching zero phaselighting. Other 2444 GAULT ET AL..' MARINER 10 MISSION 2445 .. %'•-•-".......•.- }, •. :-'"•:•:•,? :'7'.;.::'•.':'.7 '.': '., ' .•:•::':""....:-•3•.....--.:>•:•"•', • •,'" .:.-....-•.-'•< ,- ...... ., •...:.:•,• ': ..>Y:'•.•::•........... .... -. %' • ", .. C" :.-...... •'....•:: ?• '...:......•::•.,•: •.'•.' .'-.•. • '• •'• :--:•:•....:.•f: •.-....... •.•::•".:' .'.•..• .. ':', , :•.• , .• ' ..... ., . .?½:y....::..: :. ..•,..• . ., ,. r•:••.... ,.• :5' • "'. • -:'.:•.½ , ,:' ...."'::' ,.-•" ':'"•....• ":• : )• •' .•;•:..:.,•? ..•.:..:-•::.•. :..•,..::•..;.:-•::•.•) t. •,. ... • , -7:.•':.:..:•-.,.......•.;..... .:• • ,. •.• ., , • '• .... ..:.) .•....... ß . • :•.."•.,.,. •..: ....•.•,-•.-.... t::: "'•;•6::.::....,:•:?:"•• .." •,...... ,.'•'.' •..... .• - ........ -:•-:t ;::...:.:...... .•...• ..... , :::' '" ::::•'"'• :•..* . '.c': 4"•: -. ::• ..:'.-;: ..-½::...,•.• .......:., >,.,.. • .. , •, • .: -•, :::::•:•:.....•;•:•........ :--.:-:. .......:•:•:. :•..•.:.:: g:•'-.½ :•.•..-...::-,:•..,..-..' t•.--,-•y½ •% ,3•.....:•' ,.-, • ' ,, :'•.-•;:•::.-:... :;:• ..:':.•....-;•::•., - •,.,.. >.•,•............ ,.. ;.• ::.:••,:•;• ..:•,•,•1 • ..•:.. .,::•:•.-• %..':•::...::• •. ½•,.., ,.... ,. •:.'•. ':::- ••-•:•_•: • .? "• :• 2.•:, -•7: ;:: :?•" .:• ....::•'":":'s- ....•'•:•-..•'.•-:•.•''•t'::"•_&•: "-.. .• I -•:...,.-•:?"•:,• •. '..,,:,:• ' ':' '-" •"' .•...:• '7?Z.:f::"::*.'.'* ":'•:-•4'::•:•' :':*'.. .... '::,•¾•'--:';•,...,•.• :•: G-f?.•', '?-•'"' ."'" ': ....'•':'..,':•- •:'•:::/•:::•' :s'•:-.:':-•;•;- •:",-. •'•':• - ' ::•..:2..... :•:.. ""*-'':-• L .•f.• .. .•--::•, ' . :- .................... •::•:•:.:..-• •f:-•• •-.•• ,•: ,-:•.•' ..-• ::.•::..•::,.:.• .... :,•?.•::•.,:' :}•:>,...:::•.• ß .... •::::•':•:•:•::*':k:•,,.:.: 3-...::..Li[ ,•'•.:: "::..> ............ • .:::½,,:.:•:::•...•,.:.-•.:. ::•;:::.•:.-•::.•::.,• '-'::•:•.....•. .[:••..:- :....• ..........•:::•.... :,•!• ....•: .:,•.:• ,.•,•..•-•..' ,, ., '::"• • • :••:•:• ...........• "-:; • -:...... /• •-• •:• ., • ..... •; • .... •:. .•::..•:,:::-:• -.•,•:• •::•:• _ :.:•::.•4!'::'::•:• ' •..--•;.• :'::•.7 :':•-.': ' :"'•'," .....===============================.... - •:•-•:•'• "•:"' :k'"•"'•;•: ':'•:" .....-:.::•....... :::- • ;.•,:•-,,...•:•;•:• :,. •..-• ...... ....::: ....... Fig. la. Preencounterview of planet with eveningterminator. Fig. 1. Photomosaicsof Mercuryshowing location of cratersselected for detailedstudy of their morphologyand ejecta deposits. Coordinates and diameters of craters are listed in Table 1. 2446 GAULT ET AL.: MARINER 10 MISSION .• ß,, ,, .½'j.:r':f.;.½•..'½ :•* ...?'..• ......•.:.•:::½ .•..: ':"{'""'":;J'-'• -:--?;•...--.-.-:•.•.'.;•:,,,- •. •• "• '24 ":'e' '':"; ';":::'::,,' ;;::"{ZI:•;:;• '.................. •-•,•--•-•%?M:! , .--.'½"½:'""• :......::?'[.. •%:•:•;•'•":*: ':•:.•-':-•:""-"..:• ': ....... ..... "" -;L'.• •i•'*-"' :x"'Z:,..,.: -•" ...... •.-:,.&•?-':':'L<•f.•..:•::•--• ....: ½• •,• • . ,•-:.•--., :•' •"-:-'-.'-. ..'•'..:::'.;?':z:a"'"'.,•.•....??•..•:,.:,•:? ...:?, %..':::..:':;•;?• -•.•..• •. :?..-.......,? c::.•'• .... .-.;½;.•;:..; .:.?:.. , . ., ..,.•...'.•;.•':.?:, .•..-::?. ß.... .......... -- •,.:....,,...•: ,•. ......,..•:.. ............,.½....... ., ß• •-%. , • x
Recommended publications
  • Washington Division of Geology and Earth Resources Open File Report

    Washington Division of Geology and Earth Resources Open File Report

    l 122 EARTHQUAKES AND SEISMOLOGY - LEGAL ASPECTS OPEN FILE REPORT 92-2 EARTHQUAKES AND Ludwin, R. S.; Malone, S. D.; Crosson, R. EARTHQUAKES AND SEISMOLOGY - LEGAL S.; Qamar, A. I., 1991, Washington SEISMOLOGY - 1946 EVENT ASPECTS eanhquak:es, 1985. Clague, J. J., 1989, Research on eanh- Ludwin, R. S.; Qamar, A. I., 1991, Reeval­ Perkins, J. B.; Moy, Kenneth, 1989, Llabil­ quak:e-induced ground failures in south­ uation of the 19th century Washington ity of local government for earthquake western British Columbia [abstract). and Oregon eanhquake catalog using hazards and losses-A guide to the law Evans, S. G., 1989, The 1946 Mount Colo­ original accounts-The moderate sized and its impacts in the States of Califor­ nel Foster rock avalanches and auoci­ earthquake of May l, 1882 [abstract). nia, Alaska, Utah, and Washington; ated displacement wave, Vancouver Is­ Final repon. Maley, Richard, 1986, Strong motion accel­ land, British Columbia. erograph stations in Oregon and Wash­ Hasegawa, H. S.; Rogers, G. C., 1978, EARTHQUAKES AND ington (April 1986). Appendix C Quantification of the magnitude 7.3, SEISMOLOGY - NETWORKS Malone, S. D., 1991, The HAWK seismic British Columbia earthquake of June 23, AND CATALOGS data acquisition and analysis system 1946. [abstract). Berg, J. W., Jr.; Baker, C. D., 1963, Oregon Hodgson, E. A., 1946, British Columbia eanhquak:es, 1841 through 1958 [ab­ Milne, W. G., 1953, Seismological investi­ earthquake, June 23, 1946. gations in British Columbia (abstract). stract). Hodgson, J. H.; Milne, W. G., 1951, Direc­ Chan, W.W., 1988, Network and array anal­ Munro, P. S.; Halliday, R. J.; Shannon, W.
  • Railway Employee Records for Colorado Volume Iii

    Railway Employee Records for Colorado Volume Iii

    RAILWAY EMPLOYEE RECORDS FOR COLORADO VOLUME III By Gerald E. Sherard (2005) When Denver’s Union Station opened in 1881, it saw 88 trains a day during its gold-rush peak. When passenger trains were a popular way to travel, Union Station regularly saw sixty to eighty daily arrivals and departures and as many as a million passengers a year. Many freight trains also passed through the area. In the early 1900s, there were 2.25 million railroad workers in America. After World War II the popularity and frequency of train travel began to wane. The first railroad line to be completed in Colorado was in 1871 and was the Denver and Rio Grande Railroad line between Denver and Colorado Springs. A question we often hear is: “My father used to work for the railroad. How can I get information on Him?” Most railroad historical societies have no records on employees. Most employment records are owned today by the surviving railroad companies and the Railroad Retirement Board. For example, most such records for the Union Pacific Railroad are in storage in Hutchinson, Kansas salt mines, off limits to all but the lawyers. The Union Pacific currently declines to help with former employee genealogy requests. However, if you are looking for railroad employee records for early Colorado railroads, you may have some success. The Colorado Railroad Museum Library currently has 11,368 employee personnel records. These Colorado employee records are primarily for the following railroads which are not longer operating. Atchison, Topeka & Santa Fe Railroad (AT&SF) Atchison, Topeka and Santa Fe Railroad employee records of employment are recorded in a bound ledger book (record number 736) and box numbers 766 and 1287 for the years 1883 through 1939 for the joint line from Denver to Pueblo.
  • Ices on Mercury: Chemistry of Volatiles in Permanently Cold Areas of Mercury’S North Polar Region

    Ices on Mercury: Chemistry of Volatiles in Permanently Cold Areas of Mercury’S North Polar Region

    Icarus 281 (2017) 19–31 Contents lists available at ScienceDirect Icarus journal homepage: www.elsevier.com/locate/icarus Ices on Mercury: Chemistry of volatiles in permanently cold areas of Mercury’s north polar region ∗ M.L. Delitsky a, , D.A. Paige b, M.A. Siegler c, E.R. Harju b,f, D. Schriver b, R.E. Johnson d, P. Travnicek e a California Specialty Engineering, Pasadena, CA b Dept of Earth, Planetary and Space Sciences, University of California, Los Angeles, CA c Planetary Science Institute, Tucson, AZ d Dept of Engineering Physics, University of Virginia, Charlottesville, VA e Space Sciences Laboratory, University of California, Berkeley, CA f Pasadena City College, Pasadena, CA a r t i c l e i n f o a b s t r a c t Article history: Observations by the MESSENGER spacecraft during its flyby and orbital observations of Mercury in 2008– Received 3 January 2016 2015 indicated the presence of cold icy materials hiding in permanently-shadowed craters in Mercury’s Revised 29 July 2016 north polar region. These icy condensed volatiles are thought to be composed of water ice and frozen Accepted 2 August 2016 organics that can persist over long geologic timescales and evolve under the influence of the Mercury Available online 4 August 2016 space environment. Polar ices never see solar photons because at such high latitudes, sunlight cannot Keywords: reach over the crater rims. The craters maintain a permanently cold environment for the ices to persist. Mercury surface ices magnetospheres However, the magnetosphere will supply a beam of ions and electrons that can reach the frozen volatiles radiolysis and induce ice chemistry.
  • Mercury's Low-Reflectance Material: Constraints from Hollows

    Mercury's Low-Reflectance Material: Constraints from Hollows

    Mercury’s low-reflectance material: Constraints from hollows Rebecca Thomas, Brian Hynek, David Rothery, Susan Conway To cite this version: Rebecca Thomas, Brian Hynek, David Rothery, Susan Conway. Mercury’s low-reflectance material: Constraints from hollows. Icarus, Elsevier, 2016, 277, pp.455-465. 10.1016/j.icarus.2016.05.036. hal-02271739 HAL Id: hal-02271739 https://hal.archives-ouvertes.fr/hal-02271739 Submitted on 27 Aug 2019 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Mercury’s Low-Reflectance Material: Constraints from Hollows Rebecca J. Thomas , Brian M. Hynek , David A. Rothery , Susan J. Conway PII: S0019-1035(16)30246-9 DOI: 10.1016/j.icarus.2016.05.036 Reference: YICAR 12084 To appear in: Icarus Received date: 23 February 2016 Revised date: 9 May 2016 Accepted date: 24 May 2016 Please cite this article as: Rebecca J. Thomas , Brian M. Hynek , David A. Rothery , Susan J. Conway , Mercury’s Low-Reflectance Material: Constraints from Hollows, Icarus (2016), doi: 10.1016/j.icarus.2016.05.036 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript.
  • Bepicolombo - a Mission to Mercury

    Bepicolombo - a Mission to Mercury

    BEPICOLOMBO - A MISSION TO MERCURY ∗ R. Jehn , J. Schoenmaekers, D. Garc´ıa and P. Ferri European Space Operations Centre, ESA/ESOC, Darmstadt, Germany ABSTRACT BepiColombo is a cornerstone mission of the ESA Science Programme, to be launched towards Mercury in July 2014. After a journey of nearly 6 years two probes, the Magneto- spheric Orbiter (JAXA) and the Planetary Orbiter (ESA) will be separated and injected into their target orbits. The interplanetary trajectory includes flybys at the Earth, Venus (twice) and Mercury (four times), as well as several thrust arcs provided by the solar electric propulsion module. At the end of the transfer a gravitational capture at the weak stability boundary is performed exploiting the Sun gravity. In case of a failure of the orbit insertion burn, the spacecraft will stay for a few revolutions in the weakly captured orbit. The arrival conditions are chosen such that backup orbit insertion manoeuvres can be performed one, four or five orbits later with trajectory correction manoeuvres of less than 15 m/s to compensate the Sun perturbations. Only in case that no manoeuvre can be performed within 64 days (5 orbits) after the nominal orbit insertion the spacecraft will leave Mercury and the mission will be lost. The baseline trajectory has been designed taking into account all operational constraints: 90-day commissioning phase without any thrust; 30-day coast arcs before each flyby (to allow for precise navigation); 7-day coast arcs after each flyby; 60-day coast arc before orbit insertion; Solar aspect angle constraints and minimum flyby altitudes (300 km at Earth and Venus, 200 km at Mercury).
  • The Search for Another Earth – Part II

    The Search for Another Earth – Part II

    GENERAL ARTICLE The Search for Another Earth – Part II Sujan Sengupta In the first part, we discussed the various methods for the detection of planets outside the solar system known as the exoplanets. In this part, we will describe various kinds of exoplanets. The habitable planets discovered so far and the present status of our search for a habitable planet similar to the Earth will also be discussed. Sujan Sengupta is an 1. Introduction astrophysicist at Indian Institute of Astrophysics, Bengaluru. He works on the The first confirmed exoplanet around a solar type of star, 51 Pe- detection, characterisation 1 gasi b was discovered in 1995 using the radial velocity method. and habitability of extra-solar Subsequently, a large number of exoplanets were discovered by planets and extra-solar this method, and a few were discovered using transit and gravi- moons. tational lensing methods. Ground-based telescopes were used for these discoveries and the search region was confined to about 300 light-years from the Earth. On December 27, 2006, the European Space Agency launched 1The movement of the star a space telescope called CoRoT (Convection, Rotation and plan- towards the observer due to etary Transits) and on March 6, 2009, NASA launched another the gravitational effect of the space telescope called Kepler2 to hunt for exoplanets. Conse- planet. See Sujan Sengupta, The Search for Another Earth, quently, the search extended to about 3000 light-years. Both Resonance, Vol.21, No.7, these telescopes used the transit method in order to detect exo- pp.641–652, 2016. planets. Although Kepler’s field of view was only 105 square de- grees along the Cygnus arm of the Milky Way Galaxy, it detected a whooping 2326 exoplanets out of a total 3493 discovered till 2Kepler Telescope has a pri- date.
  • Shallow Crustal Composition of Mercury As Revealed by Spectral Properties and Geological Units of Two Impact Craters

    Shallow Crustal Composition of Mercury As Revealed by Spectral Properties and Geological Units of Two Impact Craters

    Planetary and Space Science 119 (2015) 250–263 Contents lists available at ScienceDirect Planetary and Space Science journal homepage: www.elsevier.com/locate/pss Shallow crustal composition of Mercury as revealed by spectral properties and geological units of two impact craters Piero D’Incecco a,n, Jörn Helbert a, Mario D’Amore a, Alessandro Maturilli a, James W. Head b, Rachel L. Klima c, Noam R. Izenberg c, William E. McClintock d, Harald Hiesinger e, Sabrina Ferrari a a Institute of Planetary Research, German Aerospace Center, Rutherfordstrasse 2, D-12489 Berlin, Germany b Department of Geological Sciences, Brown University, Providence, RI 02912, USA c The Johns Hopkins University Applied Physics Laboratory, Laurel, MD 20723, USA d Laboratory for Atmospheric and Space Physics, University of Colorado, Boulder, CO 80303, USA e Westfälische Wilhelms-Universität Münster, Institut für Planetologie, Wilhelm-Klemm Str. 10, D-48149 Münster, Germany article info abstract Article history: We have performed a combined geological and spectral analysis of two impact craters on Mercury: the Received 5 March 2015 15 km diameter Waters crater (106°W; 9°S) and the 62.3 km diameter Kuiper crater (30°W; 11°S). Using Received in revised form the Mercury Dual Imaging System (MDIS) Narrow Angle Camera (NAC) dataset we defined and mapped 9 October 2015 several units for each crater and for an external reference area far from any impact related deposits. For Accepted 12 October 2015 each of these units we extracted all spectra from the MESSENGER Atmosphere and Surface Composition Available online 24 October 2015 Spectrometer (MASCS) Visible-InfraRed Spectrograph (VIRS) applying a first order photometric correc- Keywords: tion.
  • Mariner to Mercury, Venus and Mars

    Mariner to Mercury, Venus and Mars

    NASA Facts National Aeronautics and Space Administration Jet Propulsion Laboratory California Institute of Technology Pasadena, CA 91109 Mariner to Mercury, Venus and Mars Between 1962 and late 1973, NASA’s Jet carry a host of scientific instruments. Some of the Propulsion Laboratory designed and built 10 space- instruments, such as cameras, would need to be point- craft named Mariner to explore the inner solar system ed at the target body it was studying. Other instru- -- visiting the planets Venus, Mars and Mercury for ments were non-directional and studied phenomena the first time, and returning to Venus and Mars for such as magnetic fields and charged particles. JPL additional close observations. The final mission in the engineers proposed to make the Mariners “three-axis- series, Mariner 10, flew past Venus before going on to stabilized,” meaning that unlike other space probes encounter Mercury, after which it returned to Mercury they would not spin. for a total of three flybys. The next-to-last, Mariner Each of the Mariner projects was designed to have 9, became the first ever to orbit another planet when two spacecraft launched on separate rockets, in case it rached Mars for about a year of mapping and mea- of difficulties with the nearly untried launch vehicles. surement. Mariner 1, Mariner 3, and Mariner 8 were in fact lost The Mariners were all relatively small robotic during launch, but their backups were successful. No explorers, each launched on an Atlas rocket with Mariners were lost in later flight to their destination either an Agena or Centaur upper-stage booster, and planets or before completing their scientific missions.
  • Case Fil Copy

    Case Fil Copy

    NASA TECHNICAL NASA TM X-3511 MEMORANDUM CO >< CASE FIL COPY REPORTS OF PLANETARY GEOLOGY PROGRAM, 1976-1977 Compiled by Raymond Arvidson and Russell Wahmann Office of Space Science NASA Headquarters NATIONAL AERONAUTICS AND SPACE ADMINISTRATION • WASHINGTON, D. C. • MAY 1977 1. Report No. 2. Government Accession No. 3. Recipient's Catalog No. TMX3511 4. Title and Subtitle 5. Report Date May 1977 6. Performing Organization Code REPORTS OF PLANETARY GEOLOGY PROGRAM, 1976-1977 SL 7. Author(s) 8. Performing Organization Report No. Compiled by Raymond Arvidson and Russell Wahmann 10. Work Unit No. 9. Performing Organization Name and Address Office of Space Science 11. Contract or Grant No. Lunar and Planetary Programs Planetary Geology Program 13. Type of Report and Period Covered 12. Sponsoring Agency Name and Address Technical Memorandum National Aeronautics and Space Administration 14. Sponsoring Agency Code Washington, D.C. 20546 15. Supplementary Notes 16. Abstract A compilation of abstracts of reports which summarizes work conducted by Principal Investigators. Full reports of these abstracts were presented to the annual meeting of Planetary Geology Principal Investigators and their associates at Washington University, St. Louis, Missouri, May 23-26, 1977. 17. Key Words (Suggested by Author(s)) 18. Distribution Statement Planetary geology Solar system evolution Unclassified—Unlimited Planetary geological mapping Instrument development 19. Security Qassif. (of this report) 20. Security Classif. (of this page) 21. No. of Pages 22. Price* Unclassified Unclassified 294 $9.25 * For sale by the National Technical Information Service, Springfield, Virginia 22161 FOREWORD This is a compilation of abstracts of reports from Principal Investigators of NASA's Office of Space Science, Division of Lunar and Planetary Programs Planetary Geology Program.
  • March 21–25, 2016

    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,
  • Impact Melt Emplacement on Mercury

    Impact Melt Emplacement on Mercury

    Western University Scholarship@Western Electronic Thesis and Dissertation Repository 7-24-2018 2:00 PM Impact Melt Emplacement on Mercury Jeffrey Daniels The University of Western Ontario Supervisor Neish, Catherine D. The University of Western Ontario Graduate Program in Geology A thesis submitted in partial fulfillment of the equirr ements for the degree in Master of Science © Jeffrey Daniels 2018 Follow this and additional works at: https://ir.lib.uwo.ca/etd Part of the Geology Commons, Physical Processes Commons, and the The Sun and the Solar System Commons Recommended Citation Daniels, Jeffrey, "Impact Melt Emplacement on Mercury" (2018). Electronic Thesis and Dissertation Repository. 5657. https://ir.lib.uwo.ca/etd/5657 This Dissertation/Thesis is brought to you for free and open access by Scholarship@Western. It has been accepted for inclusion in Electronic Thesis and Dissertation Repository by an authorized administrator of Scholarship@Western. For more information, please contact [email protected]. Abstract Impact cratering is an abrupt, spectacular process that occurs on any world with a solid surface. On Earth, these craters are easily eroded or destroyed through endogenic processes. The Moon and Mercury, however, lack a significant atmosphere, meaning craters on these worlds remain intact longer, geologically. In this thesis, remote-sensing techniques were used to investigate impact melt emplacement about Mercury’s fresh, complex craters. For complex lunar craters, impact melt is preferentially ejected from the lowest rim elevation, implying topographic control. On Venus, impact melt is preferentially ejected downrange from the impact site, implying impactor-direction control. Mercury, despite its heavily-cratered surface, trends more like Venus than like the Moon.
  • Downloaded for Personal Non-Commercial Research Or Study, Without Prior Permission Or Charge

    Downloaded for Personal Non-Commercial Research Or Study, Without Prior Permission Or Charge

    MacArtney, Adrienne (2018) Atmosphere crust coupling and carbon sequestration on early Mars. PhD thesis. http://theses.gla.ac.uk/9006/ Copyright and moral rights for this work are retained by the author A copy can be downloaded for personal non-commercial research or study, without prior permission or charge This work cannot be reproduced or quoted extensively from without first obtaining permission in writing from the author The content must not be changed in any way or sold commercially in any format or medium without the formal permission of the author When referring to this work, full bibliographic details including the author, title, awarding institution and date of the thesis must be given Enlighten:Theses http://theses.gla.ac.uk/ [email protected] ATMOSPHERE - CRUST COUPLING AND CARBON SEQUESTRATION ON EARLY MARS By Adrienne MacArtney B.Sc. (Honours) Geosciences, Open University, 2013. Submitted in partial fulfilment of the requirements for the degree of Doctor of Philosophy at the UNIVERSITY OF GLASGOW 2018 © Adrienne MacArtney All rights reserved. The author herby grants to the University of Glasgow permission to reproduce and redistribute publicly paper and electronic copies of this thesis document in whole or in any part in any medium now known or hereafter created. Signature of Author: 16th January 2018 Abstract Evidence exists for great volumes of water on early Mars. Liquid surface water requires a much denser atmosphere than modern Mars possesses, probably predominantly composed of CO2. Such significant volumes of CO2 and water in the presence of basalt should have produced vast concentrations of carbonate minerals, yet little carbonate has been discovered thus far.