DOCSLIB.ORG

170221 Sps, Phase-Standing Whistler

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
170221 Sps, Phase-Standing Whistler Symposium on Planetary Science 2017, February 20−21, Sendai Phase-standing whistler fuctuations detected by SELENE and ARTEMIS around the Moon Yasunori Tsugawa1, Y. Katoh2, N. Terada2, and S. Machida1 1Institute for Space-Earth Environmental Research, Nagoya University 2Department of Geophysics, Tohoku University Abstract Low frequency (<~0.01 Hz) magnetic fluctuations around the Moon in the solar wind have been reported since 1960s. They are extended upstream of the lunar wake edge along the interplanetary magnetic field lines. We analyze magnetic field data detected by SELENE and ARTEMIS to reveal generation processes of the fluctuations. Our analyses indicate that observed polarizations of the magnetic fluctuations are determined by the spacecraft velocity: right-hand polarization when S/C moves downstream, left-hand polarization when S/ C moves upstream. This fact suggests that their phase velocity in the Moon frame is smaller than the spacecraft velocity and they are R-mode in plasma frame, i.e., they are phase-standing whistlers. They are possibly generated as bow waves around the lunar crustal magnetic anomalies and/ or ballistic fluctuations carried by electrons modified through the wake. 6432 NESS AND SCHATTEN INTERPLANETARY MAGNETIC FIELD FLUCTUATIONSverse to the average6429 field direction. The noise appearance indicative of a convective phe- regions represent relatively large amplitude per- nomenon associated with the solar wind flow DFA is the Distance to the extended field craft position thatturbations is downstream where magnitudes from of the transverse past the moon. X perturbations in(XW interplanetary space increase line From the 888 Axis. the lunar wake intersect position < STATISTICAL STUDIES DCA is the Distance along the field line from Xsc). by a factor of 1.4-1.7, whereas the longitudinal component 'is increased by an order of magni- the spacecraft to the point of Closest Histograms of the occurrence of noise as a The above parameters willtude. be usedIn the in verythe follow- quiet umbra! core the trans- function of the parameters DFA and DCA are Approach to the axis of the wake verse and longitudinal perturbations are re- shown in Figure 8. The data used in this figure (DCA= Xsa- X.,). ing discussions of detailed passes and statistical analysis of the spatial occurrenceduced by ofan rapid order fluc- of magnitude from the were obtained from sequence averages over an XW is the XssE coordinate of the position undisturbed interplanetary medium. interval of 81.8 seconds. The histograms of noise along the field line where the inter- tuations. All distances will Thebe inspatial units extentof lunar of rapid fluctuations ob- occurrence as a function of DFA illustrate a section with the theoretical lunar Wake radii. served by Explorer 35 from July 1967 through generally flat appearance out to approximately occurs. Figure 5 shows a seriesJuly of 1968 three is shownadditional in Figure 7. The position of 1 lunar radius and then a. rapid decrease. This DW is the Distance along the field line from passes through the lunar thewake spacecraft in which where obser- the field fluctuations were graph substaritiates the hypothesis that the the spacecraft to the lunar Wake surface vations of rapid field fluctuationsobserved werehas been made rotated by above the moon-sun field fluctuations occur only on those field lines axis into the selenocentrie solar ecliptic plane. that pass through the spacecraft and the lunar intersection XW. Values of this quantity Explorer 35. Universal time and spacecraft position in selenocentric Fromcoordinates this figure are thetabu- extent of the fluctuating plasma penumbra. In addition, there is only a greater than 0 are defined to indicate field region may be determined. It is seen that slight increased occurrence of fluctuations with that the spacecraft is upstream from lated along each abscissa. Inthe addition, disturbances the are shaded observed far from the moon deeper umbra! penetration by the field lines. the position where the field line crosses regions indicate those timesboth when in the the Y fielddirection line and also upstream of This supports the hypothesis that the noise is the wake (Xsc > XW), and conversely that passes through the spacecraftthe wake. Thisalso indicatesthreads that the propagation associated with those field lines that intersect a negative value is indicative of a space- . the lunar wake as definedvelocity by the ofcriterion these fluctuations DF A has a component the penumbra and is not associated with the traveling perpendicular to the solar wind direc- umbra! core of the lunar wake. tion relatively fast as compared with the solar An important parameter that sh,ould be wind speed itself. The spatial extent of the dis- studied is the plasma {3 value and other micro- Low freq. fuctuationturbances around does not possess any shock wake wave scopic characteristics edge of the interplanetary me- 6426 NESS AND SCHATTEN S•IO +•lll5" < INY)PEN. < 0.01- INYisw - O.SS 0800 213 102 !16 2.9 1.7 2.0 3.2 r--NOISE ----j 26 APRIL 1968 II 5 0!100 0600 0700 SOLAR WIND 222 110 !14 3.0 1.8 1.9 3.1 NOISY REGIONS 20 Fig. 1. Diagram of the umbral and penumbral regions formed due to the absorption of the solar wind by the moon. A sample orbit of Explorer 35 is shown, as are the regions of space where rapid fluctuations of the interplanetary magnetic field are observed. The27 direction APRIL 1968 of the electricr-NOISE--i field, necessary to maintain charge neutrality, isr-NOISE-----l also indicated. F 10 .. , '""""'r'r'' \ .....,.,/' ......... o.,crOit v 01 tions are not observed in the solar wind umbra! nitude and detectable decreases Fig.in the 7. penum-Spacecraft positions, when rapid fluctuations were observed, rotated about the Xss• ... 0 0.!1 core of the lunar.,.,J., shadow but• 1.!1appear 0 to exist bral region identified, respectively, by1'1 +2 and - axis into the X s.-Yss• plane. 0 .. ..... ... J 8 both upstreamI and downstream of theI pen- signs on the magnitudeI plot. The averageI direc- umbralTIME shadow0300 of the moon. Simultaneous0400 tion of the 0!500interplanetary magnetic field,0600 the [Ness and Schatten et al., 1969] plasma+SSE data 282 were not available for correlative227 spacecraft orbit,117 and the direction to the!1!1 earth analysis,RAD and3.1 it is assumed that the 2.2magnetic are shown in 1.8the upper left-hand corner.3.0 At field magnitude anomalies [Colburn et al., 1967; this time the satellite Explorer 33 is located NessFig. et5. al.,Observations 1967, 1968; andof fieldTaylor magnitude et al., 1968] by Explorerat XBB = 35 27.3 for Rs, 3 passesYss = during7.5 Rs, ZssApril = 25-27,-4.5 magnetic fluctuations < 5 Hz <f>detected by Explorer 35 [Ness et al., 1967, 1968; Taylor et al., 1968] 1968.indicate Universal the location time, ofselenocentric the solar plasma radius, umbra and Rs,angle while are Explorershown on 35 theis located abscissa. at TheXss =shaded 56.5 regions are indicative that the field line that passes by the spacecraft threads the lunar and penumbra. SO wake region. The numbers above the abscissa representRs, Yss the = distance -24.3 Rs, DCA. Zss = -3.4 Rs, that • onOne magnetic condition necessary field for linesthe observation which a separation cross ofthe 43.2 Rslunar between wake the two space- of these fluctuations is that the magnetic field craft exists. These simultaneous data illustrate • slightlyline passing throughmore the transverse spacecraft must alsothan an longitudinal important feature of cislunar space, namely, pass through the lunar penumbral region. The that on the average the interplanetary magnetic spatial extent,· relative amplitude, -direction, and field is relatively uniform over this distance • extendsolar wind propertiesup/downstream that favor the occurrence for >1000scale for timekm scales from of 30 theminutes wake or more. → travelling speed ≧ solar wind speed and observation of these fluctuations will be In Figure 3 are presented simultaneous obser- presented. vations of magnitude measurements at 5.11- second intervals obtained by both spacecraft ExPERIMENTAL OBsERVATIONs during the March 26, 1968, pass illustrated pre- Simultaneous observations of the interplane- viously in Figure 2. Identified on the Explorer tary magnetic field on March 26, 1968, by Ex- 35 data are noisy and quiet regions of the plorers 33 and 35 are shown in Figure 2. While magnetic field. The presence of a quasi-sinu- Explorer 33 is measuring the interplanetary soidal variation in the field magnitude on Ex- magnetic field, Explorer 35 is in loose orbit plorer 35 is spurious and associated with the about the moon. Observations on Explorer 33 aliased spin period of the spacecraft and the measure a rather steady field with magnitude incomplete removal of spin modulation associated 6 y. The observations by Explorer 35 reveal with zero level and gain uncertainty of the two the presence of an umbra! increase in field mag- sensors transverse to the spin axis of the space- if ωobs ~ -k•Vsc, ARTEMIS event λ ~ 1.5 km/s / 0.01 Hz = 150 km → comparable to MA scale 2012/07/26 6 P1 B vectors P2 3 ) M (R 0 SSE Y -3 ionmom P1 if leading edge is determined by Vg_max, P2 Vg_max ≳ VSW tan 65° = 680 km/s → correspond to whistler-mode waves -6 -6 -3 0 3 6 XSSE (RM) • inbound: RH, outbound: LH opposite even at the same time & space → Doppler-shift by s/c velocity • from terminator to upstream of expansion region ionmom → larger Vg than fast MS velocity SELENE event 1 equator • ~100 km altitudes • in the solar wind (SW) • Alfven Mach number, MA ~ 8 • polarized fluctuations <~0.01 Hz • from dayside ~SZA60° to outer wake • LH inbound to wake • RH outbound from wake SELENE event 2 • ~100 km altitudes • in SW • higher Mach number, MA ~ 16 • polarized components <~0.1 Hz in disturbed field • from terminator to inner wake • LH inbound to wake • RH outbound from wake Statistical properties, SELENE 60 0.6 R 100 X−Y LSM 100 X−Z SCO 45 0.3 50 50 • RH when s/c goes (km) (km) 0 30 0 0 downstream LSM SCO Y Z • LH when s/c goes Vsc Average ellipticity -50 Occurrence rate (%) -50 15 -0.3 upstream -100 YLSM = sig(B · XSSE)(B × XSSE), -100 YSCO = sig(Pos_XSSE)(Vsc × XSSE), L |ZLSM| < 1000 km, R = alt.
Load more

Recommended publications
  • Solar-Wind Proton Access Deep Into the Near-Moon Wake M
    GEOPHYSICAL RESEARCH LETTERS, VOL. 36, L16103, doi:10.1029/2009GL039444, 2009 Click Here for Full Article Solar-wind proton access deep into the near-Moon wake M. N. Nishino,1 M. Fujimoto,1 K. Maezawa,1 Y. Saito,1 S. Yokota,1 K. Asamura,1 T. Tanaka,1 H. Tsunakawa,2 M. Matsushima,2 F. Takahashi,2 T. Terasawa,2 H. Shibuya,3 and H. Shimizu4 Received 3 June 2009; revised 22 July 2009; accepted 24 July 2009; published 28 August 2009. [1] We study solar wind (SW) entry deep into the near- wake were not known because there were no observation Moon wake using SELENE (KAGUYA) data. It has been data. Recently, a Japanese lunar orbiter SELENE known that SW protons flowing around the Moon access (KAGUYA) performed comprehensive measurements of the central region of the distant lunar wake, while their the plasma and electromagnetic environment around the intrusion deep into the near-Moon wake has never been Moon; in particular, entry of SW protons into the near- expected. We show that SW protons sneak into the deepest Moon wake was found [Nishino et al., 2009]. The SW lunar wake (anti-subsolar region at 100 km altitude), and protons are accelerated by the bipolar electric field around that the entry yields strong asymmetry of the near-Moon the wake boundary and come into the near-Moon wake by wake environment. Particle trajectory calculations their Larmor motion in the direction perpendicular to the demonstrate that these SW protons are once scattered at IMF. This entry mechanism, which we call ‘Type-I entry’, the lunar dayside surface, picked-up by the SW motional lets the SW protons come fairly deep into the wake (solar electric field, and finally sneak into the deepest wake.
    [Show full text]
  • Mars Express Orbiter Radio Science
    MaRS: Mars Express Orbiter Radio Science M. Pätzold1, F.M. Neubauer1, L. Carone1, A. Hagermann1, C. Stanzel1, B. Häusler2, S. Remus2, J. Selle2, D. Hagl2, D.P. Hinson3, R.A. Simpson3, G.L. Tyler3, S.W. Asmar4, W.I. Axford5, T. Hagfors5, J.-P. Barriot6, J.-C. Cerisier7, T. Imamura8, K.-I. Oyama8, P. Janle9, G. Kirchengast10 & V. Dehant11 1Institut für Geophysik und Meteorologie, Universität zu Köln, D-50923 Köln, Germany Email: [email protected] 2Institut für Raumfahrttechnik, Universität der Bundeswehr München, D-85577 Neubiberg, Germany 3Space, Telecommunication and Radio Science Laboratory, Dept. of Electrical Engineering, Stanford University, Stanford, CA 95305, USA 4Jet Propulsion Laboratory, 4800 Oak Grove Drive, Pasadena, CA 91009, USA 5Max-Planck-Instuitut für Aeronomie, D-37189 Katlenburg-Lindau, Germany 6Observatoire Midi Pyrenees, F-31401 Toulouse, France 7Centre d’etude des Environnements Terrestre et Planetaires (CETP), F-94107 Saint-Maur, France 8Institute of Space & Astronautical Science (ISAS), Sagamihara, Japan 9Institut für Geowissenschaften, Abteilung Geophysik, Universität zu Kiel, D-24118 Kiel, Germany 10Institut für Meteorologie und Geophysik, Karl-Franzens-Universität Graz, A-8010 Graz, Austria 11Observatoire Royal de Belgique, B-1180 Bruxelles, Belgium The Mars Express Orbiter Radio Science (MaRS) experiment will employ radio occultation to (i) sound the neutral martian atmosphere to derive vertical density, pressure and temperature profiles as functions of height to resolutions better than 100 m, (ii) sound
    [Show full text]
  • Information Summaries
    TIROS 8 12/21/63 Delta-22 TIROS-H (A-53) 17B S National Aeronautics and TIROS 9 1/22/65 Delta-28 TIROS-I (A-54) 17A S Space Administration TIROS Operational 2TIROS 10 7/1/65 Delta-32 OT-1 17B S John F. Kennedy Space Center 2ESSA 1 2/3/66 Delta-36 OT-3 (TOS) 17A S Information Summaries 2 2 ESSA 2 2/28/66 Delta-37 OT-2 (TOS) 17B S 2ESSA 3 10/2/66 2Delta-41 TOS-A 1SLC-2E S PMS 031 (KSC) OSO (Orbiting Solar Observatories) Lunar and Planetary 2ESSA 4 1/26/67 2Delta-45 TOS-B 1SLC-2E S June 1999 OSO 1 3/7/62 Delta-8 OSO-A (S-16) 17A S 2ESSA 5 4/20/67 2Delta-48 TOS-C 1SLC-2E S OSO 2 2/3/65 Delta-29 OSO-B2 (S-17) 17B S Mission Launch Launch Payload Launch 2ESSA 6 11/10/67 2Delta-54 TOS-D 1SLC-2E S OSO 8/25/65 Delta-33 OSO-C 17B U Name Date Vehicle Code Pad Results 2ESSA 7 8/16/68 2Delta-58 TOS-E 1SLC-2E S OSO 3 3/8/67 Delta-46 OSO-E1 17A S 2ESSA 8 12/15/68 2Delta-62 TOS-F 1SLC-2E S OSO 4 10/18/67 Delta-53 OSO-D 17B S PIONEER (Lunar) 2ESSA 9 2/26/69 2Delta-67 TOS-G 17B S OSO 5 1/22/69 Delta-64 OSO-F 17B S Pioneer 1 10/11/58 Thor-Able-1 –– 17A U Major NASA 2 1 OSO 6/PAC 8/9/69 Delta-72 OSO-G/PAC 17A S Pioneer 2 11/8/58 Thor-Able-2 –– 17A U IMPROVED TIROS OPERATIONAL 2 1 OSO 7/TETR 3 9/29/71 Delta-85 OSO-H/TETR-D 17A S Pioneer 3 12/6/58 Juno II AM-11 –– 5 U 3ITOS 1/OSCAR 5 1/23/70 2Delta-76 1TIROS-M/OSCAR 1SLC-2W S 2 OSO 8 6/21/75 Delta-112 OSO-1 17B S Pioneer 4 3/3/59 Juno II AM-14 –– 5 S 3NOAA 1 12/11/70 2Delta-81 ITOS-A 1SLC-2W S Launches Pioneer 11/26/59 Atlas-Able-1 –– 14 U 3ITOS 10/21/71 2Delta-86 ITOS-B 1SLC-2E U OGO (Orbiting Geophysical
    [Show full text]
  • Photographs Written Historical and Descriptive
    CAPE CANAVERAL AIR FORCE STATION, MISSILE ASSEMBLY HAER FL-8-B BUILDING AE HAER FL-8-B (John F. Kennedy Space Center, Hanger AE) Cape Canaveral Brevard County Florida PHOTOGRAPHS WRITTEN HISTORICAL AND DESCRIPTIVE DATA HISTORIC AMERICAN ENGINEERING RECORD SOUTHEAST REGIONAL OFFICE National Park Service U.S. Department of the Interior 100 Alabama St. NW Atlanta, GA 30303 HISTORIC AMERICAN ENGINEERING RECORD CAPE CANAVERAL AIR FORCE STATION, MISSILE ASSEMBLY BUILDING AE (Hangar AE) HAER NO. FL-8-B Location: Hangar Road, Cape Canaveral Air Force Station (CCAFS), Industrial Area, Brevard County, Florida. USGS Cape Canaveral, Florida, Quadrangle. Universal Transverse Mercator Coordinates: E 540610 N 3151547, Zone 17, NAD 1983. Date of Construction: 1959 Present Owner: National Aeronautics and Space Administration (NASA) Present Use: Home to NASA’s Launch Services Program (LSP) and the Launch Vehicle Data Center (LVDC). The LVDC allows engineers to monitor telemetry data during unmanned rocket launches. Significance: Missile Assembly Building AE, commonly called Hangar AE, is nationally significant as the telemetry station for NASA KSC’s unmanned Expendable Launch Vehicle (ELV) program. Since 1961, the building has been the principal facility for monitoring telemetry communications data during ELV launches and until 1995 it processed scientifically significant ELV satellite payloads. Still in operation, Hangar AE is essential to the continuing mission and success of NASA’s unmanned rocket launch program at KSC. It is eligible for listing on the National Register of Historic Places (NRHP) under Criterion A in the area of Space Exploration as Kennedy Space Center’s (KSC) original Mission Control Center for its program of unmanned launch missions and under Criterion C as a contributing resource in the CCAFS Industrial Area Historic District.
    [Show full text]
  • Apollo Over the Moon: a View from Orbit (Nasa Sp-362)
    chl APOLLO OVER THE MOON: A VIEW FROM ORBIT (NASA SP-362) Chapter 1 - Introduction Harold Masursky, Farouk El-Baz, Frederick J. Doyle, and Leon J. Kosofsky [For a high resolution picture- click here] Objectives [1] Photography of the lunar surface was considered an important goal of the Apollo program by the National Aeronautics and Space Administration. The important objectives of Apollo photography were (1) to gather data pertaining to the topography and specific landmarks along the approach paths to the early Apollo landing sites; (2) to obtain high-resolution photographs of the landing sites and surrounding areas to plan lunar surface exploration, and to provide a basis for extrapolating the concentrated observations at the landing sites to nearby areas; and (3) to obtain photographs suitable for regional studies of the lunar geologic environment and the processes that act upon it. Through study of the photographs and all other arrays of information gathered by the Apollo and earlier lunar programs, we may develop an understanding of the evolution of the lunar crust. In this introductory chapter we describe how the Apollo photographic systems were selected and used; how the photographic mission plans were formulated and conducted; how part of the great mass of data is being analyzed and published; and, finally, we describe some of the scientific results. Historically most lunar atlases have used photointerpretive techniques to discuss the possible origins of the Moon's crust and its surface features. The ideas presented in this volume also rely on photointerpretation. However, many ideas are substantiated or expanded by information obtained from the huge arrays of supporting data gathered by Earth-based and orbital sensors, from experiments deployed on the lunar surface, and from studies made of the returned samples.
    [Show full text]
  • The Moon As a Laboratory for Biological Contamination Research
    The Moon As a Laboratory for Biological Contamina8on Research Jason P. Dworkin1, Daniel P. Glavin1, Mark Lupisella1, David R. Williams1, Gerhard Kminek2, and John D. Rummel3 1NASA Goddard Space Flight Center, Greenbelt, MD 20771, USA 2European Space AgenCy, Noordwijk, The Netherlands 3SETI InsQtute, Mountain View, CA 94043, USA Introduction Catalog of Lunar Artifacts Some Apollo Sites Spacecraft Landing Type Landing Date Latitude, Longitude Ref. The Moon provides a high fidelity test-bed to prepare for the Luna 2 Impact 14 September 1959 29.1 N, 0 E a Ranger 4 Impact 26 April 1962 15.5 S, 130.7 W b The microbial analysis of exploration of Mars, Europa, Enceladus, etc. Ranger 6 Impact 2 February 1964 9.39 N, 21.48 E c the Surveyor 3 camera Ranger 7 Impact 31 July 1964 10.63 S, 20.68 W c returned by Apollo 12 is Much of our knowledge of planetary protection and contamination Ranger 8 Impact 20 February 1965 2.64 N, 24.79 E c flawed. We can do better. Ranger 9 Impact 24 March 1965 12.83 S, 2.39 W c science are based on models, brief and small experiments, or Luna 5 Impact 12 May 1965 31 S, 8 W b measurements in low Earth orbit. Luna 7 Impact 7 October 1965 9 N, 49 W b Luna 8 Impact 6 December 1965 9.1 N, 63.3 W b Experiments on the Moon could be piggybacked on human Luna 9 Soft Landing 3 February 1966 7.13 N, 64.37 W b Surveyor 1 Soft Landing 2 June 1966 2.47 S, 43.34 W c exploration or use the debris from past missions to test and Luna 10 Impact Unknown (1966) Unknown d expand our current understanding to reduce the cost and/or risk Luna 11 Impact Unknown (1966) Unknown d Surveyor 2 Impact 23 September 1966 5.5 N, 12.0 W b of future missions to restricted destinations in the solar system.
    [Show full text]
  • Cost Effects of Destination on Space Mission Cost with Focus on L1, L2
    NASA Cost Symposium, 2018 Export Control Notice Export or re-export of information contained herein may be subject to restrictions and requirements of U.S. export laws and regulations and may require advance authorization from the U.S. Government. Lunar Missions: Earth-orbiting or Planetary? Mitch Lasky, Ball Aerospace Joe Hamaker, PhD, Galorath Federal (With Special Thanks to Mary Ellen Harris, the MSFC REDSTAR Librarian) Contents 2 • Motivation • Purpose • Orbit Descriptions • Earth-orbiting, Lunar, Planetary Mission Characteristics • Parametric Analysis • Historical Cost Analysis • Observations Motivation - Exploration 3 Lunar Exploration Missions 4 Power and Propulsion Element 5 NASA Exploration Campaign 6 Motivation 7 • There is a need to credibly estimate cost of lunar orbital and EM L1, L2 missions – Parametric models typically allow selection of Earth- orbiting or planetary mission ▪ Which results in a more credible cost estimate for lunar missions? This study excludes lunar landers Purpose 8 • This presentation will: – Explore characteristics of Earth-orbiting, lunar orbiting, EM L1, L2, and planetary orbits and what drives spacecraft design and cost – Compare results of parametric cost estimates for spacecraft using Earth-orbiting and planetary input selections – Analyze historical spacecraft cost and mass to determine if there is a statistically valid difference in Earth-orbiting, lunar orbiting, and planetary mission cost – Provide near- and long-term suggestions for lunar orbital and EM L1, L2 cost estimates Orbit Description:
    [Show full text]
  • Feasibility of Characterizing Subsurface Brines on Ceres by Electromagnetic Sounding
    Feasibility of Characterizing Subsurface Brines on Ceres by Electromagnetic Sounding Robert Grimm1, Julie Castillo-Rogez2, Carol Raymond2, Andrew R. Poppe3 1Planetary Science Directorate, Southwest Research Institute, Boulder, Colorado, USA 2Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California, USA 3Space Sciences Laboratory, University of California, Berkeley, California, USA Submitted to Icarus, 28 Sept 2020 Corresponding author: Robert Grimm, [email protected] Abstract Electromagnetic sounding of Ceres is straightforward using the solar wind as a source. The depths to a deep global brine or mud layer and shallow briny intrusions can be assessed simultaneously. 2 1. Introduction Dwarf planet Ceres is the largest object in the main belt and the most water-rich object in the inner solar system (in relative abundance of water to rock). Ceres had sufficient water and silicates (including radioisotopes) to host a deep ocean in its past, leading to a layered interior structure with a high degree of aqueous alteration (Ammannito et al., 2016, Ermakov et al. 2017). The Dawn mission revealed evidence of recent and possibly ongoing geologic activity on Ceres (De Sanctis et al. 2020) and the presence of liquid was inferred below an ice-rich crust (Fu et al. 2017; Scully et al. 2020, Raymond et al. 2020). Recent brine-driven exposure of material onto Ceres’ surface can be found at Occator crater (Nathues et al. 2020) and Ahuna Mons (Ruesch et al. 2016). These multiple lines of evidence for deep liquid and long-lived heat sources call for categorization of Ceres as an ocean world (Castillo-Rogez, 2020). Determination of the depth to liquid water within Ceresspecifically below Occator crateris one objective of a recent Planetary Mission Concept Study (Castillo-Rogez and Brophy, 2020).
    [Show full text]
  • N71-6I7 -Z (ACCESSION NUMBER) 2
    DATA CATALOG SATELLITE EXPERIMENTS SUPPLEMENT NO. 2 TO NSSDC 69-01 OCTOBER 1970 N71-6i7 -Z (ACCESSION NUMBER) 2 ~~7A2<(PA-s 5E (--ASA CR OR TMX OR AD NU BSR) 0CcrR}OR J NATIONAL SPACE SCIENCE LDATA CENTIE GODDARD SPACE FLIGHT CENTER, GRrENDELY, M TIA IONAL AEONATICS AND SPACLE AWMINISTRAIUN by NATIONAL TECHNICAL INFORMATION SERVICE Spnngfild Va 22151 NATIONAL SPACE SCIENCE DATA CENTER SUPPLEMENT TO DATA CATALOG OF SATELLITE EXPERIMENTS (NSSDC 69-01) NSSDC 70-12 OCTOBER 1970 National Aeronautics and Space Administration Goddard Space Flight Center Greenbelt, Maryland 20771 pREOEDING PAGE BLANK NOT FILMED CONTENTS Page Introduction ............................................ ix 63-009A - Explorer 17 ................................... 1 63-009A-03 - Pressure Gauge ........................... 1 63-009A-03A - Neutral Densities (260 km to 900 km) .. 2 64-040C - ERS 13 . ....................................... 2 64-040C-01 - Charged Particle Detectors ............... 2 64-040C-01A - Original Corrected Count Rates on Binary Tape ........................... 3 64-069A - Cosmos 49 ..................................... 3 64-069A-01 - Proton Precessional Magnetometers ........ 4 64-069A-01A - Original Reduced Scalar Field Data on Microfilm ............................. 4 64-069A-01B - Reduced Scalar Field Data on Binary Magnetic Tape ......................... S 64-069A-01C - Reduced Scalar Field Data on BCD Magnetic Tape ......................... 5 64-077A - Mariner 4 ...................................... 6 64-077A-01 - Mars TV Camera ..........................
    [Show full text]
  • Solar Wind Proton Interactions with Lunar Magnetic Anomalies and Regolith
    IRF Scientific Report 306 Solar Wind Proton Interactions with Lunar Magnetic Anomalies and Regolith Charles Lue Swedish Institute of Space Physics, Kiruna Department of Physics, Umeå University, Umeå 2015 ©Charles Lue, December 2015 Printed by Print & Media, Umeå University, Umeå, Sweden ISBN 978-91-982951-0-8 ISSN 0284-1703 Abstract The lunar space environment is shaped by the interaction between the Moon and the solar wind. In the present thesis, we investigate two aspects of this interaction, namely the interaction between solar wind protons and lunar crustal magnetic anomalies, and the interaction between solar wind protons and lunar regolith. We use particle sensors that were carried onboard the Chandrayaan-1 lunar orbiter to analyze solar wind protons that reflect from the Moon, including protons that capture an electron from the lunar regolith and reflect as energetic neutral atoms of hydrogen. We also employ computer simulations and use a hybrid plasma solver to expand on the results from the satellite measurements. The observations from Chandrayaan-1 reveal that the reflection of solar wind protons from magnetic anomalies is a common phenomenon on the Moon, occurring even at relatively small anomalies that have a lateral extent of less than 100 km. At the largest magnetic anomaly cluster (with a diameter of 1000 km), an average of ~10% of the incoming solar wind protons are reflected to space. Our computer simulations show that these reflected proton streams significantly modify the global lunar plasma environment. The reflected protons can enter the lunar wake and impact the lunar nightside surface. They can also reach far upstream of the Moon and disturb the solar wind flow.
    [Show full text]
  • X-616-68-166
    ~~ https://ntrs.nasa.gov/search.jsp?R=19680016260 2020-03-23T22:56:48+00:00Z View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by NASA Technical Reports Server X-616-68-166 LUNAR EXPLORER 35* Norman F. Ness Laboratory for Space Sciences NASA-Goddard Space Flight Center Greenbelt, Maryland USA May 1968 *Presented atXIth COSPAR Tokyo, Japan; 16 May 1968 Extraterrestrial Physics Branch Preprint Series -1- LUNAR EXPLORER 35 Norman F. Ness NASA-Goddard Space Flight Center Greenbelt, Maryland USA --Abstract Lunar Explorer 35, a 104 Kg spin stabilized spacecraft, was placed in lunar orbit on 22 July 1967 with period = 11.5 hours, inclination = 169O, aposelene = 9388 2 100 km, periselene = 2568 +lo0 km, and initial aposelene- 0 moon-sun angle = 304 E. The experiment repertoire includes magnetometers, plasma probes, energetic particle and cosmic dust detectors. Bi-static radar measurements of the electromagnetic properties Qf the lunar surface have been studied by moniCoring the transmitted and reflected RF signal. The spacecraft has operated continuously since launch and has provided new and illuminating data. During its orbit about the earth, the moon is immersed in either interplap-tqry spac~or the geomagnetosheath-geo- magnetotail formed by the solar wind interaction with the earth. In thc geomagnetotail no evidence is found for P 1una.r magnetic field limiting the magnetic moment to lo2') cgs units (less than of the earth). In the interplanetary me Lium no evidenre js foi nd for a bow shock wave due to supersonic solar w.nd flow. The moon docs not accrete interplanetary magnetic field lines 'is theorl'zed by Gold iLnd Tozer, 2nd aS reported from Luna 10 measuremmts.
    [Show full text]
  • Scientific Exploration of the Moon
    Scientific Exploration of the Moon DR FAROUK EL-BAZ Research Director, Center for Earth and Planetary Studies, Smithsonian Institution, Washington, DC, USA The exploration of the Moon has involved a highly successful interdisciplinary approach to solving a number of scientific problems. It has required the interactions of astronomers to classify surface features; cartographers to map interesting areas; geologists to unravel the history of the lunar crust; geochemists to decipher its chemical makeup; geophysicists to establish its structure; physicists to study the environment; and mathematicians to work with engineers on optimizing the delivery to and from the Moon of exploration tools. Although, to date, the harvest of lunar science has not answered all the questions posed, it has already given us a much better understanding of the Moon and its history. Additionally, the lessons learned from this endeavor have been applied successfully to planetary missions. The scientific exploration of the Moon has not ended; it continues to this day and plans are being formulated for future lunar missions. The exploration of the Moon undoubtedly started Moon, and Luna 3 provided the first glimpse of the with the naked eye at the dawn of history,1 when lunar far side. After these significant steps, the mankind hunted in the wilderness and settled the American space program began its contribution to earliest farms. Our knowledge of the Moon took a lunar exploration with the Ranger hard landers' quantum jump when Galileo Galilei trained his from 1964 to 1965. These missions provided us with telescope toward it. Since then, generations of the first close-up views (nearly 0.3 m resolution) of researchers have followed suit utilizing successively the lunar surface by transmitting pictures until just more complex instruments." The most significant before crashing.6 The pictures confirmed that the quantum jump in the knowledge of our only natural lunar dark areas, the maria, were relatively flat and satellite came with the advent of the space age, topographically simple.
    [Show full text]