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(Click for frequent words.) 60 Solar TErrestrial RElations Observatory 59 Saturn Cassini 59 Saturnian moons 59 Relations Observatory STEREO 58 planetary Transits 58 Jovian moons 57 Syrtis Major 57 IBEX spacecraft 57 airglow 57 Jupiter Ganymede 57 Kepler 9c 57 Galilean moons 57 moons orbiting 57 Saturnian moon 57 retrograde orbit 57 ESA Integral 57 thin crescent 57 Europa Ganymede 57 Cloud Aerosol Lidar 57 Convection Rotation 56 constellation Aquarius 56 ray Space Telescope 56 Moderate Resolution Imaging 56 Galileo spacecraft 56 planet Uranus 56 star Spica 56 orbits Saturn 56 moons Phobos 56 Ringed Planet 56 Titan smoggy 56 cosmic cannibal 56 Saturn Enceladus 56 Fermi telescope 56 exosphere 56 HD#b 56 Foton M3 56 gaseous planet 56 constellation Scorpius 56 moons circling 56 Saturn moon 56 comets orbiting 55 Bug Nebula 55 constellation Eridanus 55 Saturnian moon Titan 55 Pluto Charon 55 Orbiter LRO 55 spacecraft Cassini 55 Geminga 55 supergiant star 55 Cancri e 55 moon Enceladus 55 Comet Hartley 2 55 GJ #b [002] 55 Churyumov Gerasimenko 55 Phoebe orbits 55 planet Gliese #g 55 NASA Atmospheric Infrared 55 Venusian atmosphere 55 Corot 7b 55 constellation Andromeda 55 volcanic moon Io 55 Saturn moons 55 THEMIS spacecraft 55 Comet Hartley 55 Fomalhaut b 55 Jovian moon 55 Planck satellite 55 retrograde orbits 55 jovian 54 Eridanus 54 BLG #Lb 54 solar prominences 54 submillimetre wavelengths 54 ESA Cluster 54 retroreflector 54 planets Uranus 54 icy moons 54 Saturn moons Enceladus 54 subsurface ocean 54 Cassini flybys 54 elongated orbits 54 Planetary Transits 54 constellation Hercules 54 Muchachos Observatory 54 Io Europa 54 Galilean satellites 54 Toutatis 54 Samuel Oschin Telescope 54 Infrared Pathfinder Satellite 54 WISE infrared 54 Cassini flyby 54 THEMIS Image 54 Mars moon Phobos 54 smallest exoplanet 54 outer corona 54 comet McNaught 54 Titan Saturn 54 infrared telescopes 54 orbital resonance 54 ecliptic plane 53 ATV Johannes Kepler 53 Comet Churyumov Gerasimenko 53 exoplanetary 53 prograde 53 Jupiter moon Io 53 predawn sky 53 Heterodyne Instrument 53 waning gibbous 53 Trapezium 53 GJ#b 53 superheated gases surrounding 53 constellation Carina 53 Observatory SDO 53 Sagittarius B2 53 WISE spacecraft 53 ESA Huygens probe 53 slender crescent 53 Comet #P/Churyumov-Gerasimenko 53 Martian moons Phobos 53 Crab Pulsar 53 Saturn magnetosphere 53 planets orbits 53 NASA STEREO 53 gamma ray observatory 53 lander rover 53 orbiter Cassini 53 Shepherding Spacecraft 53 extrasolar 53 Cassini Finds 53 Comet Lulin 53 Orbiter MRO 53 mu Arae 53 Upsilon Andromedae 53 solar corona 53 emit X rays 53 Saturnian system 53 constellation Serpens 53 Earth radii 53 Nasa spacecraft 53 Shuttle Docks 53 Launch Scrubbed 53 Kuiper Belt Objects 53 lunar crust 52 Ring Nebula 52 heliopause 52 Cassini Image 52 Olympus Mons 52 Spectroradiometer MODIS 52 Huygens mission 52 periodic dimming 52 COROT 7b 52 Sun synchronous orbit 52 occulted 52 zodiacal light 52 Pleiades cluster 52 Earthlike 52 highly elliptical orbit 52 lunar orbiting spacecraft 52 Pluto Eris 52 planets comets 52 Ulysses spacecraft 52 Zeta Ophiuchi 52 moons Io 52 magnetospheric 52 Kuiper belt objects 52 COROT 52 reentry capsule 52 Saturn moon Mimas 52 photosphere 52 spacecraft orbited 52 Arsia Mons 52 constellation Auriga 52 galactic disk 52 Epsilon Aurigae 52 energetic electrons 52 Skynet 5C 52 Comet Tempel Tuttle 52 Solar Dynamics Observatory 52 moon Io 52 Explorer WISE 52 Sensing Satellite LCROSS 52 absorbs photons 52 ESA Rosetta 52 X ray telescopes 52 Philae lander 52 Upsilon Andromedae b 52 Ontario Lacus 52 Helix Nebula 52 Methone 52 auroral displays 52 Neptune Uranus 52 Comet Holmes 52 rotating neutron stars 52 moon Phobos 52 aurorae 52 AU Mic 52 Imaging Spectroradiometer MODIS instrument 52 LRO LCROSS 52 ESO VLT 52 PSR B# 52 Nasa Mars Odyssey 52 inhabitable planets 52 Huygens lander 52 #/#-ton truss 51 coronagraph 51 Investigation DIXI 51 permanently shadowed craters 51 starlike object 51 geo synchronous 51 Exoplanets 51 Observatory STEREO 51 Spectroradiometer 51 magnetotail 51 polarimetry 51 comet Churyumov Gerasimenko 51 zodiacal dust 51 celestial sphere 51 Charon Pluto 51 lensing galaxy 51 VLTI 51 synchronous orbit 51 WISE telescope 51 Planck telescope 51 HARPS spectrograph attached 51 ESA Planck 51 Capricornus 51 VY Canis Majoris 51 moons Europa 51 smoggy atmosphere 51 Mini Thermal Emission 51 Chajnantor plateau 51 NASA rover Spirit 51 geyser plumes 51 spiral galaxy NGC 51 zodiac constellations 51 MG J# +# 51 constellation Virgo 51 visit http:/saturn.jpl.nasa.gov 51 noctilucent clouds 51 twin Voyager spacecraft 51 Great Orion Nebula 51 Uranus Neptune 51 Neptune Jupiter 51 Mars Pathfinder lander 51 circumstellar disk 51 La Silla observatory 51 accretion disks 51 Galactic cosmic rays 51 composite payload fairing 51 ah dus 51 Cosmic Microwave Background 51 Comet Halley 51 celestial object 51 GJ #b [001] 51 ionizes 51 electron ion 51 Martian lander 51 X ray emitting 51 comet chaser 51 CoRoT #b 51 sized planets orbiting 51 Ocean Salinity 51 Orion constellation 51 Stephan Quintet 51 moon Titan 51 LSAM 51 Curiosity rover 51 comet Lulin 51 Cepheus 51 Kepler 9b 51 XMM Newton satellite 51 galaxy M# [001] 51 Pleiades star 51 helium atoms 51 Vourlidas 51 RHESSI 51 orbiting gamma ray 51 Planck spacecraft 51 Lunar Orbit 51 twin STEREO spacecraft 51 Saturn rings 51 Eridani 51 LORRI 51 Beta Pictoris b 51 lunar equator 51 Infrared Thermal Imaging Spectrometer 51 chromosphere 51 NASA twin STEREO 51 waxing crescent 51 magnetopause 51 Candor Chasma 50 BepiColombo 50 Express orbiter 50 breathing supersonic combustion 50 Epoxi 50 Rosetta orbiter 50 stellar occultations 50 titanium aluminide 50 Uranus Jupiter 50 Lunar Crater 50 MARSIS 50 galaxy NGC 50 circumstellar 50 particle analyzers 50 constellation Cetus 50 Arches Cluster 50 NASA Spacecraft 50 galactic cosmic rays 50 rotational axis 50 radial velocity technique 50 ESA SMART 50 Predator drone flies 50 protoplanet 50 Cygnus Lyra region 50 blue supergiant 50 Beehive Cluster 50 UKIRT 50 Circinus 50 orbital rendezvous 50 Sounder AIRS instrument 50 spinning neutron 50 NASA THEMIS 50 galaxy M# [002] 50 NASA Lunar Prospector 50 ESA XMM Newton 50 zodiacal constellation 50 DISR 50 graphite whiskers 50 lunar highlands 50 Earth magnetotail 50 Epsilon Eridani 50 systems EW suites 50 planets orbiting sun 50 planet magnetosphere 50 HD #b [002] 50 Mount Bosavi 50 NASA Solar Terrestrial 50 heliospheric 50 Orion nebula 50 Mars Uranus 50 planetary surfaces 50 Fermi Telescope 50 comet Tempel Tuttle 50 Jupiter Uranus 50 thin crescent moon 50 cometary debris 50 moon Ganymede 50 Crab Nebula 50 Saturn Uranus 50 Huygens Probe 50 Opportunity Mars rover 50 Fornax cluster 50 Helioseismic 50 interstellar cloud 50 Cassini spacecraft orbiting 50 millisecond pulsars 50 Achernar 50 inner Oort Cloud 50 precessing 50 Fregat upper stage 50 Quaoar 50 Cassini Huygens 50 VIRTIS 50 apogee farthest point 50 Cydonia region 50 Io Europa Ganymede 50 orbital eccentricity 50 constellation Aquila 50 Hubble Space Telescope HST 50 Roque de los 50 millisecond pulsar 50 Climate Sounder 50 Omega Centauri 50 spacecraft Chandrayaan 1 50 Foton spacecraft 50 silicon monoxide 50 Mercury Uranus 50 Sombrero Galaxy 50 arid Kazakh steppe 50 Rosetta spacecraft 50 geysers erupting 50 whiz harmlessly 50 Wolszczan 50 Gliese #e 50 lunar module Eagle 50 Lunar Module Pilot 50 S/# P2 50 exo planet 50 Exoplanet 50 HL Tau 50 blue cloud specked 50 sunlike star 50 Carina constellation 50 TrES 4 50 Jupiter moons Europa 50 gravitational interaction 50 orbited Jupiter 50 mesosphere 50 fainter objects 50 Reiner Gamma 50 TanDEM X 50 Elenin 50 HiRISE camera aboard 50 Puppis 50 Comet #P 50 Oceanus Procellarum 50 comets asteroids 50 moon Dione 50 Atlantis Undocks From 50 ExoMars Trace Gas 50 ESA Mars 50 SN #A 50 mineral olivine 50 NASA Wilkinson Microwave 50 Perseus Cluster 50 silicate dust 50 albedo reflectivity 50 Evolution Explorer 50 Asteroid Belt 50 coronal loops 50 circumstellar disks 50 Veil Nebula 50 occultations 49 Bok globules 49 innermost planet 49 unmanned probes 49 star Proxima Centauri 49 magma ocean 49 Fermi Gamma ray 49 Mars Jupiter Uranus 49 active galactic nucleus 49 planetary transits 49 extrasolar planet 49 ionized gas 49 gravitationally lensed 49 largest moon Charon 49 #P/Churyumov-Gerasimenko 49 NASA Fermi Gamma 49 gamma ray spectrometer 49 moon Mimas 49 Uranian 49 Saturn Uranus Neptune 49 Characterization EPOCh 49 Terra Sirenum 49 sulphate particles 49 Kepler Space Telescope 49 geo synchronous transfer 49 Chandra Observatory 49 barred spiral galaxy 49 George Zamka 49 constellations Cygnus 49 Delta Cephei 49 Mini SAR 49 sodium atoms 49 CALIPSO 49 Heliospheric Observatory 49 KH #D 49 proto cluster 49 Super Earths 49 gravitational perturbations 49 SINFONI 49 Venus Uranus 49 piggybacked Huygens probe 49 earthlike 49 SN #C 49 exoplanets orbiting 49 spherical halo 49 Epsilon Indi 49 imaging spectrometer 49 Gusev crater 49 Spudis 49 ESA GOCE 49 Jupiter magnetosphere 49 waning crescent 49 mysterious uncharted 49 PSR J# 49 neutral mass spectrometer 49 exo planets 49 THEMIS mission 49 heliosheath 49 constellation Leo 49 Lake Vostok 49 STSS Demo 49 Beta Centauri 49 onrushing comet 49 muon neutrino 49 Tempel Tuttle 49 HD# [002] 49 Giovanni Cassini 49 Gliese #c 49 NASA twin rovers 49 OGLE TR #b 49 interplanetary spacecraft 49 gamma ray flares 49 synchronous polar 49 Sagittarius dwarf galaxy 49 galaxies collide 49 OMEGA instrument 49 WMAP satellite 49 Pavonis Mons 49 crystalline silicates 49 permanently shadowed crater 49 aphelion 49 ESA Herschel 49 Descent Imager Spectral Radiometer 49 cosmological distances 49 Kuiper Belt Object 49 Mars orbiting spacecraft 49 moonquakes 49 constellation Lyra 49 Noguchi greeting 49 cosmic ray flux 49 Yarkovsky effect 49 Saturn moon Enceladus 49 Interior Laboratory GRAIL 49 stratospheric balloon 49 polar orbits 49 Ranging spacecraft 49 submillimeter 49 van Arkel discovery 49 Shackleton Crater 49 starburst galaxy 49 Aquarius adore 49 Diviner 49 hydrosphere 49 outermost planets 49 Type Ic supernova 49 geosynchronous satellites 49 Andromeda Galaxy 49 polar craters 49 nebular 49 NuSTAR 49 Anisotropy Probe 49 NGC #A 49 lunar orbits 49 SSMEs 49 Mars CRISM 49 comet tail 49 cumulus cloud 49 penumbral shadow 49 constellation Monoceros 49 spectral fingerprint 49 Nili Fossae 49 submillimeter wavelengths 49 binary quasar 49 1worldspace TM 49 infrared observatory 49 northern arctic plains 49 martian soil 49 arcminutes 49 transiting planet 49 OSTM Jason 2 49 GRB #B 49 Cerro Pachon 49 Earth magnetosphere 49 Deep Impact eXtended Investigation 49 Hubble orbits 49 celestial equator 49 V# Mon 49 waning crescent Moon 49 GQ Lupi 49 Valles Marineris 49 Saturn outermost 49 Aqua satellite 49 entire Milstar constellation 49 coronal mass ejections CMEs 49 Utopia Planitia 49 asterism 49 moon Mab 49 Palaeozoic sedimentary 49 THEMIS satellites 49 SDSS II 49 Kraken Mare 49 HiRISE image 49 masers 49 exoplanets planets 49 Manned missions 48 Tharsis Rise 48 Comet Elenin 48 Comet 9P/Tempel 1 48 Quadrantids 48 protoplanets 48 QQ# 48 extrasolar planet HD #b 48 asteroid Vesta 48 smallest exoplanets 48 Optical Spectroscopic 48 WASP #b 48 STEREO spacecraft 48 nebulae 48 waitress Ingrid Sufan 48 constellation Pisces 48 Betelgeuse 48 THEMIS Images 48 planetary nebulas 48 proto galaxies 48 shadowed craters 48 backscattered 48 pillowy clouds 48 Spectrograph 48 Kuiper belt 48 Voyager spacecraft 48 elliptical orbits 48 IRC +# 48 habitable worlds 48 Lunar CRater Observation 48 six wheeled rover 48 Opportunity parachuted 48 infall 48 polar plateau 48 SIRTF 48 Lulin 48 exoplanet orbiting 48 millimeter wavelength 48 Venus Neptune Uranus 48 robotic rover Spirit 48 Tarantula Nebula 48 Mössbauer 48 NASA rovers Spirit 48 smoothest flattest spot 48 Commander Sergei Volkov 48 MODIS instrument 48 Solar Sail 48 Transiting 48 gamma rays emitted 48 ionise 48 Lunar Reconnaissance Orbiter LRO 48 Dumbbell Nebula 48 lava flowed 48 orbital solitude 48 Keck Interferometer 48 retrorockets 48 Hellas Basin 48 Earthlike planet 48 Virgo Cluster 48 nebulosity 48 comets meteors 48 asteroids Ceres 48 Saturn Jupiter Uranus 48 Martian rovers 48 Yinghuo 1 48 thunderstorms loomed 48 Corot 9b 48 blazar 48 LAGEOS 48 ESO PR 48 planet orbits 48 Jupiter Saturn 48 Mimas 48 P/# A2 48 Kiruna Sweden 48 astrometry 48 supernova SN 48 Horsehead Nebula 48 arcsec 48 Tau Ceti 48 gaseous envelope 48 umbral 48 lunar occultation 48 rotating neutron 48 LCROSS Centaur impact 48 Moon Mineralogy Mapper M3 48 star clusters nebulae 48 Triangulum 48 Libra adore 48 EPOXI 48 Orionids 48 KAGUYA 48 Titan flyby 48 arcseconds 48 martian atmosphere 48 emission nebula 48 Beta Pictoris 48 Oort Cloud 48 constellation Draco 48 Shallow Subsurface Radar 48 Caloris 48 Isidis Planitia 48 Hyades cluster 48 Chilean Atacama Desert 48 ionized particles 48 permanently shadowed regions 48 Multi Object Spectrograph 48 PSLV C# rocket 48 constellation Cassiopeia 48 ionised 48 gamma ray emission 48 evaporite deposits 48 gaseous planets 48 Kuiper Belt object 48 RXTE 48 comet Hale Bopp 48 GALEX 48 Surface Composition Spectrometer 48 Red Rectangle 48 zodiacal constellations 48 constellation Perseus 48 orbiting telescopes 48 Moderate Imaging Spectroradiometer 48 EPOCh 48 MESSENGER MErcury Surface 48 shadowy craters 48 GEochemistry 48 Scorpio adore 48 AIRS instrument 48 ringed planet 48 moonlet 48 perigee nearest point 48 helium nuclei 48 Hot Jupiters 48 SKY WATCH 48 X ray observatory 48 LCROSS spacecraft 48 O OREOS 48 submillimetre 48 twin rover Spirit 48 planets asteroids 48 NASA MErcury Surface 48 Serpens Cauda 48 planet Nibiru 48 Mars Phobos 48 Space ENvironment GEochemistry 48 geosynchronous 48 perihelion 48 ARRL AMSAT 48 twin suns 48 Inuit goddess 48 constellation Bootes 48 SOHO spacecraft 48 red supergiant 48 nicknamed Xena 48 Solar Orbiter 48 CoRoT 9b 48 J# +# [002] 48 orbiting observatories 48 starry heavens 48 dwarf spheroidal 48 detect gamma rays 48 Mpc 48 asteroid Steins 48 carbonaceous chondrite 48 SpaceX Dragon 48 probe Chang'e 48 Martian crater 48 equatorial bulge 48 Georgi Mandushev 48 NASA CloudSat 48 proplyds 48 Nuclear Spectroscopic Telescope Array 48 Reflection Radiometer 48 Globular Cluster 48 Cassini Huygens spacecraft 48 rocky extrasolar planet 48 substorm 48 Corona Australis 48 Mars Orbiter 48 Helios 2B 48 geo synchronous orbit 48 Scutum 48 Enceladus 48 NASA Lunar Reconnaissance 48 micron wavelengths 48 constellation Gemini 47 Huygens descent 47 Martian permafrost 47 SN#A 47 Chajnantor 47 hydroxyl molecules 47 cratered highlands 47 Proxima Centauri 47 SpaceWeather.com 47 Cepheid variables 47 silicate rocks 47 HM Cancri 47 ionised gas 47 Saturn moon Iapetus 47 Kaguya spacecraft 47 shimmering rings 47 fist widths 47 Shackleton crater 47 ejecta curtain created 47 EPOXI spacecraft 47 moons Io Europa Ganymede 47 Solar Terrestrial Relations 47 constellation Centaurus 47 Monoceros 47 waning gibbous moon 47 microquasar 47 Astronomers Discover 47 infrared ultraviolet 47 Jupiter Icy Moons 47 MARSIS instrument 47 icy moon Enceladus 47 moon Europa 47 potassium atoms 47 hexagonal mirrors 47 http:/www.nasa.gov/cassini 47 constellation Taurus 47 Trifid Nebula 47 laser altimeter 47 constellation Ursa Major 47 Fossae 47 Eta Aquarid meteor shower 47 faraway galaxy 47 Astronauts Install 47 Jenniskens 47 lunar landers 47 Flyby 47 magnetic monopoles 47 gimbaled 47 highly collimated 47 Hubble Captures 47 Cat Paw Nebula 47 magnetic dynamo 47 orbiting Kepler telescope 47 Ultraviolet Imaging Spectrograph UVIS 47 ephemeris features 47 comet #P/Churyumov-Gerasimenko 47 Astrophysics MOA 47 Gamma ray bursts GRBs 47 VB #b 47 Cassini orbiter 47 Fireballs lit 47 quantum cascade 47 stellar occultation 47 planetoids 47 cosmic ray particles 47 Martian orbit 47 VIRTIS instrument 47 abyssal plain 47 globular cluster M# 47 Oort cloud 47 Orientale Basin 47 filamentary structure 47 pericentre 47 Martian dust 47 ionized hydrogen 47 NASA Cassini spacecraft 47 Astrological lore 47 Taurids 47 neutron spectrometer 47 preset orbit 47 RRATs 47 Kazakhstan Baikonur Cosmodrome 47 Virgin Galactic unveils 47 Comet Hale Bopp 47 Butterfly Nebula 47 robotic lander 47 icy comets 47 Hanny Voorwerp 47 polar vortex 47 outermost planet 47 Earth Connection Coronal 47 PKS #-# 47 Inc. OTCBB EARH 47 Trifid 47 Habitable Planets 47 gibbous 47 elliptical galaxy NGC 47 Gliese #G 47 Jupiter icy moons 47 Ian McShane Pillars 47 Saturnian 47 HARPS instrument 47 DEM L# 47 telescope eyepiece 47 polar mesospheric clouds 47 Facility SIRTF 47 NASA MESSENGER spacecraft 47 discover Fomalhaut 47 rover Sojourner 47 MErcury Surface Space ENvironment 47 W. Haise 47 EPOXI mission 47 orbiting Saturn 47 Cosmic rays 47 circular orbit 47 Gerard Kuiper 47 spherically symmetric 47 waxing crescent moon 47 equatorial plains 47 Kepler Telescope 47 spacecraft flyby 47 circumstellar dust 47 Magnetic Imager HMI 47 unpolarized 47 SMBHs 47 prominences 47 geo stationary orbit 47 aboard Taurus XL 47 Comet LINEAR 47 Dhanu Rashi 47 Mars Odyssey spacecraft 47 Ocean Salinity SMOS 47 VISTA telescope 47 Crêpes Whaou 47 Comet Encke 47 super perigee moon 47 infalling 47 lunar craters 47 Cerro Paranal 47 hypergolic 47 perigee 47 tholins 47 Comet McNaught 47 Michael Studinger 47 optical wavelengths 47 probe Huygens 47 APXS 47 interstellar dust clouds 47 Permanent Multipurpose Module PMM 47 Martian arctic 47 XMM Newton 47 molten magma 47 Scorpii 47 equatorial latitudes 47 Venus Climate Orbiter 47 planets orbiting distant 47 SN #gy 47 Shuttle Discovery blasts 47 gravitational tides 47 aeroshell 47 emits X rays 47 WISE mapped 47 Zacaton 47 Venusian surface 47 Compact Reconnaissance Imaging Spectrometer 47 midlatitudes 47 Herschel Space Telescope 47 spaceward 47 Lagoon Nebula 47 super Earths 47 extrasolar planets orbiting 47 Viking Lander 47 gravitational tugs 47 High Resolution Imaging 47 Gamma rays 47 Anisotropy Probe WMAP 47 Perseus cluster 47 NEAR Shoemaker 47 shepherding spacecraft 47 IceCube 47 GLAST telescope 47 NASA Cassini 47 Iapetus 47 exobiology 47 sun synchronous orbit 47 sub glacial lakes 47 NFIRE satellite 47 Kepler Mission 47 Proba 2 47 X ray pulses 47 waxing gibbous moon 47 buckypaper virtually 47 outer planets 47 highly magnetized neutron 47 Fermi LAT 47 elongated orbit 47 SGR J# 47 Voorwerp 47 martian surface 47 moon Charon 47 Cabeus crater 47 Camelopardalis 47 Composite Infrared Spectrometer 47 Aurigid 47 Cometary 47 ionized gases 47 Japanese Pressurized Module 46 ultraviolet imaging spectrograph 46 solar radii 46 NASA LCROSS 46 extrasolar planet observations 46 cryovolcanism 46 Main Injector Neutrino 46 volcanically active 46 CoRoT satellite 46 Quadrantid meteor shower 46 entered lunar orbit 46 Delta Aquarids 46 Mission SRTM 46 Terra Meridiani 46 gradiometer 46 Orionid meteors 46 LADEE 46 Terrier Orion 46 Kibo robotic arm 46 Carolyn Porco 46 distant suns 46 Vastitas Borealis 46 lenticular clouds 46 star Gliese 46 Enceladus flybys 46 comets moons 46 cosmic magnifying glass 46 sextile 46 Cryosat 46 rover Spirit landed 46 Deep Impact Extended