OverviewThisonlinelessonsconsistsofthechaptersTheSolarSystemThePlanetsMoonsPlanetsofotherstarsMoreinformation:Links第一頁(yè)第二頁(yè)，共24頁(yè)。TheSolarSystemWhatistheSolarSystem?IntheUniverse,

theSolarSystemisourhomeland,

andtheEarthisourhometown.第二頁(yè)第三頁(yè)，共24頁(yè)。TheSolarSystemTheSolarSystemconsistsof

thesuninitscentrenineplanets,

circlingaroundthesunmoonsasteroidsandcomets.第三頁(yè)第四頁(yè)，共24頁(yè)。TheSolarSystemHowdidtheSolarSystemevolve?Scientistsarequitesure,thatinthebeginningofourSolarSystemtherewasahugediscofdirt,rocks,gas,iceetc.Inthemiddleofthisdisc,theSunformeditselfandbegantoglow.Insomedistancesfromthecentre,theplanetsemergedfromtheseringsofdirt,rocksandgas.第四頁(yè)第五頁(yè)，共24頁(yè)。TheSolarSystemHowlargeisourSolarSystem?TheorbitonwhichPluto(thefarthestplanet)circlesthesun,hasanaveragediameterof5.910.000.000km(Pluto‘sorbitisrathernon-circular).Thesunitself,thelargestobjectinourSolarSystemhasadiameterof1.392.520km.第五頁(yè)第六頁(yè)，共24頁(yè)。TheSolarSystemHowcanIimaginethesesizesanddistances?ImaginetheSolarSystembeingasoccerground(about100mlong).Thesunwouldbeaglaringorangeinthecentre.Plutowouldencirclethesunattheedgeofthesoccerground,havingthesizeofadustparticle.TheEarthwouldbe1,30mawayfromthe“orange“,havingthesizeofasesameseed.第六頁(yè)第七頁(yè)，共24頁(yè)。TheSolarSystem第七頁(yè)第八頁(yè)，共24頁(yè)。ThePlanetsMercuryistheplanetthatisclosesttoourSun.Plutoisthefarthest.Remembertheorderoftheplanetslikethis:MyVeryEducatedMotherJustShowedUsNinePlanets whichmeansMercuryVenusEarthMarsJupiterSaturnUranusNeptunPluto第八頁(yè)第九頁(yè)，共24頁(yè)。MercuryWhatareMercury‘sfeatures?secondsmallestplanetnearesttothesunoneMercury-yearisaquarterEarth-yearMercuryisverydifficulttobespottedwiththenakedeyeMercuryhasnomoons第九頁(yè)第十頁(yè)，共24頁(yè)。VenusWhatareVenus‘features?itisamediumsizedplanet,2.5timesaslargeasMercurysecondnearesttothesunVenusisverywellvisibletothenakedeye,alwaysclosetothesunbeforesunriseoraftersunsetVenushasnomoons第十頁(yè)第十一頁(yè)，共24頁(yè)。EarthWhatareEarth‘sfeatures?itisamediumsizedplanet,abitlargerthanVenus(probably)theonlyplanetwithliquidwaterinourSolarSystemtheEarthhasonemoon(probably)theonlyplanetwithintelligentlifeinourSolarSystem第十一頁(yè)第十二頁(yè)，共24頁(yè)。MarsWhatareMars‘features?itisasmallsizedplanet,halfaslargeasEarthMarsiswellvisibletothenakedeyeMarshastwomoons:PhobosandDeimosMarshasbeenvisitedbyroboticvehicles:

Pathfinder,SpiritandOpportunitythequestionfor(former)lifeonMarsisstillunsolved第十二頁(yè)第十三頁(yè)，共24頁(yè)。JupiterWhatareJupiter‘sfeatures?itisthelargestplanetoftheSolarSystem,

morethan1.300EarthscouldfitinsideJupiteriswellvisibletothenakedeyeTheGreatRedSpotonitssurfaceisagiantstormaswideasthreeEarthsJupiterhas63moons!(thelargestareIo,Callisto,GanymedeandEuropa)第十三頁(yè)第十四頁(yè)，共24頁(yè)。SaturnWhatareSaturn‘sfeatures?itisthesecond-largestplanetoftheSolarSystem,onlyabitsmallerthanJupiterSaturniswellvisibletothenakedeyethefamousringscanbeseenwithsmalltelescopesSaturnhasatleast34moons!(recentlyaprobelandedonJupiter‘smoonTitan)第十四頁(yè)第十五頁(yè)，共24頁(yè)。UranusWhatareUranus‘features?itismediumsizedplanetoftheSolarSystemitisquitefarawaybutstillcanbespottedwithsmalltelescopeslikeSaturn,UranushasasystemofringsSaturnhasatleast27moons第十五頁(yè)第十六頁(yè)，共24頁(yè)。NeptuneWhatareNeptune‘sfeatures?itismediumsizedplanetoftheSolarSystem,onlyalittlebitsmallerthanUranusitisquitefarawaybutstillcanbespottedwithsmalltelescopesNeptunehasfourringsandatleast13moons第十六頁(yè)第十七頁(yè)，共24頁(yè)。PlutoWhatarePluto‘sfeatures?itisthesmallestplanetofourSolarSystemSincePlutoisfarawayandsosmall,youneedamedium-sizedprofessionaltelescopeoragoodamateurtelescopetospotit.NooneknowswhatPlutolookslike–it‘stoofarawayandtoosmall.Thepictureinthebackgroundisanartist‘srendition.Plutohasonemoon:Charon第十七頁(yè)第十八頁(yè)，共24頁(yè)。MoonsWhataremoons?Moonsarelikelittleplanetsthatencircletherealplanets.Usually,theyaremuchsmallerthanplanets.Planetscanhavenomoons(likeMercuryandVenus),onemoon(likeEarth)oruptoaverylargenumberofmoons(e.g.63forJupiter).第十八頁(yè)第十九頁(yè)，共24頁(yè)。MoonsPhobosandDeimosPhobosandDeimosareMars‘companions.Phobosmeans“fear“,Deimosmeans“panic“.MarsitselfhasbeennamedfortheRomanGodofWar.Theyarequitesmall(<15km)andlookratherlikepotatoesthanlikemoons.第十九頁(yè)第二十頁(yè)，共24頁(yè)。MoonsIo,Callisto,GanymedandEuropaThesefourmoonsarethebiggestmoonsofJupiter.Theycanbeseenwithsmalltelescopesorevenwithbinoculars.EuropaIo第二十頁(yè)第二十一頁(yè)，共24頁(yè)。PlanetsofotherstarsAretheremoreplanetsintheUniverse(exceptfortheonesintheSolarSystem)?Yes,thereareotherplanets,so-calledextra-solarplanets.

Butitisverydifficulttospotthem,sincetheyarefarfaraway.第二十一頁(yè)第二十二頁(yè)，共24頁(yè)。PlanetsofotherstarsHowcanplanetsofotherstarsbespotted?Therearetwomainwaysthatastronomerssearchfortheseplanets:Ifyouobserveastarveryaccuratelywithspecialinstruments,youmay