The Cambridge guide to the solar system

503 Pages·2011·27.287 MB·English

by  Kenneth R Lang

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TheCambridgeGuidetotheSolarSystem
Richlyillustratedwithfull-colorimages,thisbookisacomprehensive,up-to-datedescrip-
tionoftheplanets,theirmoons,andrecentexoplanetdiscoveries.
Thesecondeditionofthisclassicreferenceisbroughtup-to-datewiththefascinating
new discoveries made during recent years from 12 new solar system missions. Rep-
resentative examples include water on the Moon; widespread volcanism on Mercury’s
previously unseen half; vast buried glaciers on Mars; geysers on Saturn’s active water
moon Enceladus; lakes of methane and ethane on Saturn’s moon Titan; the encounter
withasteroidItokawa;andanencounterandsamplereturnfromcometWild2.Thebook
isfurtherenhancedbyhundredsofstrikingnewimagesoftheplanetsandmoons.
Written at an introductory level appropriate for high-school and undergraduate stu-
dents,itprovidesfreshinsightsthatappealtoanyonewithaninterestinplanetaryscience.
Awebsitehostedbytheauthorcontainsalloftheimagesinthebookwithanoverviewof
theirimportance.Alinktothiscanbefoundatwww.cambridge.org/solarsystem/.
KENNETH R. LANG isaProfessorofAstronomyatTuftsUniversity.Heisawell-known
author and has published 25 books. The Cambridge Encyclopedia of the Sun (Cambridge
University Press, 2001) was recommended by the Library Journal as one of the best
referencebookspublishedthatyear.Hehasextensiveteachingexperience,andhasserved
asaVisitingSeniorScientistatNASAHeadquarters.
SeveralCircles.January–February1926.TheartistVasilyKandinsky(1866–1944)seemstocapturetheessenceofourspace-ageexploration
ofpreviouslyunseenworldsinthiscosmicandharmoniouspainting.AccordingtoKandinsky,“Thecircleisthesynthesisofthegreatest
oppositions.Itcombinestheconcentricandtheeccentricinasingleformandinequilibrium.Ofthethreeprimaryforms,itpointsmost
clearlytothefourthdimension.”(CourtesyoftheSolomonR.GuggenheimMuseum,NewYorkCity,NewYork.)
The Cambridge Guide
to the
Solar System
Second Edition
KennethR.Lang
TuftsUniversity,Medford,Massachusetts,USA
CAMBRIDGE UNIVERSITY PRESS
Cambridge,NewYork,Melbourne,Madrid,CapeTown,
Singapore,Sa˜oPaulo,Delhi,Tokyo,MexicoCity
CambridgeUniversityPress
TheEdinburghBuilding,CambridgeCB28RU,UK
PublishedintheUnitedStatesofAmericabyCambridgeUniversityPress,NewYork
www.cambridge.org
Informationonthistitle:www.cambridge.org/solarsystem
(cid:1)C KennethR.Lang2011
Thispublicationisincopyright.Subjecttostatutoryexception
andtotheprovisionsofrelevantcollectivelicensingagreements,
noreproductionofanypartmaytakeplacewithoutthewritten
permissionofCambridgeUniversityPress.
Firstpublished2003
Secondedition2011
PrintedintheUnitedKingdomattheUniversityPress,Cambridge
AcataloguerecordforthispublicationisavailablefromtheBritishLibrary
ISBN978-0-521-19857-8Hardback
CambridgeUniversityPresshasnoresponsibilityforthepersistenceor
accuracyofURLsforexternalorthird-partyinternetwebsitesreferredto
inthispublication,anddoesnotguaranteethatanycontentonsuch
websitesis,orwillremain,accurateorappropriate.
Contents
Listoffocuselements pageix
Listoftables xi
Prefacetothesecondedition xv
Prefacetothefirstedition xvii
Principalunits xxv
Part1 Changingviewsandfundamentalconcepts
1 Evolvingperspectives:ahistoricalprologue 1
1.1 Movingpointsoflight 3
1.2 Telescopesrevealthehithertounseen 13
1.3 Whatholdsthesolarsystemtogether? 23
1.4 PhysicalpropertiesoftheSun 26
1.5 Terrestrialandgiantplanets 33
1.6 Whatisinsidethemajorplanets? 34
2 Thenewclose-upviewfromspace 36
2.1 Flybys,orbiters,probesandlanders 38
2.2 Impactcraters 52
2.3 Volcanism 60
2.4 Water 71
3 Atmospheres,magnetospheresandthesolarwind 80
3.1 Fundamentals 82
3.2 Atmospheresoftheterrestrialplanets 87
3.3 Atmospheresofthegiantplanets 93
3.4 Titan,asatellitewithasubstantialatmosphere 96
3.5 TheplanetsareinsidetheexpandingSun 98
3.6 Magnetizedplanetsandmagnetospheres 102
3.7 Aurora 111
Part2 Theinnersolarsystem:rockyworlds
4 RestlessEarth:thirdrockfromtheSun 117
4.1 Fundamentals 119
4.2 JourneytothecenteroftheEarth 119
v
vi Contents
4.3 RemodelingtheEarth’ssurface 124
4.4 TheEarth’schangingatmosphere 138
4.5 Spaceweather 151
5 TheEarth’sMoon:steppingstonetotheplanets 158
5.1 Fundamentals 159
5.2 EclipsesoftheMoonandSun 160
5.3 TheMoon’sface 163
5.4 ApolloexpeditionstotheMoon 169
5.5 InsidetheMoon 177
5.6 Thelunarsurface 179
5.7 ReturntotheMoon 186
5.8 TheMoon’shistory 188
5.9 TidesandtheonceandfutureMoon 191
5.10 OriginoftheMoon 196
6 Mercury:adensebatteredworld 201
6.1 Fundamentals 202
6.2 Atinyworldintheglareofsunlight 202
6.3 Space-ageinvestigationsofMercury 203
6.4 RadarprobesofMercury 204
6.5 AmodifiedMoon-likesurface 207
6.6 Anironworld 214
6.7 Amysteriousmagneticfield 215
6.8 EinsteinandMercury’sanomalousorbitalmotion 217
7 Venus:theveiledplanet 220
7.1 Fundamentals 221
7.2 Bright,beautifulVenus 221
7.3 PenetratingthecloudsofVenus 224
7.4 UnveilingVenuswithradar 230
7.5 VolcanicplainsonVenus 235
7.6 HighlandmassifsonVenus 237
7.7 TectonicsonVenus 239
8 Mars:theredplanet 247
8.1 Fundamentals 249
8.2 PlanetMars 250
8.3 Thespace-ageodysseytoMars 252
8.4 Theatmosphere,surfaceconditionsandwindsofMars 253
8.5 ThepolarregionsofMars 259
8.6 HighsandlowsonMars 262
8.7 FlowingwateronMarslongago 266
8.8 Marsisaniceplanet 273
8.9 ThesearchforlifeonMars 276
8.10 ThemysteriousmoonsofMars 280
Contents vii
Part3 Thegiantplanets,theirsatellitesandtheirrings:
worldsofliquid,iceandgas
9 Jupiter:agiantprimitiveplanet 283
9.1 Fundamentals 285
9.2 StormyweatheronJupiter 286
9.3 BeneathJupiter’sclouds 293
9.4 IntroductiontotheGalileansatellites 296
9.5 Jupiter’svolcanicmoonIo 299
9.6 Jupiter’swatermoonEuropa 305
9.7 Jupiter’sbatteredmoons,GanymedeandCallisto 309
9.8 Jupiter’smerewispofaring 311
10 Saturn:lordoftherings 317
10.1 Fundamentals 319
10.2 WindsandcloudsonSaturn 321
10.3 BeneathSaturn’sclouds 324
10.4 TheremarkableringsofSaturn 326
10.5 IntroductiontoSaturn’smoons 335
10.6 Saturn’sactivewatermoonEnceladus 337
10.7 HiddenmethanelakesandorganicdunesonSaturn’smoonTitan 341
10.8 Alienworlds,distantring 345
11 UranusandNeptune 348
11.1 Fundamentals 349
11.2 Stormcloudsontheoutergiants 351
11.3 InteriorsandmagneticfieldsofUranusandNeptune 354
11.4 RingsofUranusandNeptune 355
11.5 ThelargemoonsofUranusandNeptune 358
Part4 Remnantsofcreation:smallworldsinthesolarsystem
12 Asteroidsandmeteorites 365
12.1 Theorbitsofasteroids 367
12.2 Originoftheasteroids 369
12.3 Viewingasteroidsfromadistance 371
12.4 Spacecraftviewasteroidscloseup 375
12.5 Meteorites 381
13 Collidingworlds 391
13.1 AcomethitsJupiter 392
13.2 ConsumedbytheSun 393
13.3 ImpactsofasteroidswiththeEarth 395
13.4 Demiseofthedinosaurs 399
13.5 Assessingtheriskofdeathfromabove 402
13.6 Breakingadatewithdoomsday 403
viii Contents
14 Comets 408
14.1 Unexpectedappearanceofcomets 410
14.2 ThereturnofcometHalley 411
14.3 Wheredocometscomefrom? 413
14.4 Anatomyofacomet 419
14.5 Twocomettails 422
14.6 Spacecraftglimpsethecometnucleus 423
14.7 Rotatingcometnucleus 428
14.8 Cometdecayandmeteorshowers 428
15 BeyondNeptune 435
15.1 Pluto:asmallfrozenworldwithcompanions 436
15.2 Smallcoldworldsintheouterprecinctsoftheplanetarysystem 439
15.3 Edgeofthesolarsystem 442
Part5 Originofthesolarsystemandextrasolarplanets
16 Bravenewworlds 445
16.1 Howthesolarsystemcameintobeing 446
16.2 Newbornstarswithplanet-formingdisks 448
16.3 Thepluralityofworlds 449
16.4 Thefirstdiscoveriesofexoplanets 451
16.5 Hundredsofnewworldscirclingnearbystars 455
16.6 Searchingforhabitableplanets 457
Authorindex 461
Subjectindex 463