The analysis of starlight: two centuries of astronomical spectroscopy

386 Pages·2014·79.225 MB·English

by  Hearnshaw, J. B

TheAnalysisofStarlight
This is the story of the analysis of starlight by astronomical
spectroscopy, spanning from Joseph Fraunhofer’s discovery of
spectrallinesintheearlynineteenthcenturythroughtoaround
theyear2000.Inadditiontothekeydiscoveries, itpresentsthe
culture and social history of stellar astrophysics by introducing
theleadingastronomers, andtheir struggles, triumphs anddis-
agreements. Basic concepts in spectroscopy and spectral anal-
ysis are included, so both observational and theoretical aspects
are described, in a nonmathematical framework. This new edi-
tion covers the final decades of the twentieth century, with its
majoradvancesinstellarastrophysics:thediscoveryofextrasolar
planets,newclassesofstarsandtheobservationoftheultraviolet
spectraofstarsfromsatellites.Thein-depthcoverageofthesub-
ject makesit essential readingfor graduate students workingin
stellarspectroscopy,aswellasamajorreferenceforprofessional
andamateurastronomersandhistoriansofscience.
JOHN B. HEARNSHAW is Professor of Astronomy at the
University of Canterbury, Christchurch, New Zealand. His
research interests span stellar astrophysics, astronomical spec-
trographs and the historical development ofastrophysics. He is
a Fellow of Royal Society of New Zealand, a member of The
InternationalAstronomicalUnionandaForeignAssociateofthe
RoyalAstronomicalSocietyofLondon.ProfessorHearnshawis
theauthoroffourbooksand200papersintheastronomicalliter-
ature,andhasservedaseditorforsevenconferenceproceedings.
He has held visiting positions at Astrophysikalisches
Institut Potsdam, Nagoya University and National University
of Mongolia, Ulaan Baatar. He has also served as Chair of
IAU Program Group for the World-wide Development of
Astronomy, with lecture tours to Mongolia, Cuba, Thailand,
Laos, Vietnam, Mauritius, Trinidad and Tobago, Venezuela,
Paraguay,Uzbekistan,Tajikistan,FijiandNorthKorea.

The Analysis of Starlight:
Two Centuries of
Astronomical Spectroscopy
SecondEdition
John B. Hearnshaw
UniversityofCanterbury,Christchurch,NewZealand
32AvenueoftheAmericas,NewYork,NY10013-2473,USA
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www.cambridge.org
Informationonthistitle:www.cambridge.org/9781107031746
(cid:2)c CambridgeUniversityPress1986,1990
(cid:2)c JohnB.Hearnshaw2014
Thispublicationisincopyright.Subjecttostatutoryexception
andtotheprovisionsofrelevantcollectivelicensingagreements,
noreproductionofanypartmaytakeplacewithoutthewritten
permissionofCambridgeUniversityPress.
Firstpublished1986
Neweditionpublished2014
PrintedintheUnitedStatesofAmerica
AcataloguerecordforthispublicationisavailablefromtheBritishLibrary.
LibraryofCongressCataloguinginPublicationdata
Hearnshaw,J.B.,author.
Theanalysisofstarlight:twocenturiesofastronomicalspectroscopy/JohnB.
Hearnshaw,UniversityofCanterbury,Christchurch,NewZealand.–Secondedition.
pages cm
Includesbibliographicalreferencesandindex.
ISBN978-1-107-03174-6(hardback)
1. Astronomicalspectroscopy–History. I. Title.
QB465.H43 2014
(cid:3)
522.6709–dc23 2013030427
ISBN978-1-107-03174-6Hardback
CambridgeUniversityPresshasnoresponsibilityforthepersistenceoraccuracyof
URLsforexternalorthird-partyInternetWebsitesreferredtointhispublication
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Contents
Prefacetothesecondedition xi
Prefacetothefirstedition,1986 xiii
Acknowledgements xv
Acknowledgementsforthesecondedition xv
Acknowledgementsforthefirstedition(1986) xv
1 Introductiontospectroscopy,spectroscopesandspectrographs 1
1.1 Introduction 1
1.2 Basicconceptsinspectroscopy 1
1.2.1 Terminology 1
1.2.2 Wavelengthandcolour 2
1.2.3 Continuous,emissionandabsorptionspectra 2
1.2.4 Resolutionandresolvingpowerofspectroscopes 3
1.3 Thedevelopmentofthespectrographandspectroscopedesign 3
1.3.1 Prisminstrumentsinthenineteenthandearlytwentiethcenturies 3
1.3.2 Earlyobjectiveprisminstruments 5
1.3.3 Earlygratingspectroscopesandspectrographs 5
1.3.4 Thedevelopmentofcoudéspectrographs 6
1.3.5 Thedevelopmentoftheéchellespectrograph 9
1.3.6 TheCCDasadetectorforastronomicalspectroscopy 11
2 Theanalysisofsunlight:theearliestpioneers 15
2.1 IsaacNewtonandthecompositionofsunlight 15
2.2 Invisibleraysinthesolarspectrum:ThomasYoungandthemeasurementofwavelength 16
2.3 WilliamWollastonandthediscoveryofthesolarlinespectrum 16
2.4 JosephFraunhoferandthesolarlinespectrum 17
2.5 PlanetaryandstellarspectraobservedbyFraunhofer 19
3 Thefoundationsofspectralanalysis:fromFraunhofertoKirchhoff 21
3.1 Thebeginningsofspectralanalysis:theworkofSirJohnHerschel 21
3.2 SirDavidBrewsterandspectralanalysis 21
3.3 FoxTalbotandthespectraofflames 22
3.4 FurtherprogressinstudyingthesolarinfraredbyJ.Herschel,FizeauandFoucault 22
3.5 EdmondBecquerelandsolarspectrumphotography 23
3.6 ThephotographicsolarspectrumofJ.W.Draper 24
3.7 SirGeorgeStokesandthefluorescentultravioletsolarspectrum 25
3.8 Therelationshipbetweenheat,lightand‘chemicalrays’ 25
3.9 TheoriginoftheFraunhoferlines 26
3.10 AkeyobservationbyFoucaultasasteptowardsunderstandingtheFraunhoferspectrum 27
3.11 KirchhoffannouncesthepresenceofsodiumintheSun 27
v
vi Contents
3.12 Theemissionandabsorptionofradiation:thetheoreticalworkofBalfourStewartandKirchhoff 28
3.13 Furtherlaboratoryworkintheanalysisofflame,arcandsparkspectra 28
3.14 BunsenandKirchhoff:chemicalanalysisofthesolarspectrum 28
3.15 ReactionstotheworkofKirchhoffandBunsen 29
4 Earlypioneersinstellarspectroscopy 33
4.1 Stellarspectroscopybefore1860 33
4.2 Stellarspectroscopy:anewbeginning 33
4.3 LewisRutherfurd 35
4.4 EarlyspectroscopyatGreenwich 35
4.5 AngeloSecchiandspectralclassification 36
4.6 WilliamHugginsandstellarcomposition 41
4.7 WolfandRayetandtheiremission-linestars 44
4.8 Huggins’laterwork:cometsandtheDopplereffect 44
4.9 HenryDraper,WmHugginsandspectrumphotography 45
4.10 HermannCarlVogel 47
4.11 Thediscoveryofhelium 50
4.12 Vogel’ssecondclassification 52
4.13 Vogelandphotographicradial-velocitydeterminations 52
4.14 NormanLockyerandthemeteoritichypothesis 53
4.15 Newsouthernemission-linestars:Herschel,Ellery,Pechüle,Copeland 56
4.16 Thespectraofredstars:d’Arrest,Dunér,Espin 57
4.17 NicholasvonKonkoly,EugenvonGothardandthefirstsupernovaspectrum 58
4.18 Spectrumphotographyinthe1890s:McClean,Scheiner,Sidgreaves 59
5 SpectralclassificationatHarvard 63
5.1 EdwardPickeringatHarvardCollegeObservatory 63
5.2 MrsDraperandtheHenryDraperMemorial 63
5.3 WilliaminaFlemingandtheDraperMemorialCatalogue 64
5.4 EstablishmentoftheBoydenStationatArequipa,Peru 66
5.5 TheMauryclassification 66
5.6 AntoniaMaury’s‘collateraldivisions’basedonlinewidth 68
5.7 IonizedheliumlinesandthePickeringseries 70
5.8 AnnieCannonandtheHarvardclassificationof1901 71
5.9 AnnieCannon’sclassificationsof1912 73
5.10 The1910meetingoftheInternationalSolarUnionandthespectralclassificationquestionnaire 74
5.11 WilliaminaFleming’sworkonstarswithpeculiarspectra 75
5.12 Emission-linestarscataloguedbyAnnieCannon 78
5.13 TheHenryDraperCatalogue:programmeinitiatedbyPickeringandCannon 78
5.14 PublicationoftheHDCatalogue 79
5.15 TheHenryDraperExtension 82
5.16 StatisticalanalysisoftheHDdata:Shapleyandgalacticstructure 83
6 TheDopplereffect 86
6.1 EarlyhistoryoftheDopplereffect 86
6.2 FizeauandMachandtheconceptoflinedisplacements 86
6.3 FirstattemptstoobserveDopplershiftsbySecchiandHuggins 87
6.4 VisualDopplershiftprogrammesofMaunderandChristie(Greenwich)andSeabroke(Rugby) 88
6.5 TheDopplereffectandsolarrotation 89
6.6 Visualradial-velocitymeasurementsbyKeeleratLick 89
6.7 Photographicradial-velocityworkbyVogelandScheineratPotsdam 90
Contents vii
6.8 Radial-velocityworkofBelopolskyatPulkova 91
6.9 Radial-velocityprogrammesintheUnitedStates,FranceandBritaininthe1890s 92
6.10 WilliamW.Campbell 94
6.11 TheD.O.MillsexpeditiontoChile 95
6.12 Campbell,WrightandMooreatLick 97
6.13 Campbell’sanalysisofsolarmotion 99
6.14 Newradial-velocityprogrammesestablishedearlyinthetwentiethcentury 99
6.15 TheMtWilsonradial-velocityprogramme 100
6.16 High-velocitystarsandthediscoveryofgalacticrotation 100
6.17 JohnPlaskettattheDominionAstrophysicalObservatory,Victoria 101
6.18 EdwinFrostatYerkesObservatory 102
6.19 Cepheidvariablesandthepulsationtheory 104
6.20 TheInternationalAstronomicalUnionandradial-velocityprogrammes 106
6.21 Standardwavelengthsandstandardstars 106
6.22 Radial-velocitycatalogues 107
6.23 Radial-velocityprogrammesinthe1930s:DavidDunlapandMcDonaldobservatories 108
6.24 Radial-velocityworkintheSovietUnionandinthesouthernhemisphere,1930–1950 108
6.25 TheWilsonGeneralCatalogue 109
6.26 Changingtrendsinradial-velocityresearchfromthe1950s 110
6.27 EmpiricalconfirmationofDopplerandgravitationalshifts 111
6.28 Objectiveprismradialvelocities 111
6.29 Photoelectricradialvelocities 114
6.30 Newradial-velocitycataloguesofthelatetwentiethcentury 116
6.31 Stellarrotation 116
6.32 Rotationinbinarystars 117
6.33 Rotationinsinglestarsandthecorrelationwithspectraltype 118
6.34 Thediscoveryofextrasolarplanets 120
7 Theinterpretationofstellarspectraandthebirthofastrophysics 127
7.1 Someearlytheoriesofstellarevolution 127
7.2 Hertzsprung’sanalysisoftheMauryc-typestars 127
7.3 Monck’sanalysisofpropermotionandluminosity 129
7.4 Russell’sworkonluminosityandspectraltype,andhisrelationshipto
Hertzsprung 129
7.5 AdamsandKohlschütter’sworkonluminosityeffectsinstellarspectra 132
7.6 Newdevelopmentsinatomicphysicsandtheirinfluenceonastrophysics 133
7.7 ThefirststellartemperaturesmeasuredbyWilsingandScheiner 133
7.8 Photographicallydeterminedstellarenergydistributions 134
7.9 FurthervisualspectrophotometryatPotsdam 135
7.10 Sahaandthetheoryofionization 135
7.11 Saha’sanalysisofthesequenceofHarvardspectraltypes 136
7.12 FowlerandMilneandthemethodoflinestrengthmaxima 137
7.13 Ionizationtheoryandluminosityeffectsinstellarspectra 138
7.14 CeciliaPayneandtheempiricalconfirmationofionizationtheory 138
7.15 TheRussell–Adams–Mooreanalysisofthesolarspectrum 140
7.16 RussellandAdamsonstellarcomposition 140
7.17 UnsöldandRussellonthecompositionoftheSun 141
7.18 Thefirstcurveofgrowth 142
7.19 Thecurveofgrowthappliedtointerstellarandstellarlines 144
7.20 Thegradienteffectandstellaratmosphericturbulence 146
viii Contents
7.21 SubsequentworkinsolarspectralanalysisandtheUtrechtSolarAtlas 148
7.22 KennethWrightandthesolarcurveofgrowth 149
8 Spectralclassification:FromtheHenryDraperCataloguetotheMKsystemandbeyond 152
8.1 ThefirstInternationalAstronomicalUnionmeetinginRome,May1922 152
8.2 TheclassificationofOstars 153
8.3 Spectralclassificationofnebulae 155
8.4 ThespectroscopyofnormalBstars 158
8.4.1 Linestrengths,spectraltypesandthesinglet-tripletanomaly 158
8.4.2 TheStarkeffect,luminositycriteriaandspectroscopicparallaxes 160
8.5 Spectralclassificationprogrammesinthe1920sand1930s 162
8.6 BertilLindbladandthespectrophotometryoflate-typestars 165
8.7 Barbier,ChalongeandtheBalmerjump 165
8.8 TotheMKKclassificationandbeyond 168
8.8.1 TheoriginsoftheMKKtwo-dimensionalclassification 168
8.8.2 TheMKKAtlasofStellarSpectra 170
8.8.3 SomecommentariesontheMKKsystem 170
8.8.4 SpectralclassificationatYerkesaftertheMKK 171
8.8.5 TheMKsystem 173
8.9 Theclassificationofthecarbonstars 173
8.9.1 Introductionandsummaryofprincipalbandsystems 173
8.9.2 ClassificationofcarbonstarsaftertheHDCatalogue 175
8.9.3 Otherproposedcarbonstarclassifications 177
8.9.4 CarbonisotoperatiosandtheJ-typestars 178
8.9.5 Carbonstarcatalogues 179
8.10 TheclassificationandspectraofSstars 179
8.10.1 Sstars,1922–1970 179
8.10.2 AnewunderstandingoftheSspectraltype,from1970 182
8.11 VanadiumoxideandmetallichydridesintheM-typestars 182
8.12 Spectralclassification1970–2000 184
8.13 ThediscoveryofbrowndwarfsandtheintroductionoftheLandT
spectraltypes 185
8.13.1 Thediscoveryofbrowndwarfs 185
8.13.2 Thelithiumtestforbrowndwarfs 185
8.13.3 NewspectralclassesLandT 186
9 Spectroscopyofpeculiarstars 193
9.1 Introductiontopeculiarstars 193
9.2 CarlyleBealsandtheWolf–Rayetclassification 193
9.3 Spectralclassificationofnovae 196
9.3.1 NovaspectralclassificationbyWilliams 199
9.4 EmissionlineBstars:theBestars 201
9.4.1 HerbigAeandBestars 204
9.5 ThepeculiarA-typestars:anastrophysicalenigma 205
9.5.1 DiscoveryofpeculiarAstarsandearlyprogressupto1930 205
9.5.2 W.W.MorganandApstars,1931–1935 206
9.5.3 HoraceBabcockandmagneticfieldsintheApstars 207
9.5.4 Theobliquerotatormodelformagneticstars 208
9.5.5 SpectralclassificationofApstars 209
9.5.6 Themanganesestarsandotherearly-typepeculiarstars 209
9.5.7 Chemicallypeculiarstars 210