1ASTR 1040 ASTR 1040 AccelAccelAstroAstro::Stars & GalaxiesStars & GalaxiesProf. Prof. JuriJuriToomreToomreTA: Nicholas NelsonTA: Nicholas NelsonLecture 17 Tues 8 Mar 2011Lecture 17 Tues 8 Mar 2011zeus.colorado.edu/astr1040zeus.colorado.edu/astr1040--toomretoomreBinary Binary massmasstransfertransferToday Today ••Joys of nearest supernova: Joys of nearest supernova: SN 1987ASN 1987A••How How mass transfer from binary companionmass transfer from binary companioncan can spinspin--upuppulsarpulsar••White dwarf supernovae White dwarf supernovae from mass transfer in from mass transfer in binary system, but also repeated binary system, but also repeated novaenovae••Remarkable Remarkable whitewhite--dwarf supernovae dwarf supernovae (binaries)(binaries)LogisticsLogistics••Evening Review on Evening Review on ThurThur77--9 pm for 9 pm for Second MidSecond Mid--Term ExamTerm Examon Mon Mar 14 on Mon Mar 14 ••Review Sheet #2Review Sheet #2and new Homework Set # 8 and new Homework Set # 8 available. HW # 7 due today available. HW # 7 due today ••Observatory Night # 5 tonight, 7pm+.Observatory Night # 5 tonight, 7pm+.••Overview read Overview read S.3 S.3 SpacetimeSpacetime& Gravity& Gravity••Read Read Chap 19Chap 19Our Galaxy Our Galaxy with carewith care••Remember:Remember:Planet FinderPlanet Finderhomework due next homework due next ThurThurMar 17 (prior SB)Mar 17 (prior SB)Pulsars and Neutron StarsPulsars and Neutron StarsPulsars are lighthouses Pulsars are lighthouses in our Galaxy!in our Galaxy!REMINDERREMINDERSynchrotron RadiationSynchrotron Radiation••Fast electrons in Fast electrons in strong magnetic strong magnetic fieldsfieldsneutron neutron stars, black holesstars, black holes••Different shapeDifferent shapefrom thermal from thermal radiation: radiation: emits at emits at all wavelengths,all wavelengths,strongest in radiostrongest in radioVisible vs. XVisible vs. X--ray emissionray emission••Thermal lightThermal lightfrom from starsstarsvisible and IRvisible and IR••Synchrotron lightSynchrotron lightfrom from neutron neutron starsstarsXX--ray ray and radioand radioVisible lightVisible lightXX--ray lightray light2Visible Light vs. RadioVisible Light vs. RadioThermal vs. SynchrotronThermal vs. SynchrotronElliptical galaxy Elliptical galaxy ----visiblevisibleSame galaxy Same galaxy ----radioradioSN: SN: CrabCrabNebulaNebulaM1M14 July 10544 July 1054Back toBack tofamousfamousfriend !friend !CrabCrab’’s pulses pulsepatternspatternsxx--rayrayvisiblevisibleradioradioCrabCrabNebulaNebulaSNRSNRinfraredinfraredradioradioopticalopticalxx--rayrayCrab SNRCrab SNRcompositecompositeOct 06:Oct 06:Spitzer (IR), Spitzer (IR), Chandra (X), Chandra (X), Hubble (V)Hubble (V)ChandraChandraXX--ray viewray viewof Crabof Crabcentercenter3Crab pulsar at work: Nov 00 Crab pulsar at work: Nov 00 ––Apr 01Apr 01Chandra XChandra X--rayrayHST VisibleHST VisibleGradual slowing Gradual slowing down of down of pulsar rotationpulsar rotationEnergy emittedEnergy emittedin pulses comesin pulses comesfrom from rotationalrotationalkinetic energykinetic energyListening Listening to Pulsarsto Pulsars••PSR PSR B0329+54B0329+54typical, normal pulsartypical, normal pulsar: period : period 0.714 sec (~0.714 sec (~1.401.40rotations/sec)rotations/sec)••PSR PSR B0933B0933--45 45 VELAVELApulsar: period 89 pulsar: period 89 millisecmillisec(0.089 sec) (~(0.089 sec) (~1111rot/sec) in SNR ~10,000 yrs agorot/sec) in SNR ~10,000 yrs ago••PSR PSR B0531+21 B0531+21 CRABCRABpulsar: ~pulsar: ~3030rot/sec rot/sec youngest knownyoungest known••PSR PSR J0437J0437--47154715““millisecmillisec””pulsar, ~pulsar, ~174174rot/secrot/sec••PSR PSR B1937+21B1937+21fastestfastestpulsar, ~pulsar, ~642642rot/sec rot/sec surface of star moving at 1/7 c!surface of star moving at 1/7 c!REVISITREVISITClicker review Clicker review ––red giantsred giants••The The main source of energymain source of energyfor a star as it for a star as it grows in size to become a grows in size to become a red giantred giantis is _______ ._______ .••A.A.gravitational contractiongravitational contraction••B.B.hydrogen fusion in a shell around corehydrogen fusion in a shell around core••C.C.helium fusion in the corehelium fusion in the core••D.D.hydrogen fusion in the corehydrogen fusion in the coreB.B.Large Large MagellanicMagellanicCloud (LMC)Cloud (LMC)(10,000 tiles (10,000 tiles with Spitzer with Spitzer composite IR)composite IR)Story ofStory ofSN 1987ASN 1987Ain LMCin LMC24 Feb 1987: SN in LMC24 Feb 1987: SN in LMC(160,000 (160,000 lylyaway)away)BEFOREBEFOREAFTER AFTER (SN 1987A)(SN 1987A)4Mysterious triple rings in SN 1987AMysterious triple rings in SN 1987A20 year birthday picture (Chandra + HST)20 year birthday picture (Chandra + HST)Supernova SN 1987ASupernova SN 1987ASN 1987A: Brightening knots SN 1987A: Brightening knots 1994 > 20061994 > 2006Making a Making a millisecondmillisecondpulsars pulsars ––spin it up!spin it up!••Mass transfer onto Mass transfer onto neutron starneutron starin binary in binary system can system can spin upspin upthe the pulsar pulsar ––even to 1000 even to 1000 times per second (ms)times per second (ms)••Accretion disk formsAccretion disk forms::extremely hot ( extremely hot ( ““XX--ray ray BursterBurster””if He fusion)if He fusion)““Black WidowBlack Widow””millisecond pulsar millisecond pulsar ––evaporating companion star in cocoon has spun it upevaporating companion star in cocoon has spun it upChandra XChandra X--ray Imageray ImageSketchSketchSNRSNR““numbers gamenumbers game””CygnusCygnusLoopLoop5Cassiopeia A: SN in ~1680 (Cassiopeia A: SN in ~1680 (FlamsteedFlamsteed))YoungestYoungestSNR in MWSNR in MW(Chandra (Chandra XX--ray image)ray image)synchrotronsynchrotronemissionemissionNeutronNeutronstar atstar atcentercenterCass A: Viewed with Spitzer IRCass A: Viewed with Spitzer IRKeplerKepler’’ssSNR (1604)SNR (1604)ChandraChandraXX--ray imageray imagered:red:oxygenoxygenyellow:yellow:ironironblue:blue:shockshock““promptprompt””Type Type IaIaSNSNTemperatureTemperature1010661010--4440,00040,0003,0003,000““Stellar graveyardStellar graveyard””is very much alive !is very much alive !Mass transferMass transferininbinaries adds jazzbinaries adds jazz……LLwhite dwarfs,white dwarfs,neutron starsneutron starsor black