Slide 1Slide 2Slide 3Slide 4Slide 5Slide 6Slide 7Slide 8Slide 9SupernovaHST Image of Supernova 1994D in NGC 4526SupernovaPossible petrographs: 1054 Supernova (now Crab Nebula) in Chaco Canyon. Photo by Ron LussierSupernovaA 1,000-year-old petroglyph may depict the biggest, brightest supernova ever seen by humans, one astronomer says.SupernovaSupernova is an exceptionally violent explosion of a star.In a supernova event, a star will rapidly increase its luminosity to roughly 109 solar luminosities.In the Milky Way galaxy, supernova events happen about once every 30 years.Most occur behind a layer of dust in the galaxy, and cannot be seenThe supernova of 1006 was recorded by the Chinese. The event reached a maximum of about 1/10 as bright as the full moon.SupernovaPowerful sources of radio and X-ray emissions.Appear somewhere in the sky at a rate of about 1 per second.Occur in two types – Type I and Type II SupernovaUnfortunately, do not know where they will occur.Historical SupernovaeHistorical SupernovaeDate (AD)Date (AD)TypeTypeMagnitude at MaxMagnitude at MaxDiscovered byDiscovered byRemnantRemnant185185I (?)I (?)-8-8ChineseChineseRCW86RCW86393393??-1-1ChineseChinese837 (?)837 (?)??-8 (?)-8 (?)ChineseChineseIC 443IC 44310061006II-10-10Chinese/ArabsChinese/ArabsSN1006SN100610541054IIII-5-5China/Japan/China/Japan/Chaco CanyonChaco CanyonCrab NebulaCrab Nebula11811181??-1-1China/JapanChina/Japan3C583C5815721572II-4-4Tycho BraheTycho BraheTychoTycho16041604II-3-3KeplerKeplerKeplerKepler16801680IIII5 (?)5 (?)FlamsteedFlamsteedCas ACas A19871987IIII2.92.9Ian SheltonIan SheltonSN1987ASN1987ASupernovaSupernovaTWO VERY DIFFERENT TYPES OF SUPERNOVAETWO VERY DIFFERENT TYPES OF SUPERNOVAESupernova TypeSupernova TypeType Ia*Type Ia*Type IIType IIMaximum LuminosityMaximum Luminosity3 x 103 x 1099 Suns (M Suns (MBB = -19.5) = -19.5)3 x 103 x 1088 Suns (M Suns (MBB = -18.5 +/- 1) = -18.5 +/- 1)SpectrumSpectrumNo hydrogen linesNo hydrogen linesLines of many heavy elementsLines of many heavy elementsHydrogen linesHydrogen linesContinuumContinuumWhere foundWhere foundAmong old star systemsAmong old star systems(galactic bulge, elliptical (galactic bulge, elliptical galaxies)galaxies)Among young star systemsAmong young star systems(star-forming regions in disk (star-forming regions in disk galaxies)galaxies)Parent StarParent StarWhite dwarf in binary systemWhite dwarf in binary systemMassive star (usually a red Massive star (usually a red supergiant)supergiant)Trigger mechanismTrigger mechanismMass transfer from companionMass transfer from companionCollapse of iron coreCollapse of iron coreExplosion mechanismExplosion mechanismThermonuclear explosion of Thermonuclear explosion of carbon/oxygen core --> ironcarbon/oxygen core --> ironRebound shock from neutron Rebound shock from neutron star surface: neutrino pressurestar surface: neutrino pressureLeft behindLeft behindNothingNothingNeutron starNeutron starDebrisDebrisMostly ironMostly ironAll kinds of elementsAll kinds of elements*Types Ib and Ic supernovae are unusual supernovae that have most of the properties of type II *Types Ib and Ic supernovae are unusual supernovae that have most of the properties of type II supernovae, except that their spectra show no hydrogen lines.supernovae, except that their spectra show no hydrogen
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