Supernovae and their Remnants July 4, 1054 event  Chinese, Japanese maybe even Anasazi record a new star in Taurus  Peak apparent magnitude = -5 Supernova Light Curves  Two classes  Type 1: Bright at its peak. Bright, fast decaying  Type 2: Doesn’t get as bright at its maximum much long, but lasts longer. Dimmer, slower decaying Type II SN – observations  High mass stars  Not as bright, slower dimming  Find compact object in center:  Neutron Stars  Black Holes The Problem w/ Iron!  Hydrogen, Helium, Carbon, Oxygen = Fusion releases energy  Uranium, Lead = Fission releases energy  Iron cannot fuse because it cannot make matter from energy  Iron cannot fission  Iron will collapse under gravity  Iron core mass > 1.44 M Sun  Electrons & Protons are smashed into Neutrons and then they burst into Neutrinos Type II SN – theory  Fusing shells, Iron core  Collapsing core  P + e  N  Gamma rays and neutrinos are emitted  Implosion sends out a shock wave when neutron core recoils  Neutron star or black hole is left  Star explodes because the dense matter transfers its momentum to light particles SN 1987A  First SN in 1987  Supernova (SN) in Large Magellanic Cloud  Closest one in modern times  Neutrinos detected confirm theory Supernova Light Curves  Brightness vs. Time  Powered by Radioactive decay: 56 56 56  Ni  Co  Fe  Evidence in the light curve shape Nucleosynthesis (all elements > Zn)  Neutron Capture – free neutrons are capture by a heavy nucleus  “Slow” or