Type II supernovae result from massive stars running out of fuel and collapsing under their own gravity. Some Type II supernovae interact with surrounding material, while others may lose their hydrogen envelopes due to tidal interactions with companion stars. Supernovae are sites of nucleosynthesis, producing heavier elements through nuclear fusion and reactions during the explosion. The r-process occurring in Type II supernovae is responsible for producing about half of the elements heavier than iron. Our Sun will not become a supernova at the end of its life due to insufficient mass, instead expanding into a red giant and fading as a white dwarf. Several large stars in the Milky Way, such as Rho Cassiopeiae and Eta Carinae

1. 1

3. 3

4. What causes a sr to blow up?
4

5. 5

7. 7

8. 8

10. 10

12. 12

15. OF THE TYPE II SUPERNOVAE WITH UNUSUAL
FEATURES IN THEIR SPECTRA
TYPE IIN SUPERNOVAE MAY BE PRODUCED BY THE
INTERACTION OF THE EJECTA WITH CIRCUMSTELLAR
MATERIAL.
TYPE IIB SUPERNOVAE ARE LIKELY MASSIVE
STARS WHICH HAVE LOST MOST, BUT NOT ALL, OF
THEIR HYDROGEN ENVELOPES THROUGH TIDAL
STRIPPING BY A COMPANION STAR.
THE PEAK ABSOLUTE MAGNITUDE OF TYPE II
SUPERNOVAE VARIES FROM ONE TO ANOTHER, BUT

18. THE HEAVIER ELEMENTS ARE PRODUCED BY NUCLEAR
FUSION (FOR IRON-56 AND LIGHTER ELEMENTS), AND
BY NUCLEOSYNTHESIS DURING THE SUPERNOVA
EXPLOSION FOR ELEMENTS HEAVIER THAN IRON.
SUPERNOVAE ARE CANDIDATE SITES FOR THE R-
PROCESS, WHICH IS A RAPID FORM OF
NUCLEOSYNTHESIS. THE REACTIONS PRODUCE
HIGHLY UNSTABLE NUCLEI THAT ARE RICH IN
NEUTRONS WHICH ARE UNSTABLE AND RAPIDLY BETA
DECAY INTO MORE STABLE FORMS.
THE R-PROCESS REACTION, WHICH IS LIKELY TO
OCCUR IN TYPE II SUPERNOVAE, PRODUCES ABOUT

19. THE SUN DOES NOT HAVE ENOUGH MASS TO BECOME
A SUPERNOVA
WHEN THE SUN COMES TO THE END OF ITS LIFE (IN
ABOUT 5 BILLION YEARS) IT WILL SLOWLY EMERGE
INTO A RED GIANT. THE DYING SUN WILL THEN THROW
OFF ITS OUTER LAYERS, FORMING A NEBULA. THE
ONLY OBJECT REMAINING WILL BE THE EXTREMELY
HOT CORE, WHICH WILL SLOWLY COOL AND THEN
FADE AS A WHITE DWARF OVER MANY BILLIONS OF
YEARS.
OUR SUN IS PROBABLY THE THIRD STAR TO EXIST IN
THIS COSMIC NEIGHBOURHOOD, AND OUR SOLAR

20. SEVERAL LARGE STARS WITHIN THE MILKY
WAY HAVE BEEN SUGGESTED AS POSSIBLE
SUPERNOVAE WITHIN THE NEXT MILLION
YEARS. THESE INCLUDE
RHO CASSIOPEIAE
ETA CARINAE,
RS OPHIUCHI,
U SCORPII,..........
SEVERAL REMAIN UNKNOWN AS THEY MAY BE
IN WHITE DWARF STAGE OF TYPE IA.