Section 13.B

Question 1

Recognize what sorts of characteristics we observe for a supernova
(4)

Logically, where do we see most supernovas? ___________________

Answer 1

• rarity
• the brightness
• neutrinos
• messy debris
• in our Milky Way? Or other galaxies?

Question 2

Pick the cause of a white dwarf going supernova (Type Ia supernova) ____

 Is there usually anything left after this kind of supernova? ________.

Answer 2

• being it’s getting too heavy, thus collapsing

-

Question 3

what kinds of objects can “go supernova,” realize there are two possible answers that would be correct:

Answer 3

(A) a white dwarf (Type Ia supernova) and…

B) a very heavy star that is dying (Type II supernova

Question 4

Understand the basic details of how a high-mass star prepares to undergo a supernova explosion as it dies.

Answer 4

• These stars have enough weight to make their cores hot enough to undergo additional stages of nuclear fusion burning, so they burn heavier and heavier types of atoms than the Sun will ever burn.
• Eventually, however, no more types of atoms can be fused together generate energy

Question 5

Recall which element is the end of fusion and cannot be further burned ____

Realize it is this barrier that can ______

Answer 5

• the iron limit

- trigger a heavy star to die as a supernova explosion.

Question 6

__________ as the process that breaks up large atoms during a supernova, undoing previous fusion.

• Realize this breaking-up process is _____, not fusion.
• Recognize that this process happens in the collapse of a ___________

Answer 6

• photodisintegration
• fission
• heavy star’s core during the beginning of a supernova

Question 7

Realize the __________ essentially never expands, but collapses

Answer 7

• core of a star

Question 8

During a _____, a short but violent rebound of an over-collapsed over-squeezed core shakes off the rest of the star.

Answer 8

• supernova

Question 9

Recognize that a ball of neutrons (future “neutron star”) forms when ______

Answer 9

the iron core of a dying star collapses (during supernova)

Question 10

compare the brightness of a supernova to that of a whole galaxy

Answer 10

just as bright

Question 11

Know the difference in methods of creation of core-collapse supernovae (Type II) and carbon-detonation supernovae (Ia).

Answer 11

 Recognize the different methods of triggering them (II. heavy star dies and becomes neutron star vs. Ia: white dwarf becomes too heavy and explodes).

- Recognize that in the second kind (Type Ia) even the center of the dying object is exploded away.

Question 12

Be able to pick when the heaviest elements form (like uranium and silver and lead!)

Answer 12

It is during supernova explosions