Download Name: Notes – #51 Our Suns Brilliant Future 1. In the core of our

Name: ___________________________
Notes – #51 Our Suns Brilliant Future
1. In the core of our Sun, energy is produced because the fusion of the 4 protons is slightly
____________ massive than the helium nucleus that is formed. (Remember E = mc2)
2. Since 4 protons fuse into 1 helium nucleus, the number of particles in the Sun’s core is
decreasing. As the number of particles decreases, the temperature gradually ________.
As a result the ___________________ will also gradually rise.
3. Describe Earth in about one billion years from now.
4. What is likely to lead to mass extinctions prior to the Earth’s oceans boiling away?
5. When the Sun was much younger, its luminosity was about ______ percent lower than it is
today.
6. Over the course of the next 5 billion years, its core will become comprised mostly of
___________. Nuclear reactions will stop because the electric ____________ of the
helium nuclei (+2 charges each) will be significantly greater than between the protons (+1
charge each). The helium core will slowly gravitationally ________________. As the
core contracts, its temperature will ____________________.
7. The contracting helium core leads to an ____________________ of the rest of the
star. The expanding atmosphere of the Sun will ____________. As a result, its color
will become more _________. It will then be called a _________________.
8. Our Sun will be perhaps _________ times more luminous that it is today because of the
actively burning ________________ shell.
9. As a red giant, the Sun will move off the Main Sequence. It temperature will go
___________ and its luminosity will go _____________.
10. Once the temperature of the core reaches ______________________ degrees K, 3
helium nuclei can come together (i.e. fuse) to form a ________________ nucleus.
11. Carbon can fuse to a helium nucleus to form ________________.
12. The helium fusion stage lasts only about ________________ years.
13. At this stage, there is a carbon and oxygen core surrounded by a ______________
fusing shell which is surrounded by a ______________ fusing shell.
14. The outer layers of the Sun’s atmosphere in this bloated red giant stage can be ejected
into space called a ____________________ because gravity is not _____________
enough to hold on to it.
15. The glowing ejected shell of gas is called a ________________________________.
16. Sometimes there is a ____________ of gas surrounding the star that inhibits gas from
being ejected in that direction. As a result, a bipolar ejection is seen.