Unit 11 Homework (9)
docx
keyboard_arrow_up
School
Polk State College *
*We aren’t endorsed by this school
Course
1002
Subject
Astronomy
Date
Dec 6, 2023
Type
docx
Pages
2
Uploaded by jesusmol
1.
Explain clearly why the changes in a star's core as it leaves the main sequence cause the
star to increase in radius and become a red giant.
Because of the fusion of the star-like hydrogen and helium components, changes in a star's core when it
exits the main sequence led the star to grow in radius and become a red giant. When the fusion of
hydrogen changes to make helium changes inside the star, the temperature, size, and brightness of the
star vary.
2.
Explain why an aging low-mass star forms a planetary nebula and why the nebulae
shine.
Because the star can no longer maintain itself, an aged low-mass star creates a planetary nebula,
and the nebulae light owing to UV radiation within the nebulae.
3.
What is a white dwarf? Why are they located in the lower left of an HR diagram?
A white dwarf is a small dense star that is close in size to planets. They are within the lower left of an HR
diagram due to their low luminosity and small size.
4.
How is the core of an evolved high-mass star different than the core of an evolved low
mass star? How are their evolutionary tracks on the HR diagram different
The core of an evolved high-mass star is different from that of an evolved low-mass star because
of the fusion that each goes through. A low-mass star will burn slower than that of a high mass
and the difference between the pressure and temperature of each.
5.
Explain what happens in the last few days of a high-mass star's evolution that causes a
core-collapse supernova.
In the last few days of a high-mass star's evolution, the star goes through a reaction that causes
neutrinos to expand and expel to the star's outer layer, which causes a core-collapse supernova.
6.
Briefly describe how a Type I supernova happens. Why do these happen only in
binary star systems?
A Type I supernova occurs after a white dwarf cannot support itself any longer and goes through the
reactions to allow the core to contract to allow the Type I supernova.
7.
Why are supernova explosions important for life on Earth?
Supernova explosions are essential for life on Earth because of the elements produced after the
explosions, such as iron.
8.
How do astronomers use stellar evolution and the H-R diagram to measure the age of
star clusters?
Astronomers use stellar evolution and the H-R diagram to measure the age of star clusters by the
primary sequence point and use it to compare to other models.
Your preview ends here
Eager to read complete document? Join bartleby learn and gain access to the full version
- Access to all documents
- Unlimited textbook solutions
- 24/7 expert homework help