MASTERING ASTRONOMY FINAL ACTUAL EXAM 2024-2025
NEWEST VERSION QUESTIONS AND CORRECT DETAILED
ANSWERS GRADED A+
You observe a red giant star. What is happening to that star? -Answer-It is
increasing in size, and is fusing hydrogen in a shell around its core.
If the Sun somehow acquired more hydrogen and helium and doubled in
mass, what would happen to it? -Answer-It would evolve more quickly than
it is now.
The ultimate fate of our Sun is to _________. -Answer-become a white
dwarf that will slowly cool with time
What percentage of a star's total lifetime is spent on the main sequence? -
Answer-90%
The best measurements of the mass of the black hole at the galactic center
come from -Answer-the orbits of stars in the galactic center
Where are most of the Milky Way's globular clusters found? -Answer-in the
halo
Which kind of star is most likely to be part of the spheroidal population? -
Answer-M star
If we could view our galaxy from a distance of several hundred thousand
light-years, it would appear ________. -Answer-as a flattened disk with a
central bulge and spiral arms
The Sun's location in the Milky Way Galaxy is ________. -Answer-in the
galactic disk, slightly over halfway out from the center
What is the approximate diameter of the disk of the Milky Way? -Answer-
100,000 light-years
What kinds of objects lie in the halo of our galaxy? -Answer-globular
clusters
, What kinds of objects lie in the disk of our galaxy? -Answer-O and B stars,
open clusters, old K and M stars, and gas and dust
Approximately how far is the Sun from the center of the galaxy? -Answer-
27,000 light-years
What is a planetary nebula? -Answer-the expanding shell of gas that is no
longer gravitationally held to the remnant of a low-mass star
What happens to the core of a star after the planetary nebula stage? -
Answer-becomes a white dwarf
True or False: Stars with high masses live longer than stars with lower
masses. -Answer-false
True or False: Our Sun will end its life in a planetary nebula and become a
white dwarf. -Answer-true
Why are stars unable to fuse iron in their cores? -Answer-The fusion of iron
would take more energy than it produces.
A spinning neutron star has been observed at the center of a ________. -
Answer-supernova remnant
In order to predict whether a star will eventually fuse oxygen into heavier
elements in its core, you need to know what fact about the star? -Answer-
its mass
Why does stellar main-sequence lifetime decrease with increasing stellar
mass? -Answer-Higher core temperatures cause fusion to proceed much
more rapidly.
What happens when the gravity of a massive star's collapsing core is able
to overcome neutron degeneracy pressure? -Answer-The core contracts
and becomes a black hole.
Why do virtually all the galaxies in the universe appear to be moving away
from our own? -Answer-Because expansion causes all galaxies to move
away from nearly all others
NEWEST VERSION QUESTIONS AND CORRECT DETAILED
ANSWERS GRADED A+
You observe a red giant star. What is happening to that star? -Answer-It is
increasing in size, and is fusing hydrogen in a shell around its core.
If the Sun somehow acquired more hydrogen and helium and doubled in
mass, what would happen to it? -Answer-It would evolve more quickly than
it is now.
The ultimate fate of our Sun is to _________. -Answer-become a white
dwarf that will slowly cool with time
What percentage of a star's total lifetime is spent on the main sequence? -
Answer-90%
The best measurements of the mass of the black hole at the galactic center
come from -Answer-the orbits of stars in the galactic center
Where are most of the Milky Way's globular clusters found? -Answer-in the
halo
Which kind of star is most likely to be part of the spheroidal population? -
Answer-M star
If we could view our galaxy from a distance of several hundred thousand
light-years, it would appear ________. -Answer-as a flattened disk with a
central bulge and spiral arms
The Sun's location in the Milky Way Galaxy is ________. -Answer-in the
galactic disk, slightly over halfway out from the center
What is the approximate diameter of the disk of the Milky Way? -Answer-
100,000 light-years
What kinds of objects lie in the halo of our galaxy? -Answer-globular
clusters
, What kinds of objects lie in the disk of our galaxy? -Answer-O and B stars,
open clusters, old K and M stars, and gas and dust
Approximately how far is the Sun from the center of the galaxy? -Answer-
27,000 light-years
What is a planetary nebula? -Answer-the expanding shell of gas that is no
longer gravitationally held to the remnant of a low-mass star
What happens to the core of a star after the planetary nebula stage? -
Answer-becomes a white dwarf
True or False: Stars with high masses live longer than stars with lower
masses. -Answer-false
True or False: Our Sun will end its life in a planetary nebula and become a
white dwarf. -Answer-true
Why are stars unable to fuse iron in their cores? -Answer-The fusion of iron
would take more energy than it produces.
A spinning neutron star has been observed at the center of a ________. -
Answer-supernova remnant
In order to predict whether a star will eventually fuse oxygen into heavier
elements in its core, you need to know what fact about the star? -Answer-
its mass
Why does stellar main-sequence lifetime decrease with increasing stellar
mass? -Answer-Higher core temperatures cause fusion to proceed much
more rapidly.
What happens when the gravity of a massive star's collapsing core is able
to overcome neutron degeneracy pressure? -Answer-The core contracts
and becomes a black hole.
Why do virtually all the galaxies in the universe appear to be moving away
from our own? -Answer-Because expansion causes all galaxies to move
away from nearly all others
