The text presents a compilation of final exam questions and detailed answers related to the study of galaxies, stars, and the universe, focusing on gravitational interactions, stellar evolution, and cosmic phenomena. Key concepts include the movement of galaxies relative to the Milky Way, the forma...
FINAL EXAM QUESTIONS WITH ACTUAL DETAILED ANSWERS
OF CURRENTLY TESTING SOLUTIONS ASTR 1020
Owing purely to the effects of the gravitational force between individual galaxies, which of the following
should be true? - ANSWER-Some galaxies should be moving towards the Milky Way, and others should
be moving away from it.
Based on what you have learned in previous chapters, which of the following measurements would we
use to determine which galaxies are moving toward or away from the Milky Way? - ANSWER-The
Doppler Shift of spectral lines within the galaxies spectrum.
Given that elliptical galaxies are relatively round, ranging in shape from spheres to more squished
spheroids similar to an American football, which of the following statements most accurately describes
the orbits of stars in an elliptical galaxy? - ANSWER-The stars all have irregular orbits in all directions
around the center
On the basis of the colors and lifetimes of different types of stars, which of the following statements best
describes the current state of the bulge and disk? - ANSWER-New stars are forming mostly in the disk.
choose the statement that best describes why there is more star formation in the disk. - ANSWER-There
is more cold, dense gas in the disk than in the bulge
which of the following most accurately describes the spiral arms? - ANSWER-The stars move in and out
of the arms while they rotate around the galaxy center.
What effect would you expect this (spiral arms) to have on stars? - ANSWER-There will be more star
formation inside the spiral arms
Think about what you have learned about stars and galaxies so far, and determine which of the following
statements is correct.
, Choose one:
A. Both red and blue stars form inside the spiral arms. Then the red stars move out of the arms, while
the blue stars stay inside them.
B. Both red and blue stars form everywhere equally within the disk of the galaxy, then something
happens to clear the blue stars out from in between the arms.
C. Both red and blue stars form inside the spiral arms. Then both stars begin to move out of the arms,
but the blue stars die before they can get very far.
D. Red stars form in between the spiral arms, whereas blue stars form inside them. - ANSWER-C
Based purely on your observations of this plot, which of the following statements best describes the
visible distribution of mass within that galaxy? - ANSWER-The highest concentration of mass is in the
center of the galaxy, and it decreases with increasing distance from the center.
Considering how the predictions compare to the observations, what does this imply about the mass
distributed in the galaxy? - ANSWER-The observations show higher velocities than is predicted, mostly in
the outer regions of the galaxy, indicating that there is more mass in the outer regions than we can see.
An elliptical galaxy may appear round if - ANSWER-it has one axis shorter than the other two but is
viewed parallel to the short axis, all three axes are the same; it is spherical in shape, all three axes are
different lengths, but it is viewed from a special angle, and it is elongated along one axis, but it is viewed
parallel to the long axis.
When viewed edge on, a spiral galaxy often - ANSWER-has a dark line across the middle
Hubble's law was discovered using measurements of two properties of a galaxy: - ANSWER-distance and
recession velocity
Which plot most closely matches the observed rotation curve of spiral galaxies? - ANSWER-Increase peak
then levels out
Astronomers know that dark matter is present in galactic halos because the speeds of orbiting stars
_________ far from the center of the galaxy. - ANSWER-remain about contant
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card or Stuvia-credit for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller DrJudy. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for $20.99. You're not tied to anything after your purchase.
