Download Spring 2014 Astronomy Exam Study Guide (Co-Taught)

SPRING 2014 ASTRONOMY STUDY GUIDE
(CO-TAUGHT)
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THE UNIVERSE AND ITS HISTORICAL ASPECTS
Know and understand the differences in the
understanding of gravity by Isaac Newton and
Albert Einstein.
Know and understand the application of Newton’s
three Laws of Motion
Be able to calculate the age for the Universe using
Hubble’s Law
Example Questions:
1. What things does the force of gravity depend on? (there are two)
2. How does gravity vary with distance between objects?
3. What keeps satellites orbiting the Earth moving along their curved
paths?
4. How is looking at faraway objects equivalent to looking back in time?
5. What is the cosmic microwave background radiation a relic of?
6. How does Einstein’s concept of gravity differ from Newton’s concept of
gravity?
7. Is there a center to the Universe? If so, where is it?
8. What is a light year a measure of?
9. Our Sun obtains its energy through nuclear fusion. Which of the following elements are primarily involved
in this reaction?
10. What was Edwin Hubble one of the first astronomers to determine?
11. What does Einstein’s General Theory of Relativity say about how a massive object affects space-time?
12. What did Einstein’s Special Theory of Relativity determine about how fast anything can move?
13. The theory which might explain the origin of the Universe is called the: ____________________________
THE ELECTROMAGNETIC SPECTRUM AND LIGHT
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Know the relationship between wavelength, frequency, and energy.
Long wavelength = low frequency = low energy
Short wavelength = high frequency = high energy
Understand that as the relative motion of an observer and/or the object
emitting a wave will be shifted toward a slightly different wavelength
(Doppler Effect)
Object moving away from the observer
shifted to a longer wavelength (Redshift)
Object moving toward from the observer
shifted to a longer wavelength (Blueshift)
As the electrons change orbital levels, energy of specific wavelengths is emitted or absorbed
As electrons drop from a higher energy level to a lower energy level, a photon of light is emitted
Example Questions:
14. Which region of the electromagnetic spectrum has the highest frequency?
15. Which region of the electromagnetic spectrum has the longest wavelength?
16. Which region of the electromagnetic spectrum will travel with the fastest speed?
17. Which color of the visible light spectrum has the greatest frequency?
18. Which color of the visible light spectrum has the greatest wavelength?
19. What is the basic difference between different regions of the electromagnetic spectrum?
20. What are photons? What role do they play in absorption/emission? What two things do they transport?
How are they related to electromagnetic waves?
21. What do emission spectral lines and absorption emission lines tell us about the material producing them?
Astronomy Unit Exam Study Guide (Fall 2012) – Page 1
22. What is the primary factor which determines the type of electromagnetic radiation emitted by astronomical
objects?
23. Why are telescopes sensitive to infrared, ultraviolet, X-ray, and gamma-ray wavelengths placed in space
and why is it difficult to observe those wavelengths using land-based telescopes?
ORIGIN AND FORMATION OF THE UNIVERSE
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Understand the concepts related to the formation of the Universe – the Big Bang
Understand the evolution of the Universe from the initial “inflation period” and how what we see today was
formed
Understand the significance of Cosmic Microwave Background Radiation (CMB)
Example Questions:
24. The Universe originated in the Big Bang, a long time ago.
How old is the Universe?
25. What are the two most common elements in the Universe?
26. During the early part of the Universe _____________________ and
_________________________ were created.
27. The Universe is apparently expanding equally in all
directions, where is the center of the Universe?
28. What is the relationship between the distance and
velocities of galaxies?
29. Energy derived from nuclear power plants is a result of
which of the fundamental forces?
STARS, GALAXIES, & THE UNIVERSE
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Be able to identify the stages in the life of a star having the mass similar to our Sun and for stars more
massive than our Sun
Know and understand the end of a stars life and the significance of the end of a massive star’s life
(supernova)
Know that the H-R diagram is based on absolute brightness and temperature
Be able to interpret the H-R diagram (refer to worksheets on the H-R diagram)
Example Questions:
30. A star’s life cycle (how a star lives) is determined by its: _____________________________________________
31. The color of a star can be determined by knowing its: ________________________________________________
32. An exploding star is called a _____________________________________________________________________________
33. Put the following in order of smallest to largest:
a. galaxy, planet, solar system, star, universe
34. Put the following in order of first occurring to last occurring:
a. black dwarf, fusion, main sequence, nebula, planetary nebula, proto-star, red giant, white dwarf
35. Our star and its planets and their moons are collectively called: _______________________________________________
36. If Star A has a red Doppler shift. Star A is moving _____________________________________ the Earth.
Astronomy Unit Exam Study Guide (Fall 2012) – Page 2
Use the H-R diagram to answer questions related to the following concepts:
 Location of stars based on their temperature, luminosity and size.
 Location and color of hottest and brightest stars
 Location and color of coolest and dimmest stars
 Life cycle of various stars
 Location of most stars
 Temperature and luminosity of specific stars
The Lives of Stars
 Stars shine because they are hot
 Primary source of energy is nuclear fusion
 Hydrogen fusion requires temperatures of >15,000,000 0C
 Hydrogen Fusion into Helium is the most common process
 Main Sequence stars generate energy via Hydrogen fusion
 The Main Sequence is a mass sequence:
Low-mass = cool and low-luminosity
High-mass = hot and high-luminosity
 Mass-Luminosity Relationship for stars
 Nuclear Timescale: Dependence of Lifetime on stellar Mass.
Larger Mass = Shorter Life.
The Death of Stars
37. What happens when a low mass star runs out of Hydrogen for fusion in the core?
38. What happens when a low mass star runs out of Helium for fusion in the core?
Low Mass Stars (Like our Sun)
 He core formation & H fusion in outer shell
 Becomes a Red Giant
 He and H fusion shells begin unstable pulsations
 Formation of a Planetary Nebula
 Core becomes a White Dwarf star
High-Mass Stars
 Fuse Helium, then Carbon, Neon, Oxygen & Silicon in successive cores to iron (most stable element)
 Formation of an iron core surrounded by heavy-element fusion shells
 Catastrophic collapse of the Iron Core leading to
 Supernova explosion ejecting envelope
 Core becomes either a neutron star or a black hole
Supernovae
 Creation of heavy elements in the supernova explosion
 Role of supernovae in dispersing interstellar space with heavy elements
General Review Questions:
39. Describe the full life cycle of our sun, including all major stages of its life.
40. Why does a high mass star evolve differently than a low mass star?
41. Why is a Red Giant red in color?
42. Most stars are composed mainly of which element(s)?
43. In Main Sequence stars, what is the relationship between brightness and temperature?
44. What does the apparent brightness, or luminosity, of an object such as a star depend on?
45. Explain the difference between apparent luminosity and absolute luminosity.
46. In what ways is energy transported within the Sun?
47. Describe sunspots in terms of their relationship to “loops” in the Sun's magnetic field.
Astronomy Unit Exam Study Guide (Fall 2012) – Page 3
48. Briefly describe the events leading up to the end of a low mass star's lifetime. How does this differ for a
very high mass star?
49. Why is it sometimes said that humans are “made of stardust”?
50. Why does the sun shine?
Be able to identify these layers of the Sun by: function, description, and on a diagram
Give the letter for each feature of the Sun:
1) _____ Photosphere
2) _____ Chromosphere
3) _____ Corona
4) _____ Core
5) _____ Radiation Zone
6) _____ Convection Zone
7) _____ Solar Flare
8) _____ Solar Prominence
9) _____ Sun Spots
Astronomy Unit Exam Study Guide (Fall 2012) – Page 4