Download 3rd Astronomy Exam: The Solar System and the Sun 14 April 2014

3rd Astronomy Exam: The Solar System and the Sun
14 April 2014
Name_____________________________________________
Class Meeting Time_____________________
1. Describe the how the Sun produces its energy by describing the net proton-proton chain. Describe all the
components of the reactions and address the origin of the components. Use this page only for your response.
2. In a few sentences describe how the deadly gamma rays from the Sun’s core are transformed to benign visible
and infrared photons.
3. Although most astronomy students learn the Sun can be divided into three interior layers, we have chosen to
describe the Sun as just composed of two layers: a core and envelope. In the table below list, as best you can,
the functions and properties of these two layers. Extra points awarded for correct quantitative answers.
Function and Properties of the Core
Function and Properties of the Envelope
Answer the following multiple choice questions regarding the vital statistics of the Sun (i.e. its bulk structure)
4. Which of the numbers below best represents the mass of the Sun in Earth masses?
a. 300
c. 30,000
e. 3,000,000
b. 3,000
d. 300,000
5. Which of the numbers below best represents the radius of the Sun in Earth radii?
a. 100
c. 10,000
b. 1,000
d. 100,000
e. 1,000,000
6. Which of the numbers below best represents the volume of the Sun in Earth volumes?
a. 100
c. 10,000
b. 1,000
d. 100,000
e. 1,000,000
7. Which of the numbers below best represents the temperature of the Sun’s photosphere in Kelvins?
a. 2,000
c. 50,000
e. 10,000, 000
b. 6,000
d. 100 ,000
8. Which of the numbers below best represents the temperature of the Sun’s core?
a. 6,000
c. 100 ,000
b. 50,000
d. 10,000, 000
e. 100,000,000
9. The Solar Nebula Theory (a.k.a. The Condensation Model) predicts that there should be only two types of
planets in a planetary system. List five properties of the Jovian planets that are distinctly different from those of
the terrestrial planets by listing the properties of the average Jovian planet in our solar system. Extra points
awarded for correct quantitative answers
10. As a half-time lesson during a college foot ball game, you have conscripted eight cheerleaders to carry large
decorated spheres that represent the eight planets in our Solar System. You tell them that the Sun will be on
the zero yard line and that they are to place themselves down the center of the field at representative distances
from the Sun. You also tell them that each yard on the field represents 1 AU. On the diagram below mark the
positions each cheerleader should occupy and the planet they represent. Be precise.
Sun on the
zero yard line.
0
10
0
10
20
30
20
40
30
50
40
40
50
30
40
20
30
10
20
10
0
0
11. Imagine that you have a part-time job that makes you $10,000 a year. Further imagine that this amount of
income represents the mass of the Earth. Which of the jobs with their listed salaries would best represent the
mass of Jupiter?
a. Burger Cook at McDonalds - $20,000 a year
b. College Professor - $50,000 a year
c. Successful small Business Owner- $150,000 a year
d. Wall Street Stock Trader - $300,000 a year
e. CEO of Disney Corporation - $3.2 Million a year
12. Which of the terrestrial planets is the largest? ________________________________
13. Which of the Jovian planets is the smallest?_________________________________
14. How many times larger in mass is the smallest Jovian planet compared to the largest terrestrial planet?________
15. In a few sentences describe why, according to the Solar Nebula Theory, terrestrial planets are predicted to be
small in mass and radius, high in density and close to the Sun.
16. In another few sentences describe how, according to the Solar Nebula Theory, the Jovian planets are predicted
to be so large in mass and radius, low density and far from the Sun.
17. For which of the reasons below is Venus sometimes called “Earth’s twin”?
a. The atmosphere of Venus contains N2 and O2 just like the Earth.
b. The mass and radius of Venus is just about the same as those of the Earth.
c. Venus has one moon orbiting it just as the Earth does.
d. The Venus spins at the just about the same rate as the Earth so that their day lengths are about equal.
e. Venus has a strong magnetic field like the Earth
18. Which of the following is NOT a characteristic of the Jovian planets?
a. They have very few, if any, natural satellites.
b. They all have large quantities of gas.
c. They are primarily made of hydrogen and helium.
d. Their orbits are separated by relatively large distances.
e. They all have ring systems.
19. Which of the ages below corresponds to the age of our solar system?
a. 1 Million Years
d. 10 Billion Years
b. 64 Million Years
e. 13.1 Billion Years
c. 4.6 Billion Years
20. What are the two most abundant gases in an interstellar cloud?
a. ________________________ and __________________________
21. State or identify the source of energy that provided initial heating of the solar nebula even before the Sun was
formed.
a. Friction of dust grains rubbing against each other within the cloud
Radioactive decay of heavy elements like uranium
b. Nuclear fusion of light elements like hydrogen
c. Nearby stars heated the nebula with their star-light
d. Gravitational collapse of the nebular gas was converted into heat
22. The image to the right is of the nucleus of Comet Hartley 2.
The nucleus is only about 2 km long. Comets like this are
examples of which of the following objects?
a. Interstellar dust grain
b. Solar Nebula
c. Planetesimal
d. Dwarf Planet
e. UFO
23. In a few sentences, explain why planetesimals had more material to grow from in the outer parts of the Solar
System than in the inner part.
24. In a few sentences, explain why the density/composition of the planets abruptly changes between the inner and
outer solar system.
25. Which of the processes listed below was responsible for planet growth?
a. Accretion
d. Condensation
b. Coalescence
e. All the above
c. Collisions
26. Scientists are still unsure as to the origin of the Earth’s oceans. Circle the hypotheses below that are currently
be investigated regarding the origin of the Earth’s oceans. (Circle all that apply)
a. Comets delivered water to fill the oceans to the Earth after it had formed.
b. The water came from water rich icy planetesimals that the Earth formed from.
c. The water is out gassed from volcanoes that release the small amount of water bound in the origin rocky
planetesimals the Earth formed from.
d. The water was captured as it evaporated off the Sun’s surface.
e. Water is everywhere so it is natural for the Earth to have oceans.
27. In a few sentences, explain why Saturn’s moon Titan has an atmosphere, but Earth’s moon does not even
though both moons have nearly identical gravity fields and escape velocities.
28. Which of the processes below terminated the formation of the planets in our solar system?
a. All the gas, dust and ice were consumed by the planets leaving no more material left to grow with.
b. A nearby supernova removed all the unbound gas, dust and ice from our system thus starving the planet
formation process.
c. All the rock fell into the Sun and the ice melted and evaporated into space, again, starving the planet
growth process.
d. The initial burst of energy from the newly ”turned on” Sun swept the solar system clear of the raw
materials needed to grow planets.
e. The seventh day ended.
Below are listed ten of the known planets around other stars. The table contains the planet name, mass, semi-major axis
of its orbit and its eccentricity.
Planet Name
Mass in Jupiter Masses
Semi-major Axis of Orbit in AU
Eccentricity
HD 231701 b
1.1
0.53
0.1
HD 93083 b
0.37
0.48
0.14
HD 37124 b
0.64
0.53
0.05
HD 37124 c
0.62
1.64
0.14
HD 37124 d
0.68
3.2
0.2
HD 32518 b
3.0
0.59
0.01
HD 154672 b
5.0
0.6
0.61
HD 11506 b
0.82
0.64
0.42
HD 11506 c
3.4
2.4
0.22
HD 145457 b
2.9
0.76
0.11
Known multiple
exoplanet system
Known multiple
exoplanet system
29. What is the average mass of these planets in Jupiter masses and Earth masses?
a. Average mass = _____________________ = _________________________
30. The average semi-major axis of these planet’s orbits is 1.14 AU. In a few sentences characterize these planets
given their average mass and average semi-major axis and state how they appear to be different from the
planetary systems the Solar Nebula Model would predict.
31. Which of the ten planets above has the most circular orbit?
Planet Name ____________________________
32. Even though we know we are probably not seeing all the planets in the systems above, which of the planetary
systems in the list appears to be most similar to our planetary system,?
Planet Name ____________________________
33. Examine the characteristics of the planet HD 154672 b. Propose a mechanism, in a few sentences, that would
place this planet into the orbit it currently has assuming that it formed farther from its star.
34. The radial velocity graph of a hypothetical planet orbiting a star like our sun is shown below. Without any
complex calculations list the orbital properties of this unseen hypothetical planet orbiting this star than you can
deduce from the radial velocity curve. Answer in a few sentences.
Hypothetical Planet around a Sun-like Star
Radial Velocity, km/s
-10
-15
-20
-25
-30
2000
2000.5
2001
2001.5
Date
2002
2002.5
2003