Solar System 2014 STATES
Solar System — 2014 — Answer sheet
Station A (1 pt per question unless marked otherwise)
A1.
A7.
A13.
A19.
A2.
A8.
A14.
A20.
A3.
A9.
A15.
A21.
A4.
A10.
A16.
A5.
A11.
A17.
A6.
A12.
A18.
Station B (B1-B10 1 point each;
B11-B20 ½ point per blank)
B1.
B7.
B12. M
B15. M
B18.M
B2.
B8.
O
O
O
B3.
B9.
B13. M
B16. M
B19.M
B4.
B10.
O
O
O
B5.
B11. M
B14. M
B17. M
B20.M
B6.
O
O
O
O
Station C (1 pt per question unless marked otherwise)
C1.
C3.
C5.
C7.
C9.
C2.
C4.
C6.
C8.
C10.
C11.
C12.
C13.
K °C
C15.
C14.
K °C
C16.
C17. (2)
°C
Station D (points per question given in parentheses)
D1. (2)
g/cm3
D5. (1)
D2. (2)
g/cm3
D6. (2)
D8. (2)
yrs
D9. (2)
m3
D10. (2)
m3
D4. (2)
g/cm3
(1)
kg/m3
D11. (4)
Tiebreakers: Section 3 subscore, section 2 subscore, time
atm
D3. (1)
D7. (1)
kg/m3
°C
kg/m3
Solar System 2014 STATES
Solar System — 2014 — Answer Key
Station A (1 pt per question unless marked otherwise)
A1. Tiger stripes
A7.
B
A13. Triton
A19. D
A2. Enceladus
A8.
C
A14.
F
A20. Cycloids
A3. Saturn
A9.
Mars
A15.
B
A21. B
A4. Titan
A10. Europa
A16.
A
A5.
D
A11. Jupiter
A17.
C
A6.
A
A12.
A18. Mars
C
Station B (B1-B10 1 point each;
B11-B20 ½ point per blank)
B1.
F
B7.
A
B12. M Cassini
B2.
C
B8.
F
O Iapetus
B3.
I
B9.
G
B13. M Cassini
B4.
D
B10.
D
B5.
E
B11. M Voyager 2 B14. M Voyager 1 B17. M Pathfinder B20.M Voyager 1
B6.
F
B15. M Viking 1
O Mars
O Triton
B16. M Galileo
B19.M Vega (2)
O Europa
O Comet Halley
O Titan
O Europa
B18.M Voyager 2
O Enceladus
O Mars
O Earth
Station C (1 pt per question unless marked otherwise)
C1.
F
C3. G IC  IX
C5. G VIIIVII C7.
C2.
C
C4.
C6.
B
E
D
C9.
A
C8. G XIX
C10.
B
C11. Critical point
C13. Supercritical fluid
C15.
XI
C12. 647
K
374 °C
C14. 410
K
140 °C
C16. 80
C17. (2) Decreases,
°C
then increases
Station D (points per question given in parentheses)
D1. (2) 2.0
g/cm3
D5. (1) 999.84
D2. (2) 1.0
g/cm3
D6. (2) 4.12
D3. (1) B
D4. (2) 2.5
g/cm3
kg/m3
°C
D8. (2) 7.6
yrs
D9. (2) 1.3 x 106
m3
m3
D7. (1) 999.70
kg/m3
D10. (2) 3.7 x 1022
(1) 999.97
kg/m3
D11. (4) 4 x 10-15
atm
-12
or (2) 1 x 10
atm
Tiebreakers: Section 3 subscore, section 2 subscore, time
Solar System 2014 STATES
Station A
Image identification
Instructions
Use the images provided to answer the questions.
For questions that ask what an object orbits, give the closest larger object.
For example, the Earth orbits the Sun, but the Moon orbits the Earth.
All questions at this station are worth one (1) point.
Solar System 2014 STATES
Questions A1-A3 use the picture below.
A1. What prominent features
appear in the bottom right fourth
of the image?
A2. What is the name of the
object shown?
A3. What does this object orbit?
Questions A4-A6 use the picture below.
A4. This image is a reconstruction based
off of radar data from the Huygens
probe. What object is shown here?
A5. The surface temperature was
recorded to be -180° C. Is the liquid
visible in the picture water?
A. Yes, because oceans are made of
water.
B. Yes, because only water exists in
sufficient amounts to fill that volume.
C. No, because it’s actually solid ice.
D. No, because it’s actually liquid
methane.
A6. Additional findings suggest that the surface of this object is a dozen or so rocky masses that
move on top of a sub-surface ocean of liquid water. This is very similar to which terrestrial
process or event?
A. Tectonic plates
B. Magma plumes
C. Pangaea
D. Mid-oceanic ridges
Solar System 2014 STATES
Questions A7-A9 use the picture below. It is a true-color image a few tens of
meters on each side.
A7. What is the dark object visible at the center of the
image?
A. Volcanic caldera
B. Meteor impact crater
C. Bad pixels on the camera
D. The shadow of a moon
A8. What is the white material surrounding the dark
spot?
A. Clouds around a mountain
B. Reflected sunlight off a lake
C. Exposed water ice
D. Polar ice cap
A9. The color of the ground in this picture is largely due to iron oxide. What planet, moon, or
other object is shown here?
Questions A10-A12 use the picture below.
A10. What object, with a subsurface ocean beneath
an icy crust, is illustrated in the picture at left?
A11. What does this object orbit?
A12. Suppose detailed images of the surface of this
object showed a very smooth surface with few large
features like craters or impact basins. Would this
suggest that the surface is old or young, and why?
A. Old, because erosion would have eliminated
large features.
B. Old, because this object is in the far outer
Solar System.
C. Young, because an old surface would show
craters and other markers of meteor
bombardment.
D. Young, because this object formed very recently.
Solar System 2014 STATES
Questions A13-A15 use the picture below.
A13. Which moon is pictured at left?
A14. The moon shown here orbits which planet?
A. Earth
D. Saturn
B. Mars
E. Uranus
C. Jupiter
F. Neptune
A15. In the lower half of the image is terrain named
after which fruit?
A. Pomegranate
C. Watermelon
B. Cantaloupe
D. Lemon
Questions A16-A18 use the picture below.
A16. The “scallop formations” shown in the picture
at right are evidence of what kind of water/ice?
A. Permafrost
C. Glaciers
B. Dried lake beds D. Subsurface lakes
A17. The shapes are caused by water undergoing
what phase change?
A. Melting
C. Sublimation
B. Freezing
D. Deposition
A18. Where was this photograph taken?
Questions A19-A21 use the picture below.
A19. Which moon is shown in the picture at
left?
A. Ceres
C. Iapetus
B. Triton
D. Europa
A20. What feature of this moon is identified by
arrows and traced in red?
A21. What is the cause of the feature
identified in the photo?
A. Impact events
C. Precipitation
B. Tidal forces
D. Geysers
Solar System 2014 STATES
Station B
Space exploration missions
Instructions
Read the directions for each activity, and answer the questions using your
response sheet.
For questions that ask what an object orbits, give the closest larger object.
For example, the Earth orbits the Sun, but the Moon orbits the Earth.
Unless specified otherwise, all questions are worth one (1) point.
Solar System 2014 STATES
For questions B1-B10, match the mission in the left column with the object in the
right column that it explored (or is exploring, or will explore). You may reuse
answer choices if needed. Write the letter, not the name, on your answer sheet.
B1. Viking 1
B2. Dawn
B3. Cassini
B4. Vega 2
B5. Huygens
B6. MSL Curiosity
B7. Galileo Orbiter
B8. Pathfinder
B9. New Horizons
B10. Stardust
A.
B.
C.
D.
E.
F.
G.
H.
I.
Europa
Triton
Ceres
A comet
Titan
Mars
The Kuiper Belt
The Oort Cloud
Saturn
For questions B11-B20, you have been given a list of images of objects, as well as
the year that the photograph was taken. For half (½) a point each, write the
Mission that took the image and the Object of the image on your answer sheet.
B11. Taken in 1979
B12. Taken in 2007
B13. Taken in 2005
B14. Taken in 1980
Solar System 2014 STATES
B15. Taken in 1976
B16. Taken in 1996
B17. Taken in 1997
B18. Taken in 1989
B19. Taken in 1986
B20. Taken in 1990 (object is in blue circle)
Solar System 2014 STATES
Station C
Phases of water
Instructions
Use your own knowledge, and the chart provided, to answer questions
about the various phases of water and water ice.
Unless specified otherwise, all questions are worth one (1) point.
Solar System 2014 STATES
For questions C1-C10, choose from the following list of phase changes:
A. Freezing
B. Melting
C. Vaporization
D. Condensation
E. Sublimation
F. Deposition
G. Solid-solid
You will be given an initial temperature and pressure, as well as a change in one
quantity. On your answer sheet, write the letter (not the name) of the first
phase transition that will occur. If you choose “Solid-solid”, for an additional 1
point, list the two crystalline varieties involved in the phase transition. Write
them in the form “Start  End”, e.g. “XI  II”.
Initial temp
C1. 400 K
C2. 200° C
Initial pressure
100 Pa
20 MPa
Action
Decrease temperature
Decrease pressure
C3. 100 K
C4. 10° C
3 bar
1 bar
Increase pressure
Increase pressure
C5. 160 K
C6. -90° C
100 kbar
10 Pa
Increase temperature
Increase temperature
C7. 300° C
C8. 273 K
15 bar
0.5 TPa
Decrease temperature
Decrease pressure
C9. 290 K
C10. -65° C
0.3 bar
400 bar
Decrease temperature
Increase temperature
For questions C12 & C14 below, circle on your answer sheet the unit you used.
C11. Above a certain temperature, water’s liquid and gas phases are no longer separate. What
is the name of that temperature & pressure?
C12. What temperature is mentioned in question C11? You may give your answer in K or °C,
with no more than 3 significant figures.
C13. Above the temperature mentioned in C11, in what phase does water exist?
C14. A very robust pressure cooker might be able to maintain a pressure of 3 atmospheres.
What is the boiling point of water at this pressure? You may give your answer in K or °C, with
no more than 2 significant figures.
C15. Which crystalline variety of ice are you likely to find in Kuiper Belt objects, very far from
the Sun or any other source of heat?
C16. Titan may have a subsurface layer of the ice-VI crystal. In °C, to one significant figure,
what is the hottest that a layer of pure ice-VI could be?
C17. (2 pts) Under increasing pressure, what happens to the freezing point of liquid water?
Solar System 2014 STATES
Solar System 2014 STATES
Station D
Numerical questions
Instructions
All questions at this station involve numbers and calculations. Use the
provided calculator and scratch paper to do your work, and record only your
answer on your response sheet.
If there is a problem with the calculator, or you run out of scratch paper,
raise your hand and someone will (quickly!) bring you more.
The point value of each question is given in parentheses here and on your
response sheet.
Solar System 2014 STATES
Questions D1-D4 use the following equation:
Dave 
PH 2O  3Prock
100
In the equation, Dave is the average density of a body (in grams per
cubic centimeter, or g/cm3). PH2O & Prock refer to the percentage of
the material that is water/ice or rock, respectively; and no other
material (besides those two) is used in the problems below.
D1. (2 pts) What is the density of an object that is 50% water and 50% rock, in g/cm 3? If you get
a decimal, give it to the nearest tenth.
D2. (2 pts) What is the density of an object that is entirely water, in g/cm3? If you get a
decimal, give it to the nearest tenth.
D3. (1 pt) The density of Enceladus has been measured to be 1.61 g/cm3. Therefore, Enceladus
must be composed…
A. Entirely out of water/ice
D. Mostly out of rock
B. Mostly out of water/ice
E. Entirely out of rock
C. Of roughly equal parts water/ice and rock
D4. (2 pts) What is the density of an object that is three quarters rock, in g/cm 3? If you get a
decimal, give it to the nearest tenth.
Questions D5-D7 use the following equation:
DH 2O  0.00778  T 2  0.0641 T  999.840
Questions D1-D4 assumed that water and ice have a constant density. This isn’t quite true—in
fact, there is a slight dependence on temperature. Between 0°C and 10°C, the density of water
can be modeled using the above equation. In the equation, DH20 is the density of water (in
kilograms per cubic meter, or kg/m3) and T is the temperature (in degrees Celsius, or °C).
D5. (1 pt) What is the density of water just before it freezes into solid ice, in kg/m3? Give your
answer to two decimal places.
D6. (2 pts) At what temperature does water reach its maximum density between 0°C and 10°C?
Give your answer to two decimal places.
D7. (2 pts, 1 each) What are the minimum and maximum densities of water, in kg/m3, between
0°C and 10°C? Give your answers to two decimal places.
Solar System 2014 STATES
Questions D8-D11 are about Saturn’s E ring, which may be due to cryovolcanism
on the moon Enceladus.
D8. (2 pts) The mass of the E ring is estimated to be 1.2 x 109 kg. Ice geysers on Enceladus have
been measured ejecting 5 kg of matter every second from the moon’s gravitational field. At
this rate, how many years (ignoring leap days) would it take to create the E ring? Give your
answer to two significant figures. (Data from Ingersoll & Ewald 2011)
D9. (2 pts) If the entire E ring were compressed into a solid mass of ice, what would its volume
be, in cubic meters? Use the mass from question D8, and assume the density of ice is 916.7
kg/m3. Use scientific notation, and give your answer to two significant figures.
D10. (2 pts) The volume of a torus (donut shape) is V =
2π2Rr2, where R and r are illustrated in the image at right.
For Saturn’s E ring, R is 238,000 km, and r is approximately
5,000 km (this isn’t exactly true, but close enough for now!).
Treating Saturn’s E ring as a torus, what is its volume, in
cubic meters? Use scientific notation, and give your answer
to two significant figures.
D11. (4 pts) Use the ideal gas law, PV = nRT, to estimate the pressure within the E ring. In this
equation,
P is the pressure in atmospheres,
V is the volume in cubic meters,
n is the number of moles of gas,
R = 8.21x10-5 is the ideal gas constant,
and T is the temperature in Kelvins.
You will also need to know that one mole of water vapor has a mass of 18 grams, re-use the
volume from question D10, and you may assume that the temperature in the E ring is a
constant 25 Kelvins. Use scientific notation, and give your answer to one significant figure. If
you did not get an answer to D10, you may use a value of 1.0x1020 for the volume of the E ring
for 2 points instead of 4.