Download 1 GS106 Lab 1 and 2 Answer Key READING QUESTIONS Four

GS106 Lab 1 and 2 Answer Key
c:\wou\gs106\labkey\lab2key.wpd
READING QUESTIONS
Four phases of moon: new, first quarter, full, third quarter
AU = astronomical unit (a unit of distance) = average distance from Earth to the Sun ~93,000,000
mi
Light Year - distance traveled at the speed of light for a duration of 1 Earth year
Light Minute - distance traveled at the speed of light for a duration of 1 Earth minute
Dist. from Sun to Earth ~93,000,000 mi
23.5 degrees is the angle of tilt of the Earth's axis from perpendicular, relative to the plane of the
ecliptic
Eccentricity - shape of the planetary orbit about the sun (a perfectly circular orbit = 0)
Earth Eccentricity = 0.0167, a relatively circular orbit
Direct Sunlight - focus of sun light is perpendicular to the surface of the Earth (highest amount of
solar radiation or "insolation")
Indirect Sunlight - focus of sun light is at an acute (< 90 deg.) angle relative to the surface of the
Earth (lower insolation)
PRE-LAB ASSESSMENTS
Pre-Existing knowledge will vary according to groups, but here are the important answers for this
section...
List of Planets: increasing away from sun: mercury, Venus, earth, mars, Jupiter, Saturn, Uranus,
Neptune, Plato
Planets we commonly see without a telescope: "evening stars": mercury, Venus, mars... etc.
Why do we have seasons on Earth: because of the 23.5 degree tilt of the Earth's axis of rotation
compared to the plane of the ecliptic, and the revolution of the Earth about the Sun.
What causes phases of the moon?: Position of the Earth and moon relative to the Sun, the
revolution of the Moon about the Sun, and the illuminated vs. shadowed portions of the Moon.
Smallest Planet: Pluto, Largest Planet: Jupiter
How have we deduced the physical properties of the planets without visiting there directly?:
1
Through the use of telescopes and physical relationships, direct visual observation.
1 - Scale Model of the Solar System
Scale of your model varies by groups
Scale of Planet Size (using sun): 34 in (on the model) = 1,392,00 km (diameter on the sun)....
dividing both sides by 34... 1 in (model) = 40,941 km (on the sun)
Spacing of planets pattern: Distance between planets roughly increases with distance away from
the sun
General patterns about sizes of planets:
small interior planets (< radius for Merc., Ven., Earth, Mars)
Large exterior planets (Jup., Sat., Ur., Neptune)
Plato is odd ball... small diameter
2. Sun-Earth-Moon Relations
See Attached Sheets with Moon Phase Diagrams...
Other Related Questions
What is the time between two successive full moons? Space Facts says 27.3 days
Orbital Period of Moon around Earth: 27.3 Days
Time between a full and new moon: ~14 days
Full moon in west...time of day?... in early A.M. (the full moon rises in the east in the evening, and
sets in the west in the AM)
Why do we see phases of the moon?... all because of the orientation of the moon relative to the
sun and the Earth. When the illuminated moon is opposite the sun from the Earth = full moon.
When the shadow of the moon is facing the Earth = New Moon... the moon orbits in a
counterclockwise direction around the Earth, when looking down on the objects, from above.
3 - The Seasons
Direct sunlight photometer reading ~70 microamps
Indirect sunlight photometer reading ~ 35 microamps
Refer to the diagram of Earth seasons (see next page)
2
Other Questions:
More sunlight hits the Earth's surface at the direct angle
The southern and northern hemispheres have opposite seasons because of the 23.5 degree tilt of
the Earth relative to the plane of the ecliptic, and the relation of the sun and Earth as the Earth
orbits around the Sun.
Table Results
Pt. A
Pt. B
Pt. C
Pt. D
S. Hem. Summer
S. Hem. Winter
S. Hem. Fall
S. Hem. Spring
N. Hem. Winter
N. Hem. Summer
N. Hem. Spring
N. Hem. Fall
One Earth Day = rotation of the Earth on it's axis, 1/24 hrs
See Diagram on Next Page for Explanation of Earth Seasons
3
4 - Classifying Planets
Example Grouping of Physical Properties
Inner Planets = denser, smaller diameter, shorter orbital period
Outer Planets (except Plato) = less dense, larger diameter, longer orbital periods
General Patterns of Planets
Inner Planets (Mercury, Venus, Earth, Mars): small diameter, rocky composition, high
density, warm surface temperatures
Outer Planets (Jupiter, Saturn, Uranus, Neptune): large diameter, less dense, cooler
surface temperatures
Which Planet Would Float in Water? - Saturn
Jupiter Day = 9.9 Earth Hours Venus Day = 5832.5 Earth Hours
Earth Years comprising a Jupiter year? = 11.9 Earth Yrs
2 planets with 90% of mass in Solar System: Jupiter and Saturn
Unusually Hot Planet: Venus, why? 96.5% of Venus atmosphere = carbon dioxide (a greenhouse
gas).
Density Relations
Air 833 x less dense than water
Rock 3 x more dense than water
Metal at high pressure: 10,000 x more dense than water
Density comparison / planet composition
Mercury = "rock", Venus = "rock", Earth = "rock", Mars = "rock", Jupiter = "ice and gas",
Saturn = "gas", Uranus = "ice", Neptune = "ice", Plato = "ice and rock"
5 - Graphing Planet Data
Make sure you know how to plot an X-Y graph, see your instructor before the quiz if you don't know
or are rusty.
Graphs vary according to groups and individual students.
General Trends and Relationships
1) Outer planets are more massive than inner, except Pluto (Jupiter is most massive)
4
2) Outer planets have greater radius than inner, except Pluto (Jupter is largest)
3) Outer planets are less dense than the inner
4) The surface temperature decreases with increasing distance from the Sun
5) Orbital period increases with increasing distance from Sun (planet years increase with
distance from sun)
6) It does not appear that surface temperature has any direct relationship to mass, it is
more constrained by distance from Sun
7) The greater the mass, the shorter the rotational period (i.e. faster the rotation), in
general
Post-Lab Assessments (important points)
All models made: solar system (sun/planets), Earth-Moon-Sun relationship, Earth Climate / orbit
Models are visual aids that help understanding concepts.
Planet Characteristics that are similar
Earth
Mass
Density
Atmosphere
Earth
Similar Planets to Earth
Mercury, Ven, Earth, Mars, Pluto
Mercury, Venus, Earth, Mars, Pluto
Earth is Unique (that's why we are here!!!)
Different Planets
Mass
Density
Jupiter, Saturn, Uranus, Neptune
Jupiter, Saturn, Uranus, Neptune
Atmosphere
Mercury, Venus, Mars, Jupiter, Saturn, Uranus, Neptune, Pluto
5