Part 2: Astronomy

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Name: Answer Key Date: Earth Science Period:

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Earth’s Rotation

1. In which direction does Earth rotate? _______________________________________________ 2. What is Earth’s hourly rate of rotation? ______________________________________________ 3. How often does Earth rotate once? _________________________________________________ 4. The diagrams below represent two pieces of evidence that Earth rotates. Identify the evidence

represented by each diagram. Diagram A Diagram B

_____________________________ _________________________________ 5. Toward which direction do wind and water currents deflect towards in the Northern Hemisphere?

______________________________________________________________________________

6. Toward which direction do wind and water currents deflect towards in the Southern Hemisphere?

______________________________________________________________________________

7. The photograph of star trails was taken by an observer in New York State facing north.

a. Which star is in the middle of the diagram? ___________________

b. The star trail is measured to have an angular distance of 120 degrees. How many hours did it take to create this photograph?

From west to east

15°/hour

One time each day (every 24 hours)

To the right

To the left

Polaris

120° ÷ 15°/hour = 8 hours

Coriolis Effect Foucault Pendulum

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Seasons The diagram shows Earth revolving around the Sun. Letters A, B, C, and D represent Earth’s location in its orbit on the first day of the four seasons. First, label the dates of A, B, C, and D on the diagram below. Use this information to help you fill in the table below.

Description Position Description Position

March 21 A 24 hours of darkness at

North Pole D

December 21 D 24 hours of darkness at

South Pole B

September 23 C 24 hours of daylight at North

Pole B

June 21 B 24 hours of daylight at

South Pole D

Winter in N. Hemisphere D Earth is at aphelion B

Summer in N. Hemisphere B Earth is at perihelion D

Spring in N. Hemisphere A Sun is overhead at

Tropic of Capricorn D

Fall in N. Hemisphere C Sun is overhead at

Tropic of Cancer B

Winter in S. Hemisphere B Sun is overhead at Equator A, C

Summer in S. Hemisphere D Earth has greatest orbital

velocity D

Spring in S. Hemisphere C Earth has the lowest orbital

velocity B

Fall in S. Hemisphere A 9 hours of daylight in NY D

Earth is closest to Sun D 15 hours of daylight in NY B

Earth is farthest from Sun B 12 hours of daylight in NY A, C

12/21 6/21

9/23

3/21

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Seasons

The diagram below represents the Earth on the first day of a season as viewed from space. The

shaded area represents nighttime.

1. What is the date represented in the diagram above? ____________________________________

2. What season is beginning on this date in New York State? _______________________________

3. What is the duration of insolation in New York State on this day? __________________________

4. What latitude is receiving the most direct rays of insolation? ______________________________

5. In three months, how will the intensity of insolation change for New York?

6. In six months, how will the duration of insolation for New York compare to the date shown by the

diagram above?

7. The model of Earth provided below represents Earth in its orbit 6 months later. On the model

shown:

A. Draw the position of Earth’s axis and label the axis

B. Label the North Pole

C. Draw the position of Earth’s Equator and label the Equator.

12/21

Winter

23.5°S (Tropic of Capricorn)

In three months (March 21), the intensity of insolation will increase.

NP

Equator

Axis

Over the next six months, the duration of insolation will increase.

9 hours

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Eccentricity

The diagram below represents the orbital path of a planet around the Sun.

1. Calculate the eccentricity of the ellipse above. Show all work. Round your answer to the nearest

thousandth.

2. How does the shape of the orbit above compare to the shape of the orbit of Mercury? __________

______________________________________________________________________________

3. Describe the shape of Earth’s orbit. _________________________________________________

4. How does the gravitational attraction between the planet and Sun change as the planet moves

farther from the Sun? ____________________________________________________________

______________________________________________________________________________

5. How does the orbital velocity change as a planet gets closer to the Sun? ____________________

______________________________________________________________________________

6. On the orbital path above, place an X where the planet’s fastest orbital speed will be.

7. As an ellipse gets more elliptical, what happens to the value of its orbit’s eccentricity? __________

______________________________________________________________________________

______________________________________________________________________________

Sun

e = d = 1.7 cm = 0.2535211 = 0.254

L 6.7 cm

As a planet gets closer to the Sun, the orbital velocity increases (gets faster).

X

As an ellipse gets more elliptical, the value of the orbit’s eccentricity

increases (gets closer to 1).

Slightly eccentric ellipse

As a planet gets farther from the Sun, the gravitational attraction decreases.

Mercury’s orbit is less elliptical than the orbit above.

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Moon Phases The diagram below represents the Moon in 8 positions in its orbit around the Earth.

1. Draw the phase of the Moon, as seen from Earth, for each numbered position in the space above.

2. How long is one revolution of the Moon around Earth? __________________________________

3. How many days does it take for the Moon to complete one complete cycle of phases? _________

4. What causes the phases of the Moon? ______________________________________________

5. Which phase (name and number) causes a solar eclipse? _______________________________

6. Which phase (name and number) causes a lunar eclipse? _______________________________

7. Why do we see the same side of the moon every day? __________________________________

______________________________________________________________________________

8. Describe the height of high tide and low tide of spring tides. ______________________________

______________________________________________________________________________

9. Which two phases (name and number) cause spring tides? ______________________________

10. Describe the height of high tide and low tide of neap tides. _______________________________

______________________________________________________________________________

11. Which two phases (name and number) cause neap tides? _______________________________

12. Why does the Moon have more influence on the tides than the Sun? _______________________

______________________________________________________________________________

13. Approximately how much time is there between consecutive high tides? ____________________

14. Why are there so many more impact craters on the Moon than on Earth? ___________________

_____________________________________________________________________________

Draw the Phase!

1 2 3 4

5 6 7 8

29.5 days

Moon’s revolution around the Earth

New moon (1)

The Moon’s period of revolution equals the Moon’s period of rotation.

Highest high tide & lowest low tide

Lowest high tide & highest low tide

New (1) & Full (5)

1st Quarter (3) & 3rd Quarter (7)

Moon is closer to Earth than Sun.

12 hours 26 min

Earth’s atmosphere has destroyed craters.

Full moon (5)

27.3 days

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New York State Celestial Sphere

The diagram below represents the path of the Sun on different three dates, A, B, and C, as viewed from New York State at 45°N. The position of the Sun is indicated by the circle on each path.

1. Identify one possible date the Sun will travel across each path shown above. Explain your answer.

A: _________________________________________________________________________

B: _________________________________________________________________________

C: _________________________________________________________________________

2. On each path of the Sun, draw two arrows to show the direction the Sun appears to move.

3. Draw and label the position of Polaris on the diagram.

4. State one city in New York State that this observer could be located. ______________________

5. What is the name given to point D? _________________________________________________

6. When is the Sun directly overhead in New York State? _________________________________

7. What time of day is shown by the position of the Sun on each path? _______________________

8. Which season has the greatest angle of insolation? _____________________________________

9. Which season has the lowest angle of insolation? ______________________________________

10. What happens to the length of a shadow from sunrise to noon? ___________________________

11. What happens to the length of a shadow from noon to sunset? ____________________________

12. Which season has the longest noontime shadow? ______________________________________

13. Which season has the shortest noontime shadow? _____________________________________

December 21. Sun rises SE and sets SW.

March 21/September 23. Sun rises due East and sets due West.

June 21. Sun rises NE and sets NW.

Polaris (45°)

Massena

Zenith

Never

Noon (12 pm)

Summer

Winter

Winter

Summer

Gets shorter

Gets longer

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Celestial Spheres from Around the World

The diagrams below show the apparent path and solar noon positions of the Sun on specific dates at three different locations on Earth.

1. Identify the cause of the apparent daily motion of the Sun through the sky. __________________

2. How many hours of daylight is the observer at location C experiencing on June 21? ___________

3. What is the latitude of location C? Explain how you determined this using the diagram. _________

______________________________________________________________________________

4. Explain how you know location A is at the equator. _____________________________________

______________________________________________________________________________

5. How do you know location B is in the Northern Hemisphere? _____________________________

______________________________________________________________________________

Celestial Spheres: Time & Shadows

Locations of the Sun along an apparent path for an observer in NYS on March 21 are shown on the diagram below. Determine the approximate time of day and shadow direction for each location of the Sun. Record your answers in the table below.

Letter Time Shadow Direction

A 9 am Northwest

B 12 pm Due north

C 3 pm Northeast

D 6 pm Due east

Earth’s rotation

24 hours

North Pole – all directions are south

Sun is directly overhead at noon on equinox

Sun is due South at noon each day

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Our Solar System

The diagram below represents a model of our solar system.

1. Does this model represent the geocentric model or heliocentric model? Explain your answer.

_____________________________________________________________________________

_____________________________________________________________________________

2. What is the age of our solar system (including our Sun & all planets)? ______________________

3. Which planets are terrestrial? ______________________________________________________

4. What are the characteristics of these planets? _________________________________________

5. Which planets are Jovian? ________________________________________________________

6. What are the characteristics of these planets? _________________________________________

7. Which planet is most similar in size to Earth? __________________________________________

8. Which planet has a longer day than year? ____________________________________________

9. Which planet would float in water (if you had a container large enough)? ____________________

10. How many times larger is Jupiter than the Earth? ______________________________________

11. Between which two planets is the Asteroid Belt located? ________________________________

12. Why does Venus have the highest surface temperatures, even though it is not the closest planet

to the Sun? ___________________________________________________________________

_____________________________________________________________________________

_____________________________________________________________________________

13. Describe the eccentricity of comets. ________________________________________________

4.6 billion years

Inner 4 – Mercury, Venus, Earth, Mars

Small & rocky

Outer 4 – Jupiter, Saturn, Uranus, Neptune

Large & gaseous

Venus

Venus

Saturn

11 times larger

Mars & Jupiter

Runaway greenhouse effect – Venus’ atmosphere is 95% CO2. This

greenhouse gas allows short-wave visible sunlight to pass through,

but traps long-wave infrared heat near surface.

Comets have very elliptical orbits

Heliocentric model because the Sun is in the center.

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Stars

Diagram A: The diagram below shows the constellation Orion which is visible in the

winter months in the Northern Hemisphere.

Diagram B: The diagram below shows two possible sequences in the life cycles of stars, beginning with

their formation from nebular gas cloud in space.

1. Why can we see Orion in December, but not in June? ___________________________________

2. Fill in the missing information in the chart below using the “Characteristics of Stars” chart.

Star Name Temperature Color Luminosity Star Type

Betelgeuse 3,300 K Orange 100,000 x Supergiant

Procyon B 8,900 K White 0.0007 x White Dwarf

Aldebaran 4,000 K Orange 700 x Giant

Sirius 9,500 K White 30x Main Sequence

3. What is the process by which stars produce energy? ____________________________________

4. What is the “fuel” of the Sun? ______________________________________________________

5. Which category does a majority of the stars fit into? ____________________________________

6. Our Sun is classified in which group of stars? _________________________________________

7. In 5 billion years, our sun will reach its intermediate stage and become a ___________________.

How will the temperature and luminosity change in this intermediate stage? _________________

____________________________________________________________________________

8. What is the ultimate fate of our sun in the late stage? __________________________________

How will the temperature and luminosity change in this late stage? _______________________

____________________________________________________________________________

9. According to Diagram B, what factor determines the life-cycle path of a star? _______________

10. Which force is responsible for changing a nebula into a protostar? ________________________

Earth revolves around the Sun

White dwarf

Temperature will decrease and luminosity will increase.

Temperature will increase and luminosity will decrease.

Mass or size Gravity

Nuclear fusion

Hydrogen

Main sequence

Main sequence

Red giant

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Deep Space & the Origins of Our Universe

Diagram A below represents a timeline of the big bang theory. Diagram B below shows spectral lines of hydrogen gas observed in a laboratory compared to spectral lines of hydrogen gas produced by a distant galaxy.

1. How long ago did the Big Bang occur? ______________________________________________

2. State two pieces of evidence of that support the big bang theory.

1) ____________________________________________________________________________

2) ____________________________________________________________________________

3. Astronomers viewing light from a distant galaxy observe a shift of spectral lines toward the red

end of the visible spectrum. Describe the movement of this galaxy. ________________________

_____________________________________________________________________________

4. Astronomers viewing light from a distant galaxy observe a shift of spectral lines toward the blue

end of the visible spectrum. Describe the movement of this galaxy. ________________________

_____________________________________________________________________________

5. Describe the movement of the galaxy using Diagram B above. Explain your answer. __________

_____________________________________________________________________________

6. What is a galaxy? ______________________________________________________________

7. What is the name of the galaxy we live in? ___________________________________________

8. What type of galaxy do we live in? __________________________________________________

9. How does the age of our universe compare to the age of our solar system? __________________

______________________________________________________________________________

10. List the following astronomical features, in order of relative size, from smallest to largest. Saturn , Milky Way Galaxy, Sun, Universe, Our solar system, Earth’s Moon

Earth’s Moon, Saturn, Sun, Our Solar System, Milky Way Galaxy, Universe

Diagram A Diagram B

Red shift of light from distant galaxies

Cosmic microwave background radiation

Milky Way

Spiral shaped

Our universe is much older than our solar system

13.7 billion years ago

Group of billions of stars

A red shifted galaxy is moving away from the Earth.

A blue shifted galaxy is moving towards the Earth.

This galaxy is moving away from Earth because it is red shifted.

Part 2: Astronomy

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