Big Idea 5 Earth in Space and Time

Florida Next Generation Sunshine State Standards:

SC.5.E.5.1 – Recognize that a galaxy consists of gas, dust, and many stars, including any objects orbiting the stars. Identify our home galaxy as the Milky Way.

SC.5.E.5.3 – Distinguish among the following objects of the Solar System – Sun, planets, moons, asteroids, comets – and identify Earth’s position in it.

SC.4.E.5.4 – Relate that the rotation of Earth (day and night) and apparent movements of the Sun, moon, and stars are connected.

Terms

English Spanish Haitian Creole1. asteroid asteroide astewoyid2. comet cometa komèt3. galaxy galaxia galaxy4. moon luna lalin5. planet planeta planèt

inner planets planetas interiores planèt enteryè outer planets planetas exteriores planèt eksteryè

6. revolution revolución revolisyon7. rotation rotación wotasyon8. solar system sistema solar sistèm solè9. star estrella etwal

Does This Matter to Me?

This picture, courtesy of NASA, our national space program, is an artist's rendering of the planned Space Launch System as a rocket lifts off with the Orion spacecraft atop. The Orion spacecraft is already built and ready at Cape Canaveral in Florida. The Space Shuttle program provided successful low-Earth orbit missions, but NASA's heavy-lift launch vehicle will provide a new capability for human exploration beyond low-Earth orbit. The Space Launch System, shown here with Orion on it, is designed to be flexible for launching spacecraft for crew and cargo missions that will go far beyond to the moon again, to explore asteroids, and even to go to Mars. It will be people who are your age right now, maybe even you, who will be the ones to go on these exciting missions.

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Talk about these questions in your group: How is our view of our Sun different from our view of other stars? How and why does the moon's appearance change over the course of a month? Why do the positions of the moon, stars, and planets change in the night sky?

The Milky Way and Other Galaxies(SC.5.E.5.1)

A galaxy is a system that contains many stars, star systems, dust, and any objects orbiting stars (such as planets). The Milky Way is the name of our galaxy, which is the home of our solar system that includes the Earth and our star, the Sun. The Milky Way is much larger than our solar system and contains many other objects.

Stars are made of gas and give off light energy. Some stars are bigger than others. Some stars are brighter than others.

The Sun

Our Sun is a star of mid-size that emits heat and light energy. There are stars much larger than our Sun, and stars that are smaller. Our star, the Sun, is about 10 times larger than Jupiter, the largest planet in the solar system, and about 109 times larger than Earth. The Sun looks bigger than all of the other stars we can see only because it's closer to us than any other star. To us, it looks like the biggest star in the sky, but other stars may be smaller than, bigger than, or the same size as our Sun. They just look smaller because they are farther away. Let’s compare the diameters of some stars that we can easily see.

Star Name Diameter(in kilometers)

Distance from Earth(in miles)

Distance from Earth(in kilometers)

Sun 1,391,000 93,000,000 149,600,000

Proxima Centauri 201,695 24,698,100,000,000 39,900,000,000,000

Alpha Centauri A(binary star) 1,706,757 25,836,558,515,141 41,551,450,529,369

Barnard’s Star (red dwarf) 208,650 35,273,000,000,000 57,000,000,000,000

Sirius A(binary star) 2,782,000 51,150,350,000,000 82,650,000,000,000

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Which stars are larger than our Sun?

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Explain why these larger stars look so much smaller than our Sun.

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Close Up or Far Away?

Have you ever taken a photograph of a friend? Another way to think about distance and the appearance of size is by thinking about using the zoom function on a camera. The zoom function on a camera can make an object appear to be closer or farther. If you are zoomed into her face, it fills the whole picture. If you are zoomed out, your friend appears smaller.

This is why the Sun looks so large in our sky and the other stars look so small. We are much closer to the Sun than we are to the other stars in the sky.

Most of the stars we see are part of our galaxy. With a telescope we can see other galaxies. There are hundreds of billions of galaxies in the universe and each galaxy might have hundreds of billions of stars, star systems, and planets.

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The universe is so large that it is difficult to imagine. One way to get a sense of the size of the universe is to compare the distances between us and other objects in the universe.

Our Solar System(SC.5.E.5.3)

You may have heard the term solar system, but what does it mean? If you think that it is a system where planets revolve around a sun or star, you are correct. Everything that revolves around the Sun is part of our solar system, including the planets and their moons, the asteroids of the Asteroid Belt, the comets in orbit around the Sun, and dust.

Picture Courtesy of NASA

As you can see in the pictures above, the Asteroid Belt divides our solar system into inner planets and outer planets.

Planets are large bodies in space that orbit a star and do not produce their own light. There are four planets between the Asteroid Belt and the Sun. In order of increasing distance from the Sun are the inner planets – Mercury, Venus, Earth and Mars. Outside the Asteroid Belt are four more planets – Jupiter, Saturn, Uranus, and Neptune. These are called the outer planets.

The four inner planets (Mercury, Venus, Earth, and Mars) are called terrestrial because they resemble the Earth (terra in Latin) and share similar characteristics. They are rocky with similar chemical compositions surrounded by a thin layer of gas (atmosphere). The inner planets are closest to the Sun and closer to each other than the outer planets are.

The four outer planets (Jupiter, Saturn, Uranus, and Neptune) are farther from the Sun and more spread out from one another. They are many times larger than, and are very different from, the inner planets. The outer planets have similar characteristics. They are surrounded by a thick layer of gas (atmosphere) and have many moons orbiting them.

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Although we have not been able to study the insides of the outer planets, it is believed that the center of each planet contains a rocky core. Another characteristic of outer planets is the presence of rings. The rings are formed by rocky and icy material found in space that is trapped by the gravitational pull of the planet.

The sentence: “My Very Educated Mother Just Served Us Noodles” can help you remember the names and order of the planets. Notice that the first letter of each word matches the first letter of each planet, in order from closest to farthest from the Sun. Can you come up with your own phrase to remember the order of the planets?

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Planet Information TablesThe Inner Planets

Name Average Distance from the

Sun (millions

of km)

Size orDiameter

(km)

Time it Takes

to Revolve around the

Sun

Time it Takes to Rotate Once on

Axis

Temperature(°C) (°F)

AtmosphereComposition/

Characteristics

OtherCharacteristics

(Mostly Solid Surface)

Mercury 58 4880 88 days(0.24 Earth

years)

1,407 hours(58 Earth

days)

-170 to 230°C(-274 to 446°F)

The average is 67°C (153°F)

Hydrogen, helium, sodiumVery thin atmosphere with no weather

Rocky, cratered surfaceLooks like the moonLocked rotation causes one side of Mercury to be very hot while the other side is very cold

Venus 108 12,104 225 days(0.62 Earth

years)

5,832 hours(243 Earth

days)

Very consistent

The average is 480°C (896°F)

Carbon dioxide and sulfuric acidThick cloud cover with a strong greenhouse effect

Rocky surfaceVast low areas and high mountains, which may have been active volcanoes.Air pressure is 90 times greater than Earth’s

Earth 150 12,756 365 days(1 Earth

year)

24 hours(1 Earth day)

-90 to 58°C(-130 to 136°F)

The average is 15°C (59°F)

78% Nitrogen, 21% oxygen, <1% carbon dioxide and water vaporGreenhouse effect

1/3 rocky surface2/3 liquid water surfaceModerate temperaturesThe only planet with life as we know it

Mars 228 6794 2 Earth years 24.5 hours(1 Earth day)

-130 to –31°C(-202 to 24°F)The average

is -63°C(-81°F)

Carbon dioxide, nitrogen, argon, oxygen, water vaporThin atmosphere

Rocky surfacePolar icecaps, rust-colored surface, and inactive volcanoesChannels indicate that Mars had rivers

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The Outer PlanetsName Average

Distance from the

Sun (millions

of km)

Size orDiameter

(km)

Time it Takes to Revolve around the Sun

Time it Takes to Rotate

Once on Axis

TemperatureRange

AtmosphereComposition/

Characteristics

OtherCharacteristics

(Mostly Gas Surface)

Jupiter 778 142,700 12 Earth years

10 hours(0.4 Earth

days)

Very cold above clouds to very hot in center

Hydrogen, helium, methane, ammoniaGreat red spot (a huge storm), violent storms

A liquid-hydrogen ocean surfaceOne of its moons has active volcanoes

Saturn 1427 120,000 29 Earth years

10.5 hours(0.4 Earth

days)

Very cold above clouds to very hot in center

Hydrogen, helium, methane, ammoniaViolent storms

Surrounded by a deep layer of metallic hydrogen, an intermediate layer of liquid hydrogen and an outer layer of liquid heliumLacks a definite surfaceMany rings of iceSome scientists think life could evolve on Titan, one of its moons

Uranus 2869 50,800 84 Earth years

16.8 hours(0.7 Earth

days)

Very cold above clouds to very hot in center

Hydrogen, helium, methane

Greenish-blue “ice giant”Core of ice and rock with an unknown surfaceRotates on sideHas a complex series of at least 13 rings of dark particles

Neptune 4486 48,600 165 Earth years

16 hours(0.7 Earth

days)

Very cold above clouds to very hot in center

Hydrogen and helium, methane and ammonia ices

Bluish gas planetRocky core surrounded by an ocean of water, ammonia and methane ices. It has three main rings of ice particles coated with minerals.

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Planet Identification Activity: Types of Planets

In this activity, you will learn the relative sizes of the planets.

Materials: 1 copy of the Relative Sizes of Planets sheet (on the next page) Relative Sizes of Planets Projectable (for the class) Crayons, colored pencils, or markers 1 large piece of yellow or orange construction paper

Procedures:1. Color each of the planets on the Relative Sizes of Planets sheet. Use the

Relative Sizes of Planets Projectable for ideas.2. Draw and cut out a relative full size model of the Sun from yellow or orange

construction paper. Use the quarter Sun on the sheet as a guide. Use crayons to decorate the Sun with flares and flames.

3. Set these colored models aside to use in Inquiry 10.

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In Inquiry 10 below, you will construct a model of the solar system to illustrate the distances of planets from the Sun and from each other.

Inquiry 10: Modeling the Solar System(SC.5.E.5.3)

Inquiry Framework1. Questioning State the problem

How can we model the distances of planets from the Sun and from each other?

Make a predictionIn a model of the solar system, the Sun and Mercury (the closest planet to the Sun) are 14 inches apart. How far do you think it is from the Sun to the farthest planet, Neptune?

120 inches 90 feet 300 feet

2. Planning Read the materials and procedures Do I have all of the necessary materials?

Yes No

Have I read the procedures?Yes No

Summarize the procedures in your own words.

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3. Implementing Gather the materials

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string or yarn meter stick or ruler a long hallway, pavilion, or cafeteria-like room (90 feet or more)

colored planet and Sun models from Planet Identification activity

scissors clear tape

Follow the procedures1. We will use the “Table of Distances” to construct the solar

system model. To make your solar system, unroll some string and place your Sun model at the end of the string.

2. Now use the "Distance between Objects" column to plot the objects of the solar system.

3. Place Mercury 14 inches from the Sun.4. Venus will be 12 inches from Mercury, and Earth will be

10 inches from Venus.5. Continue unrolling strin as needed to plot the locations of

the rest of the objects on the chart.

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Table of Distances

Scale: Three feet equals one Astronomical Unit (AU)

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ObjectSize of Object

(to nearest thousand)

Average Distance

from Sun in Miles/Km

Average Distance

from Sun in

AU

Distance from Sunon String in Inches

Distance between Objects

Sun856,000 mi(1,378,000

km)-- -- --

14 inches

Mercury 3,000 mi(5,000 km)

36 million mi(58 million km)

0.38 14 inches12

inches

Venus 8,000 mi(12,000 km)

67 million mi(108 million km)

0.72 26 inches10

inches

Earth 8,000 mi(13,000 km)

93 million mi(150 million km)

1.00 3.0 feet 1.5 feet

Mars 4,000 mi(7,000 km)

142 million mi(228 million km)

1.52 4.5 feet 11.0 feet

Jupiter 89,000 mi(143,000 km)

483 million mi(778 million km)

5.20 15.5 feet 13.0 feet

Saturn 75,000 mi(120,000 km)

885 million mi(1,426 million

km)9.59 28.5 feet 29.0 feet

Uranus 32,000 mi(51,000 km)

1,787 million mi(2,877 million

km)19.2 57.5 feet 33.3 feet

Neptune 31,000 mi 2,800 million mi(4.508 million 30.1 90.3 feet --

4. Concluding Draw a conclusionWhat did you find out?Compare what you thought would happen with what actually happened. Was your prediction about the distance between the Sun and Neptune supported by this activity?

Yes No

5. Reporting Share your resultsWhat do you want to tell others about the inquiry?Talk with your group members about what you did and what you observed.

Produce a reportRecord what you did so others can learn. Write the answers to the following questions:

1. What did you learn about the distances of the planets from the Sun and from each other?

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2. What did you observe about the distances of the inner planets from the Sun?

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3. What did you observe about the distances of the outer planets from the Sun?

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4. Think about the orbits of the planets around the Sun. If a planet is farther from the Sun, will its orbit be longer or shorter?

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5. Which planet has the shortest year? Which planet has the longest year? Explain your reasoning.

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6. Based on the distances from the Sun, what can you infer about the temperatures of the outer planets?

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6. Inquiry Extension Reflect on your results If I did this inquiry again, how would I improve it? What would be a good follow-up experiment based on

what I learned?

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7. Application Make connections How does this activity relate to what happens in the real

world? How could I apply the results to new situations?

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You have learned the characteristics shared by the inner planets and those shared by the outer planets. Compare and contrast the characteristics of the inner planets with those of the outer planets using the Venn Diagram below.

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Inner Planets Outer Planets

Similarities

Other Space Objects

The Asteroid Belt is located between Mars and Jupiter. Asteroids are objects made up of rock and metal that are too small to be classified as a planet. There is another asteroid belt, much larger than the one between Mars and Jupiter, called the Kuiper Belt, out beyond the orbit of Neptune.

In the outer solar system there are other objects known as comets. The difference between an asteroid and a comet is that while asteroids are made up of rock and metal, comets are mostly made up of frozen gases. As comets come closer to the Sun, their ice begins to melt and creates a “tail” of gas.

The Movement of the Earth around the Sun(SC.4.E.5.4)

Rotation and Revolution of the Earth

When a basketball player spins a basketball on his finger, the ball is rotating. Planets rotate, too. When something rotates, it spins in a direction around an imaginary line we call an axis.

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The illustration to the left shows that the axes of rotation of the planets in our solar system are tilted to various degrees. Notice that the axes are shown by blue lines.© Calvin J. Hamilton

This picture of the rocky asteroid 951 Gaspra was taken by NASA's Galileo spacecraft. Image Credit: NASA

In the case of the Earth, this line runs from the North Pole to the South Pole. The amount of time it takes for the Earth to turn around this axis once is 24 hours or one day. During this spin, half of the Earth is always facing the Sun and half of the Earth is always facing away from the Sun. The part of the Earth facing the Sun experiences day, and the part of the Earth facing away from the Sun experiences night. Even though you are standing still on the Earth, the Earth and you are moving quite a bit.

The Earth is also moving in a big circle around the Sun called an orbit. When one object orbits another object, this is called revolution. The Earth goes around the Sun, or revolves, once every year. One revolution of the Earth takes one year (365¼ days) tocomplete.

When we say that the Earth spins around every day, we can say that the Earth

______________________ on its axis.

When we say that the Earth goes around the Sun every year, we can say that the Earth

______________________ around the Sun.

The rotation and revolution of the Earth are two patterns that contribute to how our world works. Rotation and revolution contribute to things we experience like seasons and day and night. By carefully noticing how things move in the sky, we can learn to understand how the stars, moon, and planets all move through the sky in predictable patterns. We can also see constellations, or groups of stars that form a pattern, and note how they appear and move in the sky. We are observing from our perspective as a result of the Earth’s position, rotation, and revolution. Understanding orbital revolutions helps explain how the Earth travels around the Sun, how the moon travels around the Earth, and how other systems move in the universe.

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Rotation

Revolution

Describe any patterns you have noticed in the night sky.

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Appearance of the Moon

The moon is a dark rock. The moon does not have any light of its own. A person standing on the Earth can only see the moon when sunlight hits the moon and is reflected back to our eyes. It looks like the moon is changing from day to day as the moon goes through phases including the New Moon (where you can’t see the moon) to the Full Moon (where you can see the “whole” face).

Imagine we could stand out in space and look down on the moon as it revolves around the Earth’s equator. We would see that the moon is just like the Earth. Half of its surface is always light because it is facing the Sun. The other half is always dark because it is facing away from the Sun.

Because of our perspective from the Earth, we do not always see the moon as half light and half dark. Some nights we see just the light half (Full Moon). Other nights we see just the dark half (New Moon). Most nights we see something in between. This perspective of what we see from the Earth is shown in the following diagram.

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The Moon as Seen from the Earth

We see the various lunar phases (moon phases) from the Earth because of the relative positions of the Sun, Earth, and moon. For example, during the New Moon phase, the moon is passing between the Earth and the Sun. During the Full Moon phase, the Earth is between the moon and the Sun. From our perspective on the Earth, the moon travels through a predictable series of phases approximately every 28 days.

What views do astronauts have of the Earth and the moon as they orbit the Earth?

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Moon Phases Activity: Modeling the Movement of the Earth and the Moon(SC.4.E.5.4)

In this activity, you will make a model to explain the movement of the Earth and the moon with respect to the Sun.

Materials (per small group): 1 sharp pencil 1 medium Styrofoam™ ball 1 lamp per classroom

Procedures and Observations:1. Push a pencil straight through the center of the Styrofoam™ ball. This represents

the moon on its axis.2. Mark an X on one side of the ball.3. Your teacher will turn on the lamp and darken the room. The lamp represents the

sun.4. One person in your group will stand a few feet from the lamp and represent

Earth. The person who is representing Earth should stand in the center of a circular path and slowly rotate. This person’s rotation represents Earth’s 24 hour cycle. When this person is facing the lamp, it will be noon. When facing the lamp in the opposite direction, it will be midnight.

5. Another person in your group will hold the ball on the stick (moon) a few feet from the student (Earth). The person holding the moon will begin to walk around (revolve) the Earth while spinning the moon on its axis, making sure the X is always facing the student (Earth).Remember: The moon travels in a slightly wobbly path so it is not usually aligned perfectly between the Sun and the Earth. The person holding the moon model should rotate with the moon slightly above the head of the Earth model.

6. You are now modeling the movement of the Earth and the moon by spinning both the Earth and moon and revolving the moon around the Earth.

7. The student who is the Earth should be able to see all of the phases of the moon (ball) as the moon is moving around the Earth. (The “Earth” may stop rotating if it is necessary to note the phases.)

8. Describe the pattern of light and shadow on the moon (ball) and what is observed from the Earth.

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9. Take turns being the Earth, allowing each student in the group to have a chance to get the perspective of standing on Earth and seeing the phases of the moon (repeat steps 6-8).

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In this activity, you modeled the movement of the moon around the Earth. You saw the cause of the phases of the moon. You also observed how the shape of the moon looked different throughout the month.

Star Patterns in the Night Sky

In the dark of night, patterns of stars light up the sky. Patterns of stars are called constellations. Just like the Sun, stars appear to rise from the east, sweep across the night sky, and set in the west. But the Sun and the stars are not actually moving; they just appear to be moving. There are two reasons why stars appear to move across the sky in our solar system. The first reason is because the Earth is spinning on its axis. The second reason is because the Earth is revolving around the Sun. Earth is in constant motion. This is why if you go outside at eight o’clock in the evening and again at eleven o’clock, the stars are in different positions. They seem to have moved toward the west! You get a different view of the stars throughout the night because Earth is rotating on its axis.

If you were to track constellations in the summer sky, they would be different from the constellations you see in the winter sky because of the Earth’s revolution around the Sun. You can also see different constellations depending on what part of the Earth you are viewing the sky from. People in the southern hemisphere (Australia) are able to see some constellations that people in the northern hemisphere (North America) cannot!

Take a look at the images below. Do they look different?

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Stars at 11:00pm

Stars at 8:00pm

Winter SkiesSummer Skies

The stars you see from the Earth in the summer sky look different from the stars you see in the winter sky because the Earth is revolving around the Sun.

Now try this. Stand back to back with a partner. What do you see? Turn clockwise ¼ of a circle. What do you see? Do you see the same things as you did before? Does your partner see the same things as you?

Now, move to another area of the classroom and describe what you see. Do you see the same things from this area of the classroom? Does your partner see the same things as you?

Neither you nor your partner will see the same things at the same time because of your positions. These examples can be related to what happens with the stars in the sky. Depending on the position of Earth as it either rotates on its axis or revolves around the Sun, you see different patterns of stars throughout the year.

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You learned that a galaxy consists of stars, star systems, dust, and any objects orbiting stars (for example, planets). All the stars we see at night from here on Earth are far away, but they are still part of our galaxy, the Milky Way.

The Sun is a star. Stars come in all different sizes and some are brighter than others. Our Sun appears so large and bright in our sky not because it is bigger than all the other stars, but because we are so close to it.

The inner and outer planets of our solar system differ from each other. You discovered the characteristics shared by the inner planets and those shared by the outer planets. Our solar system is not only made up of planets, but also includes objects like asteroids, comets, meteoroids, and dust.

You learned about the movements of the Sun, the Earth, and the moon. The Earth turns, or rotates, on its axis once every day (24 hours). The Earth goes around the Sun, or revolves, once every year. One revolution of the Earth is equal to one year or 365¼ days. The moon rotates on its axis and revolves around the Earth approximately every 28 days. Together these movements help explain why we see the changes in the appearance of the moon at different times of the month.

We observe many patterns from Earth like day and night, changing seasons, and changes in the appearance of the moon. During the night we observe the stars. The stars appear to be moving, but star patterns actually stay the same. The reason why stars appear to move across the sky is because the Earth is spinning on its axis and rotating around the Sun.

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Earth in Space and Time

Assessment

1. Which of these revolves around a planet?

a. An asteroidb. A starc. A cometd. A moon

2. The largest body in our solar system is

a. Earthb. The Sunc. Jupiterd. The Moon

3. Keisha knows that Earth rotates on its axis. What evidence indicates Earth is rotating on its axis?

a. There is a day and a night.b. There are 365 days in each year.c. There are four phases of the moon.d. There are different seasons of the year.

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Use this table for questions 4 and 5.The following table lists several characteristics of each planet in the solar system.

4. What is the connection between the distance from the Sun and the period of revolution?

a. The planets farther from the Sun have longer days.b. The planets farther from the Sun have longer years.c. The planets closer to the Sun have longer days.d. The planets closer to the Sun have longer years.

5. This planet has a year roughly twice as long as an Earth year. Which planet is it?

a. Venusb. Marsc. Jupiterd. Neptune

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6. The solar system consists of inner and outer planets.a. Describe two characteristics of the inner planets.

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b. Describe two characteristics of the outer planets.

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7. What is the name of our galaxy? Name and describe three objects found in our galaxy.

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8. Jacob created a diagram to show some of the common characteristics of planets in our solar system.

Which characteristic should Jacob write in the empty circle of the diagram?

a. Made mostly of gasb. Has a rocky surfacec. Revolves around a stard. Is a satellite of another planet

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