THE SUNTHE SUN

The sun is but a morning star.The sun is but a morning star.- Henry David Thoreau- Henry David Thoreau

By: Kristen SingletonBy: Kristen Singleton

Science Standard 3: Science Standard 3: The Physical SettingThe Physical Setting

Indicator 3.3.3- Observe and describe that the sun can be seen only in the daytime.

Taken from: http://dc.doe.in.gov/Standards/Academic

Standards/StandardSearch.aspx Link to Activity:

http://www.indianastandardsresources.or g/files/sci/sci_3_3_where%20the%20sun%20 goes.pdf Additional Indicators: 3.1.3, 3.1.4, 3.3.1, & 3.6.4

DefinitionsDefinitions

Sun- the star that is the source of light and heat for the planets in the solar system

Daytime- the time after sunrise and before sunset while it is light outside

Nighttime- the time after sunset and before sunrise while it is dark outside

Rotation- the act of turning, as a wheel or a solid body on its axis

NASA- (National Aeronautics and Space Administration)An independent agency of the United States government responsible for space flight and aviation

Background InformationBackground Information The Earth’s distance from the sun is 93 million

miles. The sun is 4.5 billion years old. Much like the Earth the sun has many different

layers that define its structure. Unlike the Earth, the sun is completely gaseous,

there is no solid surface on the sun. The sun rotates on its axis about once every 26

days The middle of the sun is at least ten million

degrees. The sun is mainly hydrogen and helium.

Unlike the planets, the sun is a great big sphere of hydrogen gas. Because of this, different parts of the sun rotate at different speeds. You can see how fast the surface is rotating by tracking the movement of sunspots across the surface. Regions at the equator take 25 days to complete one rotation, while features at the poles can take 36 days and the inside of the sun seems to take about 27 days.

Watch Video Clip: http://starchild.gsfc.nasa.gov/Videos/StarChild

/solar_system/suna.avi

BackgroundBackground Information Information

As the World Turns…As the World Turns…Gather around the globe. Identify the country you live in. Then identify the state that you live in. Label that state with highlighter tape. Turn off the lights. The darkness of the room represents the darkness of thesky that surrounds the Earth. The light from the flashlight represents the sun. Shine the flashlight on the globe, with the light pointing at the globe. If the light is shining on your state, “Is it daytime or nighttime?”

As the World Turns…As the World Turns…Slowly turn the globe with out moving the flashlight. Examine how the sunlight falls on different areas of the Earth at different times. Watch for the moment that your state is opposite of the light. “Is it daytime or nighttime? Is there sunlight shining on the state we live in? Can we see the sun at night?”

The Sun Mark…The Sun Mark…Answer the following: Is the sun always in the same place in the sky? Does the sun seem to be moving?Think about the flashlight and globe

demonstration. Did the flashlight move? Did the light always shine on the same part of

the globe? Explain how the light position changed while the

flashlight stayed in the same spot.This is the Earth’s rotation which causes the sun to

appear to rise and set.

Go outside at 9 a.m. with your sun journal and stand at the sun stick.

Remember to not look directly at the sun for it is dangerous and harmful on your eyes.

Pick up the rock that is labeled 9 a.m. and place it where the shadow of the stick falls.

The shadow is being marked to show the Earth’s movements.

Record the shadow positions in your science journal.

Return to the sun stick at 12 noon and 2 p.m. Mark the shadow of the stick each time with

the correct rock and time.

The Sun Mark…The Sun Mark…

Observe the movement of the shadow as the sun appears to change position in the sky.

After you have made three observations, make sure you have written about them in your journal.

Participate in discussion with the rest of the class what you have learned and observed.

The Sun Mark…The Sun Mark…

Take a look at TechnologyTake a look at Technology

Look at the NASA Web site http://earth.jsc.nasa.gov/ to see how the sun is actually illuminating the Earth at this particular time of observation.

Connecting the Curriculum Connecting the Curriculum Write poetry about the night sky or about the

brilliance of the sun on a sunny day.

Our star, the Sun is a big ball of gasAnd it's 99 percent of our solar system's mass It's an average star in our Milky Way Warming the Earth every day

What powers our Sun and makes it so bright? Come on and tell me, what makes all that light? Hans Bethe long ago reached the conclusionIt changes Hydrogen to Helium by nuclear fusion

When fusion takes place light is createdAnd it makes its way out (although rather belated)Through the Photosphere that's the part that we see The light comes out and shines on you and me

About a million Earths could fit in the SunBut if you were there you wouldn't have much fun It's six thousand degrees at the photosphere And much hotter inside the solar atmosphere

Connecting the Curriculum Connecting the Curriculum

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CLASSCLASS

AssessmentAssessment Does the sun

move in the sky?A. YesB. No

How do you know?A. There is a daytime

and a nighttime.B. There is a moon.C. The Earth rotates

around the sun.D. It has its own axis.

During what part of the day can you see the sun?A. MorningB. NoonC. NightD. Both A and B

Are there other people in the world who can see the sun when it is not visible to you?A. YesB. No

AssessmentAssessment