A Solar System Is Born Section 1 Science Journal Entry Could astronauts land on a star in the same way that they landed on the moon? Explain why or why

A Solar System Is BornSection 1

Science Journal Entry

Could astronauts land on a star in the same way that they landed on the moon? Explain why or why not. Write your answer in your science journal.

Copyright © by Holt, Rinehart and Winston. All rights reserved.

http://www.google.com/imgres?imgurl=http://static.flickr.com/101/285102672_4203221326.jpg%3Fv%3D0&imgrefurl=http://www.flickr.com/groups/lightpollution/discuss/72057594090820425/&usg=__j_OA5Kf6pV5_Ek-m1Mic4gLj7s0=&h=375&w=500&sz=219&hl=en&start=3&sig2=CvTxA-7h8quLiwhn9qzKdg&zoom=1&itbs=1&tbnid=Wmv9cAjhZDXKzM:&tbnh=98&tbnw=130&prev=/images%3Fq%3Dlight%2Bpollution%2Bpictures%26hl%3Den%26gbv%3D2%26tbs%3Disch:1&ei=8PMhTbqtB4ep8Abj2JHODQ

http://www.google.com/imgres?imgurl=http://todaysfacilitymanager.com/facilityblog/wp-content/uploads/hk_pollution1.jpg&imgrefurl=http://todaysfacilitymanager.com/facilityblog/labels/light_pollution&usg=__Cu-csNnQfLbjChz57QXZ-CkTqW8=&h=768&w=1024&sz=81&hl=en&start=4&sig2=HSFz-omcqr4KQaEesd6YZQ&zoom=1&itbs=1&tbnid=kSTK_A5g77m7AM:&tbnh=113&tbnw=150&prev=/images%3Fq%3Dlight%2Bpollution%2Bpictures%26hl%3Den%26gbv%3D2%26tbs%3Disch:1&ei=8PMhTbqtB4ep8Abj2JHODQ

http://www.google.com/imgres?imgurl=http://www.pha.jhu.edu/~atolea/second/IDAusa_lights_small.gif&imgrefurl=http://www.pha.jhu.edu/~atolea/second/page2.html&usg=__W5ANBUXwEU4BziIALgf950WJWRI=&h=480&w=800&sz=32&hl=en&start=7&sig2=XRsXAzw5JZ24zcAv_Z1K8g&zoom=1&itbs=1&tbnid=RciuzW1NzcNKiM:&tbnh=86&tbnw=143&prev=/images%3Fq%3Dlight%2Bpollution%2Bpictures%26hl%3Den%26gbv%3D2%26tbs%3Disch:1&ei=8PMhTbqtB4ep8Abj2JHODQ

Questions For thought today

• What is Light Pollution?

• What are Nebulas?

• What determined if a planet was going to be a gas giant or rocky (terrestrial)?

• What does terrestrial mean?

A Solar System Is BornSection 1


End of Slide

Section 1 The Solar Nebula• What Are Nebulas? Nebulas (or nebulae) are mixtures of gases—mainly hydrogen and helium—and dust made of elements such as carbon and iron.

• Gravity Pulls Matter Together The matter of a nebula is held together by the force of gravity.

• Pressure Pushes Matter Apart In a nebula, outward pressure balances the inward gravitational pull and keeps the cloud from collapsing.


End of Slide

Section 1 Upsetting the Balance

• Cosmic Collision The balance between gravity and pressure in a nebula can be upset if two nebulas collide or a nearby star explodes.

• What Is a Solar Nebula? The solar nebula— the cloud of gas and dust that formed our solar system— may have formed in this way.


End of Slide

Section 1 How the Solar System Formed• From Planetesimals to Planets As bits of dust circled the center of the solar nebula, some collided and stuck together to form golf ball-sized bodies.

• Gas Giant or Rocky Planet? The largest planetesimals formed near the outside of the rotating solar disk, where hydrogen and helium were abundant. Therefore, the outside planets are gas giants while the inner planets are rocky.

• The Birth of a Star As the planets were forming, nearly all of the extra matter in the solar nebula was traveling toward the center where the star forms.


End of Slide

Answers to Questions of the day.

• What is Light Pollution?

• What are Nebulas?

• What determined if a planet was going to be a gas giant or rocky (terrestrial)?

• What does terrestrial mean?

The Sun: Our Very Own StarSection 2


Sun spots are cool spots on the surface of the Sun that appear black. Would it be possible to land on a Sun spot? Why or why not?


The Sun: Our Very Own StarSection 2

The Structure of the Sun


• Surface of the Sun Although the sun may appear to have a solid surface, it does not.

End of Slide

Section 2



• Burning or Shrinking? It is clear to scientists that the sun does not burn its fuel. In the past, scientists began to think that gravity was causing the sun to slowly shrink.

• Nuclear Fusion Nuclear fusion is the process by which two or more low-mass nuclei join together, or fuse, to form a more massive nucleus. Nuclear fusion occurs in the sun.

• Fusion in the Sun In the center of the sun, the temperature and pressure are very high. As a result, the hydrogen nuclei have enough energy to overcome the repulsive force, and hydrogen fuses into helium.

End of Slide

Fusion of Hydrogen in the Sunhttp://www.youtube.com/watch?v=0TzIJz4_kYI&feature=related

Section 2


Section 2Solar Activity


• Sunspots Sunspots are cooler, dark spots of the photosphere of the sun.http://video.google.com/videosearch?q=Solar+Granulation&hl=en&emb=0&aq=f#

• Climate Confusion Scientists have found that sunspot activity can affect the Earth’s climate.•http://www.youtube.com/watch?v=x6RYgQ2jxCU

•Solar Flares Solar flares are regions of extremely high temperature and brightness that develop on the sun’s surface.

End of Slide

The Earth Takes ShapeSection 3


The Earth is approximately 4.6 billion years old. The first fossil evidence of life on Earth has been dated to nearly 3.5 billion years ago.

Write a paragraph in your science journal describing what Earth might have been like during the first billion years of its existence.



Formation of the Solid Earth

• The Effects of Gravity As the Earth grew to this size, the rock at its center was crushed by gravity and the planet started to become round.

• The Effects of Heat As the Earth was changing shape, it was also heating up. The heat causes the core of Earth to melt.


End of Slide


How the Earth’s Layers Formed

• Organized by Density As rocks melted on the forming Earth, denser elements, such as nickel and iron, sank to the center of the Earth and formed the core. Less dense elements floated to the surface and became the crust. This process is shown on the next slide.


End of Slide

The Formation of the Earth’s LayersSection 3



Formation of the Earth’s Atmosphere

• Earth’s First Atmosphere Scientists think that Earth’s first atmosphere was a mixture of gases that were released as Earth cooled.

• Earth’s Second Atmosphere As the Earth cooled and its layers formed, the Earth’s second atmosphere was able to form. This atmosphere probably formed from volcanic gases.


End of Slide


The Role of Life

• Ultraviolet Radiation Scientists think that ultraviolet (UV) radiation, the same radiation that causes sunburns, helped produce the conditions necessary for life.

• The Source of Oxygen Photosynthetic organisms played a major role in changing Earth’s atmosphere to become the mixture of gases, including oxygen, that you breathe today.


End of Slide


Formation of Oceans and Continents

• Oceans From Rainfall Scientists think that the oceans probably formed during Earth’s second atmosphere, when the Earth was cool enough for rain to fall and remain on the surface.

• The Growth of Continents The continents over time thickened and slowly rose above the surface of the ocean.


End of Slide

Planetary MotionSection 4


What is the difference between rotation and revolution?



A Revolution in Astronomy

• Kepler’s First Law of Motion The planets move around the sun in an ellipse.

• Kepler’s Second Law of Motion the planets seemed to move faster when they are close to the sun and slower when they are farther away.

• Kepler’s Third Law of Motion Planets further from the sun, such as Saturn, take longer to orbit the sun.


End of Slide

Earth’s Rotation and RevolutionSection 4


An EllipseSection 4



Newton to the Rescue!

• The Law of Universal Gravitation Newton’s law of universal gravitation states that the force of gravity depends on the product of the masses of the objects divided by the square of the distance between the objects.

• Orbits Falling Down and Around Gravity keeps the moon from flying off in a straight path. The next slide shows gravity’s effect on the motion of the moon.


End of Slide

Gravity and the Motion of the MoonSection 4


Formation of the Solar SystemChapter 20

Concept Map


Use the following terms to complete the concept map on the next slide: spectra, absolute magnitude, brightness, color, temperature, spectrograph, stars, emission lines.

Concept MapChapter 20


Concept MapChapter 20


Documents

A Solar System Is Born Section 1 Science Journal Entry Could astronauts land on a star in the same way that they landed on the moon? Explain why or why