Presentation is loading. Please wait.

Presentation is loading. Please wait.

LESSON 13: Origins of the Universe PPT Modified from 63310/Stars,_Galaxies,_and_the_Universe.ppt#256,1,Stars,%20Gal.

Similar presentations


Presentation on theme: "LESSON 13: Origins of the Universe PPT Modified from 63310/Stars,_Galaxies,_and_the_Universe.ppt#256,1,Stars,%20Gal."— Presentation transcript:

1 LESSON 13: Origins of the Universe PPT Modified from /Stars,_Galaxies,_and_the_Universe.ppt#256,1,Stars,%20Gal axies,%20and%20the%20Universe PPT Modified from /Stars,_Galaxies,_and_the_Universe.ppt#256,1,Stars,%20Gal axies,%20and%20the%20Universe

2 Lesson 13: Section 1 History of the Universe The galaxies in the universe are like the raisins in rising bread. The raisins move away from each other as the bread rises. The galaxies in the universe are like the raisins in rising bread. The raisins move away from each other as the bread rises. The universe is getting bigger all the time. The universe is getting bigger all the time.

3 Big Bang Theory The initial explosion that resulted in the formation and expansion of the universe. The initial explosion that resulted in the formation and expansion of the universe. The universe was small, hot, and dense. It exploded about 10 to 15 billion years ago to make our universe. The universe was small, hot, and dense. It exploded about 10 to 15 billion years ago to make our universe.

4 Formation of the Solar System After the big bang, matter in the universe separated into galaxies. Gas and dust spread throughout space in our galaxy. About 5 billion years ago, a giant cloud of gas and dust, or nebula, collapsed to form the solar system. After the big bang, matter in the universe separated into galaxies. Gas and dust spread throughout space in our galaxy. About 5 billion years ago, a giant cloud of gas and dust, or nebula, collapsed to form the solar system. Nebula shrank to form a disk = the sun was born. Nebula shrank to form a disk = the sun was born. The spheres closest to the sun lost most of their gases and became the inner planets. The spheres closest to the sun lost most of their gases and became the inner planets. The spheres farthest from the sun became the gas giants or the outer planets. The spheres farthest from the sun became the gas giants or the outer planets.

5 Lesson 13: Section 2 Star Systems and Galaxies

6 Star Systems and Planets Our solar system has only one star, the sun. Our solar system has only one star, the sun. More than half of all stars are members of groups of two or more stars, called star systems. More than half of all stars are members of groups of two or more stars, called star systems.

7 Review What was the Big Bang? What was the Big Bang? A giant explosion in which all the matter in the universe began moving apart. A giant explosion in which all the matter in the universe began moving apart. Describe how the solar system formed. Describe how the solar system formed. The solar system formed out of a collapsing, spinning disk of gas and dust. The center of the disk formed the sun. Matter toward the edge formed the planets, asteroids, and a cloud of ice and other substances. The solar system formed out of a collapsing, spinning disk of gas and dust. The center of the disk formed the sun. Matter toward the edge formed the planets, asteroids, and a cloud of ice and other substances. What observations show that the universe is expanding? What observations show that the universe is expanding? The galaxies are all moving away from each other. The farther away a galaxy is away from the Milky Way, the faster it moves away, because there is more space. The galaxies are all moving away from each other. The farther away a galaxy is away from the Milky Way, the faster it moves away, because there is more space.

8 Galaxies 3 Main Galaxies: Spiral Galaxies, Elliptical Galaxies 3 Main Galaxies: Spiral Galaxies, Elliptical Galaxies Irregular Galaxies Spiral: A galaxy that has the shape of twin spirals. Elliptical: Look like flatten balls. Irregular: Do not have a regular shape.

9 Review What is a star system? What is a star system? A star system is a group of two or more stars. A star system is a group of two or more stars. Describe the 3 main types of galaxies. Describe the 3 main types of galaxies. Spiral galaxies are shaped like twin spirals, with arms that spiral out like pinwheels. Elliptical galaxies look like flattened balls. Irregular galaxies do not have regular shapes. Spiral galaxies are shaped like twin spirals, with arms that spiral out like pinwheels. Elliptical galaxies look like flattened balls. Irregular galaxies do not have regular shapes. Where is the sun in our galaxy? Where is the sun in our galaxy? The sun is about 25,000 light-years away from the center of the galaxy, about 2/3 of the way out in one of the spiral arms. The sun is about 25,000 light-years away from the center of the galaxy, about 2/3 of the way out in one of the spiral arms.

10 Lesson 13: Section 3 Characteristics of Stars

11 Terms Characteristics of Stars Galaxy: Contains hundreds of billions of stars. (Milky Way) Galaxy: Contains hundreds of billions of stars. (Milky Way) Universe: All of space and everything in it. Universe: All of space and everything in it. Light-year: Distance that light travels in one year. It is a unit of distance not time. Light-year: Distance that light travels in one year. It is a unit of distance not time.

12 Classifying Stars The main characteristics used to classify stars are: Size, Temperature and Brightness. The main characteristics used to classify stars are: Size, Temperature and Brightness. Star sizes largest to smallest are: Star sizes largest to smallest are: Super Giant, Giant, Medium, White Dwarf, and Neutron stars. Super Giant, Giant, Medium, White Dwarf, and Neutron stars.

13 Color and Temperature of Stars A stars color reveals its temperature. The coolest stars are red and hottest stars are blue, blue-white. A stars color reveals its temperature. The coolest stars are red and hottest stars are blue, blue-white. The brightness of a star depends upon its size and temperature. The brightness of a star depends upon its size and temperature. How bright a star looks from Earth depends on both how far the star is from Earth and how bright the star actually is. How bright a star looks from Earth depends on both how far the star is from Earth and how bright the star actually is.

14 Brightness Apparent magnitude: Is the stars brightness as seen from Earth. (use electronic devices to measure it. Apparent magnitude: Is the stars brightness as seen from Earth. (use electronic devices to measure it. Absolute magnitude: A brightness a star would have if it were a standard distance from Earth. Absolute magnitude: A brightness a star would have if it were a standard distance from Earth.

15 Hertzsprung-Russell Diagram A graph used by astronomers that shows the relationship between surface temperature and brightness of stars. A graph used by astronomers that shows the relationship between surface temperature and brightness of stars. Most stars (90%) fall under the Main Sequence in which surface temperatures increases as brightness increases. Most stars (90%) fall under the Main Sequence in which surface temperatures increases as brightness increases.

16 Review List three characteristics used to classify stars. List three characteristics used to classify stars. Size, temperature (or color) and brightness Size, temperature (or color) and brightness Which is hotter-- a red star or a blue star? Why? Blue stars are hotter than red stars because gas glows red at lower temperatures and blue at higher temperatures. Blue stars are hotter than red stars because gas glows red at lower temperatures and blue at higher temperatures.

17 Lesson 13: Section 4 Lives of Stars

18 A Star Is Born Nebula: All stars start out as nebulas. A large amount of gas and dust spread out in an immense volume. Nebula: All stars start out as nebulas. A large amount of gas and dust spread out in an immense volume. Proto: Greek for earliest Proto: Greek for earliest Protostar: Earliest stage of a star. Protostar: Earliest stage of a star. A star is born when the contrasting gas and dust become so hot that nuclear fusion starts. A star is born when the contrasting gas and dust become so hot that nuclear fusion starts. How long a star lives depends on how much mass it has. (More mass=shorter lives) How long a star lives depends on how much mass it has. (More mass=shorter lives)

19 Death of Stars When a star runs out of fuel, it becomes a white dwarf, a neutron star, or a black hole. When a star runs out of fuel, it becomes a white dwarf, a neutron star, or a black hole. When it runs out of fuel the center of the star shrinks and the outer part of the star expands. When it runs out of fuel the center of the star shrinks and the outer part of the star expands.

20 Terms of Stars White dwarf: The remaining hot core of a star after its outer layers have expanded and drifted out into space. White dwarf: The remaining hot core of a star after its outer layers have expanded and drifted out into space. Neutron Star: A tiny star that remains after a supernova explosion. Neutron Star: A tiny star that remains after a supernova explosion. Supernova: The explosion of a dying giant or supergiant star. Supernova: The explosion of a dying giant or supergiant star. Black hole: The remains of an extremely massive star pulled into a small volume by the force of gravity. Black hole: The remains of an extremely massive star pulled into a small volume by the force of gravity.

21 Review What is the earliest stage in the life of a star? What is the earliest stage in the life of a star? The star begins as part of a nebula. A cloud of dust and gas. Some of the dust and gas condenses to form a protostar. Nuclear fusion begins and the protostar becomes a star. The star begins as part of a nebula. A cloud of dust and gas. Some of the dust and gas condenses to form a protostar. Nuclear fusion begins and the protostar becomes a star. Why do small-mass stars have longer lifetimes than large-mass stars? Why do small-mass stars have longer lifetimes than large-mass stars? Small-mass stars burn their fuel more slowly than large- mass stars. Small-mass stars burn their fuel more slowly than large- mass stars.

22 Review continued What is the difference between stars that become white dwarfs and stars that become neutron stars? What is the difference between stars that become white dwarfs and stars that become neutron stars? Giant stars collapse into neutron stars. Smaller stars form white dwarfs. Giant stars collapse into neutron stars. Smaller stars form white dwarfs. What evidence do astronomers use to detect black holes? What evidence do astronomers use to detect black holes? Scientist detect black holes by observing radiation from hot gas near the black hole, and by studying the effect of the black holes gravity on a nearby star. Scientist detect black holes by observing radiation from hot gas near the black hole, and by studying the effect of the black holes gravity on a nearby star.

23 Lesson 13: Stars, Galaxies, and the Universe Section 5

24 Tools of Modern Astronomy Constellations: Patterns of stars in the sky. Constellations: Patterns of stars in the sky.

25 Electromagnetic Radiation Visible light: Light you see with your eyes. Visible light: Light you see with your eyes. Electromagnetic radiation: Energy that can travel directly through space in the form of waves. Electromagnetic radiation: Energy that can travel directly through space in the form of waves.

26 Electromagnetic Spectrum Wavelength: The distance between the crest of one wave and the crest of the next wave. Wavelength: The distance between the crest of one wave and the crest of the next wave. Spectrum: light that spreads out to make a range of different colors with different wavelengths. Spectrum: light that spreads out to make a range of different colors with different wavelengths. Electromagnetic spectrum: includes radio waves, infrared radiation, visible light, ultraviolet radiation, X- rays, and gamma rays. Electromagnetic spectrum: includes radio waves, infrared radiation, visible light, ultraviolet radiation, X- rays, and gamma rays.

27 Telescopes Telescopes: Collect and focus different types of electromagnetic radiation including visible light. Telescopes: Collect and focus different types of electromagnetic radiation including visible light. Observatory: A building that contains one or more telescopes. Observatory: A building that contains one or more telescopes.

28 Spectrographs Spectrograph: Breaks the light from an object into colors and photographs the resulting spectrum. Spectrograph: Breaks the light from an object into colors and photographs the resulting spectrum. Astronomers use spectrographs to get information about stars, including their chemical compositions and temperatures. Astronomers use spectrographs to get information about stars, including their chemical compositions and temperatures.

29 Chemical Composition and Temperature of Stars Chemical elements in a stars atmosphere absorb light from the star. Each element absorbs light at different wavelengths. Thus by comparing them to other known spectrums of different elements astronomers can infer which elements are found in a star. Chemical elements in a stars atmosphere absorb light from the star. Each element absorbs light at different wavelengths. Thus by comparing them to other known spectrums of different elements astronomers can infer which elements are found in a star. Chemical composition of stars are about 73% hydrogen,25% helium, and 2% other elements. By comparing a stars spectrum with the known spectrums of elements at different temperatures, astronomers can infer how hot the star is. Chemical composition of stars are about 73% hydrogen,25% helium, and 2% other elements. By comparing a stars spectrum with the known spectrums of elements at different temperatures, astronomers can infer how hot the star is.

30 Review For what purpose are telescopes designed? Telescopes collect and focus electromagnet radiation. What can astronomers tell from looking at a stars spectrum? Astronomers can determine the chemical composition and the temperature of the star.


Download ppt "LESSON 13: Origins of the Universe PPT Modified from 63310/Stars,_Galaxies,_and_the_Universe.ppt#256,1,Stars,%20Gal."

Similar presentations


Ads by Google