1 / 24

Stars

Stars. Chapter 13 Section 1 Pgs. 370 - 374. Constellations. Patterns of stars Represented mythological characters, animals, or familiar objects Spots of light made into a shape Stars found at specific locations in constellations 88 total As Earth orbits Sun they appear then disappear.

alexa
Télécharger la présentation

Stars

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Stars Chapter 13 Section 1 Pgs. 370 - 374

  2. Constellations • Patterns of stars • Represented mythological characters, animals, or familiar objects • Spots of light made into a shape • Stars found at specific locations in constellations • 88 total • As Earth orbits Sun they appear then disappear

  3. Star Light • Absolute Magnitude – light a star gives off • Apparent Magnitude – amount of light received from a star on Earth • If close to Earth a star appears brighter even if its dim • A star that is dim from a far away distance would be bright

  4. Measurement in Space • Light-year – distance light travels in one year • Light travels at 300,000 km/s or 9.5 trillion km per year • Nearest star – Proxima Centauri (4.3 light-years away)

  5. Properties of Stars • Color = temperature • Hot = blue-white • Cool = orange or red • Sun = yellow

  6. Questions • What do constellations represent? • How many constellations are in the modern sky? • What is absolute magnitude? • What is apparent magnitude? • What is a light-year? How many km/s? How many km/year? • What is the name of the nearest star? • How do you know the temperature of a star? • What color means hot? What means cool?

  7. The SunSection 2Pgs. 375 - 378

  8. The Sun’s Layers • Center of the solar system • Closest star to earth • Enormous ball of gas, produces energy by fusing hydrogen into helium • Figure 6 Page 375 • Core: Hydrogen fusion • Radiation zone: Energy travels outward • Convection zone: Gases ciruculate, swirls

  9. The Sun’s Atmosphere • Photosphere: Lowest layer, light given off, Temp is 6000K • Chromosphere: 2000Km above photosphere, • Corona: largest layer, extends millions of km into space, temps as high as 2 million K. • Charged particles travel into space from the corona as solar wind.

  10. Surface Features • Sunspots: Areas that are cooler than surrounding areas, • Sunspots showed that the sun rotates; faster at the equator than at the poles. They appear and disappear. • Prominences: huge arching columns of gas. • Solar Flares: Gases near sunspot brighten suddenly shooting outward at high speed.

  11. Surface Features • CMEs (Coronal mass ejections): Large amounts of electrically charged gas are ejected from the corona. • Damage satellites in orbit around earth. • Interfere with radio. • Energy particles from CMEs are carried in the solar wind, and cause the aurora when they enter earths atmosphere.

  12. The Sun-An Average Star • Middle aged • Absolute magnitude is average • Yellow light • Light reaches earth in 8 minutes • Not close to any other stars. • Most systems have at least 2 stars orbiting each other (binary system).

  13. Questions • How does the sun produce energy? • Describe the radiation and convection zones of the sun. • What is the corona? • What are sunspots? • What are prominences and solar flares? • What does CME stand for? How do they affect us on earth? • Why is the sun an average star?

  14. Evolution of StarsSection 3Pgs. 380 - 385

  15. Classifying Stars • Vary in age, size, temperature, brightness • Hertzsprung-Russel Diagram – shows relationship between temperature and absolute magnitude • Main sequence – hot, blue, bright stars in upper left and cool, red, dim stars in lower right. • Sun – in between main sequence • As stars die, move off main sequence

  16. Dwarfs and Giants • 90% are main sequence stars • White dwarfs – hot, not bright • Red giants – extremely bright, not hot, usually red in color • Super giants – largest giants

  17. Star Energy • Einstein: E = mc² (mass turned into energy) • M = mass • C = speed of light • E = energy • Small amount of mass lost when H fuses to form He and converts to large amount of energy • Fusion occurs in the core

  18. Evolution of Stars • Sun – life span of 10 billion years • Nebula – stars begin as large cloud of gas and dust, gravity causes cloud to break apart to form stars • Smaller pieces move together and temp increases • Fusion begins • Energy releases ball of gas into space forming stars

  19. Life Cycle – Giants • Late stage in life cycle • H is lost • Core contracts, temp in core increases • Outer layer expands and cools

  20. White Dwarf • Core used most He • Contracts more and outer layers escapes • Hot, dense core • Size of Earth • Cools and stops giving off light

  21. Supergiants • Core heats up higher • Heavier and heavier elements from fusion • Core collapses violently • Shock wave travels outward producing a supernova, million times brighter than original star

  22. Neutron Stars • Collapsed core of supernova • 1.4 – 3 times bigger than Sun • Small, dense core

  23. Black Holes • More than 3 times mass of Sun • Core collapses to a point • Gravity so strong nothing can escape, not even light

  24. Questions • What is Hertzsprung-Russel Diagram? • What % of stars are found in the main sequence? • What is a nebula? • What age is our sun? • What is the latest stage in a stars life? • What is a super giant? • Why can light not escape a black hole?

More Related