* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download Miss Nevoral - Ms. Nevoral`s site
Extraterrestrial life wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Perseus (constellation) wikipedia , lookup
Dark matter wikipedia , lookup
Spitzer Space Telescope wikipedia , lookup
Shape of the universe wikipedia , lookup
International Ultraviolet Explorer wikipedia , lookup
Fermi paradox wikipedia , lookup
Space Interferometry Mission wikipedia , lookup
Dark energy wikipedia , lookup
Gamma-ray burst wikipedia , lookup
Wilkinson Microwave Anisotropy Probe wikipedia , lookup
Fine-tuned Universe wikipedia , lookup
Ultimate fate of the universe wikipedia , lookup
Corvus (constellation) wikipedia , lookup
Expansion of the universe wikipedia , lookup
Outer space wikipedia , lookup
Andromeda Galaxy wikipedia , lookup
Flatness problem wikipedia , lookup
Cosmic distance ladder wikipedia , lookup
Modified Newtonian dynamics wikipedia , lookup
High-velocity cloud wikipedia , lookup
Star formation wikipedia , lookup
Cosmic microwave background wikipedia , lookup
Observational astronomy wikipedia , lookup
Physical cosmology wikipedia , lookup
Non-standard cosmology wikipedia , lookup
H II region wikipedia , lookup
Observable universe wikipedia , lookup
Miss Nevoral Science 9 Space Unit http://www.sd23.bc.ca/~lnevoral Chapter 10 – Evidence that Universe Formed 13.7 Billion Years Ago KEY Name: _____________________ Date: ____________ Block: ________ Section 10.1 – Explaining the Early Universe (pages 346 – 355) 1. Define astronomers: People who study space and objects in space. 2. Explain why scientific theories are not considered the final truth/fact about something. Theories are developed with existing information. The main ideas about a theory may change if new evidence arises or there is a breakthrough with technology, etc. Therefore, we can not say that a theory is a fact because more evidence may be found to change that theory. 3. Define celestial bodies: General term for all objects in the sky Sun, moon, planets, and stars. 4. The development of the telescope allowed astronomers to see more celestial bodies. 5. Who was the first astronomer to identify other galaxies besides the Milky Way? What did he notice about the direction of movement of galaxies in space? What conclusion did he make when he observed this direction of movement? Edwin Hubble was the first astronomer to identify other galaxies. He noticed that galaxies appeared to be moving away from each other and that the universe was expanding. He discovered this by using a tool known as red shift analysis. 6. Draw and explain what Figure 10.1 on page 346 is trying to represent in the box below. The figure is trying to show that galaxies are moving away from Earth and that galaxies farther away are moving faster than galaxies closer to ours. 1 7. Define electromagnetic radiation: Energy that is carried in the form of waves. 8. Name four types of electromagnetic radiation. Radio waves, microwaves, infrared radiation, visible light, UV radiation, X-rays, gamma rays. 9. What is a spectrum? Explain the use of a spectroscope. White light splits into a pattern of colours and this is called a spectrum. A spectroscope separates light into its basic components. It allows the user to view the spectral lines produced by stars and galaxies and to measure their wavelengths. 10. What does the cosmological red shift suggest about the motion of galaxies? The cosmological red shift suggests that galaxies are moving away from each other. 11. Who first proposed the Big Bang Theory and in what year? Georges Lemaitre first proposed the Big Bang Theory in 1927. 12. State the main idea of the Big Bang Theory. The theory suggests that 13.7 billion years ago a tiny volume of space with high mass suddenly and rapidly expanded to immense size. In a very short time, all the matter and energy in the universe was formed. 13. According to the Big Bang Theory, how did the temperature of the universe change as the universe expanded? The universe cooled as it expanded. 14. What does COBE and WMAP stand for? COBE Cosmic Background Explorer; WMAP Wilkinson Microwave Anistropy Probe 15. Both the COBE satellite and WMAP were designed to measure temperatures only a few degrees above absolute zero. Why was it necessary to take these measurements in space rather than from Earth? The Earth’s atmosphere is warm, making detection of extremely low temperatures (like those found in space) very difficult. 16. How does cosmic background radiation provide evidence for the Big Bang theory of the origin of the universe? Cosmic background radiation is leftover radiation from the initial explosive expansion of the universe which would support the idea of the Big Bang theory. 17. Why is cosmic background radiation important in the study of the information of galaxies? Dark areas of WMAP indicate dense areas of the early universe. 2 Astronomers hypothesize that these patches show where galaxies were formed. Section 10.2 – Galaxies (pages 356 – 363) 1. Define galaxies: An enormous collection of gases, dust, and billions of stars held together by gravity. 2. What is the name of our galaxy? What shape is our galaxy? Our galaxy is the Milky Way. It is a spiral galaxy. 3. What is a nebula and what is the difference between it and a galaxy? A nebula is a cloud of gas and dust in space. It is different from a galaxy because a nebula is where stars are born and a galaxy is a large collection of stars. 4. What galaxy is our nearest neighbouring galaxy? Andromeda 5. Identify the type of galaxy shown in each sketch. Write your answer beneath each one. 1. Spiral 2. Spiral from its side 3. Elliptical 4. Irregular 3 6. What characteristics do all galaxies share? Galaxies are large, contain stars, spinning. 7. How does the speed at which a galaxy rotates affect its shape? The more spin a galaxy has, the flatter it will be. 8. Besides shape, what other ways do galaxies differ from each other? Galaxies differ in size, mass, brightness, colour, and speed of spin. 9. Describe the two different types of star clusters galaxies may contain. Globular cluster as many a 1 million stars, held together by their mutual gravity in a spherical shape. Open cluster only a few hundred to a few tens of thousands of stars. 10. What is “galactic cannibalism”? When galaxies get too close, the gravitational force of a larger galaxy can pull apart a smaller galaxy. Eventually, the big galaxy will pull the pieces of the smaller galaxy into its own structure. 11. How do the millions or billions of stars of a galaxy stay together? Gravity 12. Image that an astronomer is observing a group of three galaxies. If the spectrum of each of the galaxies is shifted towards the blue end, what can the astronomer conclude about the galaxies? That the galaxies were moving towards each other (shorter wavelengths). 13. List the following in order of size, from smallest to largest: universe nebula galaxy star Star, nebula, galaxy, universe 4