Spectrographs: instrument to separate white light into the bands of color.

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1 (BIG BANG PACKET 2) Name: Period: wavelength and lowest frequencies Broadcast waves and microwaves Infrared Rays Wavelength shorter than radio waves The invisible you feel Visible Light You can see The wavelengths and frequencies appear in the and the wavelengths and frequencies appear in the violet/blue Violet Blue Green Yellow Orange Red Ultraviolet rays Shorter wavelengths and higher frequencies than visible light They carry more than visible light Pros: killing bacteria and providing vitamin D Cons: to much exposure causes skin cancer, can damage your eyes, and burn your skin X-Rays: Shorter wavelengths and higher frequencies than ultraviolet rays, thus can carry more energy Can go most matter, except dense matter like bones Gamma Rays: Have the shortest wavelength and highest frequencies, thus has the amount of energy Great penetrating ability Pros: use to kill cancer cells inside the body, use to help see inside the body Cons: nuclear reactions produce and can be harmful (even deadly if exposed to too much). Spectrographs: instrument to separate white light into the bands of color. This is a spectrum from our sun. The dark lines are where different elements have absorbed different frequencies of light. Each element has its own spectrum, kind of like a finger print. Scientists use spectrographs to determine what elements other stars are made of. Spectral Line Analysis (how it ties to red and blue shift) Because elements have their own spectrum scientist can determine what they are made of. However, stars are on the move with their galaxies. This means that their finger print of where the black lines are will be either shifted toward the red end of the spectrum or the blue end of the spectrum. Activity 1. Which spectrum is that of a star moving toward Earth? 2. Which spectrum is that of a star moving away from Earth? 3. In comparison to A, which is moving faster, B or C? Using data, justify your answer. Hubble s Discovery Just as the light from a single star can be used to make a stellar spectrum, scientists can also use the light given off by an entire galaxy to create the spectrum for that galaxy (Holt 793). In the 1920s, Hubble found that the spectra of galaxies, except a few near our own, where all shift towards the end of the spectrum.

2 By measuring the he was able to determine the speed at which the galaxies were moving from us. Most distance galaxies show the greatest speed and This evidence point to the fact that our universe was. Most galaxies are red-shifted, or moving away from us today. Let s rewind the clock of time. Using the information and data from what you have learned, what can be inferred about the origin of the universe? Continue with Hunting the Edges of Space Part 2 7. What is the Big Bang? 8. What does the radio telescope that Wilson and Penzias used measure? 9. What did Wilson and Penzias discover about the temperature of space away from the Milky Way? 10. Robert Dickie and his colleagues at Princeton University had worked out that the afterglow from the Big Bang should still be felt today. They have even calculated the temperature, what was that temperature? 11. What was the first physical evidence of the Big Bang that was found by Wilson and Penzias? 12. What was W-Map mission? 13. On the W-MAP picture, what do the red dots mean? 14. What is the age of the universe? 15. What was the importance of putting telescope above the Earth s atmosphere? 16. How are telescopes time machines? 17. What name have scientists given to the force that is causing our universe to expanding faster today than it was in the past? 18. What percent of the universe still needs to be revealed?

3 You will be reading an article about the big bang theory. The article can either be found in the folder in the classroom or from the link below. Read the article and then summarize the three pieces of evidences that supports the theory. Also include a definition or a summary of what is the big bang theory. Link: Big Bang Theory: Evidence 1: Evidence 2: Evidence 3: Notes on the Big Bang: Studies of of distant galaxies show that the universe is expanding. The Big Bang Theory claims that the universe has expanded from a very dense, very hot state that existed at some time in the past. Running the expansion backward allows us to calculate the and density of the universe during its earliest moments. The known laws of physics can be used to determine the behavior of matter and energy at these temperatures and densities. The model is then used to make predictions that can be compared to observations. Big Bang Timeline: About a millionth of a second o Temperature is about K (ten trillion Kelvin) a lot of energy o Protons, anti-protons, neutrons and anti-neutrons begin to form o As a proton or neutron collides with its anti-particle they annihilate and are converted to in the form of

4 o Because of the large amount of energy available, as fast as these particles annihilate, new protons, antiprotons, neutrons and anti-neutrons form o A billion and one protons and neutrons form for every billion anti-protons and anti-neutrons About one ten-thousandth of a second... o Temperature has fallen to about K (one trillion Kelvin) o It is no longer enough to produce protons and anti-protons (or neutrons and anti-neutrons) spontaneously from pure to replace those that annihilate each other. o Almost all particles and anti-particles annihilate and produce gamma ray photons. o Annihilation results in a billion photons for every proton or neutron o are constantly scattered by free particles with an electric charge like electrons or protons o These photons in as the universe and will eventually become the majority of photons that make up the o Immediately after annihilation there are numbers of protons and neutrons o High energy collisions between protons, neutrons and other particles like electrons can transform one particle into another. o These constantly occurring reactions that transform protons and neutrons into each other initially maintain equal numbers of protons and neutrons... p + + e n + e n + e + p + + e o... however, the mass of a proton is slightly less than the mass of a neutron, so... About a tenth of a second... As the temperature (and available energy) drops, transformation to protons is favored over neutrons About one second o Transformation reactions can no longer occur. Neutrons begin to decay into protons n p + + e + e About 100 Seconds o Temperature is about 10 9 K. Neutron decay results in a 1:7 abundance of neutrons to protons at this point. o Universe is now cool enough for protons and neutrons to bind together. This is called. o This process creates new, heavier atomic nuclei and is called nucleosynthesis. About 10 minutes...the end of big bang nucleosynthesis

5 o After the temperature drops below about 10 9 K (one billion Kelvin), very little happened in nucleosynthesis for a long time as temperature and density are too low for fusion. o It required star formation for the production of elements. About 380,000 years o Temperature drops to 3000 K o Universe is cool enough for electrons to bind with nuclei and form atoms o With most electrons now bound in atoms, photons can travel large distances without being scattered by free electrons. Photons now travel in all directions, resulting in what is called the cosmic background radiation. Now o With continued expansion, temperature drops to about (Three degrees above absolute zero) o Photons that make up the cosmic background radiation are now most of these photons were produced by the particle anti-particle annihilation at about one tenthousandth of a second Big Bang Model Predictions o The only elements in the early universe were and (and a tiny amount of lithium). The hydrogen-helium mass ratio was about 75-25%. o Microwaves with an energy corresponding to a temperature of about 3 K will be found everywhere in space. From Earth they will be seen across the entire sky. Goal: how most of the elements from the periodic table were formed We learned from the reading that Hydrogen and Helium were the first element to form after the big bang. But where did all the other elements form? To understand this we must first look at the formation of stars. Follow the links below to a website about star formation and an assignment to complete. Website Link: (website works best in Google Chrome) Star Formation Notes/Worksheet The Website works best in Google Chrome. Website: If this website doesn t work then go to my blog and click on the astronomy category. Then click on the posting that says website: star formation. 1. What is a nebula? 2. What elements makeup a nebula? 3. What cause a nebula to contract? 4. Equilibrium must be achieved for a protostar to become a star. What are the two forces that must be balanced? 5. Summarize the 6 steps that explain the battle between the two forces.

6 6. After step six there are two possible routes a protostar will take. What are they? 7. What is a star? 8. Click on the Interactive Lab titled beginning of their life cycles. What patterns do you see? Is there a difference in how long it stays on the main sequence depending on size? What about when the stars enter the main sequence is there a pattern there? 9. Which hypothesis is correct, the first or second one? 1. The bigger a star is, the longer it will live 2. The smaller a star is, the longer it will live 10. What is the star s main goal in life? 11. What is the 5-step process that a stars goes through while living its life on the main sequence? 12. Click on the interactive lab titled Equilibrium Cycle. Follow the instructions and then circle where the pressure, gravity, and temperature are for the 5 steps. Steps Pressure Gravity Temperature 1 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 2 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 3 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 4 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 5 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 13. Test you know with the practice quiz. There are 8 questions. You have to answer the 1st 4 and then after you check your answers there will be a next button to answer the next 4 questions How long it takes for a star to die depends upon what? 15. How does a lower-mass star die? 16. How does a high mass (massive) star die? 17. Take part one of the star quiz. There are 6 questions

7 18. Click on the interactive lab titled helium burning process. Follow the instructions and then circle where the pressure, gravity, and temperature are for the 5 steps. Steps Pressure Gravity Temperature 1 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 2 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 3 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 4 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 5 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 19. Is there a similarity to the hydrogen process? 20. What is the difference between the hydrogen and helium fusion process? (hint: the answer is in the paragraph below the link to the interactive lab) 21. Take Star Quiz part 2. There are only two questions In the core Helium is fusing into carbon, but fusion is still happening in the outer parts of the star where Hydrogen is fusing into Helium. During this phase in a star s life the star will increase in size because of the rapid heat generated by the hydrogen and Helium fusion in the core and outer shell of the star. By clicking on the red giant link (colored yellow) find out these two questions: 1. How big will our sun expand to? 2. Red Giants are large in size, but are they massive? 23. What are the three categories of stars? Include their mass and what they will become. You will have to come back to this question to write down what massive stars become. 24. Click on the interactive lab titled Carbon Burning Process. Follow the instructions and then circle where the pressure, gravity, and temperature are for the 5 steps. Steps Pressure Gravity Temperature 1 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 2 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 3 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 4 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 5 UP CONSTANT DOWN UP CONSTANT DOWN UP CONSTANT DOWN 25. When carbon burning does occur what element is formed? 26. Review how different mass of stars end their life by viewing the interactive lab titled end of their life cycles. Initial here when you have done this. 27. What two things do the Hertzsprung-Russell (HR) Diagram measure? 28. After reading the information about the HR diagram click on the interactive lab, this is the picture. Complete the table. Star Temperature Brightness A B C D E

8 29. Once you are done with the HR diagram interactive lab click the next page and then click it again until you come to the page titled Interactive HR Diagrams. Next click on the interactive lab picture to see how luminosity and temperature changes for a medium mass star. Once you have viewed it initial here:. 30. For extra credit you can test your knowledge about the HR Diagram. Click on the last picture under the header More HR diagram Fun, and answer the questions (it might only let you take 14 of the questions) End questions of Formation of Heavy elements: 1. What to forces are always battling against each other? 2. What must happen before fusion can begin? 3. Which of the following most accurately explains the origin of heavy elements on Earth? a. Formed by nuclear reactions in massive, ancient stars b. Formed by radioactive decay deep within Earth's core c. Formed by black holes scattered throughout the galaxy d. Formed by comets and asteroids falling to the Earth 4. What is the relationship between the mass of a star and the relative mass of elements produced? a. As more massive stars are examined, temperature and pressure are seen to be greater, and heavier elements are produced b. As more massive stars are examined, temperature and pressure are seen to be less, and lighter elements are produced c. As less massive stars are examined, temperature and pressure are seen to be greater, and lighter elements are produced d. As less massive stars are examined, temperature and pressure are seen to be less, and heavier elements are produced