3/24/14 Mass & Weight

1. 3/24/14 Mass & Weight Warm up questions: Periods 1 & 3 Would you weight more on Earth or on the Moon? What factors do you have to consider when figuring out your weight at these two locations? 5

2. 3/24/14 Mass & Weight Warm up question: Periods 5,6 & 7 1. Would you weight more on Earth or on the Moon? Why do you think this? *Remember to pick up your warm up question sheet* *Found to the left of the promethean board* 5

3. Go over upcoming project Complete handout and turn in Homework if not complete 4

4. Do we need to diet on Mars? What would you weigh if you lived on Mars? Is there a difference between mass and weight? These questions and others will be answered as students are introduced to the concept of gravity as it applies to astronomy, and determine what their weight and mass would be on other planets. 3

5. All objects, living and non-living, have both mass and weight. Mass: is a measure of the amount of ‘stuff’ that makes up objects. Weight: is a measure of how much that ‘stuff’ is pulled by gravity. Mass does not change from planet to planet. Weight does change from planet to planet – depending upon the relative gravity 2

6. Worksheet: Determine your mass on Earth and then on each planet in our solar system in kilograms. Homework: Finish and turn in worksheet 1

7. 3/25/14 Gravity Warm up questions: Period 1 & 3 How would living on a planet with more gravity than Earth affect you? What about a planet with less gravity?

8. 3/25/14 Gravity Warm up questions: Period 5,6 & 7 How would living on a planet with more gravity than Earth affect you? What about a planet with less gravity?

9. 1. Bill Nye video on gravity.2. Remaining class time is to be spent answering the questions on pages

10. 3-26-14 Characteristics of Stars Warm up questions: Period 1 & 3 1. Do you know the name of a constellation? 2. Do you know how we classify stars? 11

11. 3-26-14 Characteristics of Stars Warm up question: Period 5, 6 & 7 1. Do you know how we classify stars? 11

12. Constellation: an imaginary pattern of stars in the sky. Astronomers classify stars according to their physical characteristics. 10

13. The physical characteristics are: Color Temperature Size Composition Brightness 9

14. Color and Temperature: These let us know how hot the surface temperature is on a star. The coolest stars appear reddish in the sky and have surface temperatures of around 3,200 degrees Celsius. The hottest stars appear bluish and have surface temperatures over 20,000 degrees Celsius. 8

15. Hottest Coolest 7

16. Size: We’re so far away from them that they all look to be the same size but this is not accurate. Giant/Supergiant stars: are larger than our sun. White dwarf stars: are much smaller than our sun. Neutron stars: are even smaller. About 20 kilometers in diameter. 6

17. Chemical Composition: Stars vary in their chemical composition. Most stars have a chemical composition made up of: 73% hydrogen 25% helium 2% other elements by mass 5

18. Do you know what a spectrograph is? Spectrograph: a device that breaks light into colors and produces an image of the resulting spectrum. 4

19. When you look at a star’s light through a spectrograph, each absorbed wavelength is shown as a dark line on a spectrum.Each chemical element absorbs light at a particular wavelength. 3

20. Brightness of a star: Depends upon both its size and temperature. Apparent Brightness: is its brightness as seen from Earth. Absolute Brightness: is the brightness the star would have if it were at a standard distance from Earth. You must first find the star’s apparent brightness and its distance from Earth before you can calculate the absolute brightness. 2

21. Homework: Read pages: 752-758 Due question #1 a,b and c on page 759. 1

22. 3/27/14 The Lives and Deaths of Stars Warm up questions: Period 1 & 3 1. The length of a star’s life is dependant upon how much what it has? (what is it’s fuel?) 2. Does a star just fade out when it runs out of fuel? 9

23. 3/27/14 The Lives and Deaths of Stars Warm up question: Period 5,6 & 7 1. The length of a star’s life is dependant upon how much what it has? (what is it’s fuel?) 9

24. Lives of Stars: Believe it or not, stars do not last forever. They have cycles just like humans. They are born, live and die. (no, they are not really alive – just a comparison) 8

25. All stars start their lives as parts of a nebulas. Nebulas: is a large cloud of gas and dust spread out in an immense volume. Gravity pulls gas and dust together in the densest part. Prostar: a contracting cloud of gas and dust with enough mass to form a star. A star is formed when a nebula gets hot and dense enough for nuclear fusion to start. 7

26. Nuclear fusion: the process by which atoms combine to form heavier atoms. A star’s life expectancy depends upon its mass. * Stars with less mass lasts longer than a star with more mass. 6

27. Death of Stars: When a star runs out of fuel it will become: 1. a white dwarf 2. a neutron star 3. a black hole 5

28. 1. White dwarf: the blue-white hot core of a star that is left behind after its outer layers have expanded and drifted out into space. They are made from low-mass and medium-mass stars. They are only about the size of the Earth, but they have as much mass as the Sun. 4

29. Supernova: the brilliant explosion of a dying supergiant star. They are made from high-mass stars. Some of the left over material may become part of a nebula. Thus starting the cycle over again. 3

30. 2. Neutron stars: the small, dense remains of a high-mass star after a supernova. They are even smaller and denser than a white dwarf. 2

31. 3. Black hole: an object whose gravity is so strong that nothing, not even light, can escape. These are made from the most massive stars. After a very massive star dies in a supernova explosion, more than five times the mass of the sun may be left. The gravity of this mass is so strong that it shrinks inward. Homework: Read pages 762-766. 1

32. 3/28/14 Star Systems and Galaxies Warm up questions: Period 1 &3 1.What type of a galaxy is the Milky Way? 2. What mathematical form do astronomers use to write very large numbers? 8

33. 3/28/14 Star Systems and Galaxies Warm up question: Period 5, 6 & 7 1. What type of galaxy is the Milky Way? 8

34. The sun is the only star in our solar system. Most stars are members of groups of two or more stars, called star systems. Binary stars: Star systems that have two stars. Eclipsing binaries: A system in which one star periodically blocks the light from another star. 7

35. Galaxies: Galaxy: is a huge group of single stars, star systems, star clusters, dust and gas bound together by gravity. The largest galaxies have more than a trillion stars! Astronomers classify most galaxies into the following types: 1. Spiral 2. Elliptical 3. Irregular 6

36. Spiral Galaxies: appear to have a bulge in the middle and arms that spiral outward. Most new stars are found in the spiral arms. 5

37. Elliptical Galaxies: look like round or flattened balls. These galaxies contain billions of stars but have little gas and dust between the stars. 4

38. Irregular Galaxies: are typically smaller and do not have regular shapes. Theyhave many bright, young stars and lots of gas and dust to form new stars. 3

39. The Milky Way: Is a spiral galaxy. 2

40. The Scale of the Universe: The universe is so large that astronomers often use scientific notation to describe sizes and distances. Universe: all of space and everything in it. Scientific notation: mathematical method of writing numbers using powers of ten. 1

41. Change in Project Date!!!! Since a number of students don’t have access to the internet. I am trying to figure out how to give you some class time to do your research.