1. Our Universe

2. Universe
TEKS
8.8 A: DESCRIBE components of the universe including stars, nebulae and galaxies, and use models as the Hertzsprung-Russell diagram for classification.

3. All space and the matter space contains
Universe
All space and the matter space contains
The Big Bang Theory is one theory of the formation of the Universe. It states that the universe began with a tremendous explosion

4. Universe
contains:
Galaxies
Stars
Nebulae
Quasars
Comets

5. Galaxies There are four main types of Galaxies Spiral Elliptical
Irregular
Lenticular

6. Galaxies Spiral Characterized by a bulge at the center and spiral arms
Spiral shape is caused by the rotation of the galaxy

7. Galaxies
Elliptical
Characterized by a very bright centers and very little dust and gas
Appear elongated or spherical and are basically massive blobs of stars
Composed of mostly old stars

8. Galaxies Irregular Galaxies that do not fit into any other class
As their name indicates they have irregular shapes

9. Galaxies
Lenticular
Galaxies with a central bulge or bar with short arms, if any are present

10. Stars
Composition
Brightness
Temperature
Mass
Life Cycle

11. Stars Composition Made up of different elements in the form of gasses
When viewed through a spectrograph the specific gasses can be identified through an absorption spectrum which is a continuous spectrum with dark lines where less light gets through.

12. Stars Illustrating the relationship between temperature and brightness

13. Stars Mass Single most important determiner of a stars life cycle
High Mass
Low Mass

14. Stars Illustrating the relationship between mass and star life time – smaller stars have longer lives!

15. Illustrating the relationship between mass and brightness
Stars
Illustrating the relationship between mass and brightness

16. Nebula Latin for “Cloud” Giant clouds of gas and dust
Where new stars are formed
Found in spiral galaxies
Not found in elliptical galaxies

17. Quasars The most powerful energy source in the universe
May be the core of young galaxies forming
Among the most distant objects in space from Earth

18. Comets http://www.nasa.gov/audience/forkids/home/F_SC_comet.html
A comet is made of dirty ice, dust, and gas.
When a comet gets close to the Sun, part of the ice starts to melt. This lets the dust and gas out.
Solar winds then push them away from the comet. This makes the comet's tail.
Every time a comet comes close to the Sun, a part of it melts. Over time, it will completely disappear.
A comet does not give off any light of its own. Ice in the comet acts just like a mirror. What we see is sunlight bouncing off the comet.

19. Comets
Halebopp Comet

20. Looking through the center of the Milky Way

21. Questions and Discussion
1. Which characteristics are used to classify stars?
A. temperature
B. brightness (magnitude)
C. mass
D. All of the above

22. Questions and Discussion
1. Which characteristics are used to classify stars?
A. temperature
B. brightness (magnitude)
C. mass
D. All of the above

23. Questions and Discussion
1. Temperature and brightness are both used to classify stars as seen on the HR diagram, but mass is also important because it determines a stars temperature and brightness.

24. Questions and Discussion
2. If a star becomes a black hole at the end of its life, it is a?
A. high mass star
B. nebula
C. low mass star
D. All of the above

25. Questions and Discussion
2. If a star becomes a black hole at the end of its life, it is a?
A. high mass star
B. nebula
C. low mass star
D. All of the above

26. Questions and Discussion
2. Becoming a black hole would mean that the star was a high mass star, giant actually as seen in the following illustration.

27. Questions and Discussion
3. Galaxies are classified based on their?
A. composition
B. color
C. shape
D. All of the above

28. Questions and Discussion
3. Galaxies are classified based on their?
A. composition
B. color
C. shape
D. All of the above

29. Questions and Discussion
3. Galaxies are classified based on their shape. This is evident because of their name categories. The categories of galaxies are spiral, elliptical and irregular.

30. Questions and Discussion
4. Scientist believe that quasars give off as much light as 10 trillion suns because of their?
A. composition
B. distance and brightness
C. shape
D. color

31. Questions and Discussion
4. Scientist believe that quasars give off as much light as 10 trillion suns because of their?
A. name
B. distance and brightness
C. shape
D. color

32. Questions and Discussion
4. Scientist know the absolute brightness of a quasar known as PKS , and they know that it gives off as much light as 10 trillion suns because of its calculated distance using parallax.