tcapreview

1. tcapreview by: Adrian Pettigrew

2. Spiral galaxies • Spiral Galaxy - these galaxies are relatively flat and have a bulge in the middle. These galaxies have arms that spiral out from the center. Our Milky Way galaxy is a spiral galaxy, and the Sun, our closest star, is one of the stars in it. Below is a picture of the spiral galaxy M81.

3. Barred spiral galaxies • Barred Spiral Galaxy - these galaxies are shaped like spiral galaxies, except for the fact that the arms begin spiraling out from a straight line of stars instead of from the center. Below is a picture of the barred spiral galaxy NGC 1672.

4. Elliptical Galaxy - • these galaxies look like a round or flattened ball and contain little gas and dust between the stars. These are often described as taking on the shape of a football. Below is a picture of the elliptical galaxy NGC 1132

5. Irregular galaxies • Irregular Galaxy - these galaxies have no discernible shape or structure. Below is a picture of the irregular galaxy I Zwicky 18.

6. Planetary nebulas • A nebula (plural = nebulae) is a cloud of dust and gas that exists in space, usually between stars. Nebulae can generally be classified into two categories based on their size and shape—planetary nebulae and diffuse nebulae. • A planetary nebula is a relatively small, ball-shaped nebula that surrounds a star. The nebula forms from material ejected from the star's outer layers as the star begins to collapse. The Hubble Space Telescope image below shows a planetary nebula.

7. diffuse nebula • A diffuse nebula is a larger nebula with an irregular shape. Diffuse nebulae located near stars reflect starlight or give off their own bright light. The image below shows a diffuse nebula.

8. ""Spiral Nebulae" • The term "spiral nebulae" was used by astronomers before the 20th century. This term referred to a class of spiral-shaped objects believed at that time to be nebulae in our own Milky Way Galaxy. Modern astronomers now know that these objects are actually spiral galaxies located far beyond the Milky Way.

9. star clusters • A star cluster is a group of stars bound to each other by gravity. Star clusters can be classified into two general categories—galactic clusters and globular clusters. A galactic cluster is an open cluster of stars that are loosely bound to each other by gravity. A globular cluster is a spherical cluster of stars that are tightly bound to each other by gravity. The images below show an example of each cluster type.

10. GLOBULAR CLUSTAR • THIS IS A DIFFERRENT TYPE OF STAR CLUSTER

11. SOLAR SYSTEM AND MILKY WAY • Our solar system is located in the Milky Way Galaxy. The Milky Way Galaxy is a spiral galaxy that contains hundreds of billions of stars. In fact, in areas on Earth without excessive light pollution, the stars of the Milky Way create a band of light that can be seen in the night sky. The entire Milky Way Galaxy is about 100,000 light years across.

12. The sun • The Sun is a medium-sized star within the Milky Way Galaxy. The Sun and our solar system are about halfway out from the center of the Milky Way Galaxy. The entire Milky Way Galaxy is about 100,000 light years across.

13. comets Comets have the most elliptical orbits of all the objects in the solar system. They move into the inner solar system for only a short amount of time. Once they have passed around the Sun, they move back out into the outer reaches of the solar system again, often well past Pluto, and are not seen again for many years.

14. asteroids • The majority of the asteroids in our solar system can be found in the space between Mars and Jupiter. This area is called the asteroid belt. Asteroids vary greatly in size and shape and are mostly there are 4 main classifications of asteroids: • 1. Carbon (C-type) • 2. Silicate (S-type) • 3. Metallic (M-type) • 4. Dark (D-type)

15. meteorites • Meteorites are only found on the surface of planets. The reason for this is that until they survive the trip through the atmosphere of a planet and actually land on the planet's surface, they are classified as meteoroids. Most meteorites are created as the result of collisions of asteroids, comets, moons, and even planets within our solar system. • Classifying meteorites has proven to be a difficult thing because they are usually formed when smaller chunks of material are knocked off of larger objects. Meteorites have come from asteroids, comets, moons, and even planets. The 3 main classifications of meteorites are stony, stony iron, and iron.

16. Identify a testable topic • A testable question is one that can be answered by performing an investigation. Questions about opinions and emotions generally do not make good testable questions for experiments, although some information can be gathered about opinions by performing a survey.

17. Research the topic • Before an investigation can go any further, some basic research about the topic must be done. Research can include making observations about things in nature, asking an expert, or looking in books and on the Internet.

18. 3. Form a hypothesis • A hypothesis is a possible answer to a scientific question and is based on gathered information. In science, a hypothesis must be testable. This means that it must be possible to carry out the investigation and to gather evidence that will either support or disprove the hypothesis.

19. 4. Design an experiment to test the hypothesis • An experiment must be designed to test the hypothesis. All factors that can change in an experiment are called variables. The manipulated (independent) variable is the one factor that is changed by the person doing the experiment. The responding (dependent) variable is the result of changing the manipulated variable. A fair test is an experiment or comparison in which only one variable is changed or tested.

20. 5. Collect the data • A controlled experiment produces data. Data are things, such as facts and measurements, that are gathered by making observations during the experiment. • Observations involve the senses of sight, hearing, touch, and smell. Often, scientists use tools, like microscopes, that increase the power of their senses or make their observations more precise. • Data can be recorded by writing or drawing in a notebook. Data can also be recorded by using computers, cameras, videotapes, and other tools. Using tables to record data can help organize observations neatly.

21. 6. Interpret the Data • When an experiment is finished, the data from the experiment should be analyzed. Organizing data in tables, charts, and graphs makes it easier to see patterns and any relationship of one variable to another.

22. 7. Explain Results • After gathering and interpreting data, conclusions should be made about what happened when the manipulated variable was changed.

23. 8. Compare results to the hypothesis • The results of the experiment should be compared to the original hypothesis. Do the results support the hypothesis? Do they disprove the hypothesis? Hypotheses should not be thought of as right or wrong. Something is usually learned from the experiment, even if the results are not what was expected.

24. 9. Communicate the findings • The results, analysis, and agreement (or disagreement) of the findings with the original hypothesis should be communicated to others. Communicating results helps people learn from one another.

25. The end • The end