2. STRAND #1 – EARLY ASTRONOMY 1. Name the scientist that said the sun was the center of the solar system (and not the Earth) AND name the scientist that studied the planetary motion of the planets. Copernicus is the scientist that said the sun was the center of the solar system. Johannes Kepler studied the planetary motion of the planets.

3. 2. Define prograde and retrograde rotation. Prograde rotation is counterclockwise and retrograde rotation is clockwise.

4. 3. What two factors affect the gravitational attraction between two objects? The two factors that affect the gravitational attraction between two objects is Mass and Distance.

5. 4. As two objects come CLOSER (less distance) together, will the gravitational force between them increase or decrease? Increase

6. 5. As the mass of two objects increases, will the gravitational force between them increase or decrease? Increase

7. 6. According to Kepler’s Second Law of Motion, will a planet move faster or slower when it nears the sun? According to Kepler’s Second Law of Motion, the closer a planet gets to the sun, the faster it will move.

8. 7. What is the Earth's period of revolution and period of rotation? Earth’s period of revolution is 365.25 days. Earth’s period of rotation is 24 hours.

9. 8. Compare and Contrast between an orbit, revolution, ellipse, and rotation. An orbit is the elliptical path described by one celestial body in its revolution around another. Revolution is the movement of one object around another. Rotation is when an object in space spins on its axis.

10. STRAND #2 – THE STARS 9. Describe the life cycle of a star (use terms like white dwarf, main sequence, red giant, supernova, etc) 1 st - Stellar Nebula: Cloud of dust and gas. 2 nd - Main Sequence: Star is in the prime of its life. You can tell its temperature by looking at its color. 3 rd - Red Giant: Is a start that expands and cools once it loses all of its hydrogen. 4 th - Supernova: Is the death of a large star by explosion. 5 th - White Dwarf: Is the left over center of a star that has used up all of its hydrogen.

11. Star Life Cycle

12. 10. Explain how the temperature of a star is classified. Scientist can tell the temperature of a star by looking at its color (yellow – mild temperature star, blue – hot star)

13. 11. Define nuclear fusion. Where in a star does nuclear fusion occur? Nuclear fusion is when two hydrogen nuclei fuse together to create helium. Nuclear fusion occurs in the core of a star.

14. STAND #3 – THE FAMILY OF PLANETS 12. How do the inner planets differ from the outer planets? The inner planets are Terrestrial planets, which are dense, rocky bodies. Inner planets are also smaller in size than outer planets. The outer planets are Jovian planets (or Gas Giants), which are large, gas bodies. Gas giants also have larger atmospheres.

15. 13. What are the four largest planets in our solar system, in order of largest to smallest? The four largest planets are Jupiter, Saturn, Uranus, and Neptune.

16. 14. What group does Earth belong to and why? (Terrestrial or Jovian) Earth belongs to the Terrestrial planets (and inner planets)

17. 15. Why do scientists think that Pluto is NOT a gas giant? Scientists do not consider Pluto to be a gas giant, because it is a small, dense dwarf planet. Pluto is composed of rocks and ice.

18. 16. What does Astronomical Unit stand for? Astronomical Unit (AU) stands for distance from the Earth to the Sun. 1 AU is approximately 150 million kilometers.

19. STRAND #4 – THE MOON AND OTHER SMALL BODIES IN SPACE 17. What causes the phases of the moon? The phases of the moon are caused by sunlight being reflected from the moon’s surface. The moons phase is dependent on the relative position of the moon, earth, and sun.

20. 18. Why do we always see the same side of the moon? We also see the same side of the moon because its period of revolution (around the earth) is 27.5 days and its period of rotation (around its axis) is also 27.5 days.

21. 19. What happens during a total solar eclipse? What happens during a lunar eclipse? A solar eclipse is when the moon moves between the sun and the earth. A lunar eclipse is when the earth moves between the sun and the moon.

22. 20. Why don’t we see solar and lunar eclipses every month? We do not have a solar or lunar eclipse every month because the sun, earth, and moon do not line-up perfectly and because the moon’s orbit is tilted.

23. 21. Define satellite, meteorite, meteor, comet, asteroid, and asteroid belt. A satellite is a small, celestial body that revolves around a planet (another name for a moon). A meteorite is a meteoroid that has hit the Earth’s crust. A meteor is a meteoroid that is burning up in the Earth’s atmosphere (shooting star) A comet is a dirty snowball, composed of rock, ice, and cosmic dust. The asteroid belt is a region between Mars and Jupiter where many asteroids and celestial bodies are located.

24. Label the planets on this diagram. 1.Mercury 2. Venus 3. Earth 4. Mars 5. Jupiter6. Saturn7. Uranus8. Neptune (no #9)

25. Name the phases of the moon.