1. CHAPTER 30
Basics of Astronomy

2. Basic Vocabulary
Calendars…a means of keeping track of all the days in a year
Mayans (2000 BC) and Chinese (1300 BC) were the first to calculate the correct length of a year ( days)

3. The Lunar Cycle
The phases occur because of the different positions of the Earth, Moon and Sun
Orbit is the path the moon moves around the Earth…it orbits in a counterclockwise direction (same direction that the Earth orbits the sun.
New moon: moon is between Earth and Sun (cycle takes 29.5 days to complete)
Full moon: moon is on the opposite side of Earth and Sun

4. Moon Phases

5. Days / Months / Years
Axis: imaginary line that connects the North and South poles
Rotation is Earth spinning on its axis…one rotation is one day
Revolution is the movement of one object around another…one year is the time it takes for one revolution around the sun

6. The Seasons Are caused because of how the Earth orbits around the sun.
The axis that the Earth rotates on stays the same (23.5 degrees).
Here is a diagram that will explain the seasons

7. The Seasons

8. Lunar and Solar Eclipses
Solar eclipse occurs when the moon’s shadow falls on the Earth
Lunar eclipse occurs when the Earth’s shadow falls on the moon.
A lunar eclipse can be either a total eclipse or a partial eclipse

9. Lunar and Solar Eclipses

10. Objects in space Universe is all matter and energy
Star is a sphere of gas that has gone through fusion (fuse together)…example would be the North Star or the Sun
Planet is a large, spherical piece of matter that revolves around a star
Galaxy is a collection of gases, dust, and billions of stars…example is the Milky Way
Satellite is an object that orbits around another object…example the Moon

11. Telescopes Galileo (1600’s) was the first to use a telescope
Telescope is a device that makes objects far away appear closer
Refracting telescopes use lenses
Reflecting telescopes use mirrors

12. Common Telescopes

13. Space Shuttles Shuttle is a manned spacecraft that can be reused
Parts of a shuttle:
Solid Rocket Boosters (SRB’s)
Fuel Tank (store liquid hydrogen and oxygen)
Orbiter (the shuttle)

14. Space Shuttle Parts

15. Flight Path of a Shuttle