Chapter+12

Welcome to chapter 12! There is a discussion board at the bottom of the page. Please leave any questions you may have about the chapter, homework, or questions you are struggling with. If you're having trouble accessing the discussion board, please send me an email!

**CHAPTER VOCABULARY** You can participate online by providing explanations for vocabulary in your own words. You can give examples if it helps your explanation of words. You can do one or five or ten and you can add on to posts that have already been made if you would like to improve an explanation. Don't forget to leave your name beside text that you write.

**astronomy** - an area of science that studies and explains things that happen outside of Earth's atmosphere (Erin Lee)

**astronomer** - an expert in astronomy who often goes to outer space to explore and study space (Erin Lee)

**rotation** - the act of rotating, or spinning, around the axis or centre (Erin Lee)

**revolution** - the circular or elliptical movement of an object around different axis or centre i.e. Earth's Revolution (Erin Lee) source: http://www.physicalgeography.net/fundamentals/6h.html

**photoperiod** - the hours of daylight after sunrise and before sunset (Erin Lee)


 * planets - **astronomical objects that wander (a.k.a orbit) around stars; massive that they are rounded by their own gravvity (Jordan Choi)


 * retrograde motion **


 * precession **


 * perihelion - The point at which Earth is closest to the Sun (Justin) **


 * aphelion - ****The point at which Earth is farthest to the Sun (Justin) **


 * <span style="font-family: Georgia,serif;">constellations- 88 different patterns of stars on the sky (Justin) **


 * <span style="font-family: Georgia,serif;">celestial sphere - In middle age people thought that the sky was an solid object. Also, they thought that stars were atteched to an invisible sphere which they called celestial sphere. (Andrew Park) **


 * <span style="font-family: Georgia,serif;">celestial equator **


 * <span style="font-family: Georgia,serif;">plane of the ecliptic **


 * <span style="font-family: Georgia,serif;">equinoxes **


 * <span style="font-family: Georgia,serif;">solstices **


 * <span style="font-family: Georgia,serif;">circumpolar **


 * <span style="font-family: Georgia,serif;">lunar cycle **


 * <span style="font-family: Georgia,serif;">solar eclipse - Eclipse that occurs during a new moon, when the Moon is between Earth and the Sun (Justin) **


 * <span style="font-family: Georgia,serif;">lunar eclipse - Eclipse that occurs during a full moon, when Earth is between Earth and the Sun (Justin) **


 * <span style="font-family: Georgia,serif;">nodes **


 * <span style="font-family: Georgia,serif;">tides: Large body of water in Earth rising and falling by pull of Moon's weight (HeeSoo Choi) **


 * <span style="font-family: Georgia,serif;">nebula **


 * <span style="font-family: Georgia,serif;">protoplanets **


 * <span style="font-family: Georgia,serif;">outer planets **


 * <span style="font-family: Georgia,serif;">gas giants **


 * <span style="font-family: Georgia,serif;">inner planets **


 * <span style="font-family: Georgia,serif;">terrestrial planets **


 * <span style="font-family: Georgia,serif;">minor bodies **


 * <span style="font-family: Georgia,serif;">asteroids- It is often called minor planet which is small part of our solar system that orbits around the sun. (Never called as a planet) (Andrew Park) **


 * <span style="font-family: Georgia,serif;">meteoroids **


 * <span style="font-family: Georgia,serif;">meteors- **<span style="font-family: Georgia,serif;">meteoroid that entered the Earth's atmosphere;an urban legend is that if you pray as soon as you witness a metor (shooting star), that wish will come ture (Jordan Choi) picture below


 * <span style="font-family: Georgia,serif;">meteorites- **<span style="font-family: Georgia,serif;">meteroites are the object that enteres the atmosphere of the object such as Eath and impacts its surface. (Andrew Park)


 * <span style="font-family: Georgia,serif;">comets **


 * <span style="font-family: Georgia,serif;">Big Splash theory **


 * <span style="font-family: Georgia,serif;">astronomical unit (AU) **


 * <span style="font-family: Georgia,serif;">astrolabe **


 * <span style="font-family: Georgia,serif;">geocentric **<span style="font-family: Georgia,serif;">- geo:earth centric:center; refering to a system based on Earth (Earth as the center) (Jordan Choi)


 * <span style="font-family: Georgia,serif;">heliocentric - **<span style="font-family: Georgia,serif;">helio:sun centric:center; saying the sun is the center (Jordan Choi)


 * <span style="font-family: Georgia,serif;">Kepler’s Laws of ****<span style="font-family: Georgia,serif; line-height: 1.5;">Planetary Motion **

**<span style="font-family: Georgia,serif; font-size: 17.77777862548828px;">CHAPTER CONTENT ** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12.1 The Night Sky** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12A: Sunset and Sunrise: Measuring the Photoperiod** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">Use the following dates: Jan 1, Jan 15, Jan 29, Feb 12, Feb 26, Mar 12, Mar 26, Apr 9, Apr 23, May 7, May 21, Jun 4, Jun 18, July 2, July 16, July 30, Aug 13, Aug 27, Sep 10, Sep 24, Oct 8, Oct 22, Nov 5, Nov 19, Dec 3, Dec 17, Dec 31 <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12.2 The Earth-Moon System** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12.3 Our Solar System** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12.4 A Closer Look at the Planets** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">These powerpoint slides have been setup for you. It is up to you to create the notes from the textbook. <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**12.5 The History of Astronomy** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;"> <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">**CHAPTER REVIEW ANSWERS** <span style="display: block; font-family: Georgia,serif; font-size: 16.666667938232422px;">