Moon Phases Understand how Moon phases work on

Moon Phases • Understand how Moon phases work on the Earth • More world building! • Examples: – Indigenous religions, local calendars – Werewolves, spaceflight, tides and ocean travel • Bad example: “The Moon told me so. ”

Which situation would produce this phase? D A C B

Demos • Three views of Moon Phases: http: //astro. unl. edu/classaction/animatio ns/lunarcycles/moonphases. html • Moon Phases and where in sky: http: //astro. unl. edu/classaction/animatio ns/lunarcycles/lunarapplet. html

Cause = Sun-Moon-Earth angles

http: //www. astronomy. ohiostate. edu/~pogge/Ast 161/Unit 2/Images/moonphase. gif

Which situation would produce this phase?

Western cultures recognize 8 Moon phases, some spread over multiple nights 1 2 3 4 5 6 7 8 1

Phase cycle takes 29. 53 days

Waxing Crescent First Quarter Waxing Gibbous Waning Gibbous Full Waning Crescent Last Quarter (not pictured) New

Traditional Hawaiian culture uses 30 Moon phases http: //www. imiloaha waii. org/57/

Bad Example: “The Moon told me so. ” • In Rise of the Guardians (2012), the Moon is an important plot element, and over four days it is Full, Waning Gibbous, and Full. Day 1 Day 2 Day 3 Day 4

Worksheet!

What if there are multiple moons? • Each moon would have a different orbital period • Each would be at a different angle to the Sun on a given day – Each would be in a different phase on the same day – The order of phases would be the same (unless retrograde), but might last for longer or shorter times

More Misconceptions • http: //www. youtube. com/watch? v=Lqa. D f 2 fu. UH 8

• Tonight is Waning Gibbous, will we see it? • Resource: USNO (US Naval Observatory for Sun/Moon rise/set times