STAAR REVIEW—THE LUNAR CYCLE—CATEGORY 3






The lunar cycle consists of 8 phases, each lasting 3-4 days, for a total of about 29.5 days (approx. 1 month).
We only ever see one side of the moon on Earth because the moon’s rotation and revolution are equal (29.5
days/1 month).
At any given time, only half of the moon is darkened (the side facing away from the sun), while the other half
is lit (the side facing towards the sun).
The lunar phases that we see on Earth are created based on our perspective of the amount of reflected
sunlight on the moon’s surface.
The moon revolves counter-clockwise around the earth.
You are responsible for knowing the 8 phases, in order:
1. New Moon (The start of the cycle; Always in between the sun and the earth; Appears completely
darkened based on our view from Earth)
2. Waxing Crescent (Phase 2; Almost completely darkened based on our view from Earth with a sliver of
light on the right)
3. 1st Quarter (Phase 3; Half shaded based on our view from Earth, with the lighted side being on the
right)
4. Waxing Gibbous (Phase 4; Almost completely lit based on our view from Earth with a sliver of
darkness on the left)
**NOTICE THAT IN THE BEGINNING (WAXING) PHASES, THE LIGHTED PART OF THE MOON THAT WE SEE
ON EARTH IS ON THE RIGHT. WITH THE ENDING (WANING) PHASES, THE LIGHTED PART OF THE MOON IS
ON THE LEFT. ALSO—THE GIBBOUS PHASES HAVE MUCH MORE LIGHT THAN THE CRESCENT PHASES**
5. Full Moon (Phase 5; Completely lit based on our view from Earth)
6. Waning Gibbous (Phase 6; Almost completely lit based on our view from Earth with a sliver of
darkness on the right)
7. 3rd/Last Quarter (Phase 7; Half shade based on our view from Earth, with the lighted side being on
the left)
8. Waning Crescent (Phase 8; Almost completely darkened based on our view from Earth with a sliver of
light on the left)

You also need to be familiar with the difference between Spring and Neap tides, identifying the arrangement
of the earth, moon, and sun during these tides, and recognize at which lunar phases these types of tides
might occur:
Check out these links too!
Lunar Cycle Challenge:
http://sciencenetlinks.com/interactives/moon/moon_challenge/moon_challenge.html
Lunar Cycle Video:
https://www.youtube.com/watch?v=nXseTWTZlks
Lunar Cycle Crossword: