Moon Phase Diagram
Define the following terms:
- Rotation: circular motion as an object spins around an
imaginary axis
- Revolution: circular motion as one object orbits another
- Perpendicular: lines that intersect at right angles (90
degrees)
- Cross-hatching: shading using closely-spaced perpendicular
lines
The Moon phase diagram shows two views: the Earth-Moon system Viewed
from Space (showing the Moon in eight different positions in its orbit
around the Earth); and the Moon as Viewed from Earth.
Beginning with the View from Space, use a pencil to complete the Moon
phase diagram. Unless otherwise instructed, use the broad edge of a pencil
to shade the diagram.
Viewed from Space
- Use a dot to locate the North Pole of the Earth and the Moon in each
of its eight positions.
- Use arrows to show the direction of the Earth's rotation
(counterclockwise).
- Use arrows to show the direction of the Moon's revolution around the
Earth. What's the obvious clue to determine the direction of the Moon's
revolution around the Earth?
- Use the broad edge of your pencil to shade night and day on the Earth
and the Moon in each of its eight positions.
- For an observer on Earth, label the following times: 12 Noon; 6 p.m.;
12 Midnight; 6 a.m. (Before you answer the activity question regarding
moonrise and moonset, you should fill in the "in-between" times: 3 p.m.;
9 p.m.; 3 a.m.; 9 a.m.)
- Indicate the lighted side of the Moon that faces the Earth:
- Draw a line that connects the North Pole of the Earth to the North
Pole of the Moon in each of its eight positions.
- Draw a line that is perpendicular to the line you just drew and
that also passes through the North Pole of the Moon (like drawing "Ts").
- For each of the eight positions of the Moon, cross-hatch the lighted
portion of the Moon that faces away from the Earth.
Viewed from Earth
- For each of the eight Moon phases, visualize how the Moon would appear
to an observer on Earth. It is helpful to turn the Moon phase diagram so
that the phase with which you are working is physically at the top of the
page while you imagine that you are standing on the Earth looking toward
the Moon in that position (this helps to determine whether the left or
right side of the Moon is lighted). Use the broad edge of your pencil to
shade the appearance of the Moon.
- Label the names of the eight Moon phases as "Viewed From Earth."
- Label the waxing and waning phases.