1. Moon
Phases

3. Half of the Moon is always lit up by the
sun. As the Moon orbits the Earth, we
see different parts of the lighted area.
http://www.nasm.si.edu/apollo30th/moontheater/phasepage2.html

4. The revolution of the Moon around the
Earth makes the Moon look as if it is
changing shape in the sky.
http://btc.montana.edu/ceres/html/birthdayphases.htm

5. Phases of
the Moon
It is caused by
the different
angles from
which we see
the lighted part
of the Moon's
surface.
http://btc.montana.edu/ceres/html/birthdayphases.htm

7. 1. New Moon
• The Moon's not
illuminated side is
facing the Earth.
• The Moon is not
visible (except
during a solar
eclipse).

8. 2. Waxing Crescent
• The Moon appears to
be partly but less
than one-half
illuminated by direct
sunlight.
• The fraction of the
Moon's disk that is
illuminated is
increasing.

9. 3. First Quarter
• One-half of the
Moon appears to
be illuminated by
direct sunlight.
• The fraction of the
Moon's disk that is
illuminated is
increasing.

10. 4. Waxing Gibbous
• The Moon appears to
be more than onehalf but not fully
illuminated by direct
sunlight.
• The fraction of the
Moon's disk that is
illuminated is
increasing.

11. 5. Full Moon
• The Moon's
illuminated side is
facing the Earth.
• The Moon appears
to be completely
illuminated by
direct sunlight

12. 6. Waning Gibbous
• The Moon appears to
be more than one-half
but not fully illuminated
by direct sunlight.
• The fraction of the
Moon's disk that is
illuminated is
decreasing.

13. 7. Last Quarter
• One-half of the
Moon appears to
be illuminated by
direct sunlight.
• The fraction of the
Moon's disk that is
illuminated is
decreasing.

14. 8. Waning Crescent
• The Moon appears to
be partly but less
than one-half
illuminated by direct
sunlight.
• The fraction of the
Moon's disk that is
illuminated is
decreasing.

16. Waxing
(Right is
illuminated)
Waning
(Left is
illuminated)