Moon

1
Moon
Retrograde motion of Mars, June to November, 2003
Who is this guy? Use SkyGazer or StarCal to find
out!
2
The Moon

• Facts about the Moon
• We see the moon changes its appearances and
  position in the sky with approximately 30-day
  cycle.
• Unlike the stars, Moon can also be seen during
  the day.
• We also see that the Moon is always involved in
  eclipses, and
• Its position seems to be well correlated with the
  tide of the ocean.
• Understanding the motion of the Moon with respect
  to the Sun and the Earth will explain these
  phenomena.

• The moon revolves around the earth with a period
  of about 29 ½ days one month!

3
Motions of the Sun-Moon-Earth System

1. Earth orbits the Sun every 365 ¼ days
2. Moon orbits Earth every 29 ½ days

4

• The changing phase of the Moon
• The un-changing face of the Moon
• Eclipses
• Lunar Eclipse
• Solar Eclipse

5
The Face and Phases of the Moon

• The phase (how much and which side of the Moon is
  illuminated) of the Moon changes with about one
  month period
• The face (the features on the surface of the
  Moon) does not change at all

6
The Phase of the Moon
The phase of the Moon depends on the relative
position between the Sun, the Earth, and the Moon
7
Phases of the Moon
Click on the image to start animation
8
Moon Rise/Set by Phase
Click on the image to start animation
9
Why do we Always See the Same Side of the Moon?
The rotation period of the Moon with respect to
the universe is exactly the same as the rotation
period of the Moon around the Earth. Is this a
coincidence?
No! ? Tidal Lock, Chapter 5.
10
Seasons, moon, eclipses, tides

• http//qldscienceteachers.tripod.com/junior/astro/
  tides_etc.html