Moon Phases

1
Moon Phases
2
(No Transcript)
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/phas
epage2.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.h
tm
5

• This is caused by the different angles from which
  we see the lighted part of the Moon's surface. 
  These are called "phases" of the Moon. 

http//btc.montana.edu/ceres/html/birthdayphases.h
tm
6
http//www.niehs.nih.gov/kids/lunar/why_phases.gif

7

• The Moon passes through eight major phases
  during a cycle that repeats itself every 29.5
  days.  The phases always follow one another in
  the same order

8
New moon Waxing crescent First quarter Waxing
gibbous Full moon Waning gibbous Third
quarter Waning crescent
9
New Moon

• The Sun, Earth, and Moon are almost in a straight
  line, with the Moon in between the Sun and the
  Earth. 
• New Near (the sun)
• This means that the lighted side of the Moon
  faces away from the Earth. 
• So the Moon that we see looks very dark

10
New Moon
11
Waxing Crescent Moon

• This Moon can be seen about day 4 after the New
  Moon.  The crescent will grow larger and larger
  every day
• "Waxing" means increasing, or growing larger
  think wax build up!!
• Right Build Bright

http//btc.montana.edu/ceres/html/birthdayphases.h
tml
12
Waxing Crescent Moon
http//btc.montana.edu/ceres/html/birthdayphases.h
tml
13
First Quarter Moon

• On about day 7, the moon has revolved to a 90
  angle from the Earth and Sun.
• The right half of the Moon appears lighted and
  the left side of the Moon appears dark. 
• Also called a Half Moon

14
First Quarter Moon
15
Waxing Gibbous Moon

• At about day 10 we can roughly see about three
  quarters of the moon

http//btc.montana.edu/ceres/html/birthdayphases.h
tml
16
Waxing Gibbous Moon
http//btc.montana.edu/ceres/html/birthdayphases.h
tml
17
Full Moon

• At roughly 2 weeks
• The Sun, Earth, and Moon are nearly in a straight
  line, with the Earth in the middle. 
• Full Far (from Sun)
• The Moon that we see is very bright from the
  sunlight reflecting off it.

18
Full Moon
19
Waning Gibbous Moon

• "Waning" means decreasing, or growing smaller.
• At about day 18
• The amount of the Moon that we can see will grow
  smaller and smaller every day.

http//btc.montana.edu/ceres/html/birthdayphases.h
tml
20
Waning Gibbous Moon
http//btc.montana.edu/ceres/html/birthdayphases.h
tml
21
Third (Last) Quarter Moon

• About day 22
• The left half of the Moon appears lighted, and
  the right side of the Moon appears dark. 

22
Third Quarter Moon
23
Waning Crescent Moon

• At about day 26
• The crescent will grow smaller and smaller every
  day, until the Moon looks like the New Moon.

http//btc.montana.edu/ceres/html/birthdayphases.h
tml
24
Waning Crescent Moon
http//btc.montana.edu/ceres/html/birthdayphases.h
tml
25
http//www.opencourse.info/astronomy/introduction/
04.motion_moon/moon_phases.gif
26
Waxing Waning
http//www.nasm.si.edu/apollo30th/moontheater/phas
epage4.html
27
http//www.nasm.si.edu/apollo30th/moontheater/phas
epage4.html
28
http//www.calvin.edu/lmolnar/moon/images/phases.
gif