Moon, Moon Phases & Eclipses

1
Moon, Moon Phases Eclipses
2
The Moon
3
Myths about the Moon
The Moon is made of cheese!                      
           There is a Man in the Moon.    The
Moon and the Sun chase each other across the
sky.  The Moon disappears during certain days of
the month. There are men or other creatures
living on the Moon.  The Moon was put in the sky
by a person or animal.  The Moon is a living
creature or a god.  The Moon controls how we act
and how we feel.               During a full
moon, some people turn into werewolves.  The
Moon is pulled across the sky by a person,
animal, or force.    
4
Myths

• Greek goddess Artemis, roman goddess Diana

5
Myths

• Chinese mythology Change
• Moon festival

6
Calendar

• The current standard calendar is solar calendar
  (Gregorian calendar) counting days
• The moon phases have a period of 29.5 days, a
  good measure of time
• Lunar calendars counting days and months
• E.g. Islamic calendar is a lunar calendar
• 29.5 12 354, 11 days less than 365
• Lunisolar calendar Chinese calendar, Hebrew
  calendar
• Adding leap months, with a circle of 19 years

7
Moon our closest natural neighbor

• The earths only natural satellite
• Orbit around the earth is an eclipse
• Average distance from the earth to the moon is
  384,403 kilometers (238,857 miles) 30 times the
  diameter of the earth
• Diameter of 3,474 km, ¼ of the earth
• Gravity 1/6 of the earth

8
Moons orbit

• The orbit period around the earth 27.3 days
• The spin period is exactly the same!
• We always see the same side of the moon!
  ( precisely speaking 59 of the surface during
  the whole period of the moon revolution. Reason
  libration)
• The period of Lunar Phase 29.5 days
• Because of the earths revolution in the space
• The orbit plane of the moon is tilted by 5
  degree with respect to the earths orbit around
  the sun, unlike other planets

9
Moons orbit

• The orbit plane of the moon is tilted by 5
  degree with respect to the earths orbit around
  the sun, unlike other planets

10
(No Transcript)
11
Near Side
Far Side
12
Moons surface

• Maria (sigular mare, sea in Latin)
• Dark areas and were thought to be seas
• Cover 31 of the near side, but only 2 of the
  far side
• No water but vast pools of solidified lava that
  flowed into basins formed by comets/metors
  colliding
• Nomenclature
• Latin terms describing the weather and abstract
  concepts
• Smaller dark regions
• Lacus (Lake)
• Palus (marsh)
• Sinus" (bay)

13
Moons surface

• Highland
• Lighter color regions, or called Terrae
• Many are impact basins outer rims
• In contrast to earth, no major lunar mountains
  were formed as a result of tectonic events
• Mountains and mountain ranges
• Different brightness of the highlands and maria
  is because they are composed of different rock
  types

14
Craters

• Formed when asteroids/comets hit the lunar
  surface
• Half a million craters with diameters larger than
  1km
• Crater counting to estimate the age of the
  lunar surface
• The largest crater is South Pole-Aitken basin,
  with 2,240 kms in diameter and 13 kms in depth
• Nomenclature
• Large craters, deceased famous scientists,
  artists
• Small craters, common first names

• Daedalus, 93 km in diameter
• Proposed as a site for a large radio telescope

15
Known maria, highlads and craters
16
The formation of the moon

• Born from the earth - broke off from the earth by
  centrifugal forces, and left the pacific ocean
  behind
• Captured by the earths gravity
• Co-formation with the earth
• Giant impact hypothesis
• An impact of a Mars-sized body collide w/ the
  proto-Earth and ejected materials to orbit around
  the earth the Moon

17
Explorations of the moon

• Ancient people observed the moon by naked eyes,
  and wrote poems and essays, and told myths
• Galileo first observed the moon using an
  telescope
• The only celestial body the human being has
  orbited and landed
• First impact Luna 2 of Soviet Union in 1959
• First far side picture Luna 3 in 1959
• First soft landing Luna 9 in 1966
• First mens step on the moon Apollo 11 in 1969

18
Moon Phases

• Why does the moon change phases?
• Lunar phases are the result of our eyes seeing
  the illuminated half of the Moon from different
  viewing geometries
• Due to the Moons orbital positions

19
The Moons Orbit around the earth
20
(No Transcript)
21
Moon Phases
22
Complete this
Say, Sun rises at 6am and sets at 6pm
23
When new moon occurs, what is the phase of the
earth if you stand on the moon?
Full earth!
The earth always has an opposite phase to the
moon.
24
Eclipses

• Have you seen eclipses?
• What are eclipses in nature?
• One celestial object casts its shadow on the
  other one

25
Solar Eclipses

• Sun the shadow of the moon on the earth

Total solar eclipse in 1999
26
A total eclipse B annular eclipse C partial
eclipse
27
Lunar Eclipses

• Moon the shadow of the earth on the moon

28
(No Transcript)
29
Lunar Eclipse
30
Whats the moon phase when a solar eclipse occurs?
New Moon
Whats the moon phase when a lunar eclipse occurs?
Full Moon
31
Why arent there solar eclipses and lunar
eclipses on EVERY new moon and full moon?
32

• Two conditions must be satisfied for an eclipse
  to occur
• The nodes of the moons orbit must be nearly
  aligned with the Sun and the Earth
• The phase of the moon must be new or full

33
Eclipses Cycle

• Every year there are at least two lunar eclipses
• Lunar eclipses and solar eclipses always come in
  pairs
• Lunar eclipses can be seen everywhere on the
  earth, but the solar eclipses may only be seen on
  part of the earth

34
(No Transcript)
35
Solar eclipses