THE MOON AND THE SUN
OUR MOON ON FEBRUARY 2, 2011
How has the Moon changed the last
week?
 Is there a volunteer to draw what they
saw on the board?
 What shape would you predict
tonight?
 Does anyone know the name of this
Moon phase?
 Why does this change occur?
 Did anyone observe the Moon at the
same time each evening?
 Was the Moon always in the same
location in the sky?

PHASES OF THE MOON



Cycle requires 29.5
days
The synodic month
Each phase depends
on its position
relative to the Sun
as it orbits Earth
THE MOON RISES 53 MINUTES LATER EACH DAY
Crescent waxing
Moon sets in the
west at sunset
Crescent
waning Moon
rises at sunrise
Full Moon rises in the
east at sunset
Notice the direction of the crescent moon, waxing versus waning.
When the bright part is getting bigger, the Moon is
waxing.
 When it is getting smaller, the Moon is waning.
 When the Moon is more than half-lit, it is called a
gibbous Moon.
 When the moon is less than half-lit, it is called a
crescent Moon.

WHAT IS THE NAME OF THE
MOON’S PHASE LAST NIGHT?
Waning crescent
MOON’S
FORMATION
A
5.17
large size planet ,
thought to be the size
of Mars, collided with
Earth- 4.4 billion
years ago
 Heavier more dense
material was held by
the Earth’s
gravitational pull The
debris formed the
moon
DAY SIDE OF THE MOON: HIGH TEMPERATURES
NIGHT SIDE: VERY LOW TEMPERATURES
The period (the time it takes
to make one complete
turn)around the axis and its
revolution around Earth are
the same.
The same
lunar
hemisphere
always faces
Earth
Surface scarred with meteor impact craters implies lack of crustal movement.
THE SIDEREAL MONTH: WHEN THE EARTH,
MOON, AND DISTANT STARS ARE ALIGNED
THE MOON’S INFLUENCE ON EARTH
SEASONS
The impact, set the Earth on its axis
23.5 degrees
 Seasons help regulate the Earth’s temperature

MOON’S GRAVITATIONAL FORCE INFLUENCES THE
EARTH’S TIDES
Variations of
tides is
determined by
the Moon’s
location in
respect to the
Earth and
Sun.
New moon
Full moon
Earth
5.2
°
The Sun and Earth lie in one plane
 The Moon’s orbit around Earth lies in another
 The shadows of either Moon or Earth are normally
avoided
 Two times a year this pattern is changed.

Sun
LUNAR ECLIPSE, AUGUST 28, 2007

The moon passes through
the Earth’s shadow
FEBRUARY 9, 2009


Penumbra lunar eclipse
Sketch a diagram of a
lunar eclipse. Label the
Sun, Moon, Earth, umbra
and penumbra.
Sketch a circle where a
penumbra lunar eclipse
would be located.
DECEMBER 21, 2010,
LUNAR ECLIPSE
JUNE 15, 2011, LUNAR ECLIPSE
Draw a diagram showing a lunar
eclipse and label with the following
terms: Sun; Earth; Moon; umbra and
penumbra
OUR STAR
Early people worshiped
the Sun
 Mid-1800s: size and
distance was understood
 Late 1800s:
gravitational
contraction


A shrinking gas cloud
heats up because some of
the gravitational energy
is converted to thermal
energy
COLLAPSE OF LARGER STAR:
SUPERNOVA
•Protostar heats up- fusion: H
•Star is created
He
Supernova explosion
creates more complex
elements
Formation of heavier elements
WHY DOES THE SUN SHINE?






Einstein’s theory of
relativity in 1905
E = mc2
E= energy
M= mass
C= speed of
light(186,000m/s)
An enormous amount of
energy produced from a
tiny mass
WHY DOES THE SUN SHINE?

Fusion:
Fusion: the combination
of elements- increasing
the atomic number
LIFE CYCLE OF OUR SUN
WHERE IS OUR SUN IN THIS
PROCESS?
•5 billion years old
•5 billion more years to go
HYDROGEN FUEL IS EXHAUSTED IN
CORE: FUSION CONTINUES IN OUTER
SHELL
Core contracts. The contraction causes an increase in temperature.
RED GIANT FORMS: INCREASE OF
ENERGY
Outer gaseous shell expands
 In
5 billion years our
sun will form a red
giant star
 The size will
increase to include
the location of the
Earth’s orbit
 When all fuel is
consumed,
gravitational force
will cause collapse
into a planetary
nebula
PLANETARY NEBULA

Collapsed expanding spherical cloud of gas
Helix Nebula:
planetary
nebula
450 light years away
WHITE DWARF IS FORMED
No more nuclear
reactions
 Gravitational force will
no longer pull gas into
contraction
 Glows because of its
residual heat

HOW DOES THE SUN MAINTAIN ITS SIZE?




High temperatures and
densities are in the Sun’s
core
Gravitational force pulls
inward
Pressure pushes outward
Gravitational
equilibrium
THE SUN’S STRUCTURE
The sun is a ball of
plasma- free flowing
atomic particles can
create and respond to
magnetic fields
 Different densities and
temperatures of the
plasma give the Sun a
layered structure

SUN’S SIZE
300,000 times the mass of Earth
 Diameter is 865,000 miles (Earth’s diameter, 8,000
miles)

SOLAR ACTIVITY
Sun’s surface churns with rising and falling gas
 Sunspots: spots that are less bright because they are
cooler
 Regions with strong magnetic fields
 Charged particles from the plasma follow the magnetic
field lines

SOLAR ACTIVITY
Solar flares: changes in magnetic field lines near
sunspots
 Magnetic field lines become twisted and are unable to
maintain the shape
 Generating X-rays and charged particles nearly the
speed of light

SOLAR WIND
A stream of charged particles continually blown outward
in all directions from the Sun
 Earth’s strong magnetic field protects the planet from the
magnetic field
 Forms the tails of comets as they move toward the Sun

Magnetosphere:
formed from the
magnetic field, shown in
blue
SOLAR WIND





Aurora: borealis
(northern); australis
(southern)
Solar wind particles get
inside the magnetosphere
Trapped particles gain
energy and are able to
follow the magnetic field
into the Earth’s
atmosphere
Particles collide with
atmospheric atoms and
molecules
Collisions cause moving
lights
SOLAR ECLIPSE: AUGUST 1, 2008
MOON’S SHADOW IS NEVER WIDER THAN 170
MILES.
SOLAR ECLIPSE, JULY 2009
Draw a diagram showing a solar eclipse and label with the following
terms: Sun; Earth; Moon; umbra and penumbra
NEXT SOLAR ECLIPSE