the moon chapter 22.2 the moon chapter 22.2. first, let’s review kepler’s 1 st law first,...

The Moon The Moon Chapter 22.2Chapter 22.2

First, let’s review Kepler’s 1First, let’s review Kepler’s 1stst LawLaw

Creation of the Moon Creation of the Moon “Luna”“Luna”

The Moon is a The Moon is a chunk of Earth chunk of Earth that broke off that broke off during a during a collision collision 4.64.6 billion years billion years ago.ago.

Moon FactsMoon Facts

The moon is The moon is ¼¼ the size of the the size of the Earth.Earth.

There is no There is no oxygen and oxygen and 1/61/6 the amount of the amount of gravitygravity..

Critical ThinkingCritical Thinking

– Calculate how Calculate how much you much you would weigh on would weigh on our Moon…how our Moon…how do you do this?do you do this?

– Does this affect Does this affect your Mass???your Mass???

Why do we only see one side of Why do we only see one side of the Moon?the Moon?

The moon has a:The moon has a:– 27.327.3 Day rotation Day rotation– 27.327.3 Day Day

revolution revolution Because of this we can only see the side of the Moon facing us…only satellites and telescopes have gone to the “Dark side of the Moon”

The Sun’s rays create the The Sun’s rays create the phasesphases!!

Half the moon is always Half the moon is always darkdark The moon The moon revolvesrevolves around the Earth. around the Earth.

The Moon’s The Moon’s RevolutionRevolution around the around the Earth. Earth.

ApogeeApogee = Furthest = Furthest PerigeePerigee = = ClosestClosest

Phases of the Moon Video Phases of the Moon Video ClipClip

Phases of the MoonPhases of the Moon

The moon goesThe moon goes

through itsthrough its

phases every phases every

29.5 days29.5 days

NewNew Moon Moon When the moon is in When the moon is in

between the sun and between the sun and the Earth, we cannot the Earth, we cannot see the moon. see the moon.

FullFull Moon Moon When the Earth is When the Earth is in in

between between the moon and the moon and the sunthe sun

The surface of the moon The surface of the moon that we can see is that we can see is litlit up. up.

QuarterQuarter Moon Moon When the Moon, Earth When the Moon, Earth

and Sun make a and Sun make a right right angle. angle.

We can only see We can only see halfhalf of the lit area of the of the lit area of the moon.moon.

GibbousGibbous Moon Moon When the moon is in When the moon is in

between the between the fullfull and and quarterquarter moon phases. moon phases.

Most of the moon is lit Most of the moon is lit up. up.

New to Full = New to Full = waxing moonwaxing moon. .

Full to New = Full to New = waning waning moonmoon. .

Let’s Take a break from Notes Let’s Take a break from Notes and Pretend we are lost on and Pretend we are lost on

the Moon!!!!the Moon!!!!

EclipsesEclipsesChapter 22.1Chapter 22.1

An Eclipse is caused by the shadow of the Earth or the Moon..

Earth

Moon

Let’s Ask an Astronomer Let’s Ask an Astronomer about Solar Eclipses!about Solar Eclipses!

Shadow StructureShadow Structure

Penumbra

Penumbra

Umbra

Solar Solar EclipsesEclipses The Moon’s The Moon’s

Shadow Shadow blocksblocks out the Sun.out the Sun.

The Moon is in The Moon is in between the between the Sun Sun and the Earthand the Earth. .

New Moon New Moon PhasePhase (Happens during the (Happens during the

day)day)

A Total Solar Eclipse from beginning to end

Why not a solar eclipse every Why not a solar eclipse every month then?month then?

Sun

Ecliptic

Moon

Moon’s Orbit

Earth5o

Moon's orbit is tilted about 5o to the Earth's orbit, so the shadows usually miss!

Next total solar eclipse in our area…August 21, 2017

AnnularAnnular Solar Eclipse Solar EclipseThe The moon’s shadow moon’s shadow doesn’t quite doesn’t quite reachreach the Earth the Earth

leaving a ring around the moon during an eclipse. leaving a ring around the moon during an eclipse.

Partial Partial Solar EclipseSolar Eclipse

You might only see part of the Sun’s face blocked because of where you are viewing the eclipse.

LunarLunar Eclipse Eclipse (Happens at Night)(Happens at Night)

Moon

SunEarth

Moon’s PathOccurs when the Earth lies

between the Sun and Moon, so that Earth's shadow darkens the Moon. Full Moon Phase

The moon becomes a blood red color during a total lunar eclipse because of how the light reflects in the atmosphere. No wonder that ancient cultures feared the appearance of the moon during a lunar eclipse.

Earth’s Atmosphere

Sunlight

MoonEarth

The Blood MoonThe Blood Moon

The moon often does not totally disappear during a total lunar eclipse. Instead it can be seen as a very dark red color because of the refraction of sunlight through the Earth's atmosphere.