Formation

Maria vs. HighlandsMaria is Latin for “seas”.These areas appear darkand have smooth relativelycrater free surfaces. Theyrepresent the low lyingareas that have been filledin with lava (basalt).

Highlands are literally higherthan the surrounding maria.They lighter in color (andesite)and completely covered by craters.

Maria vs. HighlandsMare Imbrium - Sea of RainMare Serentatis – Sea of Serenity

Mare Crisium- Sea of CrisisMare Tranquilatatis – Sea of

TranquilityMare Fecundatatis – Sea of Fertility

Mare Nectaris – Sea of Nectars

Oceanus Procellarum – Ocean ofStorms

Sinus IridiuimBay of Rainbows

Far Side vs Near Side

The far side lacks Maria

Maria

Highlands

Highlands

Rays• Rays are streaks of dust

and debris from the impact of large meteoroids

• They radiate from the impact crater that created them

• They cover great distances because the Moon lack an atmosphere to restrain them

• They disappear over time so they represent recent impacts

Rays• Rays are streaks of

dust and debris from the impact of large meteoroids

• They disappear over time so they represent recent impacts

Scarps

Scarps are faults.These areas show movementOf the crust.

Rilles• Rilles are collapsed

lava tubes• These are

underground rivers of magma that burn melt through the underground rocks.

• They exist on all terrestrial planets

Rilles

• Lava Tube• on Earth

The Moon has it all

Rebound mountains• These are much like

the drop of water that jumps up after an object has pushed through the surface

• Notice the rays and how the walls of the crater have collapsed due to steepness

Tycho Crater

Tycho Crater

Tycho Crater

Lava flows

Lunar Cycle• A few terms…..

– Waxing = the amount visible is increasing– Waning = the amount visible is decreasing– Crescent = less than 50% visible. ½ of the cycle– Gibbous = more than 50% visible. ½ of the cycle– New Moon = Beginning of cycle (0% visible)– 1st Quarter Moon = ¼ of the way though the cycle

(50% visible)– Full Moon = ½ way through cycle (100% visible)– 3rd Quarter Moon = ¾ of the way through cycle

(50% visible)

Lunar Cycle

Eclipses• The orbit of the Moon

is tilted to the ecliptic.• This creates two

points where the orbits cross called nodes

• Each node represents an eclipse season where there can be a solar or lunar eclipse

Lunar Eclipses• Lunar eclipse always happen at the time of the Full

Moon• The shadow of the Earth consists of two parts

– Umbra = completely in the shadow.

– Penumbra = partially in the shadow

• Lunar eclipses last hours

Lunar Eclipses

Lunar Eclipses

Lunar Eclipses• Lunar eclipses

provide evidence to the ancients that the Earth was round

• The shadow that the Earth casts on the moon is round

• The reddish brown color is due to light refracted through the Earth’s atmosphere

Lunar Eclipses

Lunar Eclipses

Solar Eclipse

• Solar Eclipses always occur at New Moon

• The Moon shadow does not completely cover the Earth so only a small percent of people on Earth get to see the solar eclipses

• The shadow is only about 80 miles wide

Solar Eclipse

Solar Eclipse

Solar Eclipse

• Totality only lasts less than 6 minutes

• During totality we can see the atmosphere of the Sun called the Corona

Solar Eclipse

Solar Eclipse

• Annular eclipses occur when the moon is near apogee at the time of the eclipse

• The last eclipse in Chicago was in 1994 and it was an annular eclipse