Earth / Moon RelationshipsTides, Eclipses, Phases, & Formation

Rotating & Revolving

• Rotating– The spinning of a

planet, moon, sun or other object on its axis.

• Revolving– The orbital path

of a space object as it moves around another.

Earth's rotation and axis animation

http://highered.mcgraw-hill.com/sites/dl/free/007299181x/59233/8_1.htm

Earth Revolves around the Sun

Phases of the Moon

< New

< Waxing Crescent

< First Quarter

< Waxing Gibbous

< Full

< Waning Gibbous

< Third Quarter

< Waning Crescent

Tides

• Tides– Daily rise and fall

of the Earth’s waters caused by the gravitational pull of the moon and sun.

Tides

• Tides• Spring

– When the sun and the moon are aligned the pull is greater on the earth, thus a greater tide.

Tides

• Tides• Spring• Neap

– When the sun and moon are at right angles to each other their pull is counteracted creating lower tides.

Tides animation

http://highered.mcgraw-hill.com/sites/dl/free

http://highered.mcgraw-hill.com/sites/dl/free/007299181x/59233/5_13.htm/007299181x/59233/5_13.htm

Eclipses

• Solar Eclipse– The Moon passes

between the Earth and the Sun casting a shadow on the Earth.

Eclipses

• Solar Eclipse• Lunar Eclipse

– During a Full Moon the shadow of the Earth can then be seen cast onto the Moon.

Eclipses

• Umbra– The area of

shadow that creates a total eclipse.

• Penumbra– The area of

shadow that creates a partial eclipse.

Eclipses

• Umbra– The area of

shadow that creates a total eclipse.

• Penumbra– The area of

shadow that creates a partial eclipse.

Moon Formation• The Fission Theory:

– The Moon was once part of the Earth and somehow separated from the Earth.

• The Capture Theory:– The Moon was formed somewhere else, and was later captured by

the gravitational field of the Earth. • The Condensation Theory:

– The Moon and the Earth condensed together from the original nebula that formed the Solar System.

• The Colliding Planetesimals Theory:– The interaction of very large chunks of rocks like asteroids

condensed to from the Moon. • The Ejected Ring Theory:

– A planetesimal the size of Mars struck the earth, ejecting large

volumes of matter. A disk eventually condensed to form the Moon.

Formation Video

Credits

• http://www.spaceweather.com/eclipses/images/09jan01/zirn1_big.jpg

• http://www.hermit.org/Eclipse• http://aa.usno.navy.mil/faq/docs/

moon_phases.html• http://www.classzone.com/books/

earth_science/terc/content/visualizations/es2501/es2501page01.cfm?chapter_no=25

• http://csep10.phys.utk.edu/astr161/lect/moon/moon_formation.html

• http://science.nasa.gov/ssl/pad/solar/sunturn.htm