The Earth

Earth’s Basics

• Earth is classified as a planet.

• It is a sphere • Its diameter is about

12,742 km across. • It is the fifth largest

planet in our solar system.

• Earth is the 3rd planet from the sun.

• Earth’s gravity keeps the moon in orbit.

Planet Mnemonic

My Very Energetic Mother Just Served Us Nachos

Earth’s Axis

• Earth’s axis points to the North Star.

• An axis is an imaginary line that runs from the North Pole to the South Pole.

• The seasons are due to the tilt of Earth’s axis.

North Star

Earth’s Exterior

• About 70% of planet Earth is covered by water.

• The other 30% makes up the seven land continents made of rock.

• Earth’s crust (also called the lithosphere) is made up of two different plates that slide around on the mantle: oceanic plate & continental plate.

• Oceans, mountains, rivers, plains, marshes, glaciers, islands, beaches, valleys, peninsulas, canyons, volcanoes can be found on the crust.

• Earth’s crust is constantly changing due to the effects of weathering, erosion, deposition, the rock cycle, the water cycle, and the weather cycle.

Peninsula

Ocean

Beach

Valley

River

Mountain

Plains

Marshes

Canyon

Glaciers

Island

Volcano

Earth’s Atmosphere

• Earth is the only planet in the solar system that has an atmosphere that can sustain life.

• It protects us from the Sun’s heat and radiation and keeps our planet at a more moderate temperature.

• Our atmosphere contains these gases: – Nitrogen: 78%

– Oxygen: 21%

– Carbon Dioxide: .038%

• Earth’s atmosphere rises up about 10 miles away from the surface of the Earth.

Earth’s Interior

• Inner Core – Solid metal (iron and

nickel)

• Outer Core – Liquid metal (iron and

nickel)

• Mantle – Mostly melted rock – Convection currents

• Crust – Surface that we live

on – Solid rock

flows

Day and Night

• The rotation of the Earth causes day and night.

• It takes 24 hours for Earth to make one turn on its axis.

Daytime Nighttime

Sunrise and Sunset • The apparent motion of the Sun is an illusion.

• Actually the Earth is turning to create this effect.

• The Sun rises in the East and sets in the West! (EW)

SUNRISE SUNSET

Earth’s Seasons Northern

Hemisphere Spring

Northern Hemisphere

Fall

Northern Hemisphere

Summer

Northern Hemisphere

Winter