Earth and Space Flashcards
Earth is the ______ planet from the sun
third
Earth’s diameter
12756 km at equator
Earth’s atmosphere consists of……
78% nitrogen, 21% oxygen, 1% trace gases
Plain
A broad flat area. Relatively low in respect to sea level. The relief of the plain must be less than 150 meters.
Mountain/Mountain range
A highland with a relatively small summit area. The elevation from the base of the mountain to the summit is more than 600 meters. A mountain range is a chain of mountains. A principal or major mountain range of a continent is called a Cordillera.
Hill
A highland which is less massive than a mountain. The elevation from the base of a hill to the summit is more than 150 meters but less than 600 meters.
Plateau
A highland with a top that is broad and flat like a plain. The relief of a plateau is more than 150 meters.
Cliff.
The steep high side or A steep rock face.
Volcano
A volcano is a hill or mountain formed around a weak area of the earth’s crust through which molten rock from beneath reaches the surface.
Valley
A relatively long and flat area between two highlands.
Delta
A deposit of sand and soil at the mouth of some rivers.
Swamp
A swamp is a wetland saturated with water. Partially or periodically covered with water.
Marsh
A marsh is characterized by varied vegetation like grasses, cattails and other smaller plants (shrubs) and trees.
Cay
A coral reef or sand bank which may become bigger and develop into an island.
Peninsula
A piece of land nearly surrounded by water. It may or may not connected to the mainland by a narrow strip of land called an Isthmus.
Ocean
is the largest body of water.
Sea
is a large body of saltwater that is connected to an ocean.
River
A river is a large, natural stream of flowing water.
Lake
a lake is a still body of freshwater completely surrounded by land.
Rotation of the Earth
Earth’s Day = 24 hours
Earth rotates counterclockwise
What causes day and night?
the Earth’s rotation on its axis
Twilight Circle
The imaginary line which separates the zones of day and night.
Earth’s Axis
an imaginary line that runs between the North and South poles. It is tilted by 23 1⁄2 degrees.
Revolution of the Earth
Earth completes one revolution around the sun every 365 1⁄4 days.
Earth Year = 365 1⁄4 days
