Unit 0

A rocky body smaller than a planet; most revolve around the Sun in belts while others cross the orbits of planets

• Asteroid

• Comet

• Equinox

• Star

A great explosion in which the universe was formed 13.8 billion years ago; the explosion threw matter in all directions and caused space to expand; when the universe cooled, matter condensed to form the different celestial bodies

• Meridians

• Leap Year

• Big Bang

• Revolution

Different colors are used to show areas with the same statistical characteristics, such as population density

• Time Zone

• Choropleths

• Map Projection

• Parallels

Made of ice, dust, and rocks; visible as they approach the sun

• Planet

• Asteroid

• Longitude

• Comet

Two days in the spring and autumn in which the sun’s rays hit the surface of the Earth most directly at the Equator; the daytime is the same length in the nighttime on these two days

• Equinox

• Solstice

• Isolines

• Rotation

Parallels and meridians, to locate an exact point on the map with precision

• Isolines

• Geographic Coordinates

• Scale

• Thematic Map

Shows scale as a line divided into segments, similar to a ruler; each segment indicates the real distance on the ground

• Graphic Scale

• Latitude

• Parallels

• Planet

Lines that are drawn to connect places that share the same value, such as isotherms on a weather map, which join points with the same temperature

• Meridian

• Rotation

• Topographic Map

• Isolines

the angular distance of a location north or south of the equator; the greatest latitudes are 90 degrees north and 90 degrees south, which mark the North and South Poles

• Numerical Scale

• Longitude

• Latitude

• Meridians

Every fourth year in which an extra day is added to the month of February to correct the six extra hours that it takes the Earth to go around the Sun

• Leap Year

• Equinox

• Time Zone

• Star