Geography I

Great Circle

A line running in any direction over the surface of the globe, the resulting plane would pass through the center of the globe cutting the globe into two equal hemispheres. A great circle is 1) the shortest distance between two points on the globe, and 2) the largest diameter circle that can be drawn on the glove

Daylight Saving Time

An adjusted time system where clock time, within a time zone, is sent one hour ahead of standard time.

July 4

Date of Aphelion

Star

Energy emitting, gaseous celestial body

Latitude

Lines that run east-west around the globe and measure angular distance north and south of the equator. All lines are parallel to each other and of decreasing diameter from the equator to the poles, and the poles are points. Only the Equator is a great circle

Parallels of latitude

Lines that run east-west around the glove and measure north and south of the equator. Opposite parallels carry the same numerical value but are in opposite hemispheres

Longitude

Lines that run north-south and converge at the poles, but measure angular distance east-west from the Prime Meridian.

Topic of Cancer

Northernmost point of migration of the vertical sun ray, the 23.5 degree north parallel of latitude

Planet

One of nine light-reflecting bodies orbiting the sun.

Meridians of Longitude

One-half of a great circle longitude line running form pole to pole. Two opposite meridians form a great circle longitude line and the numbers of the who must add up to 180 degrees and be in opposite hemispheres.

Quadrant

One-quarter of the glove divide by the equator and the prime meridian/IDL.

International Date Line

The 180 degree meridian of longitude where the new day starts and the old day ends. it is directly opposite the prime Meridian.

Parallelism

The Earth's axis remains parallel to itself at all points in its orbit

Revolution

The Earth's motion in orbit around the sun which takes 365.25 days axial rotation and is the basis for the calendar year

Longitudinal Extent

The East-West measurement of an area of the Earth, bounded by meridians of longitude

Arctic Circle

The Parallel of latitude located at 66.5 (degrees) north which is the farthest distance the tangent (zero (degrees)) sun ray migrate each side of the south pole during the solstices.

Antarctic Circle

The Parallel of latitude located at 66.5 (degrees) south which is the farthest distance the tangent (zero (degrees)) sun ray migrate each side of the south pole during the solstices.

Low Latitudes

The Region of the globe lying between 30 degree north and 30 degrees south latitude which experience the high sun angle throughout the year. This global region receives the greatest amount of solar energy during the year.

Circle of illumination

The boundary between day and night on the earth, which is either dawn or dusk

Standard Time

The commonly accepted time within a 15 degree band of longitude

Zenith

The highest point in the sky that the sun reaches during the course of a day from sunrise to sunset

Terminator

The line dividing light and dark on a planet or moon

Elliptical Orbit

The non-circular shape of the path of all planets as they revolve around the sun.

Latitudinal extent

The north-south measurement of the area of the Earth bounded by parallels of latitude

Pole

The northern or southernmost point on a planet where the rotational axis intersects the planet surface

Aphelion

The point in the Earth's orbit when the earth is farthest from the sun, 94.5 million miles. Occurs on approximately July 4

Middle latitudes

The regions of the globe lying between 30 degree and 60 degree north and south latitudes. These regions never experience the 90 degree sun angle and exhibit greater seasonal variation due to higher sun angles and long days during the summer and low sun and short days during the winter.

High Latitudes

The regions of the glove located between 60 degrees and 90 degrees north or south latitudes which experience the lowest sun angles during the year and lose more energy than they receive.

Small Circle

The result of a plane cutting through any part of the globe except the center. Any two points on the line formed by the edge of this plane at the global surface would not be shortest distance between the two points on the globe

Solar System

The sun w/ its orbiting planets, asteroids and occasional comets held by their mutual gravitational attraction

Ecliptic

The theoretical plane formed by the Earth's orbit as it moves in its orbit around the Sun. This plane passes through the centers of the Earth and sun.

Rotation

The turning of the Earth on its axis from west to east through 360 degree of angle in approximately 24 hours

Equinox

The two times during the year when the vertical rays of the sun are at the equator, and day and night are each 12-hours long over the entire globe. These are known as the spring (vernal) and fall (autumnal) equinoxes.

Prime Meridian

The zero degree longitude line that runs from pole to pole through greenwich, England.

Equator

The zero-degree latitude line around the glove half way between the north and south

Solar time

Time based on the apparent motion of the sun.

Perpendicular ray

When the sun is directly overhead at noon and the rays intersect the earth surface at 90 degrees. Vertical rays are found only between 23.5 degrees N/S

Tropic of Capricorn

southernmost point of migration of the vertical sun ray, the 23.5 degree south parallel of latitude

Inclination

the 23.5 degree tilt of the Earth's axis from a perpendicular passing through the plane of the plane ecliptic

Solstice

the moment during the year when the vertical rays of the sun reach their highest latitude which is marked by the Tropic of Cancer and the Tropic of Capricorn.

Periheion

the point in the earth's orbit when the earth is closest to the sun 91.5 million miles. Occurs Jan 3