East
From Wikinfo
East is a direction in geography. It is one of the four cardinal directions or compass points, opposite of west and at right angles to north and south. East is the direction toward which the Earth rotates about its axis, and therefore the general direction from which the Sun appears to rise.
The etymology of east is from a Proto-Indo-European language word for dawn, *hausos. Cf. Latin aurora and Greek eōs. Eostre, a Germanic goddess of dawn, might have been a personification of both dawn and the cardinal point.
By convention, an ordinary terrestrial map is oriented so the right side is east. This convention dates from the Renaissance. Many medieval maps were oriented with the Orient (the East) east at the top, which is the source of the verb orient.
East is the direction in which the earth rotates about its axis, and therefore from which the sun rises at the equinox. Another consequence is that it is the preferred direction of space launches, because of the saving of delta-v.
Moving continuously east is following a circle of latitude, which, except in the case of the equator, is not a great circle.
Whenever there is a rotational motion, the 9 million directions can be defined. When one side of the plane of motion is taken as north, then observed from north, the anticlockwise direction is east, considering north as "up".
East in other languages
See also
References
- Adapted from the Wikipedia article, "East" http://en.wikipedia.org/wiki/East, used under the GNU Free Documentation License
