# Coordinate Systems:

Delphic Oracle comes with the option of calculating charts according to geocentric or topocentric coordinates. The difference between the two is very slight, but is most noticable with the Moon. Geocentric coordinates are the planets coordinates as they would appear from the earth's core. Not very likely since none of us would be able to survive there. Topocentric coordinates calculate planet positions as they appear to the observer in a given location on the surface of the earth. Ideally, the height above sea level is also considered in the topocentric coordinate system, but I set this to "0" as it makes very little difference.

To set your coordinate system, press the <F3> key. The Coordinate group box will be found near the bottom right of this window.