State Vectors are Cartesian
describing the position and velocity, or state of a satellite. As with
6 basic coordinates are required to fully specify the position at a given
The first 3 values are the position in a right-angled
(X, Y, Z, for inertial coordinates (ECI coordinates), or E, F, G
for earth-based, or geodetic coordinates (EFG coordinates). The
next three values (with "dot" denoting the time derivative) are the
corresponding velocity components.
The NASA Earth Fixed Greenwich - EFG coordinate system rotates with the
earth (hence it is not inertial or fixed in space, but undergoes
motion). The velocities in this coordinate system are reduced by the
rotational velocity of the earth.
State Vectors can be use in place of
as a source of information for the
in WinOrbit. See the discussion of
State Vectors can be displayed from the Map Window