Orbital state vectors

In astrodynamics and celestial dynamics, the orbital state vectors (sometimes state vectors) of an orbit are Cartesian vectors of position (${\displaystyle \mathbf {r} }$) and velocity (${\displaystyle \mathbf {v} }$) that together with their time (epoch) (${\displaystyle t}$) uniquely determine the trajectory of the orbiting body in space.^[1]: 154

Orbital state vectors come in many forms including the traditional Position-Velocity vectors, Two-line element set (TLE), and Vector Covariance Matrix (VCM).