The second term, however, which contains information about the acceleration and other unique behavior of the charge that cannot be removed by changing the Lorentz frame ( inertial reference frame of the observer ), is fully dependent for direction on the time-retarded position of the source.
12.
The front of the craft is in the \ acute { \ mathbf { x } } direction, and the \ acute { \ mathbf { y } } direction is to the left of the craft . The spacecraft is small compared with the size of the orbit so that the local frame is a local Lorentz frame.
