1. I understand that it is impossible to say if something is absolutely stationary, for example wrt the universe, and that there is no such thing as absolute movement now 2. if you place a point source of light at the origin, “O”, of a Cartesian coordinate system. At t1 the point source of light simultaneously releases a single photon along the x,y and z axis. 3. After a short time say t2 you simultaneously measure the distance from the origin to the photons on the x,y and z axis. 4. As the speed of light is the same in all frames of reference if the distance to all three photons is the same then you can conclude that the point source of light is absolutely stationary. Is that right? 5. Is this explanation the definition of absolutely stationary? 6. If you conclude that the point source of light is absolutely stationary then anything moving relative to the point source of light is not relative movement but absolute movement is that right?