Abstract

Due to the nature of their orientation with respect to the line-of-sight to Earth, jets of gas leaving energetic sources occasionally have the appearance of moving faster than light when viewed from the Earth. While the inferred velocities of such jets with respect to their source, calculated under the tenets of SRT, are less than c, they are still very close to c. However, certain orientations require that, under the assumptions of SRT, the jets must have a velocity with respect to their source which exceeds c. Under models other than SRT, the velocities required under these same configurations remain less than c. Studying such jets throughout the cosmos presents a great test for Einstein?s second postulate, since there may indeed be jets who?s orientation to the line-of sight imply, under SRT, an inferred speed with respect to their source in excess of c. Even considering configurations already observed, a comparison of the energy required to produce jets at speeds approaching c under SRT (including relativistic mass increase) to the energy available from the source should provide a strong test of SRT.