Superluminal Motion in the Jet of M87

This animation illustrates superluminal motion in the optical jet of the active galaxy M87. The top diagram shows the motion in the inner part of the jet from 1994 through 1998. The bottom diagram illustrates that the knot in the jet marked by the arrow in the upper animation appears to move 24 light years in just 4 years, implying an apparent velocity of 6 c. This is an illusion caused by a relativistic jet pointed nearly in our direction. In reality the velocity of the jet never exceeds the velocity of light. Usage: Click "Play" to begin. "Step" moves forward one step and "Back" moves backwards one step. "Home" returns to the beginning from any point.