Two ships are traveling fairly close together side by side heading the same way on parallel paths near the speed of light [lets say v=.999C]. From the internal frame of reference [people in the ships] they can consider themselves as equivalent to being stationary, however from an external frame of reference [e.g. someone on a remote stationary point] we “see” length contraction of the ships, increased mass and time slowing down. I think I understand all of the above, please chime in with any corrections I might need, however, what I fail to understand is how the distance between the two ships will change over time. Since from an external frame of reference the two ships have greater mass then what explains the ships not being more gravitationally attracted to each other? Is it because there is also a time dilation? Do these two aspects cancel out [i.e. increased mass and increased time]?