According to the theory of special relativity it IS possible to view two objects moving faster than the speed of light relative to each other. You may think this is not the case but, let me explain. I saw this get confused in a lemmy thread and wasn't setup to post there so I'll clarify here for the interested.
Consider the following: observer A sees a craft B moving right at 0.6c, and another craft D moving left at 0.6c such that they are on a collision course.
B------> <------D
A
what I'm asserting is A does observe B and D moving at 1.2c relative to each other. The Lorenz transformation is not needed! People get tripped up, but the setup gives away the answer. A sees nothing moving faster than c relative to A so there is no violation of theory.
Special relativity becomes relevant here when determing what is observed in reference frames other than ones own, i.e. B or D. Based on what A sees, it seems like B should see D moving at 1.2c , but applying the lorenz transformation to get B's perspective we see that it doesn't, and everything is seen as slower than c.
B observes A moving at 0.6c, and D at something like, idk, 0.85c (length contraction along the axis of travel is especially relevant here).
B <---------D
<------A
Just as easily this setup could involve objects moving away from each other and could represent distant objects being pushed away from eachother by the expansion of the universe. The neat thing there is that once they're far enough to cross the horizon above c, they'll never see each other because the light isn't fast enough to cross the gap, so conventiently a violation still isn't observed! 
https://en.wikipedia.org/wiki/Observable_universe
light emitted by objects currently situated beyond a certain comoving distance (currently about 19 gigaparsecs (62 Gly)) will never reach Earth.