Weird physics question - relativistic immobility

[Kuciwalker]

So, if we were or became a spacefaring people, we would have no fixed reference for speed regarding ships travelling from solar system to solar system?

Sure we would. We can arbitrarily pick e.g. "The Sun" as our fixed reference*.

*technically the Sun is accelerating (as it's in orbit around the galactic center) but depending the scale of space travel that's not a big deal

Most science fiction appears to gloss this over despite the relativity theories being older than the sci-fi genre.

Most sci-fi completely ignores relativity by introducing FTL.

[KrazyHorse]

So, if we were or became a spacefaring people, we would have no fixed reference for speed regarding ships travelling from solar system to solar system? This would make interception of ships or objects not in the f.o.v. a real *****. To say nothing of occupant aging anomalies when comparing those on high speed ships vice those on the departure or arrival planets. Most science fiction appears to gloss this over despite the relativity theories being older than the sci-fi genre.

???

1) Pick a f.o.r. Say, the center of the galaxy. Or some local object which is really bright

2) Stick with it. All positions and velocities are to be measured in the f.o.r. given in (1)

This is no different than choosing a coordinate system on the Earth's surface (latitude/longitude)