Polaris is located over Earth's axis of rotation, hence, the reference point for earth's latitude system.

I can not find any reference to a Meridian in the Solar System.

In astronomy, there is the Earth's meridian. That's a "great circle" on the "celestial sphere". It passes through the "celestial poles" and also through the "zenith" at the observer's location.

The Space Station is no a celestial body. Celestial bodies are natural -- not man made.

The celestial coordinate system is exactly analogous to the terrestrial positioning system

based on latitude and longitude.

Terrestrial latitude ---> celestial 'declination'.

Terrestrial longitude ---> celestial 'right ascension', where one 'hour' = 15 degrees.

Celestial navigation.