The celestial clock is a model of an unknown solar system, which can be found in Save Station B, outside of Botanica. Created by the Chozo, it is stated as being made after a specific solar system, though one that does not match any profiles in the GF databank.
Though only a theory, it could represent the Chozo's home solar system. This solar system has a yellow sun, at least 3 planets, the second which has one moon (that rotates erratically) while the third has three, and what appears to be a large asteroid belt at its fringe and what may possibly be a fourth planet.
From Matt Manchester:
"I always loved the feel of the save stations in prime[sic]. I thinks[sic] its the immediate sense of comfort and safety you feel when entering one. I wanted push that feeling that I always got, and make a very serene little hideaway type of save station. Along the walls, I made celestial clocks, that correspond to some unknown solar system, and the respective orbits of their planets."
"This Chozo model appears to represent a specific solar system. No profile matches in data bank."
Federation Solar System | Gaflar System | Kalandor region | Messina System
Milky Way Galaxy | Small star | SR388's solar system | Sun | Tetra Galaxy | Unknown Solar System Unidentified Solar System 2