The Legendary MechanicTranscendental Mechanic • 超神机械师

The story uses unusual terms to describe galactic scales, like star zone, star system, star cluster, star field. I suspect this is because the translator doesn't know the real terms for these scales or got confused by the author's choice of wording. I believe I have a proper understanding of what these terms actually mean:

Planetary - a planet

Star Zone - a solar system
One or more stars orbiting each other with zero or more planets orbiting them.

Star System - a galaxy
E.g. the Milky Way or Andromeda galaxies.

Star Cluster - a galaxy cluster
Multiple galaxies close enough together that they are gravitationally bound. Our Milky Way galaxy is in a cluster with Andromeda as well as around 30 other smaller galaxies. This cluster is often referred to as the "local group".

Star Field - a galaxy supercluster
Look at the universe at a large enough scale and you'll see large sections of space filled with galaxies; you'll also see much, much larger sections surrounding these groups that are almost completely empty. The massive clumped groups of galaxies are called superclusters. Our own galaxy is in the Virgo Supercluster.

His relationship with Ames is infuriating, and they only become lovers towards the last 100 chapters.