The picture depicts the transit (motion across the sun) of the principle chapter monastery of the Knights of the Sun.

The fact the principle chapter is an orbital colony located very close to the yinrih’s home star is where the Knights got their name.

In Commonthroat knights are called rGHqg, related to rGHg, meaning “mech” or “heavy armor”. The organizational unit that has a local presence in a particular city is called an rGHlNg, meaning “armory” or “mech hangar”. The local leader is simply “the head knight” or “head of the armory” but humans usually refer to the place as a “chapter” and to the local leader as a “chaptermaster”, mostly because the Knights are warrior monks in powered armor, evoking comparisons in-universe to a certain grimdark tabletop game. The knights, for their part, find these comparisons offensive given they actually like aliens.