A few more of the flags that can be found in Dee's native solar system.
Top Left: Cultural flag of Canadian colonies. Based on the standard Canadian flag, but with the maple leaf replaced by a maple key (seed). Represents Canadian people and culture, rather than the Canadian state and government.
Middle Left: Civil flag of Phobos. Based on the classic Red Ensign design used by many British-descended polities. The main field is black to represent space, rather than the colors representing sea, land, or air. The ancestral flag in chief has just been described. The logo on the fly is the astrological symbol for Phobos. This flag represents the civil government of Phobos, which runs things in the name of the King Sleeping Under the Mountain; the self-proclaimed monarch is currently in cryonic suspension while a cure is sought for a terminal illness.
Middle Right: Personal sigil of Phobos' King.
Bottom Left: Flag of the colony on Eichsfeldia, which is German for 'Oakfield'.