The Aphelion

It's from the Greek, "apo" meaning away from and "helios" meaning the sun. Aphelion means the point of orbit furthest from the sun. 

Here, it doesn't mean the Sun we see but as stars in general. Because stars are the main source of light for planets, the name suggests these "people" are rarely seen/witnessed (like the dark side of the moon). The rare accounts/records are myth-like tales from around the galaxy that share certain striking similarities. The greek words also makes it sounds like astronomy because that is where we get clues/hints of their existence

Their mark on the history was never more than eerie stories that are ubiquitous to different (major/minor?) cultures in the galaxy, until now. A faction of hidden intentions have opened their channels for communication and claimed to be the the Aphelion of old myths.  Though ambiguous in motivations, their resourcefulness/prowess (in the field of espionage?) ensure their validity (in the politcal scene?) on the galactic scale. 

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Ok, "validity" is kinda strange choice. Maybe some words relating to politics would be better to describe them.