The Eightfold Stars were an octonary star system consisting of eight stars that were moved into orbit around each other some 200,000 to 300,000 years ago by an ancient civilization. In the middle of them, they placed the planet Aia, which contained the Admonition. (PIC: "Broken Pieces")
Hundreds of years before the 24th century, a group of Romulans came to investigate the mystery of the Eightfold Stars. They found the Admonition, and thus formed the Zhat Vash. Some ancient Romulan star atlases showed an octonary system, but it was considered apocryphal as it did not appear on their modern charts.
In the wake of the Attack on Mars in 2385, Raffi Musiker became obsessed with conspiracy theories surrounding the event, which involved the Conclave of Eight. At the time, she thought that they were a group of eight people. In 2399, after seeing drawings of an octonary made by Romulan xBs on the Artifact Musiker, with the help of Enoch, surmised that the group could have been named after their meeting place instead of their members. She surmised that the creators of the Eightfold Stars used it to draw attention to their warning. (PIC: "Stardust City Rag", "Broken Pieces")