Risa, also known as Epsilon Ceti, were binary suns in the Alpha Quadrant. The planet Risa orbited these stars.
In 2256, these stars' location was labeled on the star chart "Alpha/Beta Quadrant Overview" in the ready room aboard the USS Discovery. (DIS: "Magic to Make the Sanest Man Go Mad")
In 2257, during the first Federation-Klingon War, these stars' system was occupied by the Klingons. (DIS: "The War Without, The War Within")
According to Star Trek: Star Charts (p. 62) and Stellar Cartography: The Starfleet Reference Library ("Federation Historical Highlights, 2161-2385"), Risa (Epsilon Ceti) was a multi-star with a trio of F-class stars.
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