Spoiler warning: Plot and/or ending details follow.
Yridia is a Federation planet, the homeworld of the Yridian species. It was located near a nebula that the Federation Starfleet referred to as the "Yridia Nebula." (ST reference: Star Charts, DSC episode: "Lethe")
The Rings of Paltriss were removed from Yridia over several years. (DS9 episode: "Melora")
In 2374, the Ariadne was travelling from Lissepia to Yridia when it was forced to detour to Deep Space 9. (DS9 novel: Hollow Men)
In 2381, Yridia was attacked by the Borg during their invasion, causing much destruction on the planet. (ST - Destiny novel: Lost Souls)