A remote Starfleet communications relay station staffed by a lone Denobulan officer, wrecked in 2384 when the Protostar's hidden weapon activated.
Relay Station CR-721 is a Starfleet communications outpost on the fringe of Federation space, seen in the Prodigy episode Asylum.
Dal and his friends arrive there in the USS Protostar hoping to hand themselves in and ask for asylum. The station's only crew member, the Denobulan Lieutenant Barniss Frex, welcomes them aboard and begins checking who they are.
Unknown to all of them the Protostar carries the living construct, a weapon designed to turn Starfleet systems against one another. Once it links with the station it sends the outpost's systems haywire and the station breaks up. Frex gets away in an escape pod, and the young crew flee, now aware of the danger their ship poses.