The Bre'el IV moon, also known as the Bre'el satellite, was the asteroidal moon of Bre'el IV. The moon had a minimum orbit distance of 50,032 kilometers, a maximum distance of 50,059 kilometers, a mean orbital inclination of 0.025 degrees, and an average orbital period of 746 minutes.
In 2366, the moon began to fall out of orbit, threatening the planet. Q theorized that this was caused by a large celestial object passing at near right angles to the plane of the star system, likely a black hole. The USS Enterprise-D made several attempts to return the moon to its proper orbit, but was unable to do so. Disaster was ultimately averted by Q when he returned the moon to its proper placement. (TNG: "Deja Q")