Captain Silva La Forge's ship, which vanished with all hands in 2370.
The USS Hera was a Starfleet starship commanded by Captain Silva La Forge, the mother of Geordi La Forge. In 2370 the Hera disappeared with all hands while on a routine mission.
Shortly afterwards, Geordi used a probe interface to explore the trapped USS Raman in the atmosphere of Marijne VII and encountered what seemed to be his mother, who claimed the Hera was trapped there. The figure was actually a lifeform from the planet's atmosphere trying to return home, and after helping it, Geordi had to accept that the Hera's fate remained unknown.