A planet shattered a thousand years ago in the final battle between the Menthars and the Promellians, leaving an asteroid field still seeded with energy-draining traps.
Orelious IX was a planet destroyed in the last engagement of the war between the Menthars and the Promellians, a conflict that wiped out both peoples about a thousand years before the 24th century. Its remains are the setting of the third-season Next Generation episode Booby Trap.
In 2366 the Enterprise-D arrives to survey the rubble and picks up a distress call from an intact Promellian battle cruiser, the Cleponji. Picard, delighted, leads an away team to the ancient ship. Soon afterwards the Enterprise finds itself losing power and being bombarded with radiation.
The Menthars had laced the debris with aceton assimilators, which absorb a ship's energy and turn it back as lethal radiation. La Forge, working with a holodeck recreation of the engine designer Leah Brahms, finds a way to coast out with minimal power, and the Cleponji is then destroyed.