An ancient, unidentified freighter loaded with radioactive waste that drifts into orbit of Gamelan V in 2367, and which the Enterprise-D tows through an asteroid belt towards the system's sun.
The waste barge is the Enterprise's half of the Next Generation episode Final Mission. Chairman Songi of Gamelan V calls for help when an unknown vessel enters orbit and radiation levels on the planet begin to climb. The ship proves to be a very old, unmanned freighter packed with leaking radioactive waste, apparently abandoned by whoever filled it.
Riker, in command while Picard and Wesley Crusher are away on the mining shuttle Nenebek, decides to tow the hulk into the Gamelan sun. Remote thrusters fitted to it fail, so the Enterprise has to pull it with a tractor beam.
The route passes through an asteroid belt, which keeps the ship in tow far longer than planned while radiation exposure aboard rises towards lethal levels. Riker holds on until the barge is clear and then releases it to fall into the star.