The inhabitants of Gamelan V, who call on the Enterprise for help when a derelict barge full of radioactive waste enters orbit and begins poisoning their atmosphere.
The Gamelans are the people of Gamelan V, seen in the Next Generation episode Final Mission. In 2367 their leader, Chairman Songi, sends out a distress call after an unidentified vessel takes up orbit around her world and radiation levels in the atmosphere begin to climb sharply.
The ship proves to be an old, unpowered garbage scow loaded with unstable radioactive waste. The Gamelans have no means of moving it, so Riker, commanding the Enterprise while Picard is away, decides to tow it through the system's asteroid belt and release it into the sun.
The job exposes the crew to dangerous doses of radiation and keeps the Enterprise from searching for the mining shuttle carrying Picard and Wesley Crusher, which has crashed on a desert moon. The barge is finally cast loose with only minutes to spare.