Fusion candle technology is used to produce thrust, heat and light to Jovian or Neptunian gas giants.
Fusion candles are massive fusion-powered thrusters which are suspended in the atmosphere of the planet. They suck in atmospheric material like hydrogen or helium isotopes and use it as propellant to apply a direct force on the planet. They are used in the atmosphere of unpopulated worlds, their moons and anything else in orbit with them.
Fusion candles can also provide heating and illumination to a dark world or its moons. They can also be used in mining operations and planet lifting.