Now the time is half past eight in the morning in the Ruins World—of course, this time was converted. People on this planet are not accustomed to the twenty-four-hour system. However, Big Sister and the others unanimously agreed that a thirty-hour day was simply too much, so we converted the time here to Earth's standard time system.
Under normal circumstances, daytime in the Ruins World starts at six o'clock in the morning. Every morning, the central time station of the "Great City" broadcasts the standard time to the entire Ruins World. Then, the maintenance workers of the Sun Furnace will restart all the Fusion Reactors above the planet. Those reactors, which have been operating at low power throughout the night, take thirty minutes to fully restore power. By half-past six, bright "sunlight" illuminates the land, marking the start of a new day in the Ruins World.
But this is only under normal conditions.