question:  How do moon inhabitants tell the time of day?
context: The light from the star that died when the meteor was created fell on Earth before the first lungfish ventured from the sea. In its last instant, the meteor fell on the Moon. It was two days to sunrise, where Evans stood. It was just before sunset on a spring evening in September in Sydney. The shadow line between day and night could be seen from the Moon to be drifting across Australia. Evans, who had no watch, thought of the time as a quarter after Australia. It was three days' supply of water, if it had been carefully used. The stars next to the sun shone as brightly as though there were no sun. They might have appeared to waver slightly, if they were behind outflung corona flares. This was to allow the air-conditioning system to function properly, and to prevent air loss in case of the highly improbable meteor damage. For example, because of an order of his stating that there would be no alcoholic beverages within the survey building, the entire survey was assured of a constant supply of home-made, but passably good liquor. Morning to Mrs. Garth was simply the first four hours after waking. Morning to him had no meaning at all, but he thought in the strictest sense that it would be morning on the Moon for another week. The solar furnace was a rough parabola of mirrors used to focus the sun's heat on anything that it was desirable to heat. It was used mostly, from sun-up to sun-down, to supplement the nuclear power plant. Three of the nine banks of mirrors would not respond to the electric controls, and one bank moved so jerkily that it could not be focused, and it threatened to tear several of the mirrors loose. "Meteor shower," Cowalczk answered, "and that's not half of it. All of 'em too small for Radar to pick up, and not enough for Seismo to get a rumble." "That could hurt," Cowalczk admitted, "but there was only one of them."
output:  Identifying the shadow line as it relates to Earth's continents
options:  Identifying the shadow line as it relates to Earth's continents  Identifying the shadow line as it relates to the moon's time zones  Identifying the shadow line as it relates to the moon's continents  Identifying the shadow line as it relates to the Earth's time zones