 How do moon inhabitants tell the time of day?
The light from the star that died when the meteor was created fell on Earth before the first lungfish ventured from the sea. 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. 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. After the sun rose, Evans returned to the lava cave that he had been exploring when the meteor hit. All of these needed water to form, and their existence on the Moon puzzled him for a while. The sun rose to the meridian slowly. The stars shone coldly, and wheeled in their slow course with the sun. The shadow line crept around until Earth was nearly dark, and then the rim of light appeared on the opposite side. For a while Earth was a dark disk in a thin halo, and then the light came to be a crescent, and the line of dawn began to move around Earth. The continents drifted across the dark disk and into the crescent. The people on Earth saw the full moon set about the same time that the sun rose. He made trips from and to the Moon about once a month, carrying supplies in and metal and ores out. That's from here to Earth, of course.
 Identifying the shadow line as it relates to Earth's continents
 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