midday
It was many times brighter than moonlight ever was upon the Earth . Even at lunar sunset the Earthlight was sixteen times brighter . At midnight , when the Earth was full , it would be bright enough for any activity . Actually , the human beings on Luna were nearly nocturnal in their habits , because it was easier to run moon-jeeps in frigidity and keep men and machines warm enough for functioning , than it was to protect them against the more-than-boiling heat of midday on the moon . So the activity about the salvaged space-ship increased . There were electric lights blazing in the demi-twilight , to guide freight vehicles with their loads . The tourist-jeeps went and returned and went and returned .