 What motivates Pop Young to live on the far side of the moon?
Once in two weeks Earth-time a rocketship came around the horizon from Lunar City with stores for the colony deep underground. When it was first found, scientists descended into it to examine the exposed rock-strata and learn the history of the Moon before its craters were made. There were air-tight bulkheads for safety, and a hydroponic garden to keep the air fresh, and all sorts of things to make life possible for men under if not on the Moon. In the Moon's slight gravity, a man is really adjusted to existence when he has a well-developed case of agoraphobia. With such an aid, a man can get into a tiny, coffinlike cubbyhole, and feel solidity above and below and around him, and happily tell himself that it feels delicious. He'd shipped out, whimpering, to the Moon to get far away from Pop, and Pop was just about a mile overhead and there was no way to get around him. All of which happened back on Earth and a long time ago. There was a warning-bell in the shack, and when a rocketship from Lunar City got above the horizon and could send a tight beam, the gong clanged loudly, and Pop got into a vacuum-suit and went out the air lock. Most men immediately found it hysterically necessary to seize hold of something solid to keep from falling upward.
 He is close to Sattell's location, which enhances his memories of his wife and children
 He is being compensated for a wrongful death suit that occurred back on Earth  He is close to Sattell's location, which enhances his memories of his wife and children  If he left his post, there would be no one to monitor the mines in the Big Crack  If he returned to Earth, he would be arrested for the murder of his family