The Graveyard of Space by Milton Lesser, Science Fiction, Adventure, Fantasy (Paperback)

Nobody knew very much about the Sargasso area of the void; only one thing was certain: if a ship was caught there it was doomed in the graveyard of space. But Ralph Meeker and his wife Diane were going there. Whether they intended to or not. It was just what you'd expect, wasn't it, the way their luck had been lately. The asteroid mine had been a bust, utterly and entirely. God knew what they were heading home to. Divorce, probably. Poverty. And now the used spaceship's guidance was sending them into the part of the asteroid belt nobody "ever" came out of. . . .