After half a century, there is a commercial market for Moon missions

“THE MOON is a Harsh Mistress”, by Robert Heinlein, was not just the most influential novel about the Moon published in the 20th century. It was also the one with the raciest title. In the body of the book, though, the Moon’s role is less dominatrix, more docent: what Professor Bernado de la Paz actually says in the speech from which the title-words stem is that the Moon “is a stern schoolmistress” who teaches “harsh lessons”. And this, it seems, is true.The latest pupils to walk out of one of her tests with only a new crater to show for it are the team at ispace, a Japanese company, which tried, and failed, to land on the edge of on April 25th. The spacecraft, launched last December, had performed nicely as it took a slow, energy efficient trajectory out to the Moon, inserted itself into orbit, and adjusted that orbit until it was circling at 100km just as intended. On the final journey from orbit to surface, though, its engine cut out a little too early and it plummeted to the surface.