Minor-planet moon Herculina does not have a significant satellite. There were other similar reports of asteroids having companions (usually referred to as satellites) in the following years. Also, a letter in "Sky & Telescope" magazine at this time pointed to apparently simultaneous impact craters on Earth (for example, the Clearwater Lakes in Quebec), suggesting that these craters were caused by pairs of gravitationally-bound objects. In 1993, the first asteroid moon was confirmed when the Galileo probe discovered the small Dactyl orbiting 243 Ida in the asteroid belt. The second was discovered around 45 Eugenia in 1998. In 2001, 617 Patroclus and its
City on the Moon City on the Moon City on the Moon is a science fiction novel by Murray Leinster. It was released in 1958 by Ace Books under authority from Thomas Bouregy & Co using their Ace Double imprint reference number D-277. The novel details the events that unfold subsequent to an apparent sabotage attempt made against a lunar jeep on its return journey to the multinational civilian lunar city. This story was first published by Avalon Books in 1957. "City on the Moon" forms part of the To the Stars series by the same author, with two preceding books being "Space Platform"