The dream of a human habitat in orbit about the moon came a step closer on September 27, when NASA and the Russian space agency (Roscosmos) signed up to a common vision for future human exploration. The project, a follow-up to the International Space Station (ISS), involves a facility placed in orbit somewhere between the Earth and the moon – a region known as cis-lunar space. Seen as a stepping-stone on the way to deeper space exploration, it has been dubbed the Deep Space Gateway, DSG.