Route 375, otherwise known as the Extraterrestrial Highway, passes by Area 51 and attracts tourists from across the world

On the northern edge of the Las Vegas sprawl where city meets desert, a vast building resembling a giant hangar stands among the suburban bungalows, occupying a 50-acre city block . This is the headquarters of Bigelow Aerospace, a company that plans to launch and sell its own space stations and, more ambitiously, build a space hotel and a lunar base. Recently, the hangar doors have remained closed and tumbleweed now blows across the car parks. The perimeter is fortified with razor wire and concrete barriers, and the only staff visible from outside are armed guards.

Neighbours in the neat residential streets say security was tightened at Bigelow Aerospace late last year when it was revealed that — incredible as it may sound — the