Related Clues:

• Acronym for sky watchers
• Goes downhill?
• Abductees' destinations, in some hard-to-believe stories
• Supposed alien craft
• British diplomats in America — they're out of this world!
• Supposed spaceships
• Space travellers start unusual fiction output scientifically
• Vehicles with no-wheel drive
• Bobrun runners
• Sci-fi transports
• "Did I just see that?" things
• On the contrary initially, slice top off tofu as that lot come with their own saucers
• Dog-powered vehicles
• Initially, they're thought by some to come from outer space
• Mysterious objects in sky