Though space hotels have long belonged only to the world of make-believe, that's about to change. NASA says it will open the International Space Station (ISS) to tourists as early as 2020.

Private companies are redefining space exploration with ambitious plans for orbital hotels, medical labs, and even lunar ...

The Gateway Foundation has announced that it intends to open the world's first space hotel, named Voyager Station, in 2027.

The first commercial space hotel will be more like a cruise ship than Stanley Kubrick's sleek space station from 2001, says Tim Alatorre, senior design architect of the Von Braun Space Station.

A startup called Orion Span is aiming to launch a luxury space hotel, dubbed Aurora Station, into orbit by 2022. A stay would cost $9.5 million per person.