There are two main approaches that humanity can take to living in space. The one more commonly portrayed is of us colonizing other celestial bodies such as the Moon and Mars. That approach comes with some major disadvantages, including dealing with toxic soils, clingy dust, and gravity wells.
The alternative is to build our own habitats. These could be located anywhere in the solar system, could be of any size that material science allows, and have different characteristics, such as temperature, climate, gravity, and even lengths of day. Unfortunately, we are still a very long way from building anything like a fully sized habitat. However, we are now one step closer to doing so with the release of a paper from a team at Texas A&M that describes a way to build an expandable space habitat of concentric cylinders that can house up to 8000 people.
Every year, the NASA Innovative Advanced Concepts (NIAC) program puts out the call to the general public, hoping to find better or entirely new aerospace architectures, systems, or mission ideas. As part of the Space Technology Mission Directorate, this program has been in operation since 1998, serving as a high-level entry point to entrepreneurs, innovators and researchers who want to contribute to human space exploration.
This year, thirteen concepts were chosen for Phase I of the NIAC program, ranging from reprogrammed microorganisms for Mars, a two-dimensional spacecraft that could de-orbit space debris, an analog rover for extreme environments, a robot that turn asteroids into spacecraft, and a next-generation exoplanet hunter. These proposals were awarded $100,000 each for a nine month period to assess the feasibility of their concept.