NASA is going back to the Moon and it won't just be a flying visit. The space agency is planning to begin the testing of new landers by 2024 and aims to have a crew on the surface by 2028. And this time, we'll be there to stay.

The agency is inviting private companies to submit ideas on the best ways to land astronauts on the Moon, as well as developing other key technologies that could be used on our natural satellite, and finding the best ways for transferring people and items to and from there. The approach NASA is taking is similar to the collaborations between the agency and private companies for technological development in low-Earth orbit.  

“Building on our model in low-Earth orbit, we’ll expand our partnerships with industry and other nations to explore the Moon and advance our missions to farther destinations such as Mars, with America leading the way,” NASA Administrator Jim Bridenstine said in a statement. “When we send astronauts to the surface of the Moon in the next decade, it will be in a sustainable fashion.”

The plan as it stands has four major steps to bring astronauts back to the Moon. NASA needs a crewed launch vehicle. Some are already being developed by private companies to bring humans to the International Space Station (ISS). But to go from the ISS to the Moon, you need a lot of power. Possibly new approaches will be devised but there’s also the SLS, the Space Launch System, developed by NASA to take humans into deep space.

Whichever launch system is used, astronauts won’t go directly to the Moon’s surface. NASA is planning to build the Gateway, an automated spaceship orbiting the Moon. It will not be continuously inhabited like the ISS, but teams will stay there and will conduct short stays and trips to the surface of the Moon.

To go to the Moon and back, it is necessary to have a lander. NASA is looking for proposals that will hopefully achieve a completely reusable lander. Fuel also needs to be considered. Initially, it could use fuel brought over from Earth, but NASA is also interested in technology to produce fuel directly from lunar soil and water.

NASA has published a formal request of proposals and responses are due on March 25. We'll update you when we know more.