The mission to return to the moon and create an orbital gateway for deep space exploration just took a big step forward. NASA and the ESA have announced the orbit of the upcoming Lunar Orbital Platform-Gateway, a small space station capable of hosting crews for up to 30 days.

Unlike the International Space Station, which resides in low-Earth orbit, the Gateway will travel along what's called a near rectilinear halo orbit (NRHO), making close passes by the moon, but also looping far enough into space to remain in contact with NASA and receive maximum sunlight exposure for solar energy generation. That choice, which you can see in action in the video below, will affect landing and any number of other important scenarios.

In addition to the ESA, the U.S. space agency is also working with the space agencies Roscosmos (Russia), JAXA (Japan) and CSA (Canada).

Piece by piece

"In human spaceflight we don't fly one single, monolithic spacecraft," Florian Renk, mission analyst in ESOC’s Flight Dynamics Division, explained in an ESA news release.

"Instead we fly bits and pieces, putting parts together in space and soon on the surface of the Moon. Some parts we leave behind, some we bring back — the structures are forever evolving."

And the real beauty of the concept is that the project comes together in stages, allowing for smaller missions to set the stage for bigger ones.

In early 2019, NASA awarded the first contract for the creation of the Lunar Orbital Platform-Gateway's (LOP-G) 40kW power and propulsion elements and development of the station's habitation. Next in line are the logistics and airlock modules. Should all proceed according to plan, the power and propulsion piece will be placed into cislunar space sometime in 2022. Within three years, the complete platform should be ready to begin hosting four-person crews.

You can see Boeing's concept for the Gateway station and how it will ultimately aid the mission to land on Mars in the video below.

In a move reflecting the present diversity of space interests, the Gateway will be developed, serviced and utilized in collaboration with both commercial and international partners.

"It’s got fiscal realism, and it’s also adaptable," NASA associate administrator William Gerstenmaier told Bloomberg. "It can adapt to commercial partners. It’s not a rigid program of one mission following another."

An illustration of Phase 1 of NASA's mission to develop an orbiting lunar outpost. The first major component of the new station is expected to launch in 2022. (Photo: NASA)

Once complete, the Gateway is expected to provide invaluable insight on the lunar surface, support possible manned trips to the moon, and serve as a gateway for deep space crewed missions to planets like Mars. The halo orbit will create a natural pickup and drop-off window every seven days, when the Gateway is closest to the moon. That same orbit will also create a similar opportunity for deep-space missions.

"If we're ever to go to Mars, we have to learn how to operate far from the Earth," Dr. Richard Binzel, a planetary scientist at the Massachusetts Institute of Technology, told NBC News. "We need that operational experience. And I think that is the motivation for the Deep Space Gateway — to gain operational experience away from the comfort zone of low-Earth orbit."