Whether the world is celebrating the 50th anniversary of the lunar landing or looking forward to a return to the lunar surface with the NASA-led Gateway, there's a lot of focus on the moon these days. And that's a good thing, because, let's face it, going to the Moon is pretty exciting and is a necessary precursor to a human mission to Mars. We have a lot to learn along the way, and one place to start is with the orbit.

Artist’s concept of the NASA-led Gateway. Image: NASA

Maxar is a leader in designing and building communication satellites that reside in geosynchronous orbit (GEO) and imaging satellites that call Low Earth Orbit (LEO) home. But now it's time to take a look at a new neighborhood: Near Rectilinear Halo Orbit (NRHO). The NRHO is a highly inclined orbit around the moon and is considered to be in cislunar space. Cislunar is Latin for "on this side of the moon" and generally refers to the volume between Earth and the moon. Cislunar space includes LEO, Medium Earth Orbit, GEO, as well as other orbits, such as Low Lunar Orbit and NRHO, the intended orbit for the Gateway. The NRHO is a seven-day cycle, taking the Gateway as close as approximately 1,600 km (1,000 miles) and as far away as about 68,260 km (42,415 miles) from the lunar surface. Consequently, roughly every seven days, the lunar lander can depart the Gateway to travel to the lunar surface. Because the Gateway can sit in this halo orbit, almost like it’s held in place by the gravity of Earth and the moon, it requires little energy for stationkeeping or to maneuver into other cislunar orbits. The orbit is called a "halo" orbit because the tracked orbit looks like a halo around the moon.