In October of 2024, NASA will send “the first woman and the next man” to the Moon as part of the Artemis Program. This will be the first crewed mission to the lunar surface, and the first mission beyond Low Earth Orbit (LEO), since the closing of the Apollo Era in 1972. Beyond that, NASA plans to establish infrastructure on and around the Moon that will allow for “sustained lunar exploration and development.”
A key aspect of this is the Lunar Gateway, an orbiting habitat that will allow astronauts to make regular trips to and from the lunar surface. After much consideration, NASA recently announced that they have selected SpaceX to launch the foundational elements of the Gateway – the Power and Propulsion Element (PPE) and the Habitation and Logistics Outpost (HALO) – by May of 2024 (at the earliest).
Originally, NASA planned to deploy the Gateway before they sent astronauts back to the surface of the Moon (as part of the Artemis III mission). In this scenario, the crew would launch from Earth the Space Launch System (SLS) and Orion spacecraft and dock with the Gateway in lunar orbit. The long-awaited return to the surface (and all subsequent surface missions) would be accomplished by means of a reusable lunar lander.
Unfortunately, these plans had to be altered to accommodate the expediting schedule introduced by the Trump administration. With October of 2024 established as the deadline for Artemis III, NASA was forced to de-prioritize the Lunar Gateway and consider other options. This consisted of enlisting private contractors to develop a Human Landing System (HLS) that could be integrated with the Orion spacecraft (and later, the Gateway later).
At the same time, NASA considered deploying the Gateway independently of the early Artemis missions and using the SLS to deploy the PPE and HALO elements seperately. Another possibility was to enlist the help of a commercial launch provider to deploy the Gateway, thus freeing NASA and the SLS up to focus on mounting the crewed Artemis missions.
According to a recent announcement, NASA has signed a ~$331.8 million contract with SpaceX to launch the PPE and HALO elements together as early as May 2024. After these modules are integrated on Earth, they will be launched aboard a single Falcon Heavy rocket from Launch Complex 39A at NASA’s Kennedy Space Center.
Once the Gateway is up and running, the PPE element will provide power (in the 60-kilowatt), high-speed communications, attitude control, and Solar-Electric Propulsion (SEP) capabilities. This will allow it to alter its lunar orbit as needed, giving crews greater access to the lunar surface than was ever possible with conventional missions.
The HALO element will serve as the docking hub and the living/working quarters for crews visiting the Gateway (often on their way to the lunar surface). It will also act as the command and control module, support science investigations, distribute power, provide communications with visiting vehicles and surface expeditions, and also supplement the Orion spacecraft’s life support systems.
While neither NASA nor the Biden administration has indicated if it once again plans to use Gateway for Artemis III, the timing would seem to suggest that much. Barring any delays, the core of the Gateway will be in place five months before Artemis III launches. With the addition of a lunar lander, the Artemis III crew will no longer be forced to bring an HLS with them (saving on the overall mass of the mission).
Over time, additional elements will be added, like the European System Providing Refueling, Infrastructure and Telecommunications (ESPRIT) service module. This module will consist of the Halo Lunar Communication System (HLCS) and the ESPRIT Refueling Module (ERM), which will provide the Gateway with additional capacity for xenon and hydrazine fuel, additional communications equipment, and an airlock for science packages.
The HLCS will provide the communications for the mini-station and will be integrated with HALO ahead of its launch in 2024. The ERM will launch in 2027 and will provide ESPRIT’s pressurized fuel tanks, docking ports, and a small windowed habitation corridor. On January 7th, the ESA finalized a contract with French-Italian space manufacturer Thales Alenia Space worth $362 million (€296 million) to build ESPRIT.
Then there’s the International Habitation Module (I-HAB), for which Thales Alenia Space has been contracted, that will provide additional space for crews. This module is being developed by the ESA in collaboration with NASA, JAXA, and the Canadian Space Agency (CSA), which will be contributing the avionics and software, the a life support system, and robotics (respectively) and is slated to launch some time in 2026.
There are also a number of proposed modules that are still under consideration, but all planned modules are expected to be integrated and in orbit around the Moon by 2028. Once assembled, the Gateway will measure about one-sixth the size of the International Space Station (ISS) and will function as a way station located in cislunar space at Earth-Moon L1 Lagrange Point.
It will not only be an integral part of the Artemis Program, but also a hub for NASA and its international and commercial partners to conduct unprecedented lunar exploration and research. The Gateway will also play a vital role in the future exploration of Mars, serving as a way station for the Deep Space Transport and crews and cargo destined for the Red Planet.
Further Reading: NASA