As part of the continued interest in pursuing human space exploration, NASA is spearheading the development of the Lunar Gateway (Figure 1) – a new, sustainable, space station in orbit around the Moon. This 40-tonne spacecraft will mark the first major international collaboration in space exploration technology since the launch of the International Space Station (ISS) in 2000. The Gateway will not only provide easier access to the lunar surface – due to its near-rectilinear halo orbit which at points brings the station within 1,000 km of the Moon – but it will act as a staging point for future missions to Mars and beyond in keeping with NASA’s primary mission of sending humans into deep space.
Figure 1: The Gateway will serve as a staging point for future lunar and deep space missions (NASA, 2020)
The proposed Gateway space station is intended to serve as a short-term habitat for astronauts as well as a mission control centre for expeditions of the lunar surface and a space for scientific research and the stockpiling of essential supplies. Preliminary component construction is underway and in-space assembly has been suggested to begin in or around 2023 with NASA contributing the first two modules: the Power and Propulsion Element – for supplying power, basic communications and attitude control – and the Habitation and Logistics Outpost (HALO) – the initial crew cabin for visiting astronauts – at the approximate cost of $820 million. Other contributions to the Gateway including advanced external robotics, advanced communications and modules for further habitation, logistics, storage and research will be developed post-2023 and will be supplied by the current ISS partner nations (i.e. United States, Canada, Europe, Japan and Russia), as detailed in Figure 2.
Similar to the development of the ISS, the individual components for the station will be constructed in stages on Earth and assembled in space. Unlike the ISS, which has continuously seen a human crew for the past 20 years, the Gateway will only be able to support astronauts for a period of up to 90 days. These periods are likely to coincide around future lunar surface missions or launches to Mars or deep space. In times where human crews are absent, the development of advanced robotics and artificial intelligence systems, primarily supplied by Canada, will be poised to operate the station. Once completed, the Gateway will act as a science laboratory, a test site for new and developing technology, and a stepping-stone for expeditions to the Moon and to Mars.
Figure 2: Breakdown of the Gateway components contributed by international partners (NASA, 2020)
Constructing an orbital station around the Moon offers many benefits including a more in-depth exploration of the effects of cosmic and solar radiation beyond the protection of Earth’s magnetic field, an easier access and landing cycle for launch vehicles to the lunar surface, a new and unique setting for research and technology outside the ISS, and new perspectives for observing the Sun, the Earth and deep space.
In terms of explorations of the lunar surface, the station would be able to act as a sort of “spaceport” for lunar landers or small spacecraft destined for the Moon. Human crews traveling to the Moon would be able to dock at the Gateway using the Orion Crew Module (Figure 2) and transfer to a lunar landing vehicle already attached to the station. This approach would reduce costs of launches and developments of new lunar landers for each subsequent lunar mission. In terms of deep space missions, human crews would be able to dock with the Gateway to acquire mission supplies. This would decrease costs of launching deep space missions due to not launching cargo and crew, thus having a decreased mass. Further, once crews have acquired supplies, the Gateway would provide for a lower fuel need as spacecraft would be able to use the gravitational pull of the Moon to gain necessary mission velocity rather than the use of thrusters before continuing traveling into deep space.
On paper, the Gateway looks like a prime concept in terms of international collaboration and its benefits to future lunar and deep space missions, especially NASA’s Artemis missions which aim to land humans on the Moon again in 2024. But in recent months, the development of the Gateway has been met with some degree of controversy. Plans for the Gateway were initially introduced as a key support element for the 2024 lunar landing stating it as part of the “critical path” for returning humans to the Moon. But as of March 2020, Doug Loverro, the former head of NASA’s human spaceflight directorate, announced that the Gateway has been removed from the scheduled Artemis missions. The reasons are warranted, including favouring simpler designs and solutions for the first lunar return since 1972, a “de-risking” of the Artemis program by omitting activities of unknown effect and risk, and the likely possibility that construction on the Gateway will fall behind schedule. Additionally, the development of the initial Gateway modules have already exceeded preliminary cost estimates with NASA’s $375 million Power and Propulsion module already seeing a pre-development spike.
Figure 3. NASA’s 50-kilowatt solar electric Power and Propulsion Element (NASA, 2020).
In light of these occurrences, some concern has arisen in regard to the continued relevance of the Gateway project. The upcoming Artemis missions will land humans on the Moon without the assistance of the Gateway and the recent triple launch to Mars in July 2020 from three separate nations proves it is possible to send launches into deep space without the Gateway’s involvement. But aerospace analysts like Jeff Foust have commented on the difficulties the Gateway is facing in terms of sped-up deadlines, international collaboration, and a reorganization of costs in the US 2020 fiscal budget proposal while space journalists like Eric R. Hedman have commented on the tilting scales of pros and cons including safety, SLS/Orion launchers, fueling and power, and the role of international partners especially in terms of national budgets.
Those concerns, however, paired with the knowledge that the Gateway is an enormous undertaking of international scale, NASA is continuing forward with its plans to develop a lunar orbital space station. Though the initial purpose in aiding the Artemis missions has changed, it is possible the Gateway could still have a positive effect on future lunar exploration once construction and assembly has been completed. Likewise, while lunar and deep space missions can continue without an international lunar station, the benefits to research, exploration and future cost savings that the Gateway proposes could in time potentially change the future of space exploration and open doors to future deep space destinations.
– Evan Cook
About the Author:
Evan has a master’s degree in creative writing from the University of Surrey and a bachelor’s degree in fine arts from the University of South Carolina – Aiken. He is currently studying at the International Space University pursuing a career in space journalism and communications outreach. He is an award-winning author, playwright and filmmaker.