NASA has committed itself to an ambitious goal: to once again land humans on the Moon. The Artemis Lunar Exploration Program, aptly named for its twin-like relationship to the Apollo missions, aims to not only return astronauts to the lunar surface, but to create a sustainable presence on and around the Moon. If successful, this will be the first time in history that humans would maintain a human presence on a foreign celestial body and would lay the groundwork for future deep-space travel in conjunction with NASA’s ultimate goal of bringing humans to Mars.
Figure 1: An artist’s rendering of astronauts on the Moon as part of the Artemis 3 mission. Photo Credit: NASA
First announced in July 2019, the Artemis program aims to land the next man and the first woman on the Moon in 2024 – the first time any human will have set foot on the lunar surface since Apollo 17 in 1972. The program will be divided into three separate missions set to take place across the next four years, culminating with the lunar landing as part of Artemis III. To this end, NASA is developing powerful, new deep-space exploration systems that will more easily enable scientists and astronauts to access the Moon and equip themselves with the necessary tools to create a sustainable lunar presence.
The systems under development are namely the Orion spacecraft – a newly designed crew module capable of carrying astronauts into deep-space and returning them to Earth – and the Space Launch Systems (SLS) rocket as seen in Figure 2 – a rocket notable for its unprecedented power and capable of sending the Orion capsule, astronauts and large cargo together in a single trip. As these systems will carry astronauts farther into space than ever before, they have been designed to withstand the intensity of extended spaceflight and the increased speeds and temperatures that pose a danger to deep-space travel.
Kathy Leuders, the head of NASA’s Human Exploration and Operations Mission Directorate and first woman to hold this position, has stated she is confident that the new exploration systems are the “only rocket and spacecraft capable of meeting [NASA’s] aggressive goal” to again put humans on the Moon. The Orion spacecraft has already been constructed – with the service module built and delivered by the European Space Agency (ESA) and its partner Airbus – and has already undergone preliminary testing in 2014, though not yet with humans. The SLS rocket however – built by NASA’s partner Boeing – is still undergoing final construction and testing but remains on schedule for the first Artemis mission.
Figure 2: Computer rendering of NASA’s Space Launch Systems (SLS) rocket in flight. Photo Credit: NASA Spaceflight
Artemis I is set to launch in 2021 and will serve as the first integrated test of the Orion spacecraft and the SLS rocket. Both systems will be launched from Kennedy Space Center in Florida to test the hardware and software systems of both crafts and NASA ground control. The spacecraft, however, will not have a crew. By travelling further than any crewed ship in history, the systems of Artemis I will be pushed to their extremes. The Orion spacecraft will stay in space longer than any crewed vessel, will not dock with another ship or space station, and will return to Earth faster and hotter than any craft before. The mission is calculated to take approximately three weeks during which the Orion capsule will have flown over 280,000 miles past and around the Moon before returning to Earth.
If Artemis I proves successful, NASA plans to move forward with Artemis II sometime in 2023. Artemis II will again test the Orion and SLS rocket systems, but this time with a four-person crew. The mission is set to follow a flightpath similar to that used in the Apollo missions known as a ‘hybrid free-return trajectory’, as detailed in Figure 3. A common concept in astrodynamics and used as a safety-net in case of a systems failure since Apollo, the trajectory would not require the spacecraft to use propulsion bursts to travel around the Moon, but instead would use the Moon’s gravitational pull. If the spacecraft were to use burns, a slowed velocity would result in the craft orbiting the Moon, and an increased velocity would result in the craft either bypassing the Moon or bypassing Earth depending on when the burn was initiated. Instead, the ‘free-return trajectory’ relies on the gravitational effects of the Moon to perform a slingshot manoeuvre that would see the spacecraft travel around the Moon thus providing it with sufficient velocity to break from the lunar orbit and be placed on an return course to Earth. This flight plan serves as the safest and most efficient option as the aim of Artemis II is to see if the Orion spacecraft is able to reach the Moon and return without attempting a lunar landing.
Figure 3: Rendering of the Artemis II trajectory from Earth’s orbit to lunar flyby and back to Earth.
Photo Credit: NASA
Artemis III will then be the mission to land humans on the Moon. Transporting the astronauts to lunar orbit using the Orion and SLS rocket, and the flightpath from Artemis II, the astronauts will then transfer to a lunar landing system that will take them down to the Moon for an exploration of the lunar surface. But with the human return to the Moon being a number of years away, NASA is still deciding what the astronauts of Artemis III will be doing once they reach the Moon. At present, the mission parameters have been suggested to entail an expansive exploration of the lunar surface to locate key resources that would be necessary to sustain long-term exploration, such as the predicted presence of water in ice located at the Lunar South Pole.
To reach this stage, NASA will need to progress swiftly and efficiently with the rest of its proposed technology. The lunar landing systems imperative for Artemis III are still undergoing designs within NASA and her commercial partners (Blue Origin, Dynetics and SpaceX) while it has been announced that the Gateway – a small space station to be placed in the lunar orbit – will no longer play a part in Artemis III as was previously thought.
Originally, astronauts of the Artemis III mission were reportedly set to dock with the Gateway orbital lunar station before transferring to a lunar lander and descending to the lunar surface. Dan Hartman – the program director for Gateway – mentioned that this will no longer be the case despite Gateway being operational by 2024. By not using Gateway, the Artemis III mission “will have a much higher probability of success” allowing for NASA to concentrate solely on landing humans on the Moon again without dividing its concentration to the performance of a new space station as well. In a meeting with a NASA advisory council, Hartman mentioned that NASA does not need to try to accomplish everything at once.
“For a future mission, after we demonstrate that we can get to the Moon and get a lander to work, we can then have them both dock at the Gateway.”
Figure 4: An artist’s rendering of the Gateway orbital lunar station. Photo credit: NASA
If all goes according to plan, NASA will fundamentally change the future of space travel with the Artemis program. It will set the bedrock for future off-world exploration by providing scientists and astronauts alike, the practical experience of living and operating on a foreign celestial body. The Gateway orbital lunar station – built by NASA with planned additions from international space agencies (ESA, CSA, Roscosmos & JAXA) – alongside the Orion spacecraft, SLS rocket and future lunar landers will permit humans continuous and sustainable access to the Moon and its surroundings.
While these exploration systems will all be operational by 2024, NASA has announced an additional six missions to the Artemis program. This would bring the total to nine Artemis missions during which NASA intends to create permanent infrastructure on the lunar surface and further expand the Gateway orbital station. In doing so, humans will be able to explore areas of the Moon that have never been accessed. Humans will also be able to research and uncover the mysteries of the lunar surface, and by extension perhaps learn more about planet Earth. Through such exploration, NASA will be opening our world up to a new era of deep-space travel and interstellar colonization.
– Evan Cook
About the Author:
Evan works as a content writer for UK Analogue Mission. He has a Master’s Degree in creative writing from the University of Surrey and is an award-winning short-story writer and playwright.