50 years after the final Apollo landing, we started another era of lunar exploration
Author: Danny Tjokrosetio, James Perry, Leonardo Times Editors
“As we leave the Moon at Taurus-Littrow, we leave as we came, and, God willing, we shall return, with peace and hope for all mankind.” Gene Cernan, commander of Apollo 17, spoke the last words on the Moon 50 years ago [1]. We are returning – this time to stay.
Tension and excitement built around the Kennedy Space Center as hundreds of thousands of people gathered to watch a momentous rocket launch. Plumes beneath a skyscraper-sized structure ignited the night sky. The colossus rose above the ground, trailed by blazes so bright, it appeared as if a celestial being tore up the heavens. Shortly after, delayed sonic booms deafened the noise of the cheering crowd. A rocket was on its way to the Moon.
The scene described above can be used to verbally paint two separate events taking place five decades apart – but they are not exact parallels in history. The launch of Apollo 17 on December 7, 1972, marked the flight of the last lunar Saturn V, a closing chapter in the Apollo era. The Artemis era recently kicked off with the launch of the first SLS vehicle on November 16, 2022, taking Artemis 1 to lunar orbit and back.
The Artemis program, NASA’s return to the Moon, is often referred to as the Apollo of our generation. Artemis, however, will be more than just flags and footprints or short geological excursions. We are going back to the Moon to settle there. However, there clearly are some parallels and lessons learned from our first efforts to land humankind on the Moon.
LOST LUSTER
There were initially three more missions to follow Apollo 17. However, a lack of political and public interest resulted in the cancellation of Apollos 18 to 20. 650 million people had their eyes glued onto their TV sets when Neil Armstrong took his one small step on the lunar surface in 1969. But Apollo missions to the Moon eventually became routine and mundane for the general public. So much so that CBS received a bushel of complaints and concerns when they chose to broadcast the launch of Apollo 17 instead of the drama series Medical Center, which was part of their standard program [2]. After the United States achieved the goal of landing man on the Moon before 1970 and defeated the Soviets, interest in moon flights dwindled.
NOT-SO-IDENTICAL TWINS
Artemis is said to be the Apollo of our generation, but the two programs do not share many similarities besides a common destination. For starters, Apollo was developed out of political incentives at the height of the Cold War; a rush to one-up the Soviets and their seemingly endless space feats. Kennedy, not wanting his beloved nation to run behind the enemy, proposed a bold vision to land a man on the Moon and recover him safely before the end of the decade. Despite the first generation of Moon landings being set up to display technological prowess against an opposing ideology, valuable science was conducted. Our current knowledge of lunar geology, composition, and formation, as well as lunar clues leading up to the understanding of our solar system and life on Earth, is a legacy of Apollo.
Apollo was a series of mere camping trips to our nearest neighbor. Disregarding the “flags and footprints” approach, Artemis aims to set up a long-term and sustainable human presence on lunar soil and its vicinity. Its purpose can be summed up in two words: science and exploration. Besides thorough scientific investigations, Artemis aims to use the Moon as a stepping stone to Mars by setting up lunar bases and maturing the technologies necessary to get us beyond the Moon [3]. Despite their differences, Artemis builds on the lessons learned from Apollo.
THE AIMS OF ARTEMIS III
The third mission of the Artemis program will descend the “first woman and the next man” to the lunar south pole, the first humans on the Moon since Apollo 17, in 2024 [4]. Despite a wealth of data from the Apollo missions, which includes recovered sample analysis, robotic explorers and computer modeling brought about new insight and curiosity during the semicentennial gap in crewed lunar exploration. Based on the new questions resulting from these studies, as well as countless suggestions from white papers and the Planetary Science Decadal Survey, NASA’s Science Mission Directorate (SMD) prepared a proposal for the science goals to be conducted by Artemis 3. These goals are divided into seven objectives [5]:
- Understanding planetary processes
- Understanding the character and origin of lunar polar volatiles
- Interpreting the impact history of the Earth-Moon system
- Revealing the record of the ancient sun and our astronomical environment
- Observing the universe and the local space environment from a unique location
- Conducting experimental science in the lunar environment
- Investigating and mitigating exploration risks
15 findings and recommendations were made following these objectives, the first of which emphasizes an “optimal sample-return program…made by well-trained astronauts”, with the recommendation that “astronauts should participate in an Apollo-style course in geology and planetary science, including both field and classroom components”. To the Apollo astronauts, who were test pilots by background, conducting geological investigations was as foreign as performing plastic surgery. There was, of course, an exception: Apollo 17’s lunar module pilot, geologist Harrison “Jack” Schmitt, was the first scientist-astronaut. Trained by the crème de la crème of global geologists, the intense crash courses on geology undergone by the Apollo astronauts gave them the equivalent of a Master’s degree in the field [6]. Geological field trips were made both nationally and internationally and took place in Arizona, Texas, Nevada, Hawaii, and Iceland.
In order to lay the foundations for permanent operations on the lunar surface, NASA aims for the experiment packages left behind by Artemis astronauts to be powered long-term and have the capability to communicate with each other in a network. Some analysis is only possible using equipment on Earth. In 2020, The Lunar Exploration Analysis Group (LEAG) recommended to NASA that the samples brought back from the Moon exceed 150kg [7]. NASA has also recommended itself to develop cryogenic storage of samples, to preserve volatile properties during the ten-day journey home [5].
Since Apollo 12, Apollo Lunar Surface Experiments Packages (ALSEP) were deployed on the lunar surface, providing geophysical and environmental monitoring until the end of the program in 1977. In contrast to the Apollo missions, which all landed near the equator on the nearside of the Moon, the near-rectilinear halo orbit of the gateway space station will allow for polar landing sites. These are of special interest for sample collection, as it may be possible to obtain samples from both the geologically distinct near and far sides of the Moon [5].
THE PROBLEM WITH DUST
Lunar regolith covers the surface at a depth between 5m and 10m, yet dust electrostatically charged by the sun also floats, suspended above it [8]. This same charge caused it to stick to surfaces such as the Lunar Roving Vehicle (LRV) radiators, incorrectly designed with the assumption that this dust could be simply brushed off, as samples returned from previous missions could be on Earth. There is also ground to believe that breathing in this dust could have toxic effects, damaging the lungs and potentially causing cancer to develop over time. On the Apollo 16 mission, so much dust was brought back into the Lunar Module that the astronauts remained in their spacesuits until redocked with the Command Module, which they only entered after having vacuum-cleaned the majority of the dust off themselves [9]. Time spent cleaning up dust is valuable time not spent performing science, hence Artemis III will further investigate the properties of lunar dust, especially at the poles where its behavior is not yet known [5].
From Artemis IV onwards, an unpressurized rover named the Lunar Terrain Vehicle (LTV) is planned to be pre-positioned on the moon’s surface. However, as the program continues with the ultimate goal of establishing a ‘Base Camp’ on the Moon, astronauts will eventually use a pressurized rover to get around, allowing them to travel and live far away from any lunar lander or surface habitat for short periods of time. NASA envisions such a vehicle for the first manned mission to Mars. This is just one of the many hoped technologies the Artemis missions will realize [5]. By contrast, the relatively simplistic LRV was carried on Apollos 15 through 17, reaching a maximum range of 7.6km from the Lunar Module on the last of those missions. The rover was simply attached to the outside of the lander and deployed by the astronauts using a pulley system [10].
THE NEXT SMALL STEP
In the Artemis III mission, NASA plans for the SLS rocket to launch four crew members in the Orion Capsule to a space station already placed in orbit of the Moon named the Lunar Gateway. From there, astronauts can transfer to a separately launched lunar lander, transporting them to and from the surface [3]. Although the subcontract of the lunar lander was similar – the strategy of the Apollo program was quite different, each mission being achieved entirely through one launch. Grumman Aerospace Corporation later merged into Northrop Grumman, was awarded a contract to provide this lander by NASA in 1962. However, its development suffered delays and first flew on an unmanned Saturn IB six years later, a year later than planned. Similarly, the first crewed flight was delayed last minute from Apollo 8 to 9, again by another year [11].
Whether SpaceX, the current contract holder for the new lander following a similar selection process, will encounter similar delays is yet to be seen. The company must overcome the unique challenge in that the launch vehicle required, the Super Heavy Booster, is also yet to be flown, just three years before the planned Artemis III mission. While Artemis IV hopes to use the same craft, the modularity of the Artemis program has allowed NASA to issue a call for design proposals for future missions from different companies [12], encouraging commercial competition. Following the devastating fire on the launch pad of Apollo 1, which tragically killed Astronauts Virgil Grissom, Edward White and Roger Chaffee, the following Apollos 4-6 launched as uncrewed test flights [11]. Artemis I conducts a similar unmanned flight, with the crewed lunar orbit of Artemis II reminiscent of Apollo 10, a dress rehearsal for the first landing attempt.
CONCLUSION
Human lunar exploration was, frankly, born out of fierce competition – but has turned into a global cooperative effort today, reflected by Orion’s European Service Module and the Artemis Accords. Much has evolved, with the reason for going to the Moon being a major part of the change. Artemis and Apollo are indeed strikingly different; the echoes of Apollo, however, are still audible in Artemis. Artemis continues to carry the fire first blazed by Apollo.
REFERENCES
[1]: Dunbar, B. (2021, July 20). July 20, 1969: One Giant Leap For Mankind. NASA. https://www.nasa.gov
[2]: Connor, John B. (1972, December 14). Apollo 17 Coverage Gets Little Viewer Response. New York Times.
[3]: Dunbar, B. (n.d.). NASA: Artemis. NASA. Retrieved November 22, 2022, from https://www.nasa.gov
[4]: Potter, S. (2021, January 4). NASA Publishes Artemis Plan to Land First Woman, Next Man on Moon. NASA. Retrieved November 23, 2022, from https://www.nasa.gov
[5]: NASA. (2020). Artemis III Science Definition Team Report. NASA.
[6]: Kortsha, M. (n.d.-b). From Earth to the Moon. University of Texas at Austin. Retrieved November, 23, 2022, from https://www.jsg.utexas.edu
[7]: LEAG 2020 Annual Meeting Findings. (n.d.). Retrieved November 26, 2022, from https://www.hou.usra.edu
[8]: Gianonne, M. (2021, June 10). Dust: An Out-of-This World Problem. NASA. https://www.nasa.gov
[9]: Creel, R. (n.d.). Apollo Dust Lessons Learned For Artemis [Slide show]. https://www3.nd.edu
[10]: Williams, D. R. (2016, May 19). The Apollo Lunar Roving Vehicle. NASA Space Science Data Coordinated Archive. https://nssdc.gsfc.nasa.gov
[11]: Brooks, C. G., Grimwood, J. M., & Swenson, L. S. (1979). Chariots for Apollo: A History of Manned Lunar Spacecraft. https://www.hq.nasa.gov
[12]: NASA. (2022, March 23). NASA Provides Update to Astronaut Moon Lander Plans Under Artemis [Press release]. https://www.nasa.gov