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Apollo 17 – Glorious history in moon exploration

The Apollo 17 mission, a remarkable chapter in the annals of space exploration, marked the culmination of NASA’s Apollo program. This mission, while signifying the end of an era of manned lunar exploration, left a lasting legacy of scientific discovery and technological achievement.

Overview of the Apollo 17 Mission

Apollo 17 was launched on December 7, 1972, embarking on a journey that would represent the final crewed mission to the Moon in the 20th century. Commanded by veteran astronaut Eugene Cernan, Apollo 17 was unique in its crew composition and mission objectives. Cernan, a seasoned astronaut who had previously flown on Gemini 9A and Apollo 10, was joined by Ronald Evans, the command module pilot, and Harrison “Jack” Schmitt, a geologist and the first scientist-astronaut to participate in a NASA mission.

This mission was distinguished by several firsts and records. Notably, Apollo 17 was the first mission to adopt a “direct ascent” trajectory, utilizing the powerful Saturn V rocket to launch directly to the Moon without entering Earth orbit. This approach streamlined the journey, making the mission more efficient.

Another significant innovation was the inclusion of the Lunar Roving Vehicle (LRV), a lightweight electric car that enabled Cernan and Schmitt to traverse the lunar surface far beyond their landing site. This mobility allowed them to conduct more extensive geological surveys and collect a wider array of lunar samples than their predecessors.

During their stay, Cernan and Schmitt conducted three extravehicular activities (EVAs), spending a total of over 22 hours exploring the lunar surface. Meanwhile, Evans orbited the Moon in the Command Module, conducting vital scientific experiments.

Historical Context of NASA’s Apollo Program

The Apollo 17 mission must be understood in the broader context of NASA’s Apollo program. Initiated in the early 1960s, the Apollo program was a response to President John F. Kennedy’s ambitious call to land a man on the Moon and return him safely to Earth before the decade’s end. This program was not only a demonstration of technological prowess and human courage but also a key element of the Cold War space race between the United States and the Soviet Union.

Over the course of the program, NASA achieved unprecedented milestones in space exploration. This included the first successful manned lunar landing by Apollo 11 in 1969 and subsequent missions that expanded our understanding of the Moon. Each mission contributed valuable insights into lunar geology, the feasibility of sustained human presence in space, and the challenges of extraterrestrial travel.

Apollo 17, as the final mission of this groundbreaking program, represents both an end and a lasting legacy. It showcased the zenith of lunar exploration capabilities of its time and laid the foundation for future endeavors in space exploration, science, and technology.

Mission Preparation and Crew

The success of the Apollo 17 mission was anchored in meticulous preparation and the unique composition of its crew. Each member brought a distinct set of skills and experience, contributing significantly to the mission’s achievements.

Crew Profile: Eugene Cernan, Ronald Evans, and Harrison Schmitt

• Eugene Cernan: Serving as the mission commander, Eugene Cernan was a seasoned astronaut with significant spaceflight experience. Prior to Apollo 17, Cernan had participated in the Gemini 9A mission and the Apollo 10 mission, the latter being a “dress rehearsal” for the first Moon landing. His expertise in spaceflight operations and his leadership qualities were crucial for the success of Apollo 17.
• Ronald Evans: As the command module pilot, Ronald Evans was responsible for piloting the command module, named “America,” which orbited the Moon while his crewmates explored the lunar surface. Evans played a pivotal role in orbital science activities, including capturing photographic data and conducting experiments.
• Harrison “Jack” Schmitt: A geologist by training, Schmitt was the first scientist-astronaut to participate in a NASA mission. His inclusion marked a significant shift toward integrating scientific expertise directly into lunar exploration. Schmitt’s knowledge of geology enabled the team to conduct more sophisticated analyses of lunar materials and surface features.

Training and Mission Objectives

The crew underwent extensive training in preparation for their lunar expedition. This included geological field training to prepare Schmitt and Cernan for lunar surface activities, simulations of lunar module operations, and practice in using the Lunar Roving Vehicle. Additionally, all three astronauts received training in scientific experimentation and emergency procedures.

The mission objectives of Apollo 17 were comprehensive, blending exploration, scientific research, and technological demonstrations:

• Geological Survey and Sample Collection: A primary objective was to collect a diverse array of lunar samples to better understand the Moon’s geological history. Schmitt’s expertise was instrumental in identifying significant rock and soil samples.
• Surface Experiments: The crew set up and conducted experiments on the lunar surface, including seismic studies and heat flow measurements, to gather data about the Moon’s interior and surface environment.
• Technological Demonstrations: Apollo 17 tested key technologies, including the Lunar Roving Vehicle, which expanded the astronauts’ range on the Moon, and the Lunar Module’s capabilities in a direct ascent trajectory.
• Orbital Science: While Schmitt and Cernan explored the lunar surface, Evans conducted important experiments in lunar orbit, studying the Moon’s atmosphere and magnetic field.

The preparation and training undertaken by the Apollo 17 crew were critical in meeting these objectives, culminating in a mission that not only advanced lunar exploration but also expanded our understanding of the Moon and space travel.

Launch and Journey to the Moon

The Apollo 17 mission’s journey to the Moon was a testament to human engineering and space travel capabilities at the time. The mission’s success was anchored on the robust performance of the Saturn V rocket and the efficient trajectory it followed.

The Saturn V Rocket and Direct Ascent Trajectory

The Saturn V rocket, renowned for being one of the most powerful rockets ever built, was integral to the Apollo 17 mission. Standing taller than a 36-story building and weighing more than 6 million pounds, it was designed to carry humans beyond low Earth orbit.

For Apollo 17, a significant change was made in the mission trajectory. Unlike previous Apollo missions that used a multi-stage approach involving Earth orbit before heading to the Moon, Apollo 17 employed a “direct ascent” trajectory. This route involved launching directly from Earth to the Moon, eliminating the need for an initial Earth orbit phase. This approach reduced the mission’s complexity and allowed for a more straightforward path to the Moon.

The Saturn V rocket’s third stage provided the necessary thrust to escape Earth’s gravity and set the spacecraft on a course for the Moon, a journey that would take approximately three days.

Key Milestones During the Moonward Journey

Several key milestones marked Apollo 17’s journey to the Moon:

• Trans-Lunar Injection (TLI): After reaching a designated altitude and velocity, the Saturn V’s third stage reignited to perform the TLI, placing the spacecraft on its path to the Moon.
• Course Corrections: During the journey, minor course corrections were made to ensure accurate trajectory and timing for lunar orbit insertion.
• Crew Activities: The journey to the Moon allowed the astronauts to prepare for lunar operations. This included checking equipment, conducting experiments, and preparing for lunar landing.
• Lunar Orbit Insertion: As the spacecraft neared the Moon, the Service Module engine ignited to slow the spacecraft down, allowing it to be captured by the Moon’s gravity and enter lunar orbit.
• Lunar Module Checkout: Prior to landing, Cernan and Schmitt entered the Lunar Module (LM) to check systems and prepare for descent to the lunar surface.

This carefully orchestrated journey to the Moon, powered by the Saturn V and navigated by skilled astronauts and mission control, was a critical phase of the Apollo 17 mission. It set the stage for the historic lunar surface exploration that would follow, highlighting the capabilities of both the technology and the individuals involved in this extraordinary endeavor.

Lunar Module and Lunar Roving Vehicle

The Apollo 17 mission was distinguished by its use of advanced lunar exploration technologies, most notably the Lunar Module (LM) and the Lunar Roving Vehicle (LRV). These technologies played a critical role in the mission’s exploration activities on the Moon.

Design and Capabilities of the Lunar Module (LM)

The Lunar Module, named “Challenger” for the Apollo 17 mission, was a two-stage vehicle designed specifically for lunar surface operations. Its design was a marvel of engineering, tailored to operate in the Moon’s vacuum and low-gravity environment.

• Structure: The LM consisted of two primary sections: the descent stage and the ascent stage. The descent stage contained the landing gear, engines, and fuel required for landing on the Moon, as well as scientific equipment and the Lunar Roving Vehicle. The ascent stage housed the crew cabin, life support, and control systems for the return to lunar orbit.
• Capabilities: The LM was equipped with a descent engine that allowed for a controlled landing on the lunar surface. Once the surface mission was completed, the ascent stage engine would transport the astronauts back to the Command Module in lunar orbit. The LM’s design also included advanced navigation and communication systems, necessary for the precise operations on the Moon.
• Performance: The LM for Apollo 17 was designed with improvements over previous modules, reflecting the increased duration and complexity of the mission. It allowed for longer stays on the lunar surface and carried more scientific equipment.

Introduction and Use of the Lunar Roving Vehicle (LRV)

The Lunar Roving Vehicle was a key addition to the Apollo 17 mission, enhancing the scope and range of lunar exploration.

• Design: The LRV was a lightweight, electric-powered vehicle designed to travel over the lunar terrain. It was foldable and compact, allowing it to be stored in the Lunar Module’s descent stage. Equipped with four wheels, a basic navigation system, and a communications setup, the LRV was built to carry two astronauts, their equipment, and lunar samples.
• Usage: The LRV allowed astronauts Cernan and Schmitt to travel much farther from the LM than was possible on foot, expanding the range of exploration and sample collection. It enabled them to visit geological features of interest, conduct experiments at multiple sites, and transport a greater volume of lunar samples.
• Significance: The introduction of the LRV represented a significant advancement in lunar surface exploration. It provided a means to conduct more extensive and diverse scientific investigations, contributing greatly to the overall success of the mission.

The Lunar Module and Lunar Roving Vehicle were instrumental in Apollo 17’s achievements. They exemplify the ingenuity and effectiveness of engineering solutions specifically designed for space exploration, showcasing humanity’s ability to extend its reach beyond Earth.

Lunar Surface Exploration

The Apollo 17 mission marked a significant milestone in lunar exploration, with astronauts Eugene Cernan and Harrison Schmitt conducting extensive research and exploration on the Moon’s surface. The mission’s success in this area was marked by a series of well-planned and executed activities.

Landing in the Taurus-Littrow Valley

Apollo 17’s Lunar Module, Challenger, made a successful landing in the Taurus-Littrow Valley, a site selected for its geological diversity and potential for significant scientific discoveries. This area is located on the southeastern edge of the Sea of Serenity and is characterized by its unique highland and mare geology, offering a rich field for scientific study.

• Site Selection: The Taurus-Littrow Valley was chosen for its varied landscape, which included large boulders, steep slopes, and craters. This diversity promised a rich collection of geological samples and data.
• Landing Challenges: The landing required precise maneuvering due to the valley’s rugged terrain. The success of this landing was a testament to the skill of the astronauts and the reliability of the Lunar Module.

Extravehicular Activities (EVAs) and Moonwalks

The mission included three Extravehicular Activities (EVAs), commonly known as moonwalks, which totaled over 22 hours. These EVAs were integral to the mission’s scientific and exploratory goals.

• EVA Objectives: During these EVAs, Cernan and Schmitt conducted a variety of tasks including setting up scientific experiments, exploring the lunar terrain, and collecting geological samples.
• Traverse and Exploration: Utilizing the Lunar Roving Vehicle, the astronauts were able to cover significant ground, visiting key geological sites and conducting in-depth analyses of the lunar surface.
• Record-Breaking Activity: The first EVA was the longest in duration, lasting over 7 hours, and set a record for the longest moonwalk.

Geological Exploration and Sample Collection

The geological exploration and sample collection conducted by Cernan and Schmitt were central to the mission’s scientific success.

• Diverse Samples: The astronauts collected over 110 kg (243 lbs) of lunar materials, including rocks and soil. These samples were key to understanding the Moon’s geological history.
• Scientific Contribution: Schmitt, being a trained geologist, played a crucial role in identifying and explaining the geological features encountered. This included the discovery of the famous “orange soil,” indicative of volcanic activity.
• The “Trophy Rock”: Among the samples collected was a special rock, later known as the “Trophy Rock,” which was presented to President Richard Nixon. This rock symbolized the mission’s scientific and exploratory achievements.

The lunar surface exploration conducted during the Apollo 17 mission significantly advanced our understanding of the Moon. The findings from the EVAs, the geological explorations, and the samples collected have continued to provide invaluable insights into lunar science and the history of the solar system.

Scientific Experiments and Findings

The Apollo 17 mission contributed significantly to lunar science through a series of meticulously planned geological experiments and analyses. The findings from these experiments have deepened our understanding of the Moon’s history and composition.

Geologic Sampling and Analysis

A primary objective of Apollo 17 was the collection and analysis of lunar geological samples. This task was undertaken with a focus on obtaining a diverse range of specimens that could provide insights into the Moon’s geologic history.

• Sampling Techniques: The astronauts employed various tools and methods to collect soil samples, core tubes, and rock samples. The use of the Lunar Roving Vehicle allowed them to reach multiple geological formations, enhancing the diversity of the collected samples.
• Analytical Results: The samples underwent detailed analysis both on-site and post-mission. These analyses provided insights into the Moon’s volcanic activity, the presence of impact-generated materials, and the processes of soil formation on the lunar surface.
• Scientific Impact: The data gathered from these samples has been instrumental in shaping current theories about the Moon’s formation and evolution, including insights into the early solar system.

The “Trophy Rock” and Its Significance

One of the most notable samples collected during Apollo 17 was a large, rounded boulder dubbed the “Trophy Rock”. This sample held particular significance for several reasons:

• Unique Composition: The rock was a breccia, composed of fragments of different types of rocks fused together, indicating a history of significant impact events.
• Symbolic Value: The Trophy Rock symbolized the scientific achievements of not just Apollo 17, but of the entire Apollo program. It represented the culmination of a series of missions dedicated to exploring and understanding the Moon.
• Legacy: The rock was presented to President Richard Nixon as a symbol of the scientific and exploratory success of the Apollo missions.

Contributions of Harrison Schmitt as a Scientist-Astronaut

Harrison Schmitt, as the first scientist-astronaut to participate in a lunar landing, played a pivotal role in the Apollo 17 mission:

• Expert Analysis: Schmitt’s expertise as a geologist allowed for more informed observations and analyses of the lunar surface. His ability to identify and describe geological features in real-time added significant depth to the mission’s scientific findings.
• Educational Impact: Schmitt’s presence on the mission highlighted the importance of incorporating scientific expertise directly into space exploration. His contributions demonstrated the value of having specialized knowledge to guide exploratory activities.
• Advancing Lunar Science: Schmitt’s work on Apollo 17 provided a model for future missions, showcasing how scientific expertise can be integrated into space exploration to maximize scientific returns.

The scientific experiments and findings of the Apollo 17 mission, bolstered by the unique contributions of a scientist-astronaut, have left an indelible mark on our understanding of lunar science and the broader field of planetary geology.

Engineering Experiments and Achievements

The Apollo 17 mission was not only a scientific triumph but also a showcase of remarkable engineering experiments and achievements. These technical accomplishments played a crucial role in the mission’s success and contributed to the advancement of space exploration technology.

Studies of the LM’s Descent Engine

One of the key engineering aspects of the Apollo 17 mission involved the Lunar Module’s (LM) descent engine. The LM’s descent stage was equipped with a throttleable engine, a critical component for ensuring a controlled and safe landing on the lunar surface.

• Engine Performance: The descent engine was meticulously tested to evaluate its performance in varying conditions. This included assessing its throttle response, fuel efficiency, and stability during the descent phase.
• Improvements and Reliability: The engine on Apollo 17’s LM incorporated improvements based on experiences from previous missions. Its reliability was a testament to the advancements in space propulsion technology developed during the Apollo program.

Performance Testing of the LRV

The Lunar Roving Vehicle (LRV), used for the first time in an Apollo mission, underwent extensive performance testing:

• Maneuverability and Range: The LRV was tested for its ability to traverse the lunar terrain. Its performance in terms of maneuverability, range, and ability to carry equipment and lunar samples was crucial for the mission’s exploratory goals.
• Technical Assessment: The LRV’s electric drive system, suspension, and navigation equipment were scrutinized under actual lunar conditions. This provided valuable data for future designs of lunar and planetary rovers.

Record-Setting Achievements of the Apollo 17 Mission

Apollo 17 set several records, underscoring its significance in the annals of space exploration:

• Longest Lunar Stay: The mission achieved the longest crewed lunar stay – nearly 75 hours on the Moon’s surface. This extended period allowed for a comprehensive exploration and study of the lunar environment.
• Extended EVA Duration: The mission’s first EVA lasted 7 hours and 15 minutes, setting a record for the longest single moonwalk.
• First Night Launch and Landing: Apollo 17 was notable for being the first crewed space mission to have a night launch and subsequent night landing, marking a significant achievement in spaceflight operations.

These engineering experiments and achievements not only marked Apollo 17 as a milestone mission but also contributed valuable knowledge and experience that would inform future space exploration endeavors. The mission’s technical successes paved the way for advancements in spacecraft design, lunar exploration techniques, and rover technology.

Return to Earth and Mission Conclusion

The Apollo 17 mission, after accomplishing its objectives on the lunar surface, embarked on the journey back to Earth, concluding one of the most significant chapters in the history of space exploration.

Departure from the Moon and Lunar Orbits

After their extensive exploration of the Taurus-Littrow Valley, astronauts Cernan and Schmitt returned to the Lunar Module and prepared for liftoff from the Moon.

• Lunar Module Ascent: The ascent stage of the Lunar Module, carrying the astronauts and the lunar samples, successfully lifted off from the Moon’s surface. This marked the last time humans left the lunar surface.
• Rendezvous and Docking: In lunar orbit, the ascent stage rendezvoused and docked with the Command Module, piloted by Ronald Evans. The lunar samples and astronauts were transferred to the Command Module.
• Final Lunar Orbits: Before heading back to Earth, the Command Module completed additional orbits of the Moon. These orbits allowed for further scientific observations and data collection.

Re-entry and Splashdown in the Pacific Ocean

The return journey to Earth was a critical phase of the mission, requiring precise maneuvers and careful navigation.

• Trans-Earth Injection: The spacecraft’s Service Module engine was fired for Trans-Earth Injection, setting Apollo 17 on its course back to Earth.
• Re-entry: The spacecraft re-entered Earth’s atmosphere, a process that involved withstanding extreme heat due to friction with the atmospheric gases.
• Splashdown: Apollo 17 successfully splashed down in the Pacific Ocean on December 19, 1972. The precision of the splashdown was a testament to the accuracy of the mission’s planning and execution.

Impact and Legacy of Apollo 17

Apollo 17’s return marked the end of the Apollo lunar missions, but its legacy continues to influence space exploration.

• Scientific Contributions: The mission contributed a wealth of scientific data and lunar samples, which have been critical in advancing our understanding of the Moon and solar system history.
• Technological Advancements: The engineering feats achieved during Apollo 17, including the use of the Lunar Roving Vehicle and the extended stay on the lunar surface, set new standards for future space missions.
• Inspirational Legacy: Apollo 17, as the last crewed mission to the Moon of the 20th century, left a lasting legacy that continues to inspire new generations of explorers and scientists. The mission symbolized the pinnacle of human exploration and set the stage for future endeavors in space.

The successful return of Apollo 17 and its crew marked the conclusion of an era of extraordinary human and technological achievement in space exploration. The mission’s impact extends far beyond its scientific and technological accomplishments, serving as a beacon of human curiosity, ingenuity, and the relentless pursuit of knowledge.

Reflections and Future Directions

The Apollo 17 mission, while marking the end of NASA’s Apollo lunar program, has left an enduring legacy in the annals of space exploration. Its accomplishments and lessons continue to shape current and future space missions.

Apollo 17’s Place in Space Exploration History

Apollo 17 holds a unique and revered place in space exploration history. It represents the culmination of an era of unprecedented exploration and achievement in human spaceflight.

• Pinnacle of Apollo Program: Apollo 17 is often remembered as the pinnacle of the Apollo program, showcasing the most extended lunar surface exploration and the greatest amount of lunar material returned to Earth.
• Integration of Science and Exploration: The mission is particularly noted for integrating scientific inquiry with exploration, especially with the inclusion of Harrison Schmitt, a scientist-astronaut, on its crew. This set a precedent for future missions to include professional scientists in their crews.
• Public Engagement: Apollo 17, like its predecessors, captured the imagination of people around the world, fostering a widespread interest in space and science. The iconic images and words from this mission have become a part of the collective memory of humanity’s journey into space.

Lessons Learned and Implications for Future Missions

The experiences and knowledge gained from Apollo 17 have provided valuable lessons for future space missions.

• Technological Innovations: The advancements in spacecraft design, lunar roving, and surface activities have informed the development of new technologies for subsequent space programs. These innovations lay the groundwork for more complex missions, including those planned for Mars and other celestial bodies.
• Scientific Exploration: The mission underscored the importance of direct scientific exploration of extraterrestrial bodies. The extensive geological work done on the Moon has been instrumental in shaping our understanding of planetary processes.
• Sustainability and Longevity: Apollo 17 showed the feasibility of longer-duration stays on extraterrestrial surfaces, paving the way for future missions that aim to establish a more sustained human presence in space.
• International Collaboration: The mission highlighted the value of global cooperation in space exploration. The scientific data and samples collected during Apollo 17 have been shared internationally, fostering collaboration and contributing to a global understanding of lunar science.

In reflection, Apollo 17 not only marked the end of an era but also set the stage for the future of space exploration. The mission’s achievements and the lessons it imparted continue to inspire and inform contemporary and future space endeavors, driving humanity’s unending quest to explore and understand the universe.

Appendices for Apollo 17

The appendices provide detailed information on the Apollo 17 mission, including a timeline of key events, a list of samples collected, and technical specifications of the equipment used.

Detailed Mission Timeline

• December 7, 1972: Launch of Apollo 17 at 12:33 AM EST from Kennedy Space Center.
• December 11, 1972: Lunar Module ‘Challenger’ lands in the Taurus-Littrow Valley on the Moon.
• December 11-14, 1972: Three EVAs (Extravehicular Activities) are conducted, totaling 22 hours and 4 minutes on the lunar surface.
• December 14, 1972: Lunar Module ascent stage lifts off from the Moon.
• December 17, 1972: Command Module ‘America’ leaves lunar orbit.
• December 19, 1972: Splashdown in the Pacific Ocean at 2:25 PM EST.

List of Samples Collected

Apollo 17 astronauts collected a total of 110 kg (243 lbs) of lunar material, including:

• Soil Samples: Various soil samples from different locations within the Taurus-Littrow Valley.
• Rock Samples: A diverse range of rock samples, including basalts, breccias, and the unique “orange soil.”
• Core Samples: Several deep core samples providing insights into the subsurface lunar geology.
• Special Sample: The “Trophy Rock” (sample no. 70017), a large breccia collected as a symbol of the Apollo missions.

Technical Specifications of Apollo 17 Equipment

• Saturn V Rocket:
  • Height: 363 feet (111 meters)
  • Mass: 6.2 million pounds (2.8 million kilograms)
  • Payload to LEO: 310,000 pounds (140,000 kilograms)
• Command/Service Module ‘America’:
  • Diameter: 12.8 feet (3.9 meters)
  • Height (with docking adapter): 36.2 feet (11.04 meters)
  • Mass: 32,390 pounds (14,696 kilograms)
• Lunar Module ‘Challenger’:
  • Height: 23 feet (7 meters)
  • Mass (ascent and descent stages): 36,000 pounds (16,400 kilograms)
  • Crew Capacity: 2 astronauts
• Lunar Roving Vehicle (LRV):
  • Weight: 463 pounds (210 kilograms)
  • Speed: Up to 8 miles per hour (13 kilometers per hour)
  • Range: 57 miles (92 kilometers)

Apollo 17: Links and further sources

Academic Journals and Research Papers

1. Journal of Geophysical Research: Planets: Look for articles detailing lunar geology and the Apollo missions.
2. NASA Technical Reports Server (NTRS): Search for Apollo 17 mission reports at ntrs.nasa.gov.

Books

1. “Apollo 17: The NASA Mission Reports” by Robert Godwin: A compilation of NASA mission reports that provide detailed accounts of the mission.
2. “Last Man on the Moon” by Eugene Cernan: This autobiography of Eugene Cernan, Apollo 17 commander, offers a personal perspective on the mission.

Online Resources

1. NASA’s Official Website: Visit www.nasa.gov for comprehensive information on the Apollo 17 mission.
2. Lunar and Planetary Institute: The website www.lpi.usra.edu provides extensive resources on lunar science, including the Apollo missions.
3. The Apollo Lunar Surface Journal: An excellent online resource for detailed mission transcripts and commentary at www.hq.nasa.gov/alsj/.

Multimedia Archives

1. NASA Image and Video Library: Search for Apollo 17 images and videos at images.nasa.gov.
2. YouTube: Channels like NASA’s official channel or space-related documentary channels often feature content on Apollo missions.

Libraries and Archives

1. National Air and Space Museum: Their archives contain extensive material on the Apollo program.
2. Local University Libraries: Many university libraries have collections related to space exploration, particularly those with aerospace programs.