Packing for Mars

by Mary Roach

Troy Shu
Troy Shu
Updated at: April 28, 2024
Packing for Mars
Packing for Mars

Explore the captivating insights of "Packing for Mars" with our comprehensive book summary. Discover the unique challenges astronauts face, the role of simulations, and the profound realities of long-duration space exploration. Gain practical knowledge to apply these learnings.

What are the big ideas?

Astronauts vs. Machinery

Astronauts present unique challenges compared to mechanical parts in space missions, requiring complex accommodations due to their physiological and psychological needs.

Simulating the Cosmos

Extensive use of simulations and mock-up environments on Earth help prepare for the unpredictabilities of space, visually and tactically mimicking real space scenarios.

Human Factors in Space

Space exploration requires consideration of human psychological and physiological responses, from motion sickness to the reorientation of sensory perception in zero gravity.

Cultural Impact on Astronaut Selection

Cultural traits influence astronaut selection, with agencies like JAXA considering Japanese cultural predispositions towards teamwork and emotional restraint.

The Reality of Long-Duration Spaceflight

Long missions pose significant physical and psychological challenges, including issues from confinement and isolation to effects on bone and muscle mass.

Space Exploration's Blend of Sublime and Ridiculous

Space travel juxtaposes sublime views and profound experiences with mundane and bizarre challenges, reflecting the complex nature of human endeavors in space.

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Astronauts vs. Machinery

Astronauts pose unique challenges compared to mechanical parts in space missions. Unlike stable, undemanding machinery, astronauts have fluctuating metabolisms, puny memories, and fragile frames that come in a million configurations. They are unpredictable and inconstant, requiring extensive accommodations for their physiological and psychological needs.

Engineers must worry about the water, oxygen, and food astronauts require, as well as the extra fuel needed to launch their supplies. Astronauts also excrete, panic, and fall in love, introducing complex human factors that mechanical parts do not. Their structural elements can even start to break down without gravity. Suspending this organism evolved for Earth in the wasteland of space is a preposterous but captivating undertaking.

The human element makes space exploration endlessly intriguing, but also presents significant logistical challenges. Astronauts must be toilet-trained and dressed in flight suits, requiring an entire odd universe of mock outer space to be built on Earth. Accommodating the astronaut's physiological and psychological needs is a far more complex task than dealing with stable, predictable machinery.

Here are specific examples from the context that support the key insight that astronauts present unique challenges compared to mechanical parts in space missions, requiring complex accommodations due to their physiological and psychological needs:

  • The NASA team was uncomfortable using a human cadaver in their testing, preferring the euphemism "postmortem human subject" instead of "cadaver". This discomfort was due to the associations with past space disasters like Challenger and Columbia.

  • In the 1960s, the Apollo program conducted impact tests using live human volunteers who endured forces up to 36 G's, leading to injuries like torn heart valves and ruptured eardrums. This was seen as necessary to ensure the safety of the astronauts.

  • Early space research focused extensively on basic physiological functions like eating, drinking, and urinating in zero gravity, which presented new and "never-before-encountered dangers" that needed to be carefully studied.

  • NASA was concerned about the physical abilities of astronauts during high-G launch and re-entry, testing whether they would have the strength to reach critical instrument panels.

  • Astronauts were also tested for visual changes in zero gravity, with instruments like eye charts installed in the capsules to monitor any issues.

  • The use of chimpanzees as test subjects before human astronauts was seen as a "blow to their ego", highlighting the unique psychological factors involved with human spaceflight.

  • Modern astronauts must have the ability to tolerate boredom and low stimulation during routine missions, a psychological attribute not required of mechanical equipment.

Simulating the Cosmos

Simulations and mock-ups on Earth are crucial for preparing astronauts for the challenges of space travel. These environments visually and tactically mimic real space scenarios, allowing astronauts to practice tasks and gain familiarity with the outside of their spacecraft. For example, astronauts train for spacewalks by putting on their suits and rehearsing moves while floating in a neutral buoyancy tank, which simulates the sensation of weightlessness.

These simulations also help space agencies assess how astronaut candidates handle stress and isolation. Isolation chambers, like the one used by the Japanese space agency, allow observers to closely monitor applicants' behavior and group dynamics over an extended period. This provides valuable insights into their suitability for the confined, high-stress environment of space missions.

By extensively replicating the conditions of space travel on Earth, space agencies can better anticipate and address the unpredictabilities astronauts may face. These simulations are a crucial part of preparing both the technology and the human element for the rigors of space exploration.

Here are specific examples from the context that support the key insight about the extensive use of simulations and mock-up environments to prepare for the unpredictabilities of space:

  • NASA has "fifty in all—modules, airlocks, hatches, capsules" that are mock-ups to simulate different aspects of space travel and exploration. This allows astronauts to "visit space without leaving Earth" and practice tasks in a "slapstick-surreal make-believe edition" of space.

  • The Small Pressurized Rover simulator is an "orange Humvee" used at the HMP Research Station on Devon Island in Canada's High Arctic to simulate rover traverses on the moon. This "analog setting" resembles the moon's surface and allows NASA to test "performance and productivity" before using actual prototypes.

  • The Mars500 simulation at the Institute of Biomedical Problems in Moscow has "five locked, interconnected modules" that mimic a mission to Mars, including a "Martian Surface Simulator" module. This allows researchers to study the "perilous psychology of isolation and confinement" that astronauts would face.

  • Astronauts train for spacewalks by practicing in a neutral buoyancy tank, a "giant indoor pool" that simulates the experience of floating in space, even though it's "not exactly like floating in space."

  • Virtual reality training is also used to help prepare astronauts for the "sensation of free fall in space" that they cannot fully experience on Earth.

The key point is that these diverse simulations, mock-ups, and analog environments allow space agencies to anticipate and mitigate the unpredictable challenges of space travel and exploration, from technical systems to human psychology, before venturing into the actual cosmos.

Human Factors in Space

Space exploration demands careful consideration of human factors. Astronauts face unique psychological and physiological challenges that must be addressed.

Motion sickness is a prime example. The sensory conflict between the eyes and inner ear in zero gravity can induce nausea and vomiting, incapacitating crew members. Researchers have developed specialized equipment like rotating chairs to study and mitigate this issue.

Another key factor is the reorientation of sensory perception. Without gravity, astronauts' brains struggle to interpret signals from the inner ear, leading to disorientation and vertigo. This "Earth sickness" upon return can be disruptive.

Psychological impacts are also crucial. The overwhelming vastness of space can trigger "cognitive overload" and anxiety in some astronauts. Maintaining mental well-being during long-duration missions is essential.

Understanding and addressing these human factors is vital for the success and safety of space exploration. Rigorous research, training, and countermeasures are necessary to support astronauts in the unique environment of space.

Human factors must be a central consideration as space programs push the boundaries of human experience beyond Earth.

Here are key examples from the context that support the insight that space exploration requires consideration of human psychological and physiological responses:

  • The Soviet mission Soyuz 10 was aborted due to motion sickness, demonstrating how incapacitating motion sickness can be for astronauts.

  • Experiments at the U.S. Naval Aerospace Medical Institute in Pensacola, Florida subjected cadets to extreme rotational motion to induce motion sickness, showing researchers' efforts to understand and provoke this response.

  • The rotating chair experiment at NASA Ames, where the researcher could "make a rock sick", further illustrates the ability to induce motion sickness in a controlled setting.

  • Accounts of astronauts vomiting in space during the early days of spaceflight, with NASA footage avoiding showing this, highlight the prevalence of motion sickness.

  • The "Weightless Flight Regurgitation Phenomenon" coined by researchers to describe the challenges of eating and drinking in zero gravity demonstrates the reorientation of basic physiological functions.

  • Descriptions of astronauts experiencing "landing vertigo" or "Earth sickness" upon returning from space, as their brains have adapted to the lack of gravity, show the sensory reorientation required.

  • Discussions of "EVA height vertigo" and the difficulty of simulating the sensation of free fall in space training highlight the psychological challenges of space exploration.

  • Cosmonaut Vitaly Zholobov's experience of being "shocked" by the "bottomless abyss" of space and the "psychological/interpersonal difficulties" it caused exemplify the cognitive and emotional impacts of space.

Cultural Impact on Astronaut Selection

Cultural traits shape astronaut selection. Space agencies like the Japan Aerospace Exploration Agency (JAXA) consider national cultural tendencies when choosing astronauts. For example, the Japanese cultural emphasis on teamwork and emotional restraint are seen as advantageous for space missions.

The Japanese are accustomed to small living spaces and limited privacy, making them well-suited for the confined quarters of a space station. They are also typically polite and adept at suppressing emotions, which helps astronauts maintain harmony in close-knit crews.

However, this tendency towards emotional suppression can also be a liability. JAXA looks for astronaut candidates who can strike a balance - not becoming too depressed or explosive under stress. To address this, JAXA has its astronauts train with their more assertive American counterparts at NASA, helping them develop a healthy middle ground.

Cultural factors thus play a key role in astronaut selection, with space agencies carefully considering national traits that may enhance or hinder performance in the unique environment of space exploration.

Here are specific examples from the context that support the key insight that cultural traits influence astronaut selection:

  • The context notes that the "ideal astronaut" in Japan is someone who "takes direction and follows rules like an exceptionally well-behaved child." This reflects the Japanese cultural value of obedience to authority.

  • The story about the woman who waited until age 37 to get her ears pierced, despite her mother's objections, illustrates the Japanese cultural tendency to "suppress emotion and try to cooperate, try to adapt, too much."

  • JAXA psychologist Natsuhiko Inoue states that "Most Japanese will become depressive rather than explosive" when suppressing emotions, which is a concern for astronaut selection.

  • The context notes that JAXA looks for astronaut candidates who can "manage to achieve a balance" between expressing and suppressing emotions, as opposed to being too passive or too aggressive. This reflects the cultural preference for emotional restraint.

  • The context explains that JAXA astronauts train with NASA astronauts for years, during which "their character becomes somewhat more aggressive and like Americans." This suggests JAXA tries to adapt the Japanese cultural tendency towards emotional restraint to better fit the NASA astronaut model.

The Reality of Long-Duration Spaceflight

Long-duration spaceflight poses immense physical and psychological challenges for astronauts. The confinement and isolation of being in space for extended periods can take a heavy toll. Astronauts also face significant degradation of bone and muscle mass due to the lack of gravity. These issues must be carefully addressed to ensure the health and safety of astronauts on long-term missions.

The psychological strain of prolonged isolation and confinement in the cramped confines of a spacecraft can be immense. Astronauts must learn to effectively manage interpersonal dynamics and cope with the monotony and sensory deprivation of space travel. Failure to do so can lead to serious mental health issues.

Equally concerning are the physical effects of microgravity. Without the constant pull of gravity, astronauts experience rapid loss of bone density and muscle mass. This can severely impair their ability to function and even pose life-threatening risks upon return to Earth. Effective countermeasures, such as rigorous exercise regimes, are critical to mitigate these physiological impacts.

Overcoming the formidable obstacles of long-duration spaceflight requires comprehensive preparation and innovative solutions. Ensuring the well-being of astronauts, both physically and mentally, is paramount as humanity pushes the boundaries of space exploration.

Here are specific examples from the context that support the key insight about the physical and psychological challenges of long-duration spaceflight:

  • Eating and drinking in zero gravity: The context describes experiments where researchers found that in zero gravity, "water in a cup became 'an amoeboid mass' that would levitate from the cup and 'envelop' the face, causing a "sense of drowning." Eating was also perilous, with "pieces of food hang[ing] suspended in the oropharynx" and "bits of food float[ing] up over the soft palate into the nasal passages."

  • Urination in zero gravity: Researchers had to fashion "enclosed urine receptacles" for astronauts, as urinating into an open container would be "exceedingly messy" without gravity.

  • Bone and muscle loss: The context states that astronauts coming back from 6-month missions on the space station have "15 to 20 percent less bone" than when they left. Exercise countermeasures like treadmills only provide about 70% of normal weight-bearing, leading to "massive bone loss."

  • Psychological challenges: The context describes the "earth-out-of-view phenomenon" where the lack of Earth's presence can lead to "anxiety and depressive reactions, suicidal intention, or even psychotic symptoms." Astronauts also experience a "cognitive overload" from the vastness of space that can be overwhelming.

  • Reentry forces: During reentry, astronauts experience extreme G-forces, with one astronaut enduring "an overly steep, overly fast reentry and a full minute in 8 G's, about double the normal hypergravity of reentry." This can make it difficult to even move one's arms.

These examples illustrate the significant physical and psychological challenges that long-duration spaceflight poses for astronauts, supporting the key insight.

Space Exploration's Blend of Sublime and Ridiculous

Space exploration blends the sublime and the ridiculous. Astronauts witness breathtaking views of Earth and the cosmos, yet also grapple with mundane tasks like managing bodily functions in zero gravity. This juxtaposition reflects the complex, paradoxical nature of human endeavors in space.

On one hand, space offers awe-inspiring sights - "a beautiful shot of a full Moon against the black sky and the strato formations of the clouds of the earth below." Yet the same astronaut may soon be dealing with a crewmate "dumping urine." The sublime and the ridiculous coexist, erasing the line between them.

This blend extends to the preparations for space travel. Engineers must meticulously design equipment to sustain human life in the harsh environment, yet also account for the unpredictable quirks of the human body and psyche. Astronauts undergo intensive training, yet some tasks remain absurdly mundane, like reading eye charts during historic flights.

Ultimately, space exploration pushes the boundaries of human experience. It forces us to rethink what it means to be human when removed from the familiar conditions of Earth. The sublime and the ridiculous intertwine, creating a captivating, complex portrait of humanity's journey into the unknown.

Here are specific examples from the context that support the key insight that space exploration blends the sublime and the ridiculous:

  • Astronaut Jim Lovell captures "a beautiful shot of a full Moon against the black sky and the strato formations of the clouds of the earth below", which represents the sublime beauty of space. However, immediately after, his crewmate Frank Borman announces he is "dumping urine", representing the mundane and bizarre challenges of space travel.

  • The context describes how early NASA was concerned about how zero gravity would affect astronauts' vision and physical abilities. It mentions how John Glenn's capsule had a "scaled-down version of the classic Snellen eye chart" and other medical equipment, turning his historic first orbit into "like visiting the eye doctor" - a mundane task amidst the sublime experience of spaceflight.

  • The development of the Lunar Flag Assembly to make the American flag appear to be "flying in a brisk wind" on the airless moon represents the blend of technical ingenuity and patriotic symbolism in space exploration. The flag's initial failure to withstand the heat of the lunar lander's engine further illustrates the ridiculous challenges faced.

  • Experiments on early flights to understand how astronauts would eat and drink in zero gravity revealed "exceedingly messy" and "perilous" challenges, like "water in a cup becoming 'an amoeboid mass' that would 'envelop' the face" and "chewed food drifting up the esophagus into the mouth, causing vomiting." These mundane bodily functions take on a bizarre quality in the space environment.

  • The isolation chamber experiments at IBMP, where astronaut candidates are observed for a week, blend the sublime goal of space exploration with the ridiculous realities of human behavior and psychology under confinement, as evidenced by the "homosexual Ladies' Home Journal" tone of the research papers.


Let's take a look at some key quotes from "Packing for Mars" that resonated with readers.

Yes, the money could be better spent on Earth. But would it? Since when has money saved by government redlining been spent on education and cancer research? It is always squandered. Let's squander some on Mars. Let's go out and play.

The argument is that investing in space exploration, though costly, is a worthwhile endeavor. The counterpoint that the money could be better spent on Earth-based issues is countered by the notion that such savings are often misallocated anyway. Instead, it's suggested that allocating resources to space travel can be seen as a form of "splurging" on a grand adventure. This perspective views space exploration as a valuable pursuit in its own right.

To the rocket scientist, you are a problem. You are the most irritating piece of machinery he or she will ever have to deal with. You and your fluctuating metabolism, your puny memory, your frame that comes in a million different configurations. You are unpredictable. You're inconstant. You take weeks to fix. The engineer must worry about the water and oxygen and food you'll need in space, about how much extra fuel it will take to launch your shrimp cocktail and irradiated beef tacos. A solar cell or a thruster nozzle is stable and undemanding. It does not excrete or panic or fall in love with the mission commander. It has no ego. Its structural elements don't start to break down without gravity, and it works just fine without sleep.

To me, you are the best thing to happen to rocket science. The human being is the machine that makes the whole endeavor so endlessly intriguing.

In the eyes of a scientist, humans are complex and troublesome machines that require extensive care and attention. They have unpredictable needs, emotions, and physical limitations that make them difficult to work with. However, it is precisely these human flaws that make space exploration so fascinating and worthwhile. The human element adds a layer of intrigue and challenge to the endeavor.

Space doesn't just encompass the sublime and the ridiculous. It erases the line between.

In the vastness of space, the boundaries between grandeur and absurdity disappear. The extraordinary beauty of celestial bodies coexists with the mundane aspects of human existence, making it impossible to distinguish between the two. As a result, the experience of space travel becomes a complex blend of awe-inspiring moments and ridiculous challenges.

Comprehension Questions

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How well do you understand the key insights in "Packing for Mars"? Find out by answering the questions below. Try to answer the question yourself before revealing the answer! Mark the questions as done once you've answered them.

1. What are some of the physiological needs of humans that must be accommodated in space missions?
2. Why do astronauts present more challenges in space missions compared to mechanical parts?
3. How does the absence of gravity affect astronauts physically during space missions?
4. What kind of psychological factors make human spaceflight more complex than using mechanical parts?
5. What unique preparations are needed for humans before they undertake space missions?
6. What is the purpose of using neutral buoyancy tanks in astronaut training?
7. How do isolation chambers contribute to astronaut training?
8. Why are simulations crucial for preparing for space travel?
9. What role does the Mars500 simulation play in astronaut training?
10. How does virtual reality training benefit astronauts?
11. What physiological effect is caused by the mismatch between visual input and the inner ear's sensory signals in zero gravity?
12. Why do astronauts often experience disorientation and vertigo upon their return to Earth after a space mission?
13. How does being in space impact an astronaut's psychological state?
14. How does a cultural emphasis on teamwork and emotional restraint influence the selection of astronauts in certain space agencies?
15. Why might the ability to live comfortably in small spaces and with limited privacy be valued in astronaut candidates from certain cultural backgrounds?
16. What are the potential drawbacks of a cultural tendency towards suppressing emotions for astronauts, and how do some space agencies address this?
17. What are the main physical challenges faced by astronauts during extended periods in space?
18. Why are rigorous exercise regimes important for astronauts on long-term space missions?
19. What psychological challenges do astronauts encounter in the confined and isolated environment of a spacecraft?
20. How do astronauts experience both breathtaking and mundane aspects during their missions?
21. What does the juxtaposition of awe-inspiring sights and mundane tasks in space travel suggest about human endeavors in space?
22. How do engineers account for the unique conditions of space when designing equipment for astronauts?
23. In what ways does space exploration challenge our understanding of what it means to be human?

Action Questions

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"Knowledge without application is useless," Bruce Lee said. Answer the questions below to practice applying the key insights from "Packing for Mars". Mark the questions as done once you've answered them.

1. How can you apply the principles of accommodating diverse needs, as required in space missions, to improve inclusivity in your workplace or community?
2. What strategies can you develop to better prepare and respond to unpredictable situations in your personal or professional life, inspired by the adaptability needed in space exploration?
3. How can learning about the physiological and psychological complexities of astronauts inspire you to take better care of your own health in challenging environments?
4. How can you create simulation environments in your professional or educational setting to enhance learning and prepare for unforeseen challenges?
5. How can you implement strategies to manage physiological and psychological stressors in environments different from your daily routine?
6. How could you incorporate the value of teamwork and emotional restraint in your professional or personal life to improve collaboration and reduce conflicts?
7. How can individuals and organizations apply principles from astronaut training and stress management to improve their own resilience and teamwork in high-pressure environments?
8. What changes can you make to remain grounded while pursuing ambitious goals?

Chapter Notes


  • Astronauts are the most challenging "machinery" for rocket scientists: Astronauts are unpredictable, inconstant, and require extensive accommodations (food, water, oxygen, etc.) compared to stable, undemanding machines like solar cells or thruster nozzles.

  • Space exploration is a "preposterous but captivating undertaking": Taking organisms evolved for Earth and suspending them in the harsh environment of space is a fascinating challenge that requires rethinking and relearning everything we take for granted on Earth.

  • Simulating space on Earth: There is a "slapstick-surreal make-believe edition" of space exploration, with mock-ups, simulations, and training exercises that allow people to experience aspects of space travel without leaving Earth.

  • The flag on the moon: The placement of the American flag on the moon was a complex endeavor, requiring extensive planning, engineering, and testing to overcome the challenges of the lunar environment (lack of atmosphere, low gravity).

  • The human side of space exploration: The focus is not just on the heroics and adventure, but also the small comedies and everyday struggles of astronauts, such as worrying about personal bodily functions or dealing with equipment malfunctions.

  • Redefining "normal": Space exploration is an exploration of what it means to be human, as astronauts must forgo and redefine many aspects of normal life for extended periods.

  • The sublime and the ridiculous: Space exploration blurs the line between the sublime (the beauty of the Earth and Moon) and the ridiculous (dealing with bodily functions), highlighting the complex and multifaceted nature of the human experience in space.


Here are the key takeaways from the chapter:

  • Isolation Chambers and Astronaut Selection: JAXA uses isolation chambers to observe astronaut candidates for a week and assess their behavior, teamwork, leadership, and conflict management skills, which cannot be easily evaluated in a one-on-one interview. This is in contrast to NASA, which does not use isolation chambers.

  • Origami Crane Test: The candidates are tasked with folding 1,000 origami cranes during the isolation period. This test allows JAXA to assess the candidates' patience, accuracy, and ability to maintain performance under increasing pressure as the deadline approaches.

  • Shift in Astronaut Attributes: The ideal astronaut has shifted from the "right stuff" of bravery, aggressiveness, and virility to a focus on interpersonal skills, adaptability, and the ability to function well in a confined, monotonous environment. Astronauts today are more likely to be "nerds" than "heroes."

  • Importance of Teamwork and Conflict Management: With larger crews and longer missions, astronauts need to be able to work well with others and manage conflicts, rather than relying solely on individual bravery and skill.

  • Japanese Cultural Traits and Astronaut Selection: The Japanese are seen as well-suited for life on a space station due to their cultural tendencies towards politeness, emotional restraint, and adaptability. However, JAXA is concerned that this can lead to suppressed emotions and passive-aggressive behavior, which they aim to balance through training with NASA astronauts.

  • Stress Testing and Unexpected Challenges: JAXA and NASA use unexpected challenges, such as delayed meals or malfunctioning toilets, to assess how candidates cope with stress and uncertainty, as these are important skills for astronauts.

  • Astronaut Selection as a Political Process: Factors such as English proficiency and military/aviation background can play a role in astronaut selection, as space agencies seek candidates who will integrate well with existing crews and have political connections.

  • Isolation and Confinement as Major Stressors: The psychological challenges of isolation and confinement in a sterile, confined environment are major concerns for space agencies, as they can exacerbate the usual stresses of the astronaut's job.


Here are the key takeaways from the chapter:

  • Isolation and confinement experiments: Space agencies conduct isolation and confinement experiments to study the psychological effects on people trapped in small, artificial environments for extended periods. These experiments, such as the Mars500 simulation, aim to understand and mitigate the negative impacts of isolation.

  • Challenges of isolation and confinement: Isolation and confinement can lead to a range of psychological issues, including irrational antagonism, depression, and sexual frustration. Factors like lack of privacy, sleep deprivation, and monotonous living conditions contribute to these problems.

  • Crew selection and training: Space agencies try to select and train astronauts to cope with the challenges of isolation and confinement, such as ensuring good communication skills, resilient humor, and cross-cultural understanding. However, some issues are difficult to anticipate or prevent.

  • Stigma and secrecy: Space agencies are reluctant to publicly acknowledge the psychological problems that can arise during space missions, fearing it could jeopardize funding and public support. This leads to a culture of secrecy and reluctance among astronauts to seek help.

  • Monitoring and detection: To address the issue of astronauts hiding psychological problems, space agencies are exploring technologies to automatically detect signs of stress or depression, such as monitoring facial expressions and speech patterns.

  • Importance of the natural environment: Astronauts and other isolated individuals deeply miss the natural environment of Earth, including sights, smells, and the ability to freely move around. This contributes to the psychological challenges of being in a confined, artificial environment.

  • Sexuality and relationships: The lack of intimate relationships and sexual outlets is a significant concern for long-duration space missions. Space agencies have considered allowing non-monogamous couples or even providing artificial sexual aids, though these ideas raise ethical and practical challenges.

  • Crew composition: There is debate about the optimal crew composition for long-duration space missions, with some advocating for mixed-gender or even married couples to help mitigate the psychological stresses, while others argue this could introduce new risks.


  • Psychological Concerns about Space Travel: There were significant concerns among psychologists and space agencies about the potential psychological impact of space travel, particularly the "breakaway effect" - a feeling of detachment from Earth experienced by some high-altitude pilots. There was worry that this could lead to panic, psychosis, or even sabotage of the mission.

  • Astronaut Euphoria and Reluctance to Return: Early spacewalkers like Alexei Leonov and Ed White experienced a sense of euphoria and reluctance to return to the spacecraft, which caused concern for mission control. This "space euphoria" was a phenomenon that NASA psychologists had warned about.

  • Challenges of Spacewalking: Astronauts faced significant physical and psychological challenges during spacewalks, including "EVA height vertigo" - a paralyzing fear of the vast expanse of space below them. Returning to the spacecraft could also be extremely difficult, as seen with Leonov's struggle to re-enter the airlock.

  • Psychological Impacts of Long-Duration Spaceflight: The "earth-out-of-view phenomenon" was a concern for long-duration missions to Mars, as the complete loss of sight of Earth could lead to a range of psychological issues like anxiety, depression, and even psychotic symptoms.

  • Cosmonaut Experiences: The chapter recounts the experiences of cosmonauts like Boris Volynov and Vitaly Zholobov, who faced equipment failures and psychological stress during their missions. Volynov's near-death experience during re-entry highlights the extreme physical and mental challenges of space travel.

  • Importance of Rhythm and Rest: The psychologist Rostislov Bogdashevsky emphasized the importance of maintaining a healthy rhythm of work and rest for cosmonauts, noting that the lack of this rhythm can lead to physical and psychological exhaustion.


Here are the key takeaways from the chapter:

  • The Birth of American Space Exploration: The chapter describes a pivotal moment in the early days of American space exploration, when scientist David Simons was tasked with launching a monkey named Albert on a V-2 rocket to study the physiological effects of weightlessness. This marked the beginning of efforts to understand the challenges of sending humans into space.

  • Gravity's Fundamental Role: The chapter provides an in-depth explanation of the nature of gravity, highlighting its critical role in shaping the universe, maintaining the Earth's atmosphere and water, and enabling life. This context helps explain the profound uncertainty and concern that scientists had about the potential dangers of removing gravity's influence.

  • Parabolic Flights and Early Weightlessness Experiments: The chapter describes the development of parabolic flight techniques, pioneered by the Haber brothers, which allowed scientists to study the effects of weightlessness on animals and human subjects in a more controlled and cost-effective manner compared to rocket launches.

  • Challenges of Eating and Drinking in Zero Gravity: Early experiments with human subjects in parabolic flights revealed unexpected and concerning challenges related to eating and drinking in the absence of gravity, such as food and water behaving in unpredictable ways and causing choking and vomiting.

  • Urination in Zero Gravity: Researchers also studied the ability of human subjects to urinate normally in zero gravity, leading to the development of specialized urine receptacles to address the challenges posed by the lack of gravity.

  • Overcoming Initial Concerns: Despite the widespread concerns and anxiety about the potential dangers of weightlessness, the chapter highlights the more optimistic perspective of test pilots like Joe Kittinger, who embraced the opportunity to experience and study zero gravity firsthand, ultimately helping to allay many of the initial fears.

  • Ongoing Zero Gravity Testing: The chapter notes that modern space agencies continue to use parabolic flights to test equipment and train astronauts, demonstrating the enduring importance of understanding the effects of weightlessness on both human physiology and technology.


Here are the key takeaways from the chapter:

  • The Reduced Gravity Office at Ellington Field oversees a NASA program where students compete to conduct zero-gravity research on a modified C-9 military transport jet. This program allows students to experience and study the effects of microgravity and reduced gravity environments.

  • NASA's facilities are filled with an abundance of safety warnings and precautions, even for minor workplace hazards. This is likely a coping mechanism to deal with the major threats of space travel, such as explosions, crashes, and depressurization.

  • Experiencing weightlessness during the parabolic flights on the C-9 jet is described as a "subtle physical euphoria" and "like floating in air without effort, without help, without resistance." Astronauts have described it as feeling like a natural way to exist, compared to the sensation of walking with shoes on Earth.

  • Zero-gravity environments present unique challenges for equipment and machinery. Things like fuses, computers, and even basic tasks like setting something down become problematic without the effects of gravity. NASA must extensively test all equipment in microgravity conditions before use in space.

  • The human body also faces challenges in zero gravity. Organs float freely within the torso, and even simple bodily functions like exhaling can cause issues without proper ventilation. Astronauts must adapt to these physical changes during their time in microgravity.

  • The Missouri University of Science and Technology team's welding experiment on the C-9 flight faced technical difficulties, with a broken weld on their experiment cart. This highlights the unpredictable nature of conducting research in zero-gravity environments.


  • Motion Sickness is Caused by Sensory Conflict: Motion sickness occurs when the visual system (eyes) and the vestibular system (inner ear) provide conflicting information to the brain about the body's movement and orientation. This sensory conflict can lead to nausea and vomiting.

  • Head Movements Exacerbate Motion Sickness: Sudden or frequent head movements are highly "provocative" for motion sickness, as they cause the otoliths (calcium pebbles) in the inner ear to ricochet back and forth, further confusing the brain.

  • Adaptation is Key for Astronauts: Astronauts in space experience the "visual reorientation illusion", where up and down become disoriented. Adapting to this new sensory environment is crucial, as delaying adaptation can lead to severe motion sickness.

  • Vomiting in Spacesuits is Dangerous, but Survivable: While vomiting in a spacesuit during a spacewalk was once thought to be fatal, modern spacesuits are designed to safely expel vomit away from the astronaut's face and breathing apparatus. However, it remains a serious concern due to potential vision obstruction and lung damage from acidic stomach contents.

  • Motion Sickness was Stigmatized in the Early Space Program: Admitting to motion sickness was seen as a weakness among astronauts, leading some, like Frank Borman, to hide their symptoms. This attitude has since shifted, as motion sickness is now recognized as a common and natural response to the novel sensory environment of space.

  • Excess Gravity Poses Serious Risks: Astronauts experience increased gravity forces during launch and reentry, which can cause blood to pool in the lower body, depriving the brain of oxygen and leading to blackouts. Lying down during these high-G events helps mitigate this risk, but it also makes it difficult for astronauts to move and operate controls.

  • Motion Sickness Research Continues: Despite decades of research, the exact mechanisms behind motion sickness are still not fully understood. Researchers continue to study ways to prevent and mitigate the effects of motion sickness, both for astronauts and other individuals exposed to novel motion environments.


Here are the key takeaways from the chapter:

  • Crash Simulation and Cadaver Testing: The chapter describes a crash simulation facility at the Transportation Research Center in Ohio, where NASA collaborates with researchers to test the Orion space capsule's landing impact on cadavers and crash test dummies. This allows them to study the forces and potential injuries astronauts may experience during a water landing.

  • Multiaxis Crash Forces: Space capsule landings involve forces along multiple axes (lateral, transverse, and longitudinal), which can be unpredictable, especially with the added factor of landing in the ocean. This is similar to the complex forces experienced in a race car crash, which serves as a useful model for designing astronaut restraint systems.

  • Astronaut Physiology and Restraint Challenges: Astronauts face unique challenges compared to race car drivers due to their reclining position, the need to accommodate a wide range of body sizes, and the presence of bulky spacesuit components. This makes designing an effective restraint system that also allows for quick egress a complex engineering problem.

  • Historical Perspective on Human Testing: The chapter contrasts NASA's current discomfort with using cadavers in testing to the more cavalier approach taken during the Apollo era, when human volunteers were subjected to high-G impact tests, sometimes sustaining injuries. This highlights the evolving ethical considerations around the use of human subjects in aerospace research.

  • Debate over the Necessity of Astronauts: The chapter touches on the ongoing debate about whether astronauts are truly necessary, given the successful use of chimpanzees in early space capsule testing, which highlighted that the capsule, not the astronaut, controls the flight.


Here are the key takeaways from the chapter:

  • The Careers of Ham and Enos: Ham and Enos were chimpanzees who flew the dress rehearsals for the first U.S. suborbital and orbital flights in 1961. Their careers were in some ways not far off from those of the first American astronauts, Alan Shepard and John Glenn, as they underwent similar training and preparation for spaceflight.

  • Concerns about Spaceflight: NASA had significant concerns about the effects of spaceflight, particularly weightlessness and high G-forces, on both humans and chimpanzees. They wanted to ensure astronauts could function properly in space and reach the instrument panels during launch and reentry.

  • Chimp vs. Astronaut Perception: The fact that chimpanzees flew before the astronauts was seen as a blow to the astronauts' egos, as it implied they were no more than "glorified chimps." There was tension and a lack of mingling between the chimp and astronaut teams.

  • Ham's Fame vs. Enos's Unpopularity: Ham was a media sensation and beloved by the public, while Enos was seen as mean and unpopular. The public was more interested in Ham's story than Enos's.

  • Enos Misconceptions: Rumors and stories emerged about Enos's behavior during his spaceflight, including claims that he masturbated in front of the cameras. These stories were unfounded and the product of rumor and speculation.

  • Ham's Burial and Memorial: There was confusion and debate over how to properly memorialize Ham after his death, with the Smithsonian's plan to stuff and display him sparking public outrage. He was ultimately given a "hero's burial" in front of the International Space Hall of Fame.

  • Potential Chimp Lunar Mission: There were reports in the early 1960s that NASA and the Air Force were considering sending a chimpanzee on a one-way mission to the moon, potentially before a human astronaut. However, the evidence for this is inconclusive, and it seems more likely that the chimps were being trained for Gemini-related tasks rather than a lunar mission.

  • The Role of Humans vs. Robots in Space Exploration: There is an ongoing debate about the relative merits of human and robotic exploration of space, with some arguing that robots are more cost-effective for specific scientific tasks, while others believe humans bring unique capabilities like intuition and adaptability that are valuable for broader scientific exploration.

9 NEXT GAS: 200,000 MILES

Here are the key takeaways from the chapter:

  • Simulated Lunar Rover Traverses: NASA is conducting simulated lunar rover traverses on Devon Island in Canada's High Arctic, which closely resembles the lunar surface, to test the performance and productivity of their new pressurized rover prototypes before actual deployment.

  • Challenges of Lunar Exploration: Lunar exploration poses unique challenges, such as dealing with the abrasive and electrostatically charged lunar dust, which can damage equipment and pose health risks if inhaled. Astronauts also need to carefully plan their traverses to ensure they can safely return to the base within their oxygen and battery life constraints.

  • Importance of Analog Testing: Conducting analog tests on Earth, such as the simulated traverses on Devon Island, allows NASA to identify and address issues before actual lunar missions, including determining the optimal size of exploration parties, the time required to complete tasks, and the need for greater autonomy for astronauts.

  • Lessons Learned from Apollo: The Apollo missions demonstrated the value of careful planning and preparation, but also the need to balance this with a willingness to take calculated risks and adapt to unexpected situations. The current NASA approach of extensive rehearsing and planning is a response to the challenges faced during Apollo, but there are concerns that it may have become overly cautious.

  • Importance of Interdisciplinary Collaboration: The success of lunar exploration requires the collaboration of various disciplines, including planetary scientists, engineers, and support staff (e.g., the cook). Effective communication and coordination between these different groups is crucial for the success of the missions.

  • Psychological Factors in Exploration: The psychological well-being of astronauts is an important consideration, as extended periods of isolation and limited autonomy can negatively impact their morale and performance. Providing astronauts with more autonomy and flexibility in their work schedules may help address these issues.


Here are the key takeaways from the chapter:

  • Gemini VII was a medical dress rehearsal for the Apollo lunar program: NASA wanted to study the effects of prolonged spaceflight on astronauts, as no astronaut had spent more than 8 days in space at that point. They conducted experiments on "minimal personal hygiene" to understand how astronauts would fare during a 2-week mission.

  • Astronauts experienced significant body odor and skin issues during prolonged spaceflight: The experiments found that astronauts' body odor reached a "maximum height" after 7-10 days, due to the buildup of sweat, grease, and dead skin cells. Skin issues like folliculitis and boils also developed.

  • Clothing absorbs a significant amount of bodily emissions: The Soviet experiments found that 86-93% of the men's skin oils and sweat were absorbed by their clothing, rather than accumulating on their skin. This helped explain the hygiene practices of the 16th-17th centuries, when people would change their undergarments frequently instead of bathing.

  • Lack of gravity mitigated some hygiene issues: Lovell noted that the zero-gravity environment of Gemini VII prevented the chafing and irritation that the Air Force subjects experienced, as the astronauts' clothes did not get as saturated with sweat and pressed against their skin.

  • Developing effective space hygiene solutions was a challenge: NASA and the Soviets experimented with various shower and cleaning systems for space stations, but they were largely unsuccessful. Astronauts today rely on wet wipes and rinseless shampoos instead of traditional showers.

  • Skin and scalp issues were common, but not always recognized as problematic: Borman experienced "terminal dandruff" that was likely just an accumulation of dead skin, while Lovell's son joked that his father orbited the Earth in his underwear.


Here are the key takeaways from the chapter:

  • Bed Rest as a Spaceflight Analog: Bed rest studies are used by space agencies to mimic the effects of weightlessness on the human body, particularly the thinning of bones and atrophy of muscles. Participants in these studies, known as "terranauts", are paid to remain in bed for extended periods to help researchers understand and develop countermeasures for these physiological changes.

  • The Body's Adaptation to Disuse: The human body is designed to maintain muscle and bone mass in proportion to the demands placed on it. When these demands are reduced, as in the case of bed rest or spaceflight, the body responds by dismantling the excess bone and muscle, a process controlled by specialized cells called osteoclasts and osteoblasts.

  • Limitations of Exercise Countermeasures: While exercise is generally recommended to maintain bone and muscle health, the effectiveness of exercise countermeasures in space has been limited. Devices like treadmills and vibration plates have shown mixed results, and researchers are still searching for more effective ways to prevent the significant bone and muscle loss experienced by astronauts during long-duration missions.

  • Genetic Factors in Bone Health: Certain genetic factors, such as the higher bone density of Black individuals, may make some people more resistant to the effects of disuse on bone health. This has led to discussions about the potential for selecting astronauts with favorable genetic profiles for long-duration missions, such as an "all-Black" crew for a Mars mission.

  • Hibernation as a Potential Countermeasure: Researchers have explored the possibility of using human hibernation as a way to reduce the physiological demands and resource requirements of long-duration spaceflight. However, significant challenges remain in terms of safely inducing and maintaining human hibernation for extended periods.

  • Intimate Aspects of Bed Rest Studies: Bed rest studies address sensitive topics such as personal hygiene, bodily functions, and sexual activity, which are often overlooked or avoided in discussions of spaceflight. The chapter provides insights into how these issues are handled in the context of these studies.


  • Mating in Zero Gravity is Challenging: The chapter discusses the difficulties of sexual intercourse in zero gravity, as the lack of gravity makes it challenging for the partners to stay coupled. Astronauts and marine biologists have not been able to observe successful mating in zero gravity conditions.

  • Dolphin Mating Involves a Third Dolphin: The chapter debunks the myth of the "Three Dolphin Club" - the idea that dolphins require a third dolphin to help with mating in zero gravity. The author's research indicates that only two dolphins are required for mating, and the dolphin's prehensile penis helps the male stay coupled with the female.

  • NASA Avoids Addressing Sex in Space: The chapter suggests that NASA does not explicitly address the issue of sex in space, as it could lead to public outrage and funding cuts if discovered. Astronauts are aware of the risks and are unlikely to engage in sexual activity during missions.

  • Weightlessness May Affect Human Reproduction: The chapter discusses the potential effects of weightlessness on human reproduction, including the impact on sperm motility, egg fertilization, and fetal development. Studies on rats have shown that weightlessness can affect uterine contractions during birth, which are important for the newborn's physiological adjustments.

  • Limited Research on Reproduction in Space: The chapter notes that research on the effects of weightlessness on human reproduction has been limited, as it has not been a high priority for space agencies compared to other physiological systems. The funding for such research has also been declining in recent years.


Here are the key takeaways from the chapter:

  • High-Altitude Skydiving Risks: Skydiving from extremely high altitudes (23 miles up) poses significant risks, including the inability to control body position due to lack of air resistance, the potential for spinning and resulting centrifugal forces that could be fatal, and the challenge of maintaining stable body position and deploying parachutes at supersonic speeds.

  • Escape Systems for Astronauts and Spacecraft: Developing effective escape systems for astronauts during launch, reentry, and emergency situations is an extremely complex challenge. Existing technologies like ejection seats, inflatable crew escape pods, and parachute systems all have limitations and drawbacks in terms of protecting astronauts at the extreme speeds and altitudes involved.

  • Windblast and Hypoxia Dangers: Bailing out from high-altitude aircraft or spacecraft exposes individuals to severe windblast effects, which can cause facial deformation, tissue damage, and even death at speeds over 500 mph. Additionally, the lack of oxygen at high altitudes can lead to rapid loss of consciousness and death within minutes.

  • Felix Baumgartner and the Red Bull Stratos Mission: Baumgartner, an experienced skydiver and BASE jumper, is testing a modified emergency escape suit for the Red Bull Stratos Mission, which aims to gather data on human performance and survival at the extreme altitudes and speeds involved in a high-altitude space jump. The mission is sponsored by Red Bull as a way to promote the brand's image of "pushing limits" and "making the impossible happen."

  • Jon Clark and the Columbia Disaster Investigation: Jon Clark, the medical director for the Red Bull Stratos Mission, was previously involved in the investigation of the Columbia space shuttle disaster, where he and the team examined the remains of the crew to determine the causes of their deaths, including a shock wave phenomenon called "shock-shock interaction" that can fragment astronauts at hypersonic speeds.


  • Astronaut Toilet Training: Astronauts must undergo extensive training to learn how to properly use the space toilet, which is significantly different from a regular toilet on Earth. This training is overseen by Scott Weinstein, who teaches astronauts everything from how to sit on the toilet to how to ensure proper "separation" of waste in zero-gravity.

  • Space Toilet Design and Challenges: The space toilet is designed with a 4-inch opening, compared to the 18-inch opening of a regular toilet on Earth. This small size, combined with the lack of gravity, creates significant challenges in ensuring proper waste collection and disposal. Issues like "fecal popcorning" and "fecal decapitation" have plagued the design of space toilets over the years.

  • Fecal Simulants and Testing: NASA researchers have developed sophisticated fecal simulants, made from ingredients like refried beans and E. coli bacteria, to test the performance of space toilets. This is necessary because testing with real human feces is often taboo and difficult to obtain.

  • Gender Bias in Astronaut Selection: The challenges of waste management in space were a significant factor in the initial exclusion of women from the astronaut program. The inability of early space suits and waste collection devices to accommodate female anatomy was cited as a logistical concern that led to the selection of only male astronauts.

  • Psychological Importance of Space Toilets: Despite the technical challenges, the development of functional and comfortable space toilets was seen as crucial for the psychological well-being of astronauts. The ability to use a "sit-down commode" rather than the earlier fecal bags was an important factor in helping astronauts feel more "normal" and at-home during long-duration spaceflight.


  • Corned Beef Sandwich Incident: In 1965, astronaut John Young smuggled a corned beef sandwich from Wolfie's delicatessen onto the Gemini III capsule, which violated NASA's strict requirements for space food. This incident was criticized by Congress and led to a formal reprimand for Young.

  • Strict Requirements for Space Food: Space food had to be lightweight, compact, and have high caloric density to minimize weight and volume in the cramped spacecraft. It also had to be designed to avoid crumbs that could float around and interfere with the spacecraft's systems.

  • Aerospace Food Testing: NASA and the military conducted extensive testing of various space food formulations, including cubes, rods, slurries, and liquid diets, on volunteers confined in space cabin simulators. The goal was to assess the impact of these foods on digestive health and morale.

  • Veterinarians Influence on Space Food: Many of the early space food scientists were military veterinarians who were more concerned with cost, ease of use, and avoiding health problems than with making the food palatable for human consumption.

  • Waste Management Challenges: The early space programs were preoccupied with minimizing waste and its disposal, leading to a focus on "low-residue" foods that would reduce the frequency and volume of astronaut bowel movements.

  • Flatulence and Astronaut Selection: Researchers explored the idea of selecting astronauts based on their ability to produce low levels of flammable gases like methane and hydrogen, which could be a safety concern in the confined spacecraft.

  • Evolving Space Food Technology: Over time, space food has become more normal and palatable, with the introduction of thermostabilized meals in plastic pouches. However, future long-duration missions to Mars may require a return to more specialized and potentially unappetizing food formulations.


Here are the key takeaways from the chapter:

  • Recycling Urine and Waste for Sustenance: The chapter discusses how astronauts on long-duration space missions, such as a trip to Mars, would need to recycle their urine and other waste products to obtain drinkable water and potentially even food. This process, known as "sustain-ability engineering", is a necessary part of human spaceflight and is seen as a new environmental paradigm.

  • Psychological Barriers to Recycling Waste: Despite the technical feasibility of recycling urine and waste, there are significant psychological barriers to its acceptance, even among the general public. The chapter highlights how people are often reluctant to consume water or food derived from recycled waste, a phenomenon known as the "toilet to tap" aversion.

  • Innovative Proposals for Space Food and Nutrition: The chapter explores some of the more unconventional proposals made by scientists and engineers in the past for providing food and nutrition to astronauts on long-duration space missions, such as eating mice, hydrolyzed proteins from clothing, and even shredded paper.

  • The Value of Manned Spaceflight to Mars: The chapter grapples with the question of whether a manned mission to Mars is worth the significant cost, estimated to be around $500 billion. It argues that while the practical scientific benefits may not be immediately apparent, the inspirational and symbolic value of such an endeavor is important, akin to the first manned hot-air balloon flights.

  • The Difference Between Simulation and Reality: The chapter contrasts the experience of engaging with simulated space environments, such as virtual tours or theme park attractions, with the actual experience of being in space. It emphasizes that the physical, emotional, and sensory aspects of spaceflight cannot be fully replicated in a simulated environment.

  • The Nobility of the Human Spirit: The chapter suggests that the pursuit of ambitious, impractical, and expensive goals, such as a manned mission to Mars, can be seen as a manifestation of the nobility of the human spirit, even if the practical benefits are not immediately clear.


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