What is Space Oncology?
​Space oncology (SO) is a rapidly emerging field that investigates how microgravity (MG) and cosmic radiation influence cancer progression and treatment. Space-based environments are being studied to accelerate tumour modelling and drug discovery, making space a unique laboratory for cancer biology.
Space oncology has already generated important conceptual and technological spin-offs, ranging from three-dimensional cell culture systems and protein crystal studies for cancer drug development to advances in radiation biology, tissue-response research and biomarker discovery.​

Effects of Microgravity on Cancer Cells
Reviews of both real-space and simulated microgravity experiments have demonstrated important effects on cell adhesion, migration, proliferation, gene expression and the formation of multicellular spheroids. Microgravity alters cytoskeletal organisation and promotes spheroid formation, creating more physiologically relevant tumour models that may accelerate drug discovery while reducing reliance on animal models.
The effects of microgravity on cancer cells, cancer stem cells and drug response may also help shape future therapeutic strategies. Microgravity enables the production of more uniform protein crystals, lower-viscosity biologics and more stable pharmaceutical formulations.
Microgravity also influences the formation of nanoparticles that deliver chemotherapy directly to tumours while enabling controlled drug release. It alters cancer cell morphology, membrane behaviour and gene expression, thereby influencing how cells take up therapeutic agents. When gravity is removed or substantially reduced, cells experience profound changes in fluid dynamics, mechanical loading and cell-to-cell interactions. For cancer cells, these changes are far from trivial. They also facilitate the production of drug crystals and biologic formulations that are difficult to manufacture under normal terrestrial conditions.

Graf et al. discussed in detail the effects of microgravity on multiple omics disciplines in their paper Omics Studies of Tumor Cells under Microgravity Conditions, summarising transcriptomic, proteomic, metabolomic and epigenetic findings across multiple tumour types exposed to both real and simulated microgravity.
Similarly, Grimm et al., in their paper Recent Studies of the Effects of Microgravity on Cancer Cells and the Development of 3D Multicellular Cancer Spheroids, demonstrated how microgravity alters cell adhesion, proliferation, survival, cytoskeletal organisation, extracellular matrix interactions and spheroid formation, with important implications for drug discovery and the reduction of animal experimentation.
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Mechanobiological Diversity of Cancer
Cancer is biologically diverse. Understanding the differing mechanobiological responses of tumour cells to microgravity may help identify signalling pathways that are fundamental to metastasis, tissue invasion and treatment resistance.
Studies have demonstrated cytoskeletal reorganisation, altered focal adhesion signalling, changes in extracellular matrix interactions and the spontaneous formation of multicellular spheroids, all of which are highly relevant to tumour progression and therapeutic response. Microgravity not only alters the biology of tumour cells targeted by drugs but may also improve the performance of advanced drug-delivery systems, including nanoparticles and three-dimensional formulations.
Studies conducted aboard the International Space Station have investigated both real-space and simulated microgravity across breast, lung, thyroid, prostate, melanoma, glioblastoma and haematological cancer models. Cancer cells exposed to microgravity and the unique radiation environment of space behave differently from those grown under conventional laboratory conditions. These differences continue to reveal biological mechanisms that are otherwise difficult to observe and may ultimately contribute to improved cancer therapies.

Breast and Gastrointestinal Cancer in Outer Space
​Breast cancer cells demonstrate changes in gene expression, morphology, signal transduction and invasive behaviour under microgravity. Experimental studies suggest that, under microgravity conditions, some breast cancer cell lines adopt a less aggressive phenotype. Under normal gravity, breast cancer cells attach firmly to the surrounding extracellular matrix through focal adhesions. In space, however, these adhesion complexes fail to mature fully, reducing the cells' ability to migrate and metastasise.
Key proteins involved in cell-cycle regulation, including cyclin D1 and cyclin B1, are significantly downregulated, slowing cell division and reducing the rapid colony-forming capacity of tumour cells. Breast cancer spheroids grown in space have also shown increased susceptibility to certain targeted therapies.
Gastrointestinal and colorectal cancers, however, appear to respond differently to microgravity, with some studies suggesting accelerated tumour progression and a more aggressive phenotype. Reduced expression of drug-resistance genes, increased DNA and RNA damage markers, and reorganisation of F-actin have also been reported, making gastric cancer cells more sensitive to doxorubicin.
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FDA and Space Oncology
​The U.S. Food and Drug Administration (FDA) does not have a separate approval pathway for drugs developed using space-based research. Rather than focusing on where an experiment was performed, the FDA evaluates how well it was conducted. Space-derived evidence must therefore be scientifically rigorous, reproducible and generated in accordance with accepted preclinical standards. The FDA assesses whether the submitted data are credible, relevant and sufficient to support claims of safety and effectiveness within the existing regulatory framework.
In 2025, the FDA approved a subcutaneous formulation of pembrolizumab. NASA had contributed to the underlying protein crystal growth research performed aboard the International Space Station, targeting the ADAR1 gene. The resulting protein crystals were more uniform and better suited to formulation studies supporting this route of administration.
Similarly, rebecsinib became the first space-tested cancer drug to enter clinical trials. Following successful International Space Station-linked testing, it received U.S. FDA Investigational New Drug (IND) status. Tumour organoids grown in microgravity demonstrated sufficient antitumour activity to support further regulatory progression.
Together, the pembrolizumab and rebecsinib examples illustrate that space-based research is becoming a legitimate component of modern drug development rather than simply a scientific curiosity.
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New Regulations and Investment
​In 2026, UK regulators and the UK Space Agency publicly supported the development of a regulatory pathway for pharmaceutical research conducted in outer space. Investors and regulators alike have recognised the need for clear legal and quality standards governing commercial space-based biomanufacturing.
The Medicines and Healthcare products Regulatory Agency (MHRA), the Civil Aviation Authority (CAA) and the Regulatory Innovation Office (RIO) have worked together to streamline inter-agency regulation. In doing so, they have addressed many of the "dual-regulation" challenges that previously discouraged major commercial investment in space-based pharmaceutical manufacturing.
In microgravity, protein crystals and complex biologics form more slowly and uniformly because they are not affected by gravitational sedimentation. This allows companies such as BioOrbit to engineer highly stable, concentrated cancer therapies that may ultimately be administered as subcutaneous injections rather than lengthy intravenous infusions.
BioOrbit's BOX unit, launched in May 2026, is a microwave-sized autonomous orbital manufacturing platform designed to crystallise protein-based drugs under microgravity conditions. Following £9.8 million in seed funding, the company is using BOX to develop cancer therapies that can be delivered by self-injection at home rather than requiring prolonged hospital-based infusions.
Instead of launching entire manufacturing facilities into orbit, companies can now deploy compact autonomous production units capable of operating independently in space.
The UK is leveraging its £2 billion Life Sciences Sector Plan to position itself as a global centre for commercial space-enabled biomanufacturing.
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Economics of Space Oncology
With this background, it is essential that we begin planning for the future rather than focusing only on the low-hanging fruit. Despite a relatively modest US$13 billion space economy, ISRO has emerged as the world's third-largest space technology power and ranks among the five major government space agencies. As launch costs continue to fall and commercial space platforms become more widely available, space oncology is becoming an increasingly realistic proposition.
Launch costs have fallen dramatically, from approximately US$50,000 per kilogram in the early 2000s to less than US$2,500 per kilogram on the SpaceX Falcon 9 in 2025, making space-based pharmaceutical manufacturing significantly more viable. With the continued growth of successful commercial space companies in India, these costs may decrease further.
Space manufacturing is no longer confined to research. BioOrbit's BOX platform, Varda Space's manufacturing capsules and emerging UK regulatory frameworks demonstrate that the industry is moving from proof-of-concept towards commercial production.
Although space-based cancer drug development remains more expensive than conventional terrestrial research, the potential benefits are considerable. Improved disease models and more predictive preclinical testing may reduce drug-development failure rates by as much as 10%, potentially saving around US$100 million per successful drug. Space experiments currently cost approximately US$2 to 8 million on the International Space Station, or US$10 to 15 million using commercial re-entry capsules, compared with roughly US$10,000 to US$500,000 for comparable terrestrial preclinical studies.
The microgravity pharmaceutical manufacturing market, valued at approximately US$1.5 billion in 2025, is projected to reach US$9.8 billion by 2034, representing a compound annual growth rate of 23.7%. Commercial space stations and nano- and microsatellites (CubeSats) are rapidly becoming essential research platforms, while smaller, more frequent launches are making pharmaceutical payloads increasingly practical.

Epilogue
​More than 700 peer-reviewed papers, 40 book chapters and 12 monographs have already been published in the field of space oncology. I am optimistic that, during my grandchildren's generation, cancer management on terra firma will increasingly benefit from research undertaken, and medicines developed, in outer space.
Confucius could well have been referring to space oncology when he observed more than 2,000 years ago:
"A journey of a thousand miles begins with a single step."
Humanity will continue to exploit the unique environment of outer space in its enduring quest to solve the cancer conundrum here on Earth.
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Further Reading
​Readers wishing to explore this rapidly developing field may find the following resources of interest:

• Graf et al. Omics Studies of Tumor Cells under Microgravity Conditions
• Grimm et al. Recent Studies of the Effects of Microgravity on Cancer Cells and the Development of 3D Multicellular Cancer Spheroids
• U.S. Food and Drug Administration (FDA): Oncology Drug Development
• BioOrbit
• UK Government Life Sciences Sector Plan

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When I was seven or eight years old, looking at videos of the cosmos would move me to tears. Growing up in Batticaloa, a city in the Eastern Province of Sri Lanka, the concepts of astronomy and space exploration were almost entirely foreign. Like many Asian households, the traditional path of becoming a doctor was the one most spoken about and encouraged by teachers and society.
Yet, an unexplainable pull toward the stars grew inside me. Back then, I didn't even know the word “astronaut”—I just told people I wanted to be a “scientist” because that was the only word available to me in my hometown.
A turning point came when my grandfather bought me my first computer. While other kids were playing games, my search history was filled with the ambient sounds of planetary atmospheres. By the 7th and 8th grades, I was completely hooked. Without the AI tools we have today, and with nothing but a basic Google search bar, I began hunting for NASA student competitions and online astronomy programs entirely on my own.

The Struggles of an Isolated Dream
My home is what I fondly call a “small, lovely birdhouse.” It is just me, my mom, and my dad. We don't live around extended family, and the bond we share is incredibly deep. My mother is the strongest woman I have ever known; she does everything for me. Her love is so fierce that even now, during my university years, she cries every single time I have to leave home, even if it is just for a single day.
Because they love me so deeply, my parents were initially terrified of my interest in space. In the capital city of Colombo, parents might have access to physical guidance, planetariums, and space camps for their children. But in Batticaloa, I was entirely alone.

Editorial Introduction
At InnovaSpace, we explore how advances in space medicine can improve health both in space and on Earth. Research has shown that microgravity can influence the behaviour of cancer cells, making cancer an important area of investigation for both space exploration and terrestrial medicine.
With that in mind, we are honoured to share this deeply personal article by our friend and colleague Dr Krishnan Ganapathy, originally published in The Hindu. His reflections, written from the unique perspective of both surgeon and patient, remind us that behind every diagnosis is a human story. We thank him for allowing us to reproduce his article and send him our very best wishes for his continued treatment and recovery.

How it all began
March 2,7.30 a.m. I had initiated the act of micturition (urination), possibly for the100,000time in the past 75 years. Ten seconds had passed. I saw 2 ml of diluted ‘coke’ in the urine stream. In that split second I realised that this was a breakdown of blood products, a condition known as haematuria. I recollected surgery classes taken 55 years ago, where the lecturer said – “When an elderly person passes blood there are only 3 diagnoses - a) malignancy b) malignancy c) malignancy.”
​In 1970, there was no ultrasound; cystoscopy was not routinely available. We were taught that if malignancy was not picked up, it meant investigations were insufficient and were told to keep investigating. Trained in that era, the thrill of making an early clinical diagnosis took over. I did not dwell on dire implications, should I be right, nor did I make any prayers that I should be wrong. Cool, calm, composed and totally asymptomatic, I did a literature search. Every article, and every chapter concluded that “malignancy had to be excluded”. Two days later I saw diluted ‘coke’ in my urine again. Within 48 hours, I got myself investigated.

Diagnosis confirmed
An outpatient cystoscopy was scheduled. Within 15 seconds I saw on the screen an obviously malignant tumour. Three minutes later, on my way to the consultant’s room, I told my wife with pride: “See I was absolutely right. Hi-grade malignancy confirmed”. Fifty-eight years of managing thousands of serious and critical head injuries, bleeding in the brain and brain tumours had probably resulted in my nonchalance. Or maybe reality had not dawned yet, and I was fooling myself.
The uro-oncologist outlined different management options. I was to be on the dais ata major international conference the following week. My brain interjected: “Time you learn to let go– look, the cancer cells are multiplying every second, get operated on immediately; management depends entirely on the detailed biopsy.”

Immediate response
A normal reaction on being told that one has a hi-grade cancer could vary from shock, disbelief, fear, denial, anxiety, distress, anger, sadness, rage, guilt, frustration and withdrawal. “A bolt from the blue”, “the ground fell away” or “my world collapsed” iswhat is expected – particularly in an individual with outstanding physical and mental health. In my case I was reconfirming a self-diagnosis. My occupation, education, socioeconomic background, access to current knowledge and access to state-of-the-art resources resulted in a different response – within 10 minutes, I started the paper work, fixed a date and time of surgery, and informed my family.
But then, I am also human. Every now and then I broke down with my lacrimal glands going into overdrive unashamedly. I gave vent to my anger and frustration. My spouse of 51 years stood firm as the rock of Gibraltar. When I threw away the high protein nutritious food painstakingly prepared with love and affection she only smiled – knowing that it was the malignant cells responding, not her husband. I recollected a quote widely attributed to Dr. Henry Maudsley that appears in Boyd’s textbook of Pathology -- “The sorrow which has no vent in tears, may make other organs weep.”

What the Numbers Actually Say
This is not a distant hypothetical. NASA's Exploration Medical Capability (ExMC) element of the Human Research Program has been modeling the probability of medical events during long-duration and exploration missions for years. Their probabilistic risk assessment framework, which draws on ISS medical event records, Shuttle mission data, and analog environment studies, consistently points toward the statistical near-certainty of significant medical events during a Mars mission of the expected duration. Traumatic injury has been explicitly identified by NASA as the highest medical concern for mission success. Every extravehicular activity, every spacecraft maintenance procedure, every moment of work in a pressurized suit accumulates risk. Over a three-year mission, that cumulative exposure translates directly into probability.

Cardiovascular diseases remain one of the leading causes of mortality worldwide, demanding diagnostic and therapeutic strategies that are not only accurate but also personalised. As healthcare shifts toward precision medicine, aptamer-based technologies are emerging as powerful tools with the potential to revolutionise how cardiac diseases are detected, monitored, and treated.

​Aptamers, short single-stranded DNA or RNA molecules, are engineered to bind specific targets such as proteins, cells, or biomarkers with high affinity and selectivity. Often described as synthetic alternatives to antibodies, aptamers offer several advantages, including low immunogenicity, high stability, cost-effective synthesis, and ease of chemical modification. These features make them particularly suitable for integration into next-generation diagnostic and therapeutic platforms.

In the context of cardiac diseases, early detection is critical. Conditions such as myocardial infarction, heart failure, and atherosclerosis rely on timely identification of biomarkers like troponins, C-reactive protein (CRP), and B-type natriuretic peptide (BNP). Aptamer-based biosensors enable highly sensitive and rapid detection of these biomarkers, even at very low concentrations, offering the potential for earlier diagnosis compared with some conventional approaches. When integrated with portable platforms such as paper-based assays or smartphone-assisted devices, these systems can deliver point-of-care diagnostics, reducing the need for centralised laboratory infrastructure. These innovations maybe particularly valuable in remote or resource-constrained environments, including spaceflight medicine, where rapid point-of-care cardiovascular monitoring is essential.

​Beyond diagnostics, aptamers are also gaining attention in targeted therapy. Their ability to specifically bind disease-related molecules allows them to act as drug delivery agents or therapeutic inhibitors. Although not a cardiovascular therapy, Pegaptanib, an RNA-based aptamer approved by the FDA in 2004, demonstrates the therapeutic viability of aptamer technologies and supports exploration of similar cardiovascular applications. For example, aptamers may be designed to block clot formation pathways or target inflammatory mediators involved in cardiovascular disease progression.

Exposure to spaceflight, particularly microgravity, induces profound physiological alterations that compromise neuromusculoskeletal and cardiovascular systems. These changes lead to muscle atrophy, bone demineralization, postural instability, and other functional deficits. Physiotherapy and related countermeasures, including tailored exercise regimens and structured rehabilitation protocols, are central to mitigating these effects during and after space missions.
Spaceflight imposes unique stressors on the human body due to the absence of Earth’s gravitational load, leading to systemic physiological adaptations. While space agencies have developed exercise countermeasures to moderate deconditioning, astronauts still face significant health challenges both during missions and upon return to Earth’s gravity. Physiotherapy plays a critical role in preparing, supporting, and rehabilitating astronaut health through evidence-based interventions.

Neuromusculoskeletal Deconditioning
Prolonged microgravity exposure leads to pronounced muscle atrophy and bone density loss, especially in weight-bearing structures such as lower limbs and the spine. Astronauts can lose significant muscle strength and up to 1–2% of bone mass per month without consistent loading stimuli. These changes parallel muscle atrophy and deconditioning observed in terrestrial patients subjected to prolonged immobilisation.
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Sensorimotor and Postural Control Deficits
Spaceflight results in impairments in postural control and dynamic gait performance due to altered vestibular inputs and neuromuscular coordination. Astronauts show significant decrements in balance and sensorimotor function upon return to Earth, comparable to the effects seen in bed-rest analog studies.
In microgravity and related analog environments, discrepancies may arise between actual body position and perceived orientation.
(A) When sensory inputs are aligned, posture is maintained with accurate perception of body position.
(B) Under conditions of reduced or conflicting sensory input, such as limited visual feedback, a mismatch can occur between actual and perceived orientation. The individual may physically lean in one direction while perceiving a lean in the opposite direction. Despite this discrepancy, stability can still be maintained.
Such orientation illusions are commonly observed on entry into weightlessness and depend on the available sensory information. In the absence of visual input, tactile cues become dominant in determining perceived orientation. Interpretation of foot pressure and support loading may therefore lead to an incorrect perception of body position.

​When we think of human spaceflight, it’s easy to focus on rockets, spacecraft and mission timelines. Less visible, but just as critical, is the quiet disruption of the body’s natural rhythms. On board the International Space Station, astronauts witness multiple sunrises and sunsets every day, challenging circadian systems that have evolved under a single 24-hour light–dark cycle. Sleep, hormonal regulation, cognition and overall wellbeing all depend on rhythm. The below article written by Dr Maria Helena Itaqui Lopes, originally published in the journal Zero Hora and website GZH, explores rhythm from a clinical and musical perspective, and reminds us that the language of the body matters deeply, whether on Earth or in orbit.

​One day, while studying the biography of Herbert von Karajan, the legendary conductor regarded as one of the greatest in the history of conducting and often referred to as the “conductor of conductors”, I was struck by his reflections on rhythm. He stated that “if no one teaches students the basic disciplines of rhythm, things become impossible”. Although this statement, coming from a musician, may at first seem to relate exclusively to music, in reality rhythm goes far beyond this. It encompasses a sense of balance in physical movement, mental processes, learning, self-care, daily activities and vital energy.

​Our bodies function rhythmically. We need only recall cardiac rhythm, breathing, sleep, digestive function and circadian rhythms, among many others. Of the biological rhythms that regulate bodily function, the circadian rhythm stands out as a central example, as it organises hormonal release in a time-dependent manner. The secretion of cortisol, melatonin, growth hormone and insulin follows patterns that influence metabolism, immune response, cognitive performance and tissue repair. In preventive medicine, recognising these rhythms allows functional variations to be interpreted, the timing of assessments to be guided, and interventions to be individualised.

​Still within the scope of preventive medicine, the starting point for a health review is not defined by age-related calendars nor by the presence of symptoms, but rather by the early recognition of functional changes, taking family history and genetics into account. Beginning an assessment at this stage means respecting an individual’s biological timing, interpreting subtle functional signals and anticipating risks before disease becomes established. In this way, the clinical review becomes a strategy of continuous, personalised care, aimed at preserving autonomy and health over time.

​These notions of the body’s own language interact with our daily activities. Returning to music, we know that a large proportion of Baroque works were written at a tempo of 75 to 80 beats per minute, measured by a metronome (a device used by musicians to regulate tempo by setting beats per minute), which corresponds closely to the average resting heart rate considered normal. It could be said that this synergy is pleasing to most people.

​A medical consultation also has its own rhythm, which is sometimes forgotten or even never learned. A consultation has a beginning, a development, a moment of climax and a conclusion. Expressing empathy either too early or at an inappropriate moment disrupts this balance, and the doctor–patient relationship becomes misaligned. Entering the correct frequency to properly understand a patient is a skill that requires a basic sense of rhythm. An andante tempo (a musical term referring to tempos between 72 and 84 beats per minute) closely resembles our heart rate and therefore feels comfortable to us. In other words, at the start of a consultation or during a visit to a patient in a hospital bed, the encounter should follow a rhythm that conveys safety and support from the doctor. This is a skill that should be better recognised and valued by professionals. From the patient’s perspective, the choice of when to undertake a clinical review should be carefully considered and planned for the new year that is beginning.

​Another, rather striking, story related to rhythm concerns three conductors who died while conducting the third act of Wagner’s opera Tristan and Isolde. The pauses in this passage are intermittent and irregular, creating tension that can affect both mind and body. Karajan, aware of this and seeking to protect himself, would dissipate this intense tension by using breathing movements to distance himself from the musical strain.
In life, as in music, it is essential to find the right rhythm for each challenge, especially when it comes to caring for one’s own health.

When humans eventually set foot on Mars, they’ll face a medical challenge that rarely needs to be thought about on Earth - TIME. A radio signal between Earth and Mars can take 4 to 24 minutes to travel one way. That means if an astronaut sends a question to Mission Control, it could be more than 40 minutes before they receive a reply, which in an emergency situation is far too long to wait.
To close this gap, NASA and Google are working together on something called the Crew Medical Officer Digital Assistant (CMO-DA), an artificial intelligence system for space medicine designed to support astronauts when Earth is too far away to give immediate help. Think of it as a “medical copilot” that will not replace doctors, but instead will help the crew diagnose and manage problems step-by-step using knowledge adapted specifically to space medicine.

Unlike a standard chatbot, the CMO-DA can work with multiple kinds of input. Astronauts might type or speak questions, upload vital signs, or share images from a portable ultrasound. The system then offers possible causes, highlights urgent warning signs, and suggests treatments that match the very limited supplies they have available to them. The big difference from Earth-based systems is that it’s trained with information that reflects spaceflight medical challenges, such as fluid shifts in low gravity, the increased risk of kidney stones, or how certain drugs behave differently in space.
To test its usefulness, NASA and Google have been running the assistant through structured scenarios. These use the same exam style that medical students face, called Objective Structured Clinical Examinations, where candidates are judged on how well they manage a case. The early results look promising, with the AI decision support tool giving safe, reliable advice, and it helps astronauts approach a situation more clearly under stress.

This project is part of NASA’s broader plan for Earth-Independent Medical Operations. For deep-space missions, it has long been recognised that crews need a much higher degree of autonomy, since communication with Earth may be delayed or even cut off entirely—for example, when Mars is hidden behind the Sun. A tool like the CMO-DA gives astronauts a way to stabilise and treat a patient without waiting for ground communication.
It’s important to remember that the system is meant as support and not as an authority. Ultimately, the astronauts in-situ remain the decision-makers. The assistant provides structured checklists, reminders, and treatment suggestions. It can also document everything that was done and prepare a clear report so that, once communication is restored, doctors on Earth can follow-up what happened and advise on next steps.

The future will bring new features, with researchers aiming to link the assistant to onboard sensors, wearables, and imaging devices, and to test it in Mars analogue missions on Earth. The goal is a complete medical system—crew, tools, and smart software working together to make medical autonomy on Mars a reality.
This technology, however, isn’t just for astronauts. It could also benefit people in remote communities on Earth, where medical access and connectivity are limited. In that way, a tool built for Mars missions medical support might improve healthcare for millions here at home.
NASA and Google’s project shows how AI in aerospace medicine is shifting from science fiction into practical support for space medicine—with potential benefits reaching well beyond Mars.

Microbes are generally associated with infection, and the usual response to their mere presence is to eradicate them as quickly as possible. For example, the “no-rinse soap” used during space travel mainly consist of antimicrobials, i.e. chemicals that kill microbes, with the aim to remove bacteria on the skin.
It is correct that microbes can cause disease, but it is microbes that created an environment and an atmosphere on Earth that allow plants and animals to exist. Microbes are literally everywhere, and we ourselves depend upon microbes to keep our external facing surfaces healthy and to help with the breakdown of food in our gut and production of substances that our body needs. The microbes form actual communities with thousands of species in and on us, for example the gut, respiratory and skin microbiomes, and these communities collaborate with our immune systems.

​To give an idea of their importance, data suggest that it is the pollution from antimicrobials that is the primary responsible for climate change because their impact is very broad and reduces the microbial diversity and changes the microbial balance. Similarly, studies indicate that antibiotics have long-term impact on our health, and they have been shown to increase the frequency of cancer, diabetes, asthma as well as functional impairments in children’s development, immune function, and cognition. Poor gut health, which usually means an unbalanced and low diversity microbiome, has also been associated with mental health problems including depression and anxiety as our gut microbiome is responsible for producing substances needed for normal brain function.
On the International Space Station skin issues and problems with wound healing have been reported. Microgravity and radiation have generally been assumed to be responsible for this and the fact, that “no-rinse-soap” is a cocktail of antimicrobials, has received practically no attention. Antimicrobials are traditionally used for treating wounds, but the US FDA reported in 2016 and again in 2022 that they are ineffective in treating wounds, and studies have demonstrated that antimicrobials directly impair healing and that a healthy wound microbiome is required for healing to take place. These novel conclusions banning antimicrobials in skin care and wound healing are further supported by the positive findings with a new technology, MPPT (micropore particle technology), which acts by regulating the wound microbiome without killing anything. MPPT has been able to achieve 100% wound closure rates, including in complicated wounds and in people with impaired immune function. This observation shows that approaches that support the collaboration between the microbes and the immune system can be much more effective than the traditional, old blanket-bombing approach of eradicating all microbes, which renders the skin debilitated and less resilient.

These observations are relevant to space travel, in terms of both the environment onboard and clothing, food and methods of ”washing”. Our bodies have evolved on Earth, where microbes were and are present, and our evolution has benefited from this as the microbes assist in protecting our surfaces and in delivering nutrients and critical compounds needed for our health. This dependence persists, even if we decide to leave Earth for shorter or longer periods of time. It is therefore a necessity, particularly for deep space travel, which does not permit us returning to Earth periodically to update our microbiome, to develop environments and procedures onboard that can sustain our microbial requirements.
These considerations are based on an article recently published in Frontiers in Public Health, which focuses on the role of antimicrobials in causing climate change from severely damaging the Earth’s microbiome. The impact of antimicrobials on the Earth microbiome and the microbiome inside a space station are comparable as they are both closed systems. It is consequently important to consider the essentiality of the microbial environment, when planning human life outside the Earth’s environment.

Bone plays an important role as a structure that supports the body and stores calcium. It retains fracture resistance by remodelling through a balance of bone resorption and formation.
Bones are usually dense and strong enough to support your weight and absorb most kinds of impact. As you age, bones naturally lose some of their density and their ability to regrow/remodel themselves.

​In a microgravity environment, because of reduced loading stimuli, there is increased bone resorption and no change in or possibly decreased bone formation, leading to bone mass loss at a rate of about ten times that of osteoporosis. Life in the microgravity environment of space brings many changes. Loss of bone mass is particularly noticeable because it affects an astronaut’s ability to move and walk upon return to Earth’s gravity.
Human spaceflight was once a fantasy only to be found in between the pages of a novel or on movie screens, however, now it is almost a tangible reality. Humans are going to spend more time in space. The human body is intrinsically adapted to Earth’s gravity, so exposure to conditions of reduced gravity, or microgravity can cause complications in many normal bodily functions. Microgravity decreases the effort required for movement.The length of space missions—and consequently the amount of time astronauts spend in orbit—has increased since humans began exploring space. Space travellers are exposed to numerous stressors while in space.
The reduced mechanical loading of weight-bearing bones caused by microgravity (μg) leads to bone loss in humans, especially in long-term space missions. As previously mentioned, this bone loss results from increased bone resorption and either unchanged or decreased bone formation, as observed in various human studies conducted both in space and during bed rest. Microgravity causes calcium to be released from bones, which suppresses parathyroid hormone (PTH) and lowers circulating levels of 1,25-dihydroxyvitamin D, although concentrations of 25-dihydroxyvitamin D remain adequate. This process reduces calcium absorption in the body.

The decrease in bone formation is associated with impaired osteoblast function and increased osteocyte apoptosis. Physical exercise using devices such as treadmills and resistive exercise equipment can help reduce the negative impact of microgravity on bones and muscles. Weight training and aerobic exercise are designed to simulate the mechanical loads normally exerted by gravity on Earth.
Proper nutrition and the use of supplements—such as vitamin D and calcium—are important to support bone health during and after a space mission. Rehabilitation programs include structured physical exercise, physical therapy, and nutritional monitoring to ensure optimal recovery. Together, these countermeasures aim to preserve musculoskeletal health in space and promote a successful transition back to Earth's gravity. Continued research is essential to refine these strategies for longer missions, such as those to the Moon or Mars.​