1. Can Humans Survive Mars’ Radiation?
Mars lacks a global magnetic field and has only a thin atmosphere, which means its surface is exposed to galactic cosmic rays and solar energetic particles. Data collected by the Radiation Assessment Detector aboard NASA’s Curiosity rover, published in Science in 2013, quantified the radiation environment during transit to Mars and on the Martian surface. The findings showed that astronauts would receive a significant cumulative dose during a round-trip mission, increasing long-term cancer risk.
Researchers are studying shielding strategies to reduce exposure. One widely supported approach involves burying habitats beneath several meters of Martian regolith. Modelling studies published in Life Sciences in Space Research indicate that regolith shielding can substantially lower radiation doses to levels closer to those experienced aboard the International Space Station. Underground lava tubes, identified through orbital imaging, are also being evaluated as natural shelters. Radiation risk remains a major challenge, but it is considered technically manageable with proper habitat design.
2. How Would Humans Breathe?
Mars’ atmosphere is about 95 per cent carbon dioxide and far too thin to breathe. However, NASA demonstrated a key proof of concept in 2021 with the Mars Oxygen In Situ Resource Utilisation Experiment (MOXIE) aboard the Perseverance rover. Results published in Science Advances in 2022 confirmed that solid oxide electrolysis can convert carbon dioxide into oxygen reliably under Martian conditions.
MOXIE produced oxygen at a rate of several grams per hour, sufficient only for demonstration. Scaling up the system would require larger reactors and sustained power. Oxygen would serve both as breathable air and as an oxidiser for rocket propellant. Engineers describe MOXIE as a foundational step toward in situ resource utilisation, which reduces the need to transport consumables from Earth.
3. Where Would Water Come From?
Water is essential for drinking, hygiene, agriculture, and fuel production. Orbital instruments and radar data have confirmed widespread water ice on Mars, particularly near the poles and in subsurface deposits at mid latitudes. A 2018 study published in Science reported radar evidence of a subglacial lake beneath the south polar ice cap, reinforcing the conclusion that significant ice reserves exist.Future missions are expected to land near accessible ice deposits. Extracted water can be purified and then electrolyzed into hydrogen and oxygen for fuel. Life support systems aboard the International Space Station already recycle approximately 90 percent of water from humidity and urine. These closed-loop systems serve as prototypes for Mars habitats. The presence of water ice makes sustained habitation more plausible than previously believed.
4. Can Humans Tolerate One Third Gravity?
Mars’ gravity is lower than Earth’s but higher than microgravity in orbit. Long term exposure to microgravity on the International Space Station leads to bone density loss, muscle atrophy, and cardiovascular changes. Research published in NPJ Microgravity documents these physiological effects in detail.
No human has yet experienced Mars gravity for extended periods, so direct data do not exist. Scientists expect that one third gravity may mitigate some microgravity related decline, but countermeasures such as resistive exercise and pharmacological interventions will still be required. Artificial gravity habitats created through rotation have also been proposed as a long term solution. While uncertainty remains, current evidence suggests that health impacts could be managed with appropriate medical and engineering support.
5. How Would Settlers Stay Warm and Powered?
Mars is cold, with surface temperatures frequently dropping below minus 100 degrees Celsius at night. Solar power is viable but vulnerable to dust accumulation and global dust storms. The 2018 storm that ended the Opportunity rover mission demonstrated the risk of prolonged sunlight reduction.
To provide reliable energy, NASA developed the Kilopower nuclear fission system, successfully tested on Earth in 2018. Compact reactors could generate steady electricity independent of sunlight. Continuous power is essential for life support, oxygen production, heating, and communication. A combination of nuclear and solar systems with battery storage is widely viewed as the most robust architecture.
6. What About Toxic Dust and Long Term Sustainability?
Martian soil contains perchlorates, which are chemically reactive compounds that can interfere with thyroid function in humans. A 2016 study in the International Journal of Astrobiology analyzed toxicological risks and emphasized the need for dust mitigation systems.
Habitats would require airlocks, filtration systems, and possibly soil processing techniques to remove hazardous compounds. For long term sustainability, closed ecological life support systems are under development. Experiments on the International Space Station have demonstrated plant growth in controlled hydroponic systems. These systems recycle carbon dioxide into oxygen and provide fresh food. In situ resource utilization strategies also include using local materials for construction and fuel, reducing dependence on Earth resupply.
Conclusion
Mars presents serious hazards: radiation exposure, unbreathable air, scarce liquid water, reduced gravity, extreme cold, and chemically reactive dust. However, each of these challenges has at least one research supported mitigation strategy. Radiation can be reduced through shielding, oxygen can be produced from carbon dioxide, water can be extracted from ice, power can be supplied through nuclear reactors, and life support systems can recycle air and water efficiently.
Significant uncertainties remain, particularly regarding long term health effects and psychological resilience during isolation. Yet based on current scientific evidence and engineering demonstrations, survival on Mars is technically plausible. Mars will not be comfortable; it will require complex infrastructure and constant maintenance. But from a scientific standpoint, human survival there is no longer a speculative idea. It is a question of sustained technological development and commitment.