How Engineers Are Preparing for The First Human Mission to Mars

The idea of sending humans to Mars has long been a science fiction staple, but these days it’s looking like it might become a reality. NASA, SpaceX, and ESA are spearheading the pursuit of a human mission to Mars, with a target date of the 2030s.

As this long timeline suggests, the road to Mars isn’t exactly a simple one. Figuring out how to safely deliver human astronauts to the Red Planet means facing some of the toughest engineering problems ever explored in space exploration, while gaining a deeper understanding of Mar’s environment, challenges, and the potential hazards explorers may face.

With multiple agencies and companies working to design a spacecraft reliable enough to make the long journey to Mars, the question of how to engineer a vessel suited for such an arduous mission is a matter of debate.

Both SpaceX's Starship and NASA's Orion spacecraft are currently in development, each using unique engineering solutions to tackle the challenges of a Mars mission.² Starship is being explicitly designed for Mars missions and needs to carry large payloads and passengers while providing reusability to reduce costs, while NASA’s Orion craft is part of their deep space exploration program, Artemis, which includes, but is not limited to, Mars missions.

To make the journey possible, engineers at both NASA and SpaceX are working to create improved propulsion systems, testing both chemical rockets and nuclear thermal propulsion, which could provide greater fuel efficiency and reduce travel time. Finding alternate propulsion solutions could make long-duration missions such as a Mars flight more feasible, allowing spacecraft to travel faster and conserve fuel.

But the question of propulsion isn’t the only challenge of designing a spacecraft that’s ready to go to Mars. For such a long durational mission, the craft must also be prepared for the challenges of deep space. Engineers are actively working on finding methodologies for in-space refueling to ensure that spacecraft can be topped off with fuel once in orbit, making it possible to extend missions without needing to launch fuel from Earth. 

Since astronauts will be in deep space, exposed to harmful cosmic rays and solar radiation during the months-long journey, engineers are also developing radiation shielding technologies. Protecting the crew from these radiation sources will be essential to ensuring their health and safety on the way to Mars – and after.

Unlike the International Space Station (ISS), which receives regular resupply missions from Earth, a Mars-bound spacecraft must be able to operate independently for years. This means that a successful Mars mission will require the development of a self-sustaining life support system capable of providing air, water, and food for the crew, while supporting their psychological well-being.

Advanced Life Support Technologies

To reduce dependence on Earth during the long journey to Mars, life support systems must be highly efficient and fully regenerative.

One critical technology currently in development is closed-loop oxygen recycling, which would convert the carbon dioxide exhaled by astronauts back into breathable oxygen.⁴ NASA’s Environmental Control and Life Support System (ECLSS), which is currently used on the ISS, recycles about 50% of CO₂ into oxygen. However, due to their duration, Mars missions will require a system with near 100% efficiency, presenting a critical challenge for life support systems engineers.

Like air, water is another critical resource. Onboard the ISS, the ECLSS recycles 90% of wastewater, including urine and sweat, back into clean drinking water, but Mars-bound spacecraft will need even more efficient water filtration systems to ensure long-term sustainability. Some engineers have conceptualized the use of algae-based bioreactors to facilitate this process, which not only purifies water but also generates oxygen as a byproduct.

Once the trip is complete, astronauts will rely on in-situ resource utilization (ISRU) to extract their drinking water from underground ice and out of the planet’s thin atmosphere.⁵  NASA has run an experiment called MOXIE which successfully demonstrated that oxygen can be extracted from Martian CO₂, answering this critical question for establishing a sustainable human presence.⁶

Growing Food in Space

Questions of weight and space allocation means that it’s impractical, if not impossible, to transport years’ worth of food to the surface of Mars. This means that engineers will need to crack the code of Martian agriculture to allow astronauts to grow their own food supply. Engineers are upgrading traditional agricultural methods used on Earth with soil-free technologies like hydroponics, where plants grow in nutrient-rich water, and aeroponics, where plants grow in misted nutrients. Already tested on the ISS, these Mars-friendly methods use far less water and space than conventional farming.

NASA has been researching bioregenerative life support systems, which integrate plant growth with oxygen and water recycling, to help fulfill these nutritional needs. In these systems, plants absorb CO₂, release oxygen, and provide food, creating a miniature ecosystem that sustains the crew.⁷ Looking beyond conventional food sources may also provide a solution, as some experiments also suggest that algae and fungi could be used as a high-protein food source in space.

Plants aren’t the only thing that will need a carefully engineered environment to survive on Mars. Astronauts will need structures to live and work in, creating another challenge for engineers who are exploring inflatable and rigid structures to maximize efficiency and durability. 

One of the most promising techniques is 3D printing with Martian regolith, which is the scientific name for the loose soil and rock that covers the planet's surface.⁸ Experiments show that regolith can be mixed with polymers or melted into bricks using microwave or laser technology to create strong, lightweight materials for construction. Water could also be extracted from underground ice deposits and used to create Martian concrete by mixing it with regolith. This could help build stronger, longer-lasting habitats.

NASA and ESA have both conducted experiments using simulated Martian soil, demonstrating that 3D-printed habitats could be built using autonomous robotic systems, so astronauts will be ready to move in when their shuttle lands.

Radiation Protection

On Earth, we’re protected from harmful cosmic rays and solar radiation by our planet's atmosphere and global magnetic field. Mars naturally lacks these protective factors, meaning astronauts will face long-term exposure, which can lead to cancer, organ damage, and neurological disorders. Engineers are working to protect them with a number of strategies:

Reliable Power Sources for Sustained Mars Missions

Because Mars receives only about 50% of the sunlight that Earth does, astronauts will need a constant and reliable energy source to maintain the flow of power to life-support systems, research stations, and communication networks. These energy solutions must be highly efficient and resilient enough to stand against dust storms and long Martian nights.

Solar Power

Although Mars does get less sunlight than Earth, solar energy is still one of the most accessible and sustainable options for energy generation. Large solar panel farms can generate electricity during the day, storing energy in high-capacity batteries for use at night or during dust storms. However, these Martian dust storms, which occur regularly and can last for weeks or months at a time, significantly reduce sunlight exposure, posing a challenge for energy generation.

Nuclear Power

A more reliable energy source than solar power, nuclear power can operate continuously, regardless of weather conditions. NASA has been working to develop the Kilopower reactor, a small, portable nuclear fission system that can provide 10 kilowatts of power for at least 10 years.⁹ A small network of these reactors could support an entire Mars base, powering everything from oxygen production to water purification.

Wind and Geothermal Energy

While solar and nuclear power are the most popular candidates for power generation on Mars, some engineers are also exploring wind and geothermal energy as supplementary power sources. Geothermal energy could theoretically be harvested from underground heat sources, although more research is needed to determine if Mars has accessible geothermal reservoirs. While Mars’ thin atmosphere makes wind turbines less efficient than on Earth, there is evidence that local wind patterns could still generate some usable energy. 

Located on the slopes of Mauna Loa, Hawaii, HI-SEAS (Hawai’i Space Exploration Analog and Simulation)  is one of the most well-known training sites for Mars mission prep.¹⁰ This facility isolates crew members for months at a time in an atmosphere designed to simulate the rocky, barren terrain of Mars. Astronauts live in a confined habitat during missions, where they conduct spacewalks and experience the communication delays they would encounter on Mars, where signals take between 5 and 20 minutes to travel each way.

The Mars Desert Research Station (MDRS) in Utah, operated by the Mars Society, is another Mars training facility where astronauts practice scientific fieldwork, habitat maintenance, and emergency protocols in a Martian-like desert environment.¹¹

There are a number of similar projects around the world, including NASA’s Human Exploration Research Analog (HERA) and ESA’s Concordia Station in Antarctica, each of which provides valuable training in extreme isolation.^12,13 Practicing with these simulations helps potentially Mars bound astronauts self-sufficiency, as they are tasked with fixing equipment, growing food, and handling medical emergencies without outside assistance—just as they will on their future missions.

Physical Fitness & Adaptation to Low Gravity

Maintaining physical health during the mission is essential, as astronauts will be required to perform physically demanding tasks during their time on Mars, including habitat construction, scientific fieldwork, emergency repairs, and more. 

Mars only has 38% of the Earth’s gravity, which poses some unique challenges to the maintenance of physical well being.¹⁴ Spending a long amount of time exposed to lower gravity can lead to muscle atrophy, bone loss, and cardiovascular weakening—all of which have been observed in astronauts residing within the ISS’s microgravity.

All astronauts follow intensive strength and endurance training programs before their missions to counteract these effects, using resistance exercises, cardiovascular workouts, and flexibility training to ensure they are physically prepared. Some researchers are also currently exploring artificial gravity solutions, including the use of rotating spacecraft modules during transit, to help astronauts stay physically conditioned before arriving on Mars.

The length of their Mars sojourn means that astronauts will have to be especially disciplined in their training, exercising or at least two hours per day to maintain muscle and bone density while on the planet.

Robotics and AI will undoubtedly be essential to any human exploration of Mars. Robotic scouts can prepare landing sites and identify resources before humans arrive, while autonomous construction equipment could facilitate habitat assembly, and drones might aid in exploration and resource mapping. AI-assisted diagnostics and repairs could potentially help maintain equipment, reducing reliance on Earth-based support.

Robotic Scouts for Site Preparation and Resource Identification

Robots have already played a vital role in the early phases of Mars exploration. Robotic scouts, including Mars rovers like Curiosity, Perseverance, will likely be tasked with working autonomously to survey landing sites, analyze terrain, and identify areas that are suitable for human settlement before any astronauts will arrive. During the process, they will help mission planners determine the safest and most resource-abundant locations for habitat construction, assessing soil composition, radiation levels, water sources, and potential hazards.

NASA's Perseverance Rover is a key example of how rovers might assist with the human progress toward Mars.¹⁵ While working to discover signs of ancient life, Perseverance is paving the way for future astronauts by testing in-situ resource utilization (ISRU) technologies like MOXIE (Mars Oxygen ISRU Experiment). The discoveries it makes will provide future astronauts with critical information, enabling them to make data-driven decisions about where to build habitats or extract resources

Once Mars exploration begins, robotic scouts will likely be able to perform resource mapping using tools like spectrometers and thermal imaging devices to identify valuable resources like water, ice or minerals.

AI-Assisted Diagnostics and Repairs

A lot can go wrong on the long journey to Mars, but Artificial Intelligence might be able to help. AI systems integrated into a spacecraft’s maintenance and diagnostic systems might be able to  assist in diagnosing equipment malfunctions and suggesting appropriate corrective actions. For example they could help astronauts quickly identify issues with life support systems, communication tools, or propulsion systems without relying on long delays for communication with mission control.

Once any issues are identified, AI-powered systems might also guide astronauts through complex repairs. AI could simulate the repair process, provide step-by-step instructions, or even control robotic arms or drones that can perform remote repairs if critical systems malfunction. AI could work with robotic tools onboard in order to autonomously execute repairs.

AI could be a valuable tool on Mars missions because it is able to learn from past experiences and adapt over time, improving its performance and diagnostic capabilities. The more the system is used, the better it will become at troubleshooting, helping ensure that astronauts have reliable support when dealing with technical failures.

Drones for Exploration and Resource Mapping

Both aerial and ground-based drones could potentially provide invaluable support for exploration and resource mapping on Mars. 

Aerial drones like NASA’s Ingenuity helicopter might be used to scout difficult-to-reach regions, such as mountainous terrain, deep craters, or vast canyons, providing high-resolution imagery and environmental data.¹⁵ Ingenuity has already successfully flown in Mars’ thin atmosphere, conducting aerial reconnaissance alongside the Perseverance rover.  In the future, drones like Ingenuity might be equipped with advanced sensors to assist in identifying water ice, mineral deposits, and radioactive elements that could be used to support the astronauts’ survival.

We’ve already discussed rovers, another name for ground based drones, but it’s worth reiterating that they’ll be able to complement the work of their aerial counterparts by  navigating difficult surfaces and performing detailed analyses of soil and rock samples. In the future, ground based drones could assist in the extraction of Martian resources, such as water ice or minerals, which astronauts might use for life support systems or fuel production.

The Entry, Descent, and Landing (EDL) phase of a Mars mission will be one of the most critical and challenging stages of any spacecraft’s journey. Ensuring a safe landing of heavy payloads including scientific instruments and crew habitats requires overcoming significant technical hurdles.

Challenges of Landing on Mars

Mars presents a number of unique challenges when it comes to landing spacecraft safely:

Key EDL Technologies

Engineers are developing advanced Entry, Descent, and Landing, or EDL technologies to address these challenges, designed to safely and accurately land payloads on Mars. Here are some of the key EDL technologies currently under development:

Supersonic Retropropulsion

To create supersonic retropropulsion, rocket engines are used to slow down a spacecraft during  the descent phase, especially when the spacecraft is traveling faster than the speed of sound. It can provide the necessary deceleration in the thin Martian atmosphere, making it a critical tool for successful Mars landings.

In the Martian atmosphere, retropropulsion works by firing engines in the opposite direction of the spacecraft’s travel. This creates thrust, which slows the spacecraft down while it descends. When combined with parachutes and aerodynamic surfaces, retropropulsion can help slow the spacecraft enough to ensure a safe landing.

NASA's Perseverance Rover is a good example of how supersonic retropropulsion works in practice.  In the final stages of landing, the rover used two sets of engines to slow down, which helped ensure a controlled descent and a soft landing at the Jezero Crater, landing in a precision target area and avoiding dangerous terrain and obstacles.

Heat Shields

As a spacecraft enters the Martian atmosphere at high speed, the friction between it and the atmosphere generates extreme heat, which can damage or destroy the vehicle if not properly managed.  Due to this friction, heat shields are essential to surviving atmospheric entry. 

The primary technology used to create Mars bound heat shields is ablative heat shields, which are designed to burn away gradually as the spacecraft passes through the atmosphere. This effectively carries away the heat, preventing it from reaching the spacecraft’s interior and causing damage. 

NASA’s Perseverance Rover successfully used an ablative heat shield during its entry into the Martian atmosphere, which was designed to dissipate the intense heat generated by entry while remaining intact long enough for the spacecraft to slow down sufficiently for the parachutes to deploy.

Engineers are exploring even more durable and efficient heat shield materials for use in future manned missions. These include ceramic-based composites and refractory materials which are able to withstand higher temperatures and last longer during entry.

Precision Landing Systems

The development of precision landing systems has been one of the most important recent innovations in engineering a trip to MArs. Using  advanced sensors, guidance software, and algorithms to accurately pinpoint landing locations and ensure that payloads land within a defined zone, these systems are able to minimize the risk of landing in dangerous or unprepared terrain.

Modern landing systems rely on autonomous navigation, which relies on sensors such as LiDAR (Light Detection and Ranging), radar altimeters, and visual tracking systems to map the terrain below in real time to ensure the spacecraft lands where it’s supposed to. These systems ensure that the spacecraft avoids obstacles like rocks, cliffs, or deep craters by continually adjusting the spacecraft’s descent trajectory. During the final stage of descent, the spacecraft can adjust its position in midair using small, controlled thrusters to make micro-corrections, a vital technology for crewed missions, where landing near important resources, scientific targets, or safe zones is critical.

One example of this technology in use is the Terrain-Relative Navigation (TRN) that NASA’s Perseverance Rover employed T during its landing phase. TRN  used onboard images from cameras to identify specific terrain features and compare them with pre-loaded maps, which allowed the spacecraft to determine its exact position relative to the Martian surface.

Getting astronauts to Mars is tricky, but planning for the return trip to Earth is equally critical. The Mars return mission involves complex technical, logistical, and safety challenges, including launching from Mars, rendezvousing with an orbiting spacecraft, and executing a safe re-entry to Earth’s atmosphere. Ensuring the astronauts' safety during the entire mission is essential, so engineers must make contingency plans for emergencies and address the ethical considerations involved with the mission, especially if a one-way journey becomes necessary.

Mars Ascent Vehicle (MAV): Lifting Off from Mars

The Mars Ascent Vehicle (MAV) is the name for the spacecraft that will take off from the Martian surface, carry the crew to Mars orbit, and meet up with a return spacecraft that will return them to Earth.¹⁷ Building the MAV requires solving a number of unique engineering challenges including:

Rendezvous with Orbital Spacecraft

Once the MAV has ascended from Mars, it will meet up with a spacecraft known as the Mars Orbital Transfer Vehicle (MOTV), which will be waiting in orbit to transport the astronauts home to Earth.¹⁸ It will need to be equipped with life support systems to maintain the astronauts' health during the long journey back.

The rendezvous process will involve highly precise maneuvers to ensure that the MAV docks safely with the MOTV. The MOTV will need to have a highly adaptable docking system, capable of receiving multiple payloads from various MAV designs, and will likely be equipped with autonomous systems to facilitate the docking process. During this rendezvous, astronauts will transfer from the MAV to the MOTV, and the return spacecraft will prepare for Earth departure. 

Earth Re-entry and Heat Shields

Once the astronauts have completed the long journey to earth they will face another challenge: re-entering Earth’s atmosphere. 

The spacecraft will be traveling over 25,000 miles per hour or 40,000 kilometers per hour, generating a considerable amount of friction with the Earth’s dense atmosphere, which will create intense heat that could potentially destroy the spacecraft if not properly managed.¹⁹

Just like exiting Mars orbit, ablative heat shields are the key technology for ensuring a safe re-entry to Earth. Modern heat shields are made from advanced materials, such as carbon phenolic or reinforced carbon-carbon, which can withstand temperatures exceeding 3,000°F, or 1,650°C.

Precision Landing on Earth

After making it through the atmosphere, our Mars bound vessel’s final challenge will be to ensure a precise and safe landing.

Engineers are exploring the use of precision landing systems to ensure that the spacecraft lands at the designated landing zone, which could be a specially prepared area in the ocean for splashdowns, or on land. 

The landing will likely involve autonomous systems capable of detecting any obstacles in the final descent path and making necessary adjustments in real time. Just like they did for the craft’s arrival on Mars, these guidance systems will likely rely on onboard sensors, radar, and cameras to continuously monitor the descent and adjust the spacecraft’s trajectory to land in the target area.

Engineers can try their hardest to make a Mars trip risk free, but with any high-risk mission, contingency plans are crucial to account for potential failures or unexpected situations that may arise. The stakes are incredibly high, and engineers must ensure that every possible scenario is addressed. Several emergency protocols will likely be in place to protect the astronauts and maintain mission success, including these:

Emergency Protocols During Launch and Ascent

In the event of an issue with the MAV during the launch phase, there will likely be multiple ways  to abort the mission, ensuring the safety of the crew. Emergency abort systems could be designed to help return the crew safely to the Martian surface or a safe rendezvous point.

Health and Medical Emergencies

Due to the isolated nature of Mars missions, the crew will undergo extensive training to deal with any medical emergencies that might arise, such as illness, or radiation exposure, as well as psychological conditions like stress or  trauma. Medical supplies and equipment will be part of the MAV’s payload to ensure astronauts are prepared for any emergency.

Communication and Psychological Support

Given the distance between Earth and Mars,  communication delays of up to 20 minutes one-way will prevent astronauts from accessing real-time support. However, advanced AI systems and autonomous robots will likely be on standby to assist astronauts in case of emergency repairs or other urgent situations.

Psychological support will also be essential, since isolation from Earth for extended periods can cause significant mental health impacts. Protocols will likely include regular communication sessions with loved ones and support teams, as well as mental health programs designed to minimize stress and fatigue.

Ethical Considerations: One-Way Missions

One of the most controversial concepts for future human missions to Mars is the one-way mission, where astronauts would travel to Mars with no plan to return. While NASA’s current plans involve ensuring a return trip for astronauts, there have been proposals for one-way missions aimed at colonizing Mars. However, these missions raise significant ethical concerns regarding astronaut safety and the human right to life, as well as the psychological impacts of knowing that a return to Earth is not possible. The human cost of such missions poses a moral challenge for mission planners, governments, and international space agencies.

While a trip to Mars might still seem like something out of science fiction, progress in areas like spacecraft design, propulsion, life support, and radiation protection is making the mission more achievable.

Engineers are at the heart of preparing for the first human mission to Mars, designing spacecraft that can handle the tough conditions of space travel and making sure everything works smoothly during the journey. In addition, engineers are involved in creating training programs and safety plans to make sure astronauts are fully prepared for the challenges of deep space. Thanks to their ongoing work and breakthroughs in technology, the dream of sending humans to Mars is getting closer to reality, opening up amazing possibilities for space exploration.