From hostile deserts to lonely islands and the highest mountains, wherever there is space to expand into, humans do so. It is hardly surprising that we are already preparing to set foot on Mars and create the first permanent colony outside of Earth—perhaps even terraform another planet into a second blue home. However, before we can achieve such a future, we must first complete the second phase of colonization: establishing a semi-permanent outpost to prepare the ground for a larger human presence.
But doing so will be extremely challenging. Even for an expansionist species like ours, Mars is extreme. At first glance, Mars seems familiar with its polar ice caps, vast valleys, liquid water beneath the surface, and a day barely longer than Earth's. Unfortunately, Mars is actually a cold, radioactive desert where the ground is poisonous, and breathing is impossible. It is an incredibly hostile environment, and the pioneers working there will face intensely stressful conditions, filled with challenges never encountered before. Despite this, there are plenty of people willing to take on the task, and we have the technology to support them.
For this scenario, we will assume prior missions have scouted a suitable location for an outpost, stored resources and equipment, and established a moon base as a hub for Mars missions. One major challenge our outpost will face is Mars' energy scarcity. Due to its distance from the Sun, solar power is only 40% as effective as it is on Earth. This issue is worsened by massive dust storms that can obscure sunlight for days. Solar power alone will likely not be sufficient. Alternatives such as wind power and geothermal energy are also impractical due to the thin atmosphere and Mars' cold interior. Initially, nuclear technology might be the only viable option, requiring nuclear fuel and reactors imported from Earth.
Yet all the energy in the world would be useless without breathable air. Mars' atmosphere is only 1% as dense as Earth's and composed mostly of CO2. Habitats must be pressurized and filled with a breathable nitrogen-oxygen mixture. To withstand pressure differences, the structures will need rounded, smooth shapes, while airlocks must be perfectly airtight. Without a protective magnetosphere or dense atmosphere, half of the radiation from space reaches the surface, subjecting inhabitants to 50 times the radiation levels experienced on Earth. A three-year stay would exceed the career radiation dose limit for NASA astronauts, significantly increasing cancer risks.
To mitigate this, habitats could be shielded with thick layers of frozen CO2 harvested from the atmosphere and further covered with a meter of dirt for additional protection. Unfortunately, this means living spaces would be mostly windowless tunnels, resembling burial mounds from the outside. While this shielding would reduce radiation to survivable levels, it would not protect those venturing outdoors. Therefore, remote-controlled robots will likely perform routine surface tasks while the crew remains inside.
Staying indoors is also essential due to Mars' dust, which is finer and drier than Earth's, making it electrostatically charged and prone to sticking to everything, including spacesuits. Worse still, the Martian soil contains toxic perchlorate salts, which can be deadly with constant exposure. Specialized spacesuits that remain attached outside the habitat could help minimize contamination risks.
Having secured energy, air, and basic protection, the next challenge will be providing food. Water is relatively accessible near the Martian poles with their thick ice layers. However, growing food presents another challenge, as Mars' alkaline soil lacks vital nitrogen compounds necessary for plant growth. The soil must be decontaminated and fertilized with recycled biological waste, a process that will be both time-consuming and energy-intensive. Aquaponics, combining fish and plant farming, could provide a more sustainable and diverse food source, offering psychological benefits as well.
A critical issue yet to be resolved is Mars' low gravity, which is only 38% of Earth's. Prolonged exposure to low gravity can lead to muscle wasting, bone loss, and cardiovascular problems. While future rotating habitats might help simulate gravity, for now, crews would need to exercise frequently to minimize physical degradation.
The psychological strain will also be intense. Crew members will spend years confined in tight, windowless spaces with limited contact from Earth and repetitive routines. Like Antarctic scientists or submarine crews, they will require extensive psychological screening to ensure mental resilience for the long mission.
Establishing the first real infrastructure on Mars will demand immense effort from a select group of determined, highly skilled individuals. Fortunately, Earth has no shortage of such people. A small Mars base could survive for several decades, provided it receives consistent shipments of resources, spare parts, nuclear fuel, and rotating crews from Earth. However, the vast distance between Mars and Earth, along with narrow travel windows every two years, means any emergencies could be catastrophic, with aid arriving too late.
Settling Mars will be humanity's greatest challenge yet—grueling, dangerous, and filled with uncertainty. Yet we are a stubborn species, drawn to extreme challenges. If we can conquer Phase Two of colonization, anything becomes possible: cities lighting the Martian night, a hub for interplanetary travel, and industries expanding into orbit, paving the way for a true multi-planetary future. Reaching Mars will be incredibly difficult but immensely rewarding. If we persist, we may live to witness humanity's first steps toward becoming a spacefaring civilization, cheering on the brave souls who will build this future for us all.