Getting humans to Mars isn’t just about building a big rocket and launching it. It’s a complex, multi-decade puzzle where every piece has to fit perfectly - from how you get there, to how you survive once you land. NASA’s current plan, called the Human Mars Mission Architecture, isn’t a single spacecraft or a quick trip. It’s a full system: transportation, landing, power, habitats, and even how you get home. And it’s being tested right now - not on Mars, but on the Moon.

How You Get to Mars: Propulsion and Mission Design

There are three main ways to get people to Mars, and each has trade-offs in mass, speed, and cost. Chemical propulsion, the kind used for Apollo and the Space Shuttle, is reliable but heavy. It needs a total mission mass of 657 tonnes, meaning you’d need multiple massive rockets just to launch everything. Solar electric propulsion is lighter - around 467 tonnes - but it’s slow. It can take years to reach Mars, which isn’t safe for astronauts exposed to radiation and microgravity for too long.

The current favorite? Nuclear thermal propulsion. It cuts the total mission mass down to 436 tonnes and slashes transit time to about 6 months. That’s a big deal. Less time in space means less radiation exposure, lower life support needs, and fewer risks. NASA’s 2024 Architecture Concept Review confirmed this as the leading option, partly because it works with the split-mission strategy: send cargo ahead of crew.

That strategy means sending landers, power systems, and habitats to Mars years before astronauts even leave Earth. These systems land, deploy, and sit there waiting. When the crew arrives, they’re not landing on an empty planet - they’re walking into a pre-built base. It’s like setting up a campsite before your friends show up. SpaceX’s Starship could make this cheaper, potentially dropping the cost to $10 million per tonne sent to Mars - a tenth of what traditional systems cost.

Landing on Mars: The Hardest Part

Mars has a thin atmosphere - just 0.6% of Earth’s. That’s not enough to slow down a heavy lander with parachutes alone, but too thick to ignore like on the Moon. Landing 10+ metric tons safely is the biggest engineering challenge NASA faces. The sky crane system that landed Perseverance works for rovers, but not for crewed landers weighing 20 to 30 tonnes.

NASA’s current EDL (Entry, Descent, and Landing) design must place astronauts within 100 meters of pre-deployed equipment. That’s like landing a truck next to a tent in a sandstorm, blindfolded. To make this work, they’re developing advanced supersonic parachutes, retro-rockets, and precision navigation systems. Testing happens on Earth using high-altitude balloons and wind tunnels, but real validation will come from lunar landings under Artemis. The lunar South Pole, with its rough terrain and extreme shadows, is being used as a Mars analog. If you can land precisely there, you can land on Mars.

Power on Mars: Why Nuclear Is Non-Negotiable

On Mars, the sun doesn’t always shine. Dust storms can last weeks, covering solar panels like a thick blanket. Temperatures drop to -100°C at night. Solar power alone won’t cut it for a crewed base.

In December 2024, NASA made its first formal Mars architecture decision: nuclear fission power. It’s the only technology that works 24/7, regardless of weather or season. The system will generate 40 kilowatts - enough to run life support, science labs, and communications for four astronauts. It’s compact, reliable, and designed to last five years without major repairs - twice as long as the International Space Station’s systems.

This isn’t science fiction. NASA and the Department of Energy have already tested prototype reactors on Earth. The first unit will be sent to Mars before the crew, and it will start up automatically once landed. No human intervention needed. That’s critical. If your power goes out, you die.

Living on Mars: Habitats and Survival

Initial Mars habitats will be small - just enough for four people for 30 to 60 days. They’ll be built from pre-deployed modules, likely covered in regolith (Martian soil) to shield against radiation. Think of them as underground bunkers with windows. Airlocks, water recyclers, and waste processors will be packed inside. The goal isn’t comfort - it’s survival.

Every system must work without fail. NASA requires a reliability rate higher than anything ever flown in space. The ISS can go three years without a major failure. Mars habitats must last five. That’s because rescue isn’t an option. If a life support system breaks, you fix it - or you don’t breathe.

Logistics matter too. Cargo landers will deliver 5 to 10 metric tons of supplies: spare parts, food, science tools, and communication gear. Every item is chosen because it’s essential. No extras. No junk. Everything has a purpose.

Why Mars Sample Return Is the Key

Before humans land, NASA must know what they’re walking into. That’s why the Mars Sample Return (MSR) mission is so important. It’s not just about bringing back rocks. It’s about learning where to build, what materials to use, and what hazards to avoid.

Lockheed Martin’s lead architect on MSR says these samples will tell us how to survive and thrive on Mars. Are there perchlorates in the soil that poison water? Is the dust magnetic and damaging to equipment? Is there organic material that could contaminate our samples - or ours? These questions can’t be answered by robots alone.

The MSR mission, planned for launch in 2030-2031, involves a lander, a Mars Ascent Vehicle (MAV), and a European Return Orbiter. But it’s stuck in limbo. NASA hasn’t picked the final design yet. One option is an upgraded sky crane - expensive, at $6.6-7.7 billion. The other is a commercial lander - cheaper, but unproven. The decision, expected in mid-2026, will shape the entire timeline for human missions.

Costs, Risks, and the Long Road Ahead

Everything costs money. The MSR mission alone could run $5.8-7.1 billion. The full human Mars program, if funded steadily, could need $7.2 billion per year through 2035. That’s a lot - but it’s less than the annual cost of the U.S. military’s F-35 fighter program.

The biggest risks? Landing reliability and political will. Right now, NASA estimates only an 87% chance of successfully landing a 10+ tonne payload on Mars. That’s too low. They need 95%. And if Congress cuts funding after a decade, the whole plan stalls - again.

International partners are stepping in. ESA is contributing the Return Orbiter. Twenty-two European nations have already invested $1.2 billion. Blue Origin and SpaceX are developing technologies that could cut costs. But none of this matters if the public loses interest.

Training and the Human Factor

Astronauts won’t just fly to Mars. They’ll need to operate like engineers, geologists, medics, and mechanics - all at once. NASA is building simulators that replicate Mars’ gravity, dust, and terrain. Crews will train for over 500 hours in simulated surface operations before launch. They’ll learn to fix life support with spare parts, drill for ice, and communicate with Earth with a 20-minute delay.

Planetary protection adds another layer. Every surface robot or habitat must be sterilized to 99.999% to avoid contaminating Mars with Earth microbes. That process adds 15% to mission costs and complicates every design decision.

When Will Humans Land?

Don’t expect a Mars landing by 2035. Even the most optimistic timelines put it between 2040 and 2045. That’s not because the tech is impossible - it’s because the system is too complex to rush. NASA’s approach is deliberate: test on the Moon, learn from sample return, build reliability step by step.

The architecture isn’t about beating a deadline. It’s about making sure when humans do land, they don’t just survive - they thrive. And that’s worth the wait.