The most ambitious target for a human Mars landing is 2029, set by SpaceX. NASA has not committed to a specific year but frames crewed Mars missions as a goal for the late 2030s or 2040s. China has outlined plans that could put astronauts in Mars orbit by the mid-2030s, with a surface base potentially following in 2038. The honest answer is that no one knows for certain, because the mission depends on solving engineering problems that have never been solved before, at a cost likely exceeding $500 billion.
SpaceX’s Step-by-Step Plan
Elon Musk outlined a phased approach in 2024 that begins with five uncrewed Starship flights launching toward Mars in 2026, when Earth and Mars next align for efficient travel. If those succeed, the 2028 window would see roughly 20 more Starships depart, mostly carrying robotic systems to survey for water ice, prepare landing pads, and set up power generation. At least one of those 2028 ships would carry human passengers, though Musk has also cited 2029 as the target for the first crewed landing.
These dates have shifted repeatedly. Musk originally discussed crewed Mars flights as early as the mid-2020s, then pushed them back. The 2026 uncrewed window is the nearest hard test: if Starship can’t reach Mars autonomously by then, the crewed timeline slides by at least 26 months, the gap between each launch window when the two planets are close enough for a practical transfer.
A 2025 feasibility study published in Scientific Reports found that a 90-day transit to Mars is achievable with Starship’s existing chemical propulsion, provided the spacecraft can keep its fuel cold enough during the trip. That’s a meaningful finding because it means SpaceX doesn’t need nuclear propulsion or other experimental engines to make the journey. The engineering challenge shifts to fuel storage, life support, and landing a vehicle far heavier than anything that has touched down on Mars before.
NASA’s Moon-First Approach
NASA treats Mars as the destination at the end of a long proving ground on the Moon. The Artemis program is building that foundation: landing astronauts on the lunar surface, testing habitats, and developing the systems needed for deep-space travel. The agency’s 2024 architecture update added two new elements to the plan, a lunar cargo lander and a surface habitat, both of which are stepping stones toward Mars. No official year for a crewed Mars landing has been announced.
Independent cost estimates give some sense of why NASA moves cautiously. The National Research Council estimated a first crewed Mars mission at $300 to $600 billion in current dollars. A separate analysis put the figure at roughly half a trillion. For context, the International Space Station cost about $150 billion over its lifetime, including launches. A Mars mission would require two to four times that investment. NASA’s annual budget is around $25 billion, so the funding has to accumulate over decades or be supplemented by international and commercial partners.
China’s Parallel Timeline
China’s space agency has been building toward Mars methodically. A three-step plan presented by Chinese officials at international conferences starts with robotic site-selection missions around 2033, followed by a crewed orbit-only mission around 2035. Representatives from China’s Deep Space Exploration Lab have shown plans for a Mars research base by 2038, though original roadmaps from the Chinese Academy of Sciences described “crewed Mars exploration around 2050” and carefully distinguished that from a surface landing.
At UN space committee meetings in 2023 and 2024, China’s space agency presented designs for a crewed deep-space vehicle arriving around 2040. The gap between these various Chinese timelines, 2035 for orbit versus 2050 for full exploration, reflects the difference between an ambitious target and a conservative institutional forecast. Either way, China is the only other nation besides the United States with a concrete, publicly stated roadmap for sending people to Mars.
Why Mars Is So Hard to Reach
Launch windows to Mars open roughly every 26 months. The upcoming windows fall in 2026, 2028, 2030, 2032, 2035, and 2038. Miss one and you wait more than two years for the next. A round trip, including time on the surface waiting for the planets to realign for the return flight, takes roughly two to three years total.
Landing is the single biggest unsolved engineering problem. Every successful Mars landing to date, all five by the United States, put less than 0.6 metric tons on the surface. A crewed mission needs to land 40 to 80 metric tons: habitats, power systems, life support, supplies, and the vehicle itself. That’s a jump of roughly 100 times the heaviest payload ever landed on Mars. The thin Martian atmosphere, about 1% as dense as Earth’s, provides very little braking for a heavy vehicle descending to the surface.
Then there’s oxygen. NASA’s MOXIE experiment on the Perseverance rover proved that oxygen can be pulled from the carbon dioxide in Mars’s atmosphere. Over its full mission, MOXIE produced 122 grams of oxygen, about what a small dog breathes in 10 hours, at a peak rate of 12 grams per hour. A crew would need industrial-scale oxygen production, both for breathing and, more critically, for manufacturing the rocket fuel needed to launch back to Earth. The next step is building a full-scale system that can generate, liquefy, and store oxygen continuously.
Radiation and the Human Body
A Mars mission exposes astronauts to far more cosmic radiation than any current spaceflight. For a 650-day mission profile (transit both ways plus surface time), radiation dose estimates with standard spacecraft shielding land around 680 millisieverts. NASA’s current career exposure limit is 600 millisieverts. That means under today’s rules, no NASA astronaut could complete a Mars mission without exceeding the agency’s own safety threshold.
This doesn’t make the mission impossible, but it forces hard choices. Shielding can be increased at the cost of added weight, which compounds the landing problem. Mission planners can also time flights to coincide with solar maximum, when the sun’s magnetic field deflects more galactic cosmic rays, reducing exposure. Faster transit times help too: a 90-day one-way trip instead of a 180-day coast cuts radiation exposure during the most vulnerable phase, when astronauts are outside Earth’s protective magnetic field with no planet to shelter behind.
A Realistic Window
If SpaceX lands uncrewed Starships on Mars in 2026 and everything works, a crewed attempt in 2028 or 2029 is at least conceivable. But “everything works” is doing enormous lifting in that sentence. The vehicle has to survive entry through Mars’s atmosphere at a mass no one has ever attempted, land precisely, and function on the surface. If those early flights reveal major problems, a crewed landing likely slides into the early 2030s at best.
NASA’s more conservative path probably puts boots on Mars no earlier than the late 2030s, and only if Congress funds the mission consistently across multiple presidential administrations. China’s timeline suggests the mid-to-late 2030s for an orbital mission, with a surface presence following later. The most likely decade for the first human to stand on Mars is the 2030s, but the 2040s remains entirely plausible if technical problems prove stubborn or political will falters. The gap between the most optimistic and most cautious forecasts spans roughly 20 years, which is itself a measure of how much uncertainty remains.