Mars surface
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Atmospheric Composition
Atmosphere#CO₂#pressure#oxygen#nitrogen

Atmospheric Composition

What you breathe — or rather, cannot

Mars possesses a thin atmosphere composed primarily of carbon dioxide. At the surface, atmospheric pressure averages just 0.636 kPa — less than 1% of Earth's sea-level pressure of 101.3 kPa. This has profound implications for every aspect of surface operations, from suit design to habitat pressurization to the viability of in-situ resource utilization.

Surface Pressure
0.636 kPa avg
Earth Equivalent
~0.6% of Earth
Scale Height
~11.1 km
Mean Temperature
−60°C

Composition by Volume

The Martian atmosphere is dominated by CO₂, with trace amounts of nitrogen and argon. Oxygen is present in only minute quantities — far below the threshold required for human respiration without supplemental systems.

GasPercentageGame Relevance
Carbon Dioxide (CO₂)95.32%MOXIE-type O₂ extraction feedstock
Nitrogen (N₂)2.6%Habitat pressurization buffer
Argon (Ar)1.9%Inert — limited utility
Oxygen (O₂)0.13%Insufficient for respiration
Carbon Monoxide (CO)0.08%Toxic — EVA hazard
Water Vapor (H₂O)~0.03%Trace — humidity management

Implications for Gameplay

In Mars Mission Simulator, atmospheric pressure directly governs your habitat's pressurization load and power budget. Maintaining 101 kPa inside a habitat on a 0.636 kPa planet requires continuous mechanical support. A breach — even a small one — is a mission-critical event. The game models pressure differential, seal integrity, and the cascading failures that follow a compromised airlock.