Final answer:
Scientists could create a thicker atmosphere inside a dome on Mars, where the current thin carbon dioxide atmosphere makes surface temperatures very cold. Subsurface conditions might allow for liquid water, hinting at the possibility of life in protected environments below the Martian surface.
Step-by-step explanation:
On Mars, scientists could create a thicker atmosphere in a dome rather than attempting to thicken the entire Martian atmosphere globally.
The atmosphere of Mars today has an average surface pressure of only 0.007 bar, which is less than 1% that of Earth's, and consists primarily of carbon dioxide (95%).
This thin atmosphere results in temperatures generally below freezing, contrasted with Venus, which has a thick carbon dioxide atmosphere that keeps its surface temperature at a sizzling 700 K (900 °F) due to a CO₂ greenhouse effect.
However, conditions a few meters below the Martian surface could support liquid water, indicating potential for more earthlike conditions in protected environments.
These findings suggest that while surface liquid water is not possible today due to the thin atmosphere, life could potentially persist below the surface on Mars.