Earth vs mars size
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Earth vs Mars Size: Planetary Diameter and Mass
Mars is significantly smaller than Earth. The diameter of Mars is just over half that of Earth, making it the second smallest planet in the solar system after Mercury 136. Specifically, Mars has a radius of about 3,397 km, while Earth’s radius is about 6,371 km . In terms of mass, Mars is only about one-tenth the mass of Earth and Venus, which is a notable difference that current planetary formation models still struggle to fully explain .
Surface Gravity and Density Differences
Mars’ smaller size and lower density result in much weaker surface gravity compared to Earth. The surface gravity on Mars is about 3.71 m/s², which is roughly 38% of Earth’s gravity 346. This means that objects and people on Mars would weigh much less than they do on Earth.
Atmospheric and Structural Implications
The smaller size and lower gravity of Mars also contribute to its thin atmosphere, which has a surface pressure about 100 times lower than Earth’s 346. This creates unique challenges for future colonization, as structures on Mars must be designed to withstand internal pressure rather than support their own weight, which is the main concern on Earth .
Planetary Formation and the Mars Size Mystery
Classic models of solar system formation predicted that Mars should be closer in size to Earth, but it is much smaller than expected 15. Recent simulations suggest that Mars’ small size may be due to a partial gap in the solar nebula during its formation, which limited the material available for Mars to grow .
Conclusion
In summary, Mars is much smaller than Earth in both diameter and mass, with only about 38% of Earth’s gravity and a much thinner atmosphere. These differences are important for understanding planetary formation and present unique challenges for future exploration and colonization of Mars 13456.
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