Earth vs mars size comparison
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Mars vs Earth Size Comparison: Planetary Dimensions and Mass
Mars is significantly smaller than Earth in both diameter and mass. The diameter of Mars is just over half that of Earth, making it the second smallest planet in the solar system after Mercury 21. Specifically, Mars has a radius of about 3,397 km, while Earth’s radius is approximately 6,371 km, meaning Mars is roughly 53% the size of Earth in terms of diameter . In terms of mass, Mars is only about a tenth the mass of Earth and Venus, which is a notable difference among the rocky planets .
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 only 37.6% of Earth’s gravity 13. This means that objects and people on Mars would weigh much less than they do on Earth.
Atmospheric Pressure and Environmental Conditions
Mars also has a much thinner atmosphere than Earth. The atmospheric pressure on Mars is about 0.6 kPa, which is roughly 100 times lower than Earth’s atmospheric pressure of 101 kPa 13. This thin atmosphere, combined with Mars’ smaller size, leads to greater temperature variations and a much colder environment compared to Earth.
Astronomical Observations and Angular Diameter
From an observational standpoint, the angular diameter of Mars as seen from Earth is about 11.1 arcseconds, compared to Earth’s 17.2 arcseconds when both are viewed from the same distance from the Sun . This further illustrates the smaller size of Mars relative to Earth.
Planet Formation and the Mars Size Anomaly
The small size of Mars is considered an anomaly in planetary formation models. While classic models predict that planets farther from the Sun should be larger, Mars is much smaller than Earth, which has puzzled scientists. Recent simulations suggest that Mars’ small size may be due to a partial gap in the solar nebula during the early formation of the solar system, limiting the material available for Mars to grow 25.
Conclusion
In summary, Mars is much smaller than Earth in both diameter and mass, with weaker gravity and a much thinner atmosphere. These differences are important for understanding the challenges of future Mars exploration and colonization, as well as the unique history of planetary formation in our solar system 1235.
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