Calculating the surface area of a sphere is crucial to understanding the size and comparison of planetary bodies. The formula used to calculate the surface area of a sphere is given by
where \( A \) represents the surface area and \( r \) is the radius of the sphere.On Earth, the radius is often simplified to \( r_e = 1 \) for ease of calculation, resulting in a surface area of \( A_e = 4 \pi \times (1)^2 = 4 \pi \). For Mars, given its radius is half of Earth's (\( r_m = \frac{1}{2} \)),
- we adjust the formula to calculate the surface area: \( A_m = 4 \pi \left(\frac{1}{2}\right)^2 = 4 \pi \cdot \frac{1}{4} = \pi \).
These computations show how varying the radius influences surface area, a concept useful in comparing celestial bodies.