Mars and Mercury Size Comparison

A simulation showing the true scale difference between Mars and Mercury.

Created by Astrosyo
Mars and Mercury shown at accurate relative size.

What the simulation shows

This visualization places Mars and Mercury next to each other using their real physical diameters and full 3D geometry. Mars, famous for being a potential target for future human missions, appears rusty and textured with mountains, canyons, and polar caps. Mercury, on the other hand, looks like a heavily cratered, airless world resembling an oversized Moon. When seen at true scale, Mars is noticeably larger, making Mercury appear far smaller than people often imagine. Both rotate in place, giving a clear sense of their comparative sizes.

The numbers behind the scale

Mercury’s diameter is approximately 4,880 km. Mars has a diameter of about 6,779 km. The ratio of their diameters is:

DMDMe=6,7794,880≈1.39\frac{D_M}{D_{Me}} = \frac{6{,}779}{4{,}880} \approx 1.39

Volume scales with the cube of the diameter:

(1.39)3≈2.70(1.39)^3 \approx 2.70

This means Mars has almost three times the volume of Mercury. Surface area, which determines how large each planet appears visually, scales with the square of the diameter:

(1.39)2≈1.93(1.39)^2 \approx 1.93

So Mars has nearly twice the visible surface area of Mercury. The simulation preserves these exact proportions in 3D space, letting the size difference be experienced visually rather than interpreted through numbers.