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===> How far is the Earth from Mars?

Mars

Distance from Earth
	Minimum (106 km)	55.7
	Maximum (106 km)	401.3

Source: Planetary Sciences at the National Space Science Data Center


The distance between two planets can vary widely depending on where they are in their orbits.
perihelionaphelionsemimajor axis
Mars206.62 (106 km)249.23 (106 km)227.92 (106 km)
Earth147.09 (106 km)152.10 (106 km)149.60 (106 km)

Perihelion: the point in a body's orbit closest to the Sun, in 106 kilometers.
Aphelion: the point in a body's orbit furthest from the Sun, in 106 kilometers.
Semimajor axis: the mean distance from the Sun in 106 kilometers.

Source: Planetary Sciences at the National Space Science Data Center


I can show you some diagrams of the current (or recent) positions of the planets:


Mars

Mars is about 34,600,000 mi. (55,700,000 km) away from the Earth at its closest approach.

Source: WorldBook