How far away is Mars? The exact answer varies, of course, as both it and our planet are constantly moving along their own orbits around the Sun. But on average, Mars is about 225 million km/140 million miles from Earth. Give or take a few.
To most people (myself included) those are just numbers. Big numbers — and really not even all that big in an astronomical sense. So to give a sense of what it means to cross the distance between here and Mars, interactive designer David Paliwoda created a web page that illustrates the scale involved quite nicely. If our entire planet were reduced to a sphere 100 pixels in diameter, and you could travel outward at a velocity of 200,000 km/h (7,000 pixels/second, in his model) how far would Mars be?