A map of the Mid-Atlantic Ridge. The Mid-Atlantic Ridge (MAR) is a mid-ocean ridge, a divergent tectonic plate or constructive plate boundary located along the floor of the Atlantic Ocean, and part of the longest mountain range in the world.
Since the distances are so large, we usually express them in Astronomical Units (AU). (An AU is the average distance from Earth to the Sun, about 150 million kilometers or 93 million miles.) The table below lists the distance of each planet from the Sun in AU. (Numbers were taken from this page.)
This week, as a box of electronics called New Horizons prepares to complete a nearly 10-year journey to Pluto, it's a good moment to reflect on just how far away even the objects in our astronomical backyard are from us. When astronomers measure distances in solar systems their meter stick is the average distance between Earth and the sun. It's called an astronomical unit, or AU, and it equals about 93 million miles. Earth obviously lives at 1 AU from the sun. Mars is about 1.5 AU.