Image of the Day: Grand Canyon of Mars -Stretches for 2,485 Miles


Imagine a canyon that stretches from San Francisco to Washington DC, and you'll have an idea of the immensity of Mars' Valles Marineris, an enormous gorge first spotted by the NASA spacecraft Mariner 9 in 1972, and named in the spacecraft's honor.

Valles Mareneris stretches 2,485 miles across Mars surface, and reaches depths of 6.2 miles (the Grand Canyon by contrast  plunges 1.1 miles down at its deepest point). Valles Marineris is thought to be a rift valley, formed by uplift when hot material from the Mars's mantle bubbled up and stretched the planet's crust.



"The Galaxy" in Your Inbox, Free, Daily