Mars has suddenly gotten more interesting thanks to a science sleuth who combined his knowledge of the Himalayas with photo reconnaissance of the Red Planet.
UCLA scientist An Yin reports that Mars may be the only other planet in the solar system with plate tectonics.
Since the middle of the last century we've known that Earth's crust is broken into several dozen plates bumping and grinding to make mountains and power chains of volcanoes, which recycle surface material and control the carbon dioxide balance in our atmosphere.
By comparison, Mars has a mobile yet very sluggish crust divided into just two plates Yin says, "Mars is at a primitive stage of plate tectonics. It gives us a glimpse of how the early Earth may have looked."
One of the biggest surprises from our first orbital reconnaissance of Mars in 1971 was the discovery of the solar system's largest canyon system, which would stretch from Los Angeles to News York, and is five times the depth of the Grand Canyon in Arizona.
The origin of this "grandest canyon" - called Valles Marinaris after the NASA orbiter Mariner 9, - has been a puzzle over the past 40 years. Some suggestions are that it is just a big crack that opened up on the Martian surface. A more recent theory proposes that it formed from a giant collapse when salts were heated up and released water that rushed out through underground channels.