"Hundreds of large spirals have been discovered on Mars, and scientists think the coiled features are evidence of a type of lava flow never before seen on the red planet.
If so, the spirals would suggest that volcanoes—not ice floes, as other experts believe—shaped an unusual area near the red planet's equator.
Athabasca Valles is a region of flow channels and valleys covered with terrain plates, structures that show clear evidence of something fracturing and drifting across the planet's surface million years of years ago."
An avalanche on Mars captured by the HiRISE camera on the Mars Reconnaissance Orbiter on November 27, 2011.
Supercomputer simulation showing the tangled magnetosphere surrounding Earth.
See also this excellent paper by astrobiologist Chris McKay.
From the summary:
“Planetary ecosynthesis on Mars is being seriously discussed within the field of planetary science. It appears that restoring a thick atmosphere on Mars and the recreation of an environment habitable to many forms of life is possible. It is important now to consider if it “should” be done. To do this takes us into new and interesting territory in environmental ethics but both utilitarian and intrinsic worth arguments support the notion of planetary ecosynthesis. Strict preservationism arguments do not. It is important to have the long-term view of life on Mars and the possibilities of planetary ecosynthesis. This affects how we explore Mars now. Mars may well be our first step out into the biological universe, it is a step we should take carefully.”
Infographic via Brian Crystie Design
"You can enjoy looking back through history at all the missions we've launched to the Red Planet — and where they are now....When you look at something like this, you realize that humans really aren't going to give up on the dream of going to space any time soon. Look how many times we've already hurled our spacecraft at Mars ! And we've only been launching missions to space for a little over half a century."