Ten years ago, Dutch scientist-turned-artist Theo Jansen had a vision: art that evolved. The evolution of his bizarre machines that walk when powered by gusts of wind took place on a computer. Trained as a physicist (he was a doctoral student but did not finish), Jansen designed a program that simulated pairs of legs of different lengths. He then created virtual creatures and raced them against each other to find the ones that moved most efficiently. These he built, and he hopes one day to find a way to let them evolve on their own. In the meantime, he is working on ways to keep them moving even after the wind dies down. Their legs are comprised of pistons inside a tube, connected to a crankshaft. Once a gust of wind gets the sculpture going (most have polystyrene windmill blades or sails to give them a boost) and the pistons start moving, the legs could function as pumps and store compressed air. The critter could then burn that stored energy to keep puttering along regardless of the weather. "It's like giving it muscles," says Jansen with delight.
Next someone's gonna claim that Lee Harvey Oswald acted alone.
Mars in the popular imagination is a planet that was once warm and wet, a place that might have fostered life. But new research shows how these imagined pleasant periods were brief, hellish, and punctuated by utter catastrophe.
[...] Roughly 25 space rocks between 60 and 150 miles in diameter (100-250 kilometers) gouged the Martian surface every 10-20 million years back then. An impact of this size would rock the planet, fueling quakes and volcanic activity. But that would not be the end of it. A typical impact, Segura said, would have generated enough water in the ensuing years to bury the entire planet under "tens of meters" of water, or more than the height of a two-story building.
[...] Segura described the details of a typical large impact, one roughly ten times bigger than the 6-mile-wide (10-kilometer) asteroid suspected of killing off the dinosaurs. Vaporized rock and ice from the incoming object and the impact site expands ballistically in a huge cloud, she said, filling the global atmosphere.
Eventually, the atmosphere cools enough to condense the water. Heavy rains ensue -- up to six feet of scalding rain every year -- lasting for perhaps hundreds of years. Meanwhile, the hot rock layer melts ice in the soil of Mars. [...] "We find that globally, Mars will be above the freezing point of water -- all water will be in the liquid phase -- for years to millennia for the largest objects."
[...] While some scientists have theorized that the wet periods on Mars fueled longer lasting, greenhouse-like climates that would have been kind to evolution, Segura and her team think otherwise. They envision a cold and dry planet, "an almost endless winter, broken by episodes of scalding rains followed by flash floods."