Today On Mars: First Physical Evidence Of A Once-Flowing Stream
Observable Evidence Of Water On Mars NASA/JPL-Caltech/MSSS For the first time, scientists can actually observe the remnants of water on Mars. Scientists have known that water flowed on Mars at one point, but until now, what that flow looked like has remained educated speculation. Now a discovery changes that. Mars rover Curiosity has found gravel that was once part of an ancient stream. This image shows the Martian rock outcrop where that gravel is. There's a few facts we already know. Scientists started taking a closer look, and from the size of the gravel, we know the speed of the water in the stream (about three feet per second) and its depth (between ankle- and hip-deep). The roundness of the stones in the gravel even indicate they traveled long-distance, from above the rim of the Gale Crater (the slope of the crater is Curiosity's destination). We can also...