The car-sized Curiosity rover has spotted evidence of once quite hospitable environs on Mars. As shown in the imagery below, the NASA robot investigated dried-up lake beds and captured views of ripple formations on their ancient shorelines.

An exploding budget and an unraveling schedule spell disappointment for NASA's mission to learn more about Mars's history.

NASA has found signs of a lake on Mars, with evidence suggesting the presence of water rather than just ice. Researchers discovered ripples in the sandy shores of ancient lakebeds on Mars, which were likely created by the movement of water pushed by wind.