Curiosity touched down in a crater near the Martian equator last month. The red planet today is dusty and dry but scientists think it was once warmer and wetter. 

Evidence of an ancient stream came from analyzing the size and shapes of pebbles and gravel near Gale Crater. 

Mission scientists said Thursday it appeared the water was fast-moving and deep. Images from space have provided hints of a watery past at Curiosity's landing site. 

The latest discovery on the ground confirms that. Curiosity is headed toward a spot where three types of terrain meet. 

Its ultimate destination is a mountain rising from the center of the crater.

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