This self-portrait of NASA's Mars rover
Curiosity combines dozens of exposures taken
by the rover's Mars Hand Lens Imager on Feb.
3, 2013 plus three exposures taken May 10,
2013 to show two holes, in lower left
quadrant, where Curiosity used its drill on
the rock target "John Klein."
NASA/JPL-Caltech/MSSS NASA's Curiosity rover has found new evidence of nitrogen on Mars, proving that the red planet has -- or at least had -- the right stuff to sustain life.
The rover drilled into Martian rocks and discovered evidence of nitrates, which are essential compounds to the building blocks of life.
"The discovery adds to the evidence that ancient Mars was habitable for life," NASA said in a blog post.
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