Take a close look. Focus on the tiny star about 3 inches above the hills. It's Earth.
This view of the twilight sky and Martian horizon taken by NASA's Curiosity Mars rover includes Earth as the brightest point of light in the night sky. Our moon is just below Earth.
Researchers used Curiosity's Mast Camera to capture this scene about 80 minutes after sunset on the 529th Martian day, or sol, of the rover's work on Mars -- Jan. 31, 2014, Earth time. The image has been processed to remove effects of cosmic rays.
A human observer with normal vision, if standing on Mars, could easily see Earth and the moon as two distinct, bright evening stars.
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