The tiny, potato-shaped moon Phobos, one of two Martian moons, cast a silhouette as it passed in front of the Sun, creating an eye in Mars’ sky.

From its perch on the western wall of Mars' Jezero Crater, NASA's Perseverance rover recently spied a "googly eye" peering down from space. The pupil in this celestial gaze is the Martian moon Phobos, ...