From the article: "When your resolution is too low to fully resolve an object, it tends to look rectangular because the pixels in the image are squares. Any cur

From the article: "When your resolution is too low to fully resolve an object, it tends to look rectangular because the pixels in the image are squares. Any curve will look like a series of straight lines if you reduce your resolution enough." Like the "face," this is most likely the combination of the right angle and shadowing, low resolution, and our hopes of finding something earth-shattering on an alien planet.