Strange structures and deserted landscapes. No, these aren't images cut from an old comic book or graphic novel. They're an artist's renderings of what Mars was imagined to look like in 1975. NASA summarized what was known about the planet more than 35 years ago: "Compared to Earth, Mars is further away from the light of the sun, very cold and very arid, and had a thin atmosphere rich in carbon dioxide but little nitrogen, an environment distinctly inhospitable to complex, Earth-like, carbon-based life forms."
"The artist drew silicon-based life forms, probably coached by others, perhaps scientists, who had thought about such possibilities," NASA explained. "Peculiar saucer-like shapes stood only slightly above ground level, root-like structures reached outward for growth resources; a bundle of cones faced many directions for heat, light or food. Instead of reality, the images embodied the artist's hope and anticipation of what future Martian exploration would find."
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