It was one of a twin set of spacecraft designed to take images of Mars, and the first one failed. Dan Goods/NASA/JPL-CaltechThe transmission was incredibly slow by today’s standards, given that the Perseverance rover regularly sends back batches of high-resolution images from Mars. Together, they revealed craters on the Martian surface and clouds floating above in the atmosphere, both of which surprised scientists. The highest-resolution Mariner 4 image (right) revealed the cratered Martian surface from 7,830 miles (12,601 kilometers) above. JPL/NASAThe snapshots showed less than 1% of the Martian surface, missing the more diverse features on the planet’s surface that later missions such as Viking 1 would capture.

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Persons: Pasadena , California CNN —, Mars, “, ”, David Delgado, Percival, Dan Goods, Richard Grumm, Grumm, ” Delgado, William Pickering Organizations: Pasadena , California CNN, Spacecraft, NASA’s Jet Propulsion Laboratory, NASA’s, JPL, Mariner, Venus, NASA Mariner, NASA, Caltech, Jet Propulsion Laboratory Locations: Pasadena , California, High, Pasadena, Flagstaff , Arizona, Goldstone , California