There's a lovely photo of scientists manually painting the scan lines coming in from Mariner 4, like a paint by numbers picture https://www.nasa.gov/multimedia

There's a lovely photo of scientists manually painting the scan lines coming in from Mariner 4, like a paint by numbers picture https://www.nasa.gov/multimedia/imagegallery/image_feature_1982.html https://www.nasa.gov/multimedia/imagegallery/image_feature_1...