Of what scientific value are the pictures that are sent back from Galileo? Or are they only used for PR?
Imaging data will make up less than 25% of all of the “bits” of scientific data returned (“downlinked”) to Earth during the orbital tour. The remainder of the downlink budget will be used to return data from other scientific instrumentation, such as infrared, ultraviolet, and fields and particles observations. It can be argued that more has been learned about the solar system from images than from any other type of instrumentation. Most astronomical discoveries through the ages have been made through either visual observations or using cameras attached to powerful telescopes. The same is true for solar system exploration using robotic spacecraft. That is why virtually every planetary exploration mission has included a camera in its payload. The value of images for public information is a wonderful bonus, but if it were not for the scientific utility of these cameras, few would be flown.
