The two 80's Voyager missions to Jupiter were one of the highlights of the decade in planetary missions. There were some images from the two Voyagers that were closer in detail that we can hope to do from Earth orbit, but this image above comes close. You wouldn’t know this was not a Voyager, or even a Galileo mission image except for the fact its not. Hard to imagine that only 20 years ago we couldn’t see a single detail on Ganymede’s surface without actually sending a probe to the Jupiter system. This view from Hubble is, “so sharp that astronomers can see features on Ganymede's surface, most notably the white impact crater, Tros, and its system of rays, bright streaks of material blasted from the crater”.