Voyager 2's encounter of Uranus began Nov. 4, 1985 with an observatory phase. Activity built to a peak in late January 1986, with most of the critical observations occurring in a six- hour period in and around the time of closest approach. The spacecraft made its closest approach to Uranus at 9:59 a.m. PST on Jan. 24.

To prepare for the flyby of this unusual planetary system, engineers extensively reprogrammed Voyager 2's onboard computers via radio control from the ground. They endowed the spacecraft with new capabilities that would enable it to return clear, close-up pictures despite the dim light and high velocity at which Voyager would be passing its targets. (Uranus receives about 1/400th of the sunlight that falls on Earth.)

In addition, giant antenna receiving stations on Earth were linked electronically in order to capture and enhance Voyager's faint radio signal.