Uranus, by Voyager 2

Credit: NASA

The fly-by of Voyager 2 past the planet Uranus should have been one of excitement and wonder as it had been in July 1979 and August/September 1981, when Voyager passed by the planets Jupiter and Saturn, respectively. However, four days after Voyager's closest approach to Uranus, the Space Shuttle Challenger was destroyed and the new discoveries from the outer solar system were quickly ignored in the wake of the tragedy.

This photo was taken by Voyager 2 on January 25, 1986, the day after the closest approach, at a distance of 600,000 miles (about 965,000 km). Voyager 2 is still operational, over 40 years after its launch, and is over 85.039 Astronomical Units (AU) or 7.9 billion miles (12.7 billion km) away from the Sun at this time.